# 16th European-African Regional Conference of the ISTVS October 11-13, 2023 | Lublin, Poland {% hint style="success" %} *Mon 2023-10-02 update*\ Pesentation Template posted [here](/conference/call-for-papers#presentation) {% endhint %} The conference is an opportunity to present and disseminate the latest scientific and technological achievements in the field of vehicle-terrain systems. Both representatives of science in the field of mechanical engineering, vehicles and machines, mechatronics and automation, soil science, agriculture and environmental engineering, as well as professionals from industry, business environment and government agencies for whom the issues discussed at the conference are an important merit are invited to participate. The organizers also count on the participation of students from under- and postgraduate courses.
The intention of the organizers is to create a friendly atmosphere and comfortable conditions for holding plenary sessions, focusing on the following issues: * soil and other deformable traction substrates including Martian and lunar regolith, snow, moschus, etc., mechanical characterization for advanced field mobility modeling as well as for minimizing the effects of soil compaction and erosion, with particular emphasis on the impact of weather factors; * driving systems of vehicles and machines, including innovative concepts of tires, wheels, and tracks for energy-saving traction; * propulsion systems, engines, mechatronic systems, and vetronics to meet the high requirements of individual customers as well as increasingly stringent environmental protection standards; * issues of regolith research of celestial bodies, the moon, Mars, asteroids for practical solutions in the field of mobility, autonomous, and robotic systems; * metrology in terramechanics, in particular new solutions for remote, autonomous measurements, using AI and maintenance-free devices and systems; * off-road vehicle dynamics; * manned and unmanned vehicles including off-road robots; * issues in the field of terramechanics and vehicle-terrain systems not mentioned above. **Jarosław Pytka**\ \&#xNAN;*Conference chair* | [*j.pytka@pollub.pl*](mailto:j.pytka@pollub.pl)\ [Faculty of Mechanical Engineering](https://wm.pollub.pl/) | [Lublin University of Technology](https://pollub.pl/) **Michał Kuszneruk**\ \&#xNAN;*Conference registrar* | [*m.kuszneruk@pollub.pl*](mailto:m.kuszneruk@pollub.pl)\ [Lublin University of Technology](https://pollub.pl/)
## Key dates | Date | Events | | ------------------ | ---------------------------------- | | 14 February 2023 | Abstract submissions open | | 15 March 2023 | Abstract submissions close | | 30 March 2023 | Authors’ notification | | 20 April 2023 | Registration opens | | 31 May 2023 | Full papers deadline | | 30 June 2023 | Authors’ notification | | 31 July 2023 | Early bird registration closes | | 15 August 2023 | Technical tour registration closes | | 31 August 2023 | Reviewed papers deadline | | 4 October 2023 | Registration closes | | 11-13 October 2023 | Conference |
## Organizing committee Jarosław Pytka, *Chair*\ Aleksander Czajka\ Leszek Gardyński\ Mateusz Klepka\ Michał Kuszneruk\ Rafał Longwic\ Aleksandra Tatarynow\ Dawid Tatarynow\ Paweł Tomiło\ Gracjana Woźniak-Borawska ### Scientific committee **Jarosław Pytka**, [Lublin University of Technology](https://2023.istvs.org/www.pollub.pl/en), Poland, *Chair*\ **Dariusz Błażejczak**, [West Pomeranian University of Technology](https://2023.istvs.org/www.zut.edu.pl/EN/university.html), Poland\ **Piotr Budzyński**, [Lublin University of Technology](https://2023.istvs.org/www.pollub.pl/en), Poland\ **Schalk Els**, [University of Pretoria](https://2023.istvs.org/www.up.ac.za), South Africa\ **Rámon Gonzalez**, [robonity](https://2023.istvs.org/www.robonity.com/index.html), Spain\ **Bradley Hansen**, [US Army Corps of Engineers,](https://2023.istvs.org/www.usace.army.mil) U.S.A.\ **Rainer Horn**, [CAU Kiel](https://2023.istvs.org/www.uni-kiel.de/en), Germany\ **Heidi R. Howard**, [US Army Corps of Engineers,](https://2023.istvs.org/www.usace.army.mil) U.S.A.\ **Genya Ishigami**, [Keio University](https://2023.istvs.org/www.keio.ac.jp/en), Japan\ **Jerzy Józwik**, [Lublin University of Technology](https://2023.istvs.org/www.pollub.pl/en), Poland\ **Thomas Keller**, [Swedish University of Agricultural Sciences](https://2023.istvs.org/www.slu.se/en), Sweden\ **Peter Kiss**, [Hungarian University of Agriculture and Life Sciences](https://2023.istvs.org/www.en.uni-mate.hu), Hungary\ **József Kövecses**, [McGill University](https://2023.istvs.org/www.mcgill.ca), Canada\ **George Mason**, [Mississippi State University](https://2023.istvs.org/www.msstate.edu), U.S.A.\ **Massimo Martelli**, [National Research Council](https://www.cnr.it/en), Italy\ **Lutz Richter**, [SoftServe, Inc.](https://www.softserveinc.com/en-us), Germany\ **Dror Rubinstein**, [Ariel University](https://2023.istvs.org/www.ariel.ac.il/wp/en), Israel\ **Vilas M. Salokhe**, [Kaziranga University](https://2023.istvs.org/www.kzu.ac.in), India\ **Corina Sandu**, [Virginia Tech](https://2023.istvs.org/www.vt.edu), U.S.A.\ **Przemysław Simiński**, [University of Natural Sciences and Humanities](https://2023.istvs.org/www.uph.edu.pl/en), Poland\ **Thomas R. Way**, [USDA-ARS, National Soil Dynamics Lab](https://2023.istvs.org/www.ars.usda.gov/southeast-area/auburn-al/soil-dynamics-research), U.S.A.\ **Vladimir Vantsevich**, [Worcester Polytechnic Institute](https://2023.istvs.org/www.wpi.edu), U.S.A.\ **Artur Zdunek**, [Institute of Agrophysics PAS](https://2023.istvs.org/www.ipan.lublin.pl/en), Poland ## Patronage A honorary patronage of:
{% hint style="success" %} *Thu 2023-09-14 update*\ Check out parallel session schedule [here](/program/overview) {% endhint %} {% hint style="success" %} *Fri 2023-09-08 update*\ Copyright Assigment Form posted [here](/conference/call-for-papers#copyright-assignment-form) {% endhint %} {% hint style="success" %} *Thu 2023-08-31 update*\ Information about the pre-conference short course is now available [here](/program/preconference-professional-short-course) {% endhint %} {% hint style="success" %} *Tue 2023-08-08 update*\ We’re pleased to announce that abstracts for all full papers and abstract-only submissions have been published:\ [Full-paper submissions](/submissions/papers) // [Abstract-only submissions](/submissions/abstract-only) {% endhint %} {% hint style="success" %} *Fri 2023-07-28 update*\ Conference early bird registration closing 2023-07-31 >> [REGISTER NOW HERE](/conference/registration) {% endhint %} {% hint style="success" %} *Thu 2023-04-20 update*\ Conference and professional course registration with early bird pricing now open [here](/conference/registration) {% endhint %} {% hint style="success" %} *Tue 2023-04-18 update*\ Paper template now available on the Submissions page [here](#templates) {% endhint %} {% hint style="success" %} *Thu 2023-03-09 update*\ We are excited about two conference updates\ \ **Technical tour** // [Military Institute of Automotive and Armour Technology](https://www.witpis.eu/pl/), Sulejówek, near Warsaw. The tour will include a short presentation, visiting outdoor laboratories, and a presentation of test stands and vehicles. The tour will be followed by a visit to [Kazimierz Dolny](https://www.kazimierz-dolny.pl/turystyka/), with an opportunity for sightseeing and dinner in a restaurant.\ \ **Pre-conference short course — Elements of off-road vehicle design, dynamics, and terramechanics** // The Lublin conference committee has scheduled a one-day technical course to precede the conference, on October 10. Confirmed presentation on *Off-Road Vehicle Design Fundamentals* by [Dr. Zbigniew Kiernicki](https://scholar.google.com/scholar?hl=pl\&as_sdt=2007\&as_vis=1\&q=Zbigniew+kiernicki\&btnG=), Lublin University of Technology, Poland, and other presenters to be announced.\ \ ~~**Deadline for submissions** // Next week, March 15.~~ [~~Submit now~~](https://easychair.org/conferences/?conf=istvs2023)~~.~~\ Deadline for submissions now Thu 2023-03-30 *(updated Thu 2023-03-16)* {% endhint %} # Overview 16th European-African Regional Conference of the ISTVS ## Preconference | 10. October 2023 **10.00 – 15.00 |** [**Pre-Conference Professional Short Course**](#preconference-or-10.-october-2023)**, Room M107, R302** **14.00 – 17.00 | ISTVS Board of Directors Meeting, Room M107** **18.00 – 21.00 | Ice Breaker Welcome Event,** [**Hotel Ibis Styles**](https://ibislublin.pl/hotel/o-hotelu) **(15 mins by bus)** ## Conference Day 1 | 11. October 2023 **8.00 | Registration** **9.00 | Opening ceremony,** [**Auditorium A1**](https://www.google.com/maps/place/Wydzia%C5%82+Mechaniczny+Politechniki+Lubelskiej/@51.2368636,22.5494581,18z/data=!4m6!3m5!1s0x47225770dc9116cf:0xe36065c3b66c0cf!8m2!3d51.236872!4d22.550075!16s%2Fg%2F1203nl7st?entry=ttu)\ Conference Chair Welcome — Jarosław Pytka\ President’s Address — Corina Sandu\ Journal of Terramechanics Editor-in-Chief’s Address — Vladimir Vantsevich **10.00 | Plenary Session, Auditorium A1**\ Keynote: Prof. Jerzy Lipiec, Institute of Agrophysics, Poland\ \&#xNAN;*Vehicular traction effects on agriculture: Soil compaction and soil erosion, crop yield.* \ *Implications from the perspective of terramechanics* **12.00 | Conference photo followed by lunch in** [**Lanczomania**](https://www.google.com/maps?ll=51.235072,22.547164\&z=17\&t=m\&hl=pl\&gl=PL\&mapclient=embed\&q=Nadbystrzycka+40A+20-619+Lublin) **13.00 | Parallel sessions — 3 tracks — Auditorium M107/CT302/R302**
Autonomous and robotic systems

Chair: Dr Lutz Richter

Room: M107

Soil compaction I



Chair: Prof. Junya Yamakawa

Room: CT302


Off-road vehicle dynamics


Chair: Prof. Schalk Els

Room: R302

0274 / Deep learning method for IMU-based tracking of Martian rover
2177 / Effects of road wheel load, driving speed and track slip upon stress state in sandy soil under tracked vehicle loading
3859 / Analysis for dynamic characteristics of a tractor cabin during agricultural operations
0709 / Proposal of swarm rovers’ collaborative locomotion with expansion and contraction mechanism for driving a loose slope
2297 / Traction effects on vertical and horizontal contact stresses and the risk of soil structure deformation
4141 / Modeling and verification of a full-scale forestry vehicle real-time multi-physics digital twin
0889 / Skidding suppression method using “discrete 4-wheel-drive typed rover” considering steering angle at traveling across loose slope
3797 / Disturbed and naturally recovered soil surface as a ground for subsequent vehicle mobility operations
5356 / Development and validation of head-feeding combine harvester multibody dynamics simulation model
1453 / Suppressing the reduction of the traveling displacement on loose soil for rovers with the function of a wheel walking
4895 / Theoretical analysis and fem simulation of the interfacial forces between tracked vehicle and snow soil
6955 / Development of dynamics simulation model for agricutural tractor according to agricultural work
2765 / Obstacle detection vision system enabling autonomous mounding on clearcuts
6690 / Comparative evaluation of methods to evaluate penetration resistance for Clegg hammer and cone penetrometer
7198 / Analysis of aircraft dynamics while overcoming obstacles on a grass runway
8963 / Analysis of the influence of terrain unevenness and velocity on the ground pressure
**14.30 | Break** **15.00 | Parallel sessions — 3 tracks — Auditorium M107/CT302/R302**
Autonomous and robotic systems II

Chair: Prof. Genya Ishigami

Room: M107

Chair: Prof. Genya Ishigami

Room: M107

Propulsion systems and engines

Chair: Prof. Rafał Longwic

Room: CT302

Chair: Prof. Rafał Longwic

Room: CT302

Driving systems of off-road vehicles and machines

Chair: Massimo Martelli

Room: R302

6027 / Digital precision planning tool for autonomous forest regeneration of mixed tree species
4816 / Effects of humidity on the emissions of the diesel engines
2437 / Improving predictive control methods on off-road vehicles with realistic steering preview inputs
8151 / Study on estimation of traveling states using strain information on chassis of lunar and planetary exploration rovers
7477 / Evaluating the pressure performance of DPF filters using engine bench analysis
3815 / Data measurement and performance evaluation of an electric all-wheel-drive tractor during plow tillage
8672 / Trajectory optimization for vegetation override in off-road driving
1166 / Selection of energy saving engine mode based on the power delivery and fuel consumption of a 95-kW tractor during agricultural operations
3893 / Analysis of load factor and performance evaluation for developing an electric driven tractor
2145 / Obstacle performance and wheel failure test analysis of Zhurong rover
4727 / Analysis of gear durability for agricultural tractor transmission4727 / Analysis of gear durability for agricultural tractor transmission
8254 / Characterization of the new US army cold weather all-terrain vehicle (CATV) on winter surfaces
4976 / Performance evaluation of autonomous driving lateral control simulation model of agricultural tractor
**16.30 | Break** **17.00 | LUT Off-Road and Military Vehicle Students‘ Projects — Workshop, Prof. L. Gardyński** ## Conference Day 2 | 12. October 2023 **9.00 | Plenary session, Auditorium A1**\ Keynote: Stelios Skevakis, Hellenic Technology of Robotics, Greece\ \&#xNAN;*A novel flexible all-metal wheel for planetary exploration* **9.45 | Plenary session, Auditorium A1**\ Keynote: Dr Andrzej Selenta, Warsaw University of Technology, Poland\ \&#xNAN;*The Bekker Project* **10.30 | Parallel sessions — 3 tracks — Auditorium M107/CT302/R302**
Off-road mobility modeling I


Chair: Prof. Corina Sandu

Room: M107

Soil characterization I



Chair: Prof. Peter Kiss

Room: CT302

Metrology in terramechanics


Chair: Prof. Jerzy Józwik

Room: R302

6211 / Wheel-soil terramechanics model augmentation using machine learning across multiple soil types
1098 / Simulation of change in supporting force when imparting vibration by distinct element method
1638 / Analysis of tire characteristics on road surface with volcanic ash fall
1522 / Tractive performance of rigid wheel in granular media using coarse-scale DEM models
2801 / In Situ Soil Property Estimation for Autonomous Earthmoving Using Physics- Infused Neural Networks
1779 / The development of a dynamic vegetation override pushbar for autonomous ground vehicles
6143 / Flexible tire-terrain interaction model for real time simulations
4336 / High-fidelity 3D-DEM simulation for wheel mobility in low gravity environment
4595 / Evaluation and comparison of driving performance of a lunar exploration rover wheel in different soils
3835 / Effect of steer angle rate upon tyre lateral force generation on two different soils
4456 / Modeling soil-tool interaction of a cultivator sweep using DEM
5552 / Vehicle drawbar test method with improved measurement and control
4508 / Semi-empirical terramechanics model for variable terrain height
6861 / Researches on airplane performance on a grass airfield
**12.00 | Lunch in Lanczomania** **13.00 | Parallel sessions — 2 tracks — Auditorium M107/R302**
Off-road mobility modeling II

Chair: Prof. Jozsef Koveceses

Room: M107

Soil characterization II

Chair: Tomohiro Watanabe

Room: R302

3796 / The issue of assessing the suitability of own simulation models for testing off-road vehicles
2936 / Moisture content impacts on soil load bearing capacity and its spectral behaviour
6736 / Ride comfort comparison between 4-poster and straight line driving simulations
3493 / Numerical modeling of a tire on undrained saturated clay using FEM, ALE, and SPH
0448 / Lunar rover discrete element method study and calibration
9992 / Soil shear strength values obtained from its colour
8859 / An efficient and high-fidelity track model for dynamic simulation of off-road tracked vehicles
7577 / Implementation of moving loads on ice in NRMM
4681 / Simplified models of terrain-vehicle interaction for real-time applications
1805 / Accelerating graph networks for real-time physics simulations
**14.30 | Break** **15.00 | Parallel sessions — 2 tracks — Auditorium M107/R302**
Soil compaction II


Chair: Dr Loraine ten Damme

Room: M107

Chair: Dr Loraine ten Damme

Room: M107

Innovative concepts of tires, wheels, and tracks

Chair: Prof. Przemysław Simiński

Room: R302

7523 / Assessing performance of light wheeled vehicles on GRC-1 using 3D scanned footprint measurements
3280 / Comparison of tweels and pneumatic tires on LTATV military vehicle
8754 / Characterization of lunar simulant (FJS-1), toyoura sand, and silica sand with physical experiments and dem simulation
6059 / Comparison of multi-tracked running gears for light UGVs in terms of terrain obstacles overcoming abilities
9504 / Soil deformation model for efficient simulation of off-road vehicles and compaction force analysis
7994 / Longitudinal friction coefficient comparison on actual and laboratory surfaces
3507 / Determination of the tractive forces of a tractor based on the reconstruction of tire – soil contact surface obtained by means of photogrammetry
9268 / Experiments of singkage characters of wire mesh wheel under different slip ratio
6630 / Real-time measurement of tire sinkage using stereo cameras
9716 / Non-pneumatic tire for special vehicle – a review of selected functional properties
**16.30 | Closing ceremony and awards** **19.00 | Gala dinner —** [**Hotel Ibis Styles**](https://ibislublin.pl/hotel/o-hotelu) ## Conference Day 3 | 13. October 2023 [Technical Tour — Sulejówek](/conference/technical-tour) 7.30 | Departure 10.00 | Arrival at [WITPIS Sulejówek](https://www.witpis.eu/pl/) 10.15 | Welcome by MIAAT officer and a short presentation of the programme 10.20 | Presentation of the Institute (indoor) 10.35 | Presentation of the laboratories (outdoor/indoor, talk to test engineers/researchers) 11.30 | Test-show of military vehicles: Jelcz, Tareo, Rosomak (outdoor, in action) 13.00 | Refreshments (Military pea soup + coffee/tea) 13.30 | End and farewell to the participants of the trip 14.00 | Departing from Sulejówek 15.30 | [Kazimierz Dolny](https://www.kazimierz-dolny.pl/turystyka/), lunch in a restaurant 16.00 | Visiting Kazimierz Dolny 18.00 | Departing for Lublin ## Student Projects Workshop Hands-on demonstrations of Lublin University of Technology student projects in off-road and military vehicles will be ongoing through the conference. Here are a few examples. [See all the projects that will be on display](/program/student-projects). ### Off-Road and Military Vehicles | Lublin University of Technology

BUGGY 4x4. A prototype of a light off-road vehicle with improved trafficability and versatile use proposed by the Lublin University of Technology for the army and public order services.

ŻUK 6x6. A small tipper with all-wheel drive and the possibility of configuring the drive 6x2, 6x4, and 6x6. Has a cab that opens like in larger trucks and other improvements for off-road use.

HYBRID POLONEZ Students installed an additional axle. Steel tracks are mounted on the wheels of the two rear axles and skids on the front axle wheels, thanks to which the vehicle is able to overcome snowy areas.

# Preconference Professional Short Course October 11, 2023 | Lublin, Poland ## Design and Dynamics of Off-Road Vehicles with Emphasis on Terramechanics ISTVS invites a limited number of attendees to explore the design and dynamics of off-road vehicles with a special emphasis on terramechanics. Three speakers — remarkable researchers and educators — will deliver 90-minute lessons on crucial aspects of vehicle design, testing, and dynamics for innovative solutions in the field of off-road dynamics, safety, and comfort. The course content has a deep reference to both classical and upcoming innovations in terramechanics. Number of attendees is limited.\ Available as an add-on to your conference registration or register separately for the course. ### Preconference Professional Short Course Registration ​[🎟 2023 Professional Short Course Registration | Members EUR 100](https://buy.stripe.com/5kA8wL29t6d27SwbIQ) [🎟 2023 Professional Short Course Registration | Non-Members EUR 150](https://buy.stripe.com/5kA8wL29tgRGb4IbIR) ### When Tuesday, October 10, 2023, 9.50 – 15.00 ### Where Lublin University of Technology\ Faculty of Mechanical Engineering, Room M107 ### Program Welcome // 9.50 – 10.00 **1 // Novel Methods in Analytical and Experimental Off-Road Vehicle Dynamics** | 10.00 – 11.30\ Schalk Els, University of Pretoria, South Africa The analysis and testing of off-road vehicle dynamics have changed significantly over the past decades due to new testing and modelling technologies. This lecture will summarize new developments in equipment for testing of large off-road tyres and tyre-terrain interaction, including wheel force transducers, static and dynamic test rigs as well as the use of cameras for measuring slip angle, rut depth and tyre deformation. The use of steering and pedal robots, as well as testing multiple vehicle interactions for collision avoidance system development will also be addressed. This includes testing in GPS denied environments such as underground mines. **2 // Elements of Planetary Rover Design: Innovative Solutions for Optimal Traction on Extraterrestrial Bodies** | 11.45 – 13.15\ Lutz Richter, SoftServe, Inc., Munich, Germany This talk outlines key topics in sizing and design of mobility systems for rovers for the Moon and other planets, in particular from the point of view of terramechanics. The overall discipline of planetary surface robotics involves a mix of technology domains, being i) *mechatronics* (electro-mechanical systems), ii) *soil-machine interaction* (the science of terramechanics), and iii) *autonomy*, the latter due to the lack of broadband, real-time remote control of planetary robots from Earth. [Full description](/program/preconference-professional-short-course/elements-of-planetary-rover-design). **3 // New Trends in Off-Road Vehicle Design** | 13.30 – 15.00\ Zbigniew Kiernicki, Lublin University of Technology, Poland The design of off-road vehicles has changed significantly over the past decades due to new uses and fashions. New types of off-road vehicles have appeared. This lecture will present the development of off-road vehicle classification. The distinguishing features of different classes of off-road vehicles will be discussed. Examples of new design solutions for individual vehicle subassemblies will be presented, which illustrate the directions of development of off-road vehicle construction. Technical parameters of current off-road vehicles will be presented. # Elements of Planetary Rover Design Innovative Solutions for Optimal Traction on Extraterrestrial Bodies **2 // Elements of Planetary Rover Design: Innovative Solutions for Optimal Traction on Extraterrestrial Bodies** | 11.45 – 13.15\ Lutz Richter, SoftServe, Inc., Munich, Germany This talk outlines key topics in sizing and design of mobility systems for rovers for the Moon and other planets, in particular from the point of view of terramechanics. The overall discipline of planetary surface robotics involves a mix of technology domains, being i) *mechatronics* (electro-mechanical systems), ii) *soil-machine interaction* (the science of terramechanics), and iii) *autonomy*, the latter due to the lack of broadband, real-time remote control of planetary robots from Earth. Full description. We are currently witnessing a surge of new rover missions, primarily because of commercial actors that now are developing rovers for technology demonstrations and science on the Moon and that range in mass between \~1 kg to \~50 kg. NASA at the same time is developing its first lunar rover since the APOLLO LRV, being the \~430 kg VIPER vehicle. China has been the only nation to have successfully landed and operated rovers on the Moon in the modern spaceflight era, having been the \~140 kg YUTU rovers on CHANG#E 3 and 4. On Mars, successful rover missions have been continuing over the last >20 years, including the Chinese ZHURONG rover and NASA’s PERSEVERANCE geoscience and sample caching rover (being part of Mars Sample Return). A variety of performance metrics apply to the sizing of lunar and planetary rovers, mandating sound predictive models of the vehicle interaction with the terrain during the design phase. This begins with an assessment of the type of running gear (wheels, legs, tracks) and the type of suspension for handling geometric obstacles and to equalize load imposed on the terrain. Related trade-offs nowadays are performed primarily via simulations but in the past much relied on testing of prototypes. Historically, the principles of terrestrial terramechanics have already been successfully applied to planetary rover sizing and development, most notably semi-empirical “Bekker-type” models that provided the basis for the NASA Apollo Lunar Roving Vehicle (LRV) predictive model for traction and drawbar pull which correlated extremely well with measured energy consumption during the missions. The Russian approach for the LUNOKHOD rovers on the other hand has been based more on tests on Earth, building up a database subsequently used for mission predictions, likewise correlating very well with mission data on gradeability and gross pull vs. slip. For the US Mars rovers of today, different approaches were used, most recently coupling of a multibody simulation model of the vehicles with a semi-empirical wheel-soil interaction model, very well reproducing mission data in terms of wheel motor currents and wheel sinkage. In China, semi-empirical models validated by single wheel tests were applied to the design of the wheels for the YUTU lunar rovers and the ZHURONG rover of China’s first Mars mission TIANWEN-1. In Europe, both semi-empirical and analytical models have been developed in support of various planetary rover projects, most notably the ExoMars mission. The semi-empirical model (TPM) for the ExoMars metallic flexible wheel correlates well with single wheel tests on Mars soil simulants. In general, correlation of planetary rover mobility models with mission data is difficult to achieve, not because the models are peculiar or unusual but because instrumentation on the spaceflight systems is too rudimentary for a comprehensive model validation, due to difficulties in qualifying the required sensors (such as load cells and torque sensors) for the space environment (radiation, vacuum, temperature ranges). A particular challenge in rover mobility system development is mobility testing at Earth gravity, as the difference in gravity not only modifies vehicle weight but also the properties of the terrain that is traversed. New trends in planetary rovers are aimed at improving autonomy and operational robustness, to minimize chances of immobilization in weak terrain. Countermeasures now part of modern rover concepts and designs include active or “hybrid” suspensions, real-time slip estimation for the wheels, and on-board torque / slip control (pioneered on the NASA CURIOSITY Mars rover for protecting the life of its wheels). In the future, torque and slip control can also be aided via appropriate sensors that may be embedded inside the wheels. Another recent improvement is the implementation of real-rime stereo vision for faster recognition of geometric obstacles – while driving – and thus faster overall traverses, as demonstrated on the NASA PERSEVERANCE Mars rover. # Student projects Lublin University of Technology Among numerous student technical groups at the Lublin University of Technology, there is the Student Group of Materials Engineering, led by Prof. Leszek Gardyński, who is also a great enthusiast of off-road and military vehicles. Prof. Gardyński, together with students of mechanical engineering, create designs for various off-road vehicles and machines. Selected projects are presented below. All of these vehicles will be available to conference attendees on October 11. The presentation of these vehicles will be located at the main entrance to the RUSTY building. Students who participated in the construction will be present with each vehicle and will be happy to explain the details to the conference attendees. From 5.00 PM there will be a presentation of the vehicles, during which they will be launched and presented in action. More information on individual vehicles can be obtained through the chair of the conference, Jarosław Pytka

BUGGY 4x4. A prototype of a light off-road vehicle with improved trafficability and versatile use proposed by the Lublin University of Technology for the army and public order services.

ŻUK 6x6. A small tipper with all-wheel drive and the possibility of configuring the drive 6x2, 6x4, and 6x6. Has a cab that opens like in larger trucks and other improvements for off-road use.

HYBRID POLONEZ Students installed an additional axle. Steel tracks are mounted on the wheels of the two rear axles and skids on the front axle wheels, thanks to which the vehicle is able to overcome snowy areas.

Tracked mower. A small mower with a tracked running gear and equipped with two motors, one to drive the tracks, the other to drive the mowing knives.

TRABAKTOR Zbyszek. A nice and very practical tractor based on parts from Trabant and Polonez cars among others.

RYSIEK 8x8. A remotely controlled off-road platform based on the idea of ​​Ryszard Pluciński from Podhale, Poland. An articulated vehicle that can be used for a variety of purposes.

RUDY 105B. A ​​universal tracked vehicle of 1 tonne class. Various superstructures can be mounted on the vehicle. Currently, presented adapted and rebuilt into a military off-road style with a Syrena 105 Bosto body.

# Lublin Young Volunteers Program New in this year’s ISTVS conference is the young volunteers program. Teenagers from Lublin high schools have the opportunity to participate in the organization of the conference by helping during the event. It is an opportunity to establish interpersonal contacts, generate interest in science and research — and especially terramechanics — and learn how to organize and perform a scientific conference. Interested young volunteers are asked to complete the online form below. This initiative refers to Lublin - European Youth Capital 2023 program Additionally, it is required to attach a completed and signed consent form from parents/legal guardians: {% file src="/files/SlYlxnwjPua7HhmZDZlk" %} Registered participants will be instructed on volunteering activities by the conference chair in the week preceding the conference. {% embed url="" %} # Call for Papers 16th European-African Regional Conference of the ISTVS {% hint style="warning" %} *Mon 2023-10-02 update*\ Presentation Template posted [below](#presentation) {% endhint %} The 16th European-African Regional Conference of the ISTVS welcomes original and previously unpublished research and review papers describing results of research which are relevant to the conference topics and to terrain-vehicle systems. * Authors wishing to make a submission are requested to submit an abstract by March 15, 2023. * Abstracts are requested to be under 1800 characters and must emphasize the objectives and results. * Authors may choose between two types of submissions: \ full paper and abstract-only. All accepted submissions of either type will be included in the conference program for an oral presentation. Only full papers will be included in the conference proceedings. If your abstract is accepted, we strongly encourage you to submit a full paper in order to be included in the published proceedings. **Review** // All abstracts will be reviewed by the conference Scientific Committee. Abstract acceptance will be notified to the corresponding author by March 15, 2023. ### **Technical tracks** The conference includes the following thematic tracks: * soil mechanical characterization * off-road mobility modeling * soil compaction * driving systems of off-road vehicles and machines * innovative concepts of tires, wheels, and tracks * propulsion systems and engines * vetronics * autonomous and robotic systems * metrology in terramechanics
### **Submission platform** As in previous years, the conference submission platform is [EasyChair](https://easychair.org/conferences/?conf=istvs2023). If you’ve participated in a recent ISTVS conference, you will be able to log in with your existing account. If you’re new to ISTVS conferences, use the *Create an account* link on the login page to get started. \ **Access here:** [**https://easychair.org/conferences/?conf=istvs2023**](https://easychair.org/conferences/?conf=istvs2023)

RrSubmissions login page for ISTVS 2023

### Copyright Assignment Form Copyright assignment form is intended for original material submitted to conferences of the International Society for Terrain-Vehicle Systems (ISTVS) and must accompany any such material in order to be published by the ISTVS. Before publication of your paper in conference proceedings, the ISTVS must receive a completed and signed copy of this form sent via email to the conference chair. {% file src="/files/Uui34eRKsqNyYQ4UMiVo" %} ISTVS Copyright Assigment Form 2023.pdf {% endfile %} ### **Templates** All submissions must comply with the conference templates. Please carefully follow the guidelines provided. Right-click the links below to download: Template for Abstract *// use* [*EasyChair submission form*](https://easychair.org/conferences/?conf=istvs2023)\ Template for Full Paper *// posted 2023-04-18* {% file src="/files/wjU55jBqNkSBkwzYxSx4" %} ISTVS\_paper\_template\_2023 combined .dotx and reference.pdf {% endfile %} ***REFERENCE PDFs***\ \&#xNAN;*Provided for reference since live docs often open locally with broken formatting.* **Paper preparation** // Authors submitting a full paper must comply with the conference template and carefully follow the guidelines provided. Each full paper will be subject to peer review by reviewers selected by the Conference Scientific Committee. Each paper will be either accepted or accepted with revisions or rejected. ### **Presentation** At least one author of a paper must attend the conference to present. If the full paper is not presented at the conference, it will not be included in the conference proceedings. Template for Presentation *// posted 2023-10-02* {% file src="/files/IcrF94FT6ZB5O0UhWlaq" %} ISTVS 2023 Presentation Template .pptx {% endfile %} {% hint style="warning" %} *Fri 2023-09-08 update*\ Copyright Assignment Form posted [below](#copyright-assignment-form) {% endhint %} {% hint style="warning" %} *Tue 2023-04-18 update*\ Paper template posted [below](#templates) {% endhint %} {% hint style="success" %} *Thu 2023-03-16 Update*\ Submissions deadline now extended to Thu 2023-03-30. [Submit here](https://easychair.org/conferences/?conf=istvs2023). {% endhint %} {% hint style="success" %} *Thu 2023-01-26 Update*\ Submissions open February 14, 2023. All authors are encouraged to submit full papers. Abstracts for oral presentations may also be submitted. {% endhint %} # Registration 16th European-African Regional Conference of the ISTVS {% hint style="success" %} *Wed 2023-10-04 update / Registration links for accompanying guests published:* [*🎟* Ice Breaker Welcome Event | EUR 50 per guest](https://book.stripe.com/6oE14j6pJeJyfkYdR0)\ The always popular conference kick-off. Tuesday evening, October 10, at [Hotel Ibis Styles](https://ibislublin.pl/hotel/o-hotelu) *​🎟* [Gala Dinner | EUR 65 per guest](https://book.stripe.com/28o9APaFZ30QdcQ8wH)\ Closing event of the conference, Thursday evening, October 12, at [Hotel Ibis Styles](https://ibislublin.pl/hotel/o-hotelu) {% endhint %} {% hint style="success" %} **Mandatory Author Registration Requirements** // ISTVS author registration policy requires that at least one author from each accepted (accepted with revisions) paper be registered and paid prior to the uploading of the final manuscript before August 31, 2023. {% endhint %} {% hint style="success" %} **Cancellations** // Any cancellation request must be made in writing and submitted to the Conference Chair no later than August 1, 2023. A processing fee will be applied to all refund requests. Refunds are NOT permitted on/after September 1, 2023. {% endhint %} #### Registration To register now online by credit card, use the registration choices below to choose the appropriate registration, then complete the checkout process on the payment page. ISTVS partners with Stripe for simple and safe online payments. All prices are in EUR. #### **Conference Registration After 31 July 2023** ​🎟 [2023 Registration | Members EUR 500](https://buy.stripe.com/eVaeV9g0j6d2b4I9AC) ​🎟 [2023 Registration | Non-Members EUR 600](https://buy.stripe.com/28o14j15p44U8WA4gk) ​🎟 [2023 Registration | Students EUR 250](https://buy.stripe.com/4gw5kzaFZ7h6b4IbIN) #### Professional Short Course Registration | [Course details](#professional-short-course-registration-or-details) ​[🎟 2023 Professional Short Course Registration | Members EUR 100](https://buy.stripe.com/5kA8wL29t6d27SwbIQ) [🎟 2023 Professional Short Course Registration | Non-Members EUR 150](https://buy.stripe.com/5kA8wL29tgRGb4IbIR) #### **Registration of accompanying guests** The conference is open to accompanying guests. If you are bringing one or more guests, please select one of the following options during the registration process below. [*🎟* Ice Breaker Welcome Event | EUR 50 per guest](https://book.stripe.com/6oE14j6pJeJyfkYdR0)\ The always popular conference kick-off. Tuesday evening, October 10, at [Hotel Ibis Styles](https://ibislublin.pl/hotel/o-hotelu) *​🎟* [Gala Dinner | EUR 65 per guest](https://book.stripe.com/28o9APaFZ30QdcQ8wH)\ Closing event of the conference, Thursday evening, October 12, at [Hotel Ibis Styles](https://ibislublin.pl/hotel/o-hotelu) #### Additional open events *​🎟* Technical tour to [the Military Institute of Armored and Automotive Technology (MIAAT)](https://witpis.pl/english-2/witpis-home-cloned/) Sulejówek, Friday, October 13. Meals at the restaurant to [Kazimierz Dolny](https://www.kazimierz-dolny.pl/). Participation is free of charge. *​🎟* Practical demonstrations of student projects of Lublin University of Technology in the field of off-road and military vehicles will continue during the conference. Participation is free of charge. #### ***Early Bird Conference Registration before 31 July 2023*** *​🎟 2023 Early Bird Registration | Members EUR 450* *​🎟 2023 Early Bird Registration | Non-Members EUR 550* *​🎟 2023 Early Bird Registration | Students EUR 200* #### # Location 16th European-African Regional Conference of the ISTVS ## Lublin University of Technology [Lublin University of Technology](https://pollub.pl/) is the largest technical university in the region of eastern Poland. It has a 70-year tradition and consists of six faculties. {% embed url="" %} [The Faculty of Mechanical Engineering](https://wm.pollub.pl/) strives to carry out scientific research at the highest level, aimed at the needs of industry, enabling its employees and doctoral students to develop comprehensively, based on the best standards, equipment, tools and methods. The mission of the Faculty of Mechanical Engineering is interdisciplinary education of students in a way that ensures the acquisition of knowledge and skills to create creative solutions, in conjunction with science, technical development, in cooperation with the economy and society and in accordance with the best international standards and the level of modern civilization.

Lublin University of Technology

## Lublin Here is some information about the city: * [Young at heart: Poland’s party city of Lublin | Poland holidays | The Guardian](https://www.theguardian.com/travel/2023/jul/01/young-at-heart-polands-party-city-of-lublin-european-youth-capital) * [European Youth Capital 2023](https://lublin.eu/en/lublin/youth-lublin/) * [Carnaval Sztukmistrzów | Edition 2022 - YouTube](https://www.youtube.com/watch?v=opvoK6hBqrY) ## Travel to Lublin, Poland * Air transfer through Warsaw (general international connections), Rzeszów, and Cracow (south connections) or directly to Lublin Airport, * Transfer from Warsaw: by train (approx. 2h30m) , by coach (approx. 2h), , ## Public transport in Lublin * Modern public transport network, electric buses, convenient connections * Individual transport: taxi, Uber, Bolt, electric scooter network * Rental cars: [https://www.rentalcars.com](https://www.rentalcars.com/pl/city/pl/lublin/?affiliateCode=ggle\&preflang=pl\&label=lublin-m_4RTyPMwzVDRay8MGD73QS263768963943\&ws=\&ppc_placement=\&ppc_target=\&ppc_param1=\&ppc_param2=\&aceid=\&adposition=\&ppc_network=g\&feeditemid=\&ppc_targetid=kwd-115099250687\&loc_physical_ms=9067423\&loc_interest_ms=\&ppc_device=c\&ppc_devicemodel=\&gclid=Cj0KCQiAlKmeBhCkARIsAHy7WVuWg3MGZFVvGopqss3yPP2T9zrduGqwZTdHOcahCoAU7UrvUREk1_gaAt25EALw_wcB), , ## Hotel information—selected hotels *Times given in walking distance from conference venue* Hotel Victoria Lublin, 10 min.\ IBB Grand Hotel Lublin, 15 min.\ Hotel Mercure Lublin, 20 min.\ **Gala dinner venue:** Ibis Styles Hotel Lublin, 20 min.\

Gala Dinner Venue

# Technical tour 16th European-African Regional Conference of the ISTVS The 2023 16th European-African Regional Conference of the International Society for Terrain-Vehicle Systems (ISTVS) will conduct a technical tour at [the Military Institute of Armored and Automotive Technology (MIAAT)](https://witpis.pl/english-2/witpis-home-cloned/) located at the Sulejówek, near Warsaw. The tour will include a short presentation, visiting outdoor laboratories, and a presentation of test stands and vehicles. The tour will be followed by a visit to [Kazimierz Dolny](https://www.kazimierz-dolny.pl/), with an opportunity for sightseeing and dinner in a restaurant.
> The Military Institute of Armored and Automotive Technology (MIAAT) is a facility where research and development projects are conducted to improve the quality and functionality of vehicles, military equipment and armaments of the Polish Army.

SANP

BORSUK

> MIAAT conducts research and tests of vehicles implemented in the Polish Armed Forces and participates in the process of their modernization. Meeting the growing demand for new technologies, the Institute is involved in research, the results of which carry considerable potential for implementation and innovation. Performing work in the area of research, development and implementation of military and civilian equipment, the Institute participates in many key R\&D project on a national and international scale. > > The Institute has three accredited laboratories, a Product Certification Unit, an Expert Office and, above all, qualified staff, which allows to cooperate with many universities in terms of research projects, joint publications and the development of scientific staff.\ > \- MIIAT website ### Schedule for October 13, 2023 7.30 Departure from Lublin\ 10.00 Arrival at [MIAAT Sulejówek](https://witpis.pl/english-2/witpis-home-cloned/)\ 10.15 Welcome by MIAAT officer and a short presentation of the programme\ 10.20 Presentation of the Institute (indoor)\ 10.35 Presentation of the laboratories (outdoor/indoor, talk to test engineers/researchers)\ 11.30 Test-show of military vehicles: Jelcz, Tareo, Rosomak (outdoor, in action)\ 13.00 Refreshment (Military pea soup + coffee/tea)\ 13.30 End and farewell to the participants of the trip\ 14.00 Departing from Sulejówek\ 15.30 [Kazimierz Dolny](https://www.kazimierz-dolny.pl/), lunch in a restaurant\ 16.00 Visiting Kazimierz Dolny\ 18.00 Departing for Lublin ### Registration details *Registered conference attendees:* the cost to attend the technical tour is already **included** in the conference registration fee. *Registered accompanying guests*: must book the tour **separately** (see details in [**Registration**](/conference/registration)) In either case, not later that **Friday, 15 September 2023**, you must submit the dedicated **registration form** (below), uploading a scan of a valid **identity document**, so that the necessary background checks can be carried out. Accepted identity documents are: 1. Polish and EU citizens: National Identity Card or Passport. 2. Non-EU citizens: Passport. Please take notice of the following: 1. **Attendees who do not submit all the required information within the given deadline will not be authorized to attend the tour.** 2. **Final authorization is dependent on successful background checks.** 3. **The MIAAT reserves the full right to reject any technical tour registration request.** #### Technical Tour Additional Information The technical tour to MIAAT facilities will take place on Friday, 13 October 2023. Registered tour attendees will meet outside (east gate) the RUSTY-Building on the campus of the Lublin University of Technology at 7:15 and board buses for transportation to MIAAT facilities. Buses depart from RUSTY promptly at 7:30. Upon completion of the tour at MIAAT, the buses will transfer attendees to Kazimierz Dolny for lunch and visiting the city. After visiting Kazimierz Dolny, buses will return attendees to Lublin, finishing the ride at RUSTY-Building of the LUT. ### Registration form *Note: scroll to show Register button again after uploading your image.* {% embed url="" %} {% hint style="success" %} *Note that you will not receive a confirming tour registration email.* {% endhint %} # Statement on Publication Ethics and Malpractice for the 16th European-African Regional Conference of the ISTVS ## A. Publication and authorship 1. All manuscripts submitted to 16th European-African Regional Conference of the ISTVS (hereinafter the Conference) are subjected to strict peer-review process by at least two independent reviewers that are experts in the field of the submitted paper. Acceptance is based on scientific significance, originality, and clarity. 2. The factors that are taken into account in review are relevance, soundness, significance, originality, readability, and language. 3. Based on the reviewers’ comments, a decision (*acceptable in the present form; acceptable with revision; reject*) is made by the members of the Conference Scientific Committee in charge of the review process. At the end of the review process, the Conference Chair makes the final decision. 4. If authors are encouraged to revise and resubmit a manuscript, there is no promise made or commitment given that the revised manuscript will be accepted. 5. Rejected manuscripts will not be re-evaluated. 6. Only manuscripts that are not tainted by libel, copyright infringement, and plagiarism are eligible to be accepted. ## B. Authors’ responsibilities 1. Authors must ensure that the manuscript is entirely their original work, that the manuscript has not previously been published elsewhere, and that the manuscript is not currently being under consideration for publication elsewhere. 2. Authors must participate in the peer review process. 3. If at any point in time the authors discover a significant error or inaccuracy in the submitted manuscript, they are obliged to report the error or inaccuracy to the editor immediately. 4. Every author listed in the manuscript must make a significant contribution to the conception, design, execution, or interpretation of the reported study. Authors must also ensure that all the authors have seen and agreed to the submitted manuscript and their inclusion as co-authors. 5. Authors must provide a proper description of the sources and methods used to obtain and analyze data. 6. Authors must notify the editors of any conflicts of interest. 7. Authors must ensure that the manuscript has been proofread and corrected for clarity, grammar, and spelling of the text. ## C. Reviewers' responsibilities 1. Reviewers should respect the confidentiality of peer review and not reveal any details of a manuscript during or after the peer-review process. 2. Reviewers should be objective and constructive, refraining from being hostile or inflammatory and from making libelous or derogatory personal comments. 3. Reviewers should evaluate the manuscript based on its suitability for the conference and its originality. Reviewers should also evaluate whether the manuscript has clear objectives, sound methods, and clear and sufficient results supporting the conclusions with appropriate figures, tables, and references. 4. Reviewers should report their review results clearly with supporting arguments. 5. Reviewers should notify the authors about any published work they deem relevant that has not been cited in the paper. 6. Reviewers should bring the editor’s attention to any substantial similarity or overlap between the manuscript under consideration and any other published paper of which they have personal knowledge. 7. Reviewers should not review manuscripts in which they have conflicts of interest resulting from competitive, collaborative, or other relationships or connections with any of the authors, companies, or institutions connected to the papers. ## D. Editors’ responsibilities 1. Editors are held accountable and should take responsibility for everything they allow to be published. 2. Editors must base their decisions solely on the papers’ importance, originality, clarity, and relevance to the conference’s scope, without regard to race, gender, sexual orientation, religious belief, ethnic origin, citizenship, or political orientation of the authors. 3. Editors must not share information about the manuscripts, including whether they have been received and are under review, their content and status in the review process, any criticism by reviewers, and their ultimate fate, to anyone other than the authors and reviewers. Editors must also make clear that reviewers should keep manuscripts, associated material, and the information they contain strictly confidential. 4. Editors must preserve the anonymity of the reviewers. 5. Editors must make sure that the funding source of the research is should be declared and published, and that the role of the funding source in the conception, conduct, analysis, and reporting of the research is stated and published. 6. Editors must not allow any conflicts of interest between editorial staff, authors, reviewers, and editorial board members. 7. Editors must guard the integrity of the publication by issuing corrections and retractions when needed and pursuing suspected or alleged research and publication misconduct. ## E. Plagiarism All articles submitted to the Conference must contain exclusively original research. Passing off another’s research as the author’s own, copying or paraphrasing substantial parts of another’s paper (without attribution), or claiming results from research conducted by others are all considered to be forms of plagiarism. Plagiarism in all its forms constitutes unethical publishing behavior and is unacceptable. ## F. Duplicate submission Authors should not submit for consideration a manuscript that has already been published in another journal or conference. Submission of a manuscript concurrently to more than one journal or conference constitutes unethical publishing behavior and is unacceptable. ## G. Data fabrication and falsification Authors should not include spurious data or false research results in the manuscript. Also, manipulation of the research process or the arbitrary alteration or omission of data which leads to the distortion of the contents or the results of the research should not be done. ## H. Citation manipulation Authors should not include citations whose primary purpose is to increase the number of citations to an author’s given article. ## I. Improper author contribution or attribution All listed authors must have made a significant scientific contribution to the study in the paper and approved all its claims. It is important to list everyone who made a significant scientific contribution, including students and laboratory technicians. ## J. Redundant publications The artificial division of study outcomes into multiple articles for the sole purpose of increasing the quantity of publications constitutes redundant publication is unethical publishing behavior and is unacceptable. Multiple papers generated from the same study can be accepted if they focus on different aspects of the study, in a sensible and meaningful way. ## K. Rejection of manuscripts In the case of unwillingness of the authors to cooperate with the Scientific Committee (e.g., refusing to improve the manuscript as requested or not having a proper communication with the Scientific Committee), the manuscript is rejected. A manuscript is rejected also in case of plagiarism, data fabrication, or falsification. # Contact 16th European-African Regional Conference of the ISTVS For all general inquiries with respect to the conference: **Jarosław Pytka**\ \&#xNAN;*Conference chair ::* [*j.pytka@pollub.pl*](mailto:undefined)\ [Faculty of Mechanical Engineering](https://wm.pollub.pl/) | [Lublin University of Technology](https://pollub.pl/) # Papers # 0274 / Deep learning method for IMU-based tracking of Martian rover Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Deep learning method for IMU-based tracking of Martian rover Authors: Paweł Tomiło Abstract: The double integration method is one of the most used techniques for calculating an object's position in time. As dynamic noise and bias can affect sensor data, filters like the alpha-beta filter or the Kalman filter are frequently utilized. They are in capable of compensating for sensor reading noise. The quality of the sensor has a big impact on how accurate these solutions are. When using inexpensive sensors, a correctly built neural network model can help compensate for noise and determinate the change in the position of the object over time. The article describes the method of tracking an RC vehicle using the low-cost IMU module and software consisting of an artificial neural network model specially developed for this purpose. Base stations that emitted infrared laser scans were utilized as a reference method to confirm the accuracy of the proposed solution and as a means of data collection for training. The proposed model provides acceptable accuracy when compared to the reference method. the tests were carried out on a short section of the road, in the case of longer sections the estimation error may be larger. The developed solution can be used as part of a larger system combined with visual odometry to navigate an autonomous vehicle. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 0448 / Lunar rover discrete element method study and calibration Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Lunar rover discrete element method study and calibration Authors: James Hurrell, Keisuke Takehana, Kentaro Uno, and Kazuya Yoshida Abstract: *Context.* The Discrete Element Method (DEM) is a high-fidelity simulation tool to study the interaction of granular material. The single-wheel interaction of a lunar rover wheel with Toyoura sand is studied. Traditionally Toyoura sand is considered cohesionless but is measured to have a cohesion similar to Lunar soil. Aims. Develop a well-calibrated DEM wheel-soil simulation with and without cohesion for an equivalent angle of repose (AoR). \ \&#xNAN;*Methods.* 3D DEM single-wheel simulations are performed for Toyoura sand in Earth conditions. Separate calibration for the simulation parameters uses AoR. The Johnson–Kendall–Roberts (JKR) model is used, allowing for particle cohesion modelling. Simulations are kept homogeneous and use spherical particles. A comparison is made between non-cohesive and cohesive simulations. Traction coefficient, wheel sinkage, wheel trace and soil flow under the wheel are measured. \ \&#xNAN;*Results.* The static friction coefficient, rolling friction coefficient and cohesion have the most significant influence on an AoR. The optimisation model determines ideal parameters for simulating AoR that match experimental values. When applied to single-wheel simulations, there is a slight reduction in traction coefficient for cohesive soil. Differences in sinkage, wheel trace and soil motion are negligible. \ \&#xNAN;*Conclusions.* Alongside the parameter calibration performed, the results of the simulations are considered suitable for traction performance. Improvements can be made with soil depth and consideration of void ratio. For a homogenous soil, cohesion may not be critical to the soil response. Future studies will use direct comparison to experiment, reduced gravity experiments and lunar simulant results to refine the simulations. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 0709 / Proposal of swarm rovers’ collaborative locomotion with expansion and contraction... Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Proposal of swarm rovers’ collaborative locomotion with expansion and contraction mechanism for driving a loose slope Authors: Kanta Fujimura, Daisuke Fujiwara, and Kojiro Iizuka Abstract: NASA, China and the Soviet Union have done a mission to the Moon since the 20th century. Large-sized rovers have been used for the explanation of the Moon’s surface. However, some organizations, such as JAXA and NASA, plan to explore the Moon with a lot of small-sized rovers called swarm rovers. Swarm rovers will make the explanation more efficient. A simple two-wheel rover is planned for lunar swarm rovers, but a wheel-typed vehicle has a risk of a slip due to loose ground on the Moon. To solve this problem, we propose collaborative locomotion of two-wheel swarm rovers for traversing loose slope. In this locomotion, multiple rovers connect with each other. When one rover moves, the other rovers stop, and their wheels are fixed relative to the ground. Thus, the locomotion uses the traction of static wheels (non-rolling wheels). To confirm the effect of the proposed locomotion, this paper developed testbed rovers. The rover has magnets and a linear actuator; therefore, they can connect each other and perform locomotion like an inchworm. Furthermore, the authors implemented experiments of driving loose slope with 6 testbed rovers to evaluate the locomotion’s performance. The results suggested that the proposed locomotion could traverse higher loose slope than the normal traveling. Also, the amount of slip suppression increased as the number of connected rovers multiplied. However, once the number of rovers exceeded a certain number, the amount of slip suppression did not increase even if the number of rovers multiplied. In summary, this paper argues that swarm rovers can suppress a slip on loose slope via collaborative locomotion using a drawbar pull force of static wheels. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 0889 / Skidding suppression method using “discrete 4-wheel-drive typed rover” considering... Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Skidding suppression method using “discrete 4-wheel-drive typed rover” considering steering angle at traveling across loose slope Authors: Kojiro Iizuka, Tatsuhiko Suga, Takaaki Sakata, and Daisuke Fujiwara Abstract: Wheeled rovers, which are capable of wide-area and detailed exploration, are widely used for lunar and planetary exploration to expand human activity areas. The Moon and planets have many steep slopes such as craters, and their surfaces are loose soil ground with accumulated particles called regolith. When a rover traverses such loose soil slopes, there is a risk that the rover may deviate from the target path because of it is getting to skid to the downward direction of the slope. Therefore, it is necessary to suppress or decrease the skidding. A discrete 4-wheel-drive typed rover has been focused on to solve this problem in this study. Discrete 4-wheel-drive typed rover can be moved by a unit of a chassis and a wheel independently like a legged rover. This proposed method was more effective in suppressing skidding than the conventional wheel-driven method, but skidding was observed during wheel motion due to the lack of force on the upper side of the slope. This study is focused on “the steering angle”, which can generate the force on the upper side of the slope, to further suppress skidding. Experiments were conducted to measure the amount of skidding across an 800 mm slope using the test bed. The results showed that the amount of skidding is decreased as the steering angle is increased. Moreover, the steering angle to the upper side of the slope is effective in suppressing skidding. Thus, in addition, a discrete driving method, to add “the steering angle” has indicated effective suppression of skidding because of a steered wheel generates forces on the upper side of the slope. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 1098 / Simulation of change in supporting force when imparting vibration by distinct element method Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Simulation of change in supporting force when imparting vibration by distinct element method Authors: Tomohiro Watanabe, Ryoma Higashiyama, Kojiro Iizuka, and Dai Watanabe Abstract: Robots with leg mechanisms have been investigated for planetary exploration as exploration rovers with outstanding running performance. The legged rovers are efficient in moving on rough terrain because the leg mechanism has a high degree of freedom. However, the surfaces of planets (For example, Mars and the Moon etc.) are not only rough but also loose. Owing to the inherent characteristics of loose ground, legged rovers mostly slip because the motion of their legs deforms the surface of loose ground. To solve this problem, we proposed a walking method for preventing legged rovers from slipping. Our previous study confirmed that the shear strength of the ground and sinkage of the rover legs increased when imparting vibration. In-creasing these parameters cause an increase in the supporting force, which is the resistance force exerted on the legs of the rovers by the ground. The running performance of a legged rover is related to the supporting force. The walking method was proposed based on the effects that vibration changes the ground parameters. The proposed method's ef-fectiveness was shown by an experiment in which a legged testbed walked on loose ground. To improve the running performance of legged rover, the supporting force must be estimated to select a suitable vibra-tion that can efficiently increase the bearing capacity. In this study, we simulated the bearing capacity when imparting vibration to the ground by the discrete element method (DEM). The simulated result was similar to the actual change in the bearing capacity when imparting vibration qualitatively. This relationship offers valuable information for under-standing the mechanism whereby the bearing capacity is increased by imparting vibrations. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 1453 / Suppressing the reduction of the traveling displacement on loose soil for rovers with... Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Suppressing the reduction of the traveling displacement on loose soil for rovers with the function of a wheel walking Authors: Daisuke Fujiwara, Qingze He, and Kojiro Iizuka Abstract: The rovers with cylindrical wheels have a risk of failing to move in the loose soil area, such as the surface of the lunar/planet. The movement using the supporting force of the locked wheel, for example, a wheeled walking, or push-pull locomotion, can reduce the risk. In the locomotion, the rover fixes a wheel to the ground and pushes or pulls the other wheel. Many studies have developed these kinds of rovers, for example, Scarab, Marsokhod, and ExoTeR. Furthermore, our previous studies confirmed that the increase in the supporting force by the increase in sinkage of the locked wheel suppresses the reducing the traveling distance. However, the problem is that increasing the traction load still reduces the amount of traveling distance, especially in loose soil with a slope. To address the problem, this paper focuses on the locomotion sequence of the wheel rotation during the pushing or pulling of the other wheel. Then, this paper proposes a method to change the amount of wheel slip during the push and pulling sequence. To confirm the effect, this paper performs a traveling experiment on loose soil using a small testbed rover. The travel-ing methods are push-pull locomotion, push-pull locomotion with large sinkage, and rotational wheel traveling. The slope angles are 15, 20, 25, 30, and 32. The wheel is a lugs wheel. The experimental results indicated that the method using the large slip during the push or pull scheme suppressed the reduction of the displacement. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 1522 / Tractive performance of rigid wheel in granular media using coarse-scale DEM models Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Tractive performance of rigid wheel in granular media using coarse-scale DEM models Authors: Bohumir Jelinek, Angela Card, George Mason, Thomas James, Karl Grebner, Thomas Skorupa, and Jody Priddy Abstract: Understanding the interaction between wheel and granular media in variable loading conditions is critical for prediction of net traction of wheeled and tracked vehicles in off-road environments. The discrete element method (DEM) is routinely used for modeling vehicle performance, but although simulations seem realistic, the method's accuracy is often not fully established. In this work, the DEM modeling accuracy is assessed by the comparison of ten DEM soil models with laboratory soil-bin measurements of the net traction, gross traction, and sinkage of a wheel operating in sand. Laboratory soil-bin measurements, serving as a reference for DEM simulations, were taken from physical experiments by Shinone et al. \[2010], examining a 165/60R13 wheel with constant circumferential velocity of 97.6 mm/s and vertical contact load of 980 N operating in powered conditions under slips in the range of -5.9% to 54.8%. The set of ten DEM models for soil particles and particle-box interaction was a subset of the Generic Material Model (GEMM) database from Altair®'s EDEMTM software package, choosing the best match to the particle size, bulk density, and angle for repose for dry sand. Parameters for wheel-particle interaction were taken from the GEMM database and from the tire-soil parameter set used by Hu et al. \[2021]. Given large particle size and no additional calibration of the DEM model, a good qualitative agreement for the gross tractive effort and sinkage is encouraging. The largest discrepancy is observed for the net tractive effort at large slip. A need for smaller particle size and further calibration are suggested for a future effort. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 1638 / Analysis of tire characteristics on road surface with volcanic ash fall Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Analysis of tire characteristics on road surface with volcanic ash fall Authors: Junya Yamakawa and Ryosuke Eto Abstract: Mt. Fuji in Japan has erupted repeatedly in the past in cycles of about 100 years. Although there are currently no signs of eruption, it is undeniable that an eruption will occur in the near future. An eruption could produce 2-10 cm of ash fall in the Tokyo metropolitan area, which is about 100 km away from Mt. Fuji. An event was held in which asphalt paved parking lots were covered with volcanic ash to allow citizens to experience how driving vehicles would be affected by the ash fall caused by the volcanic eruption.We collected data by driving an instrumented vehicle on the volcanic ash roads at this event site. In this presentation, we describe the results obtained by analyzing the data collected on the simulated ash roads. It is relatively easy to see the characteristics of longitudinal tire force, i.e., rolling resistance, driving force, or braking force, because, like friction force, they can be expressed as dimensionless quantities divided by the vertical load. However, the tire side force generated during vehicle turning is largely due to the sideslip angle, but it is also affected by the camber angle, which is the inclination of the tire from the vertical plane, as well as the vertical load. Since the side force data during driving is collected while the values of not only the lateral slip angle but also the ground load and camber angle are changing, it is necessary to determine the relationship between these variables and the side force. For this reason, we analyzed the side force data using a Gaussian process, which allows regression on multiple variables. For Gaussian process regression, since it takes time to find appropriate values for the hyper-parameters of the kernel, we also attempted to model the process using a neural network. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 1805 / Accelerating graph networks for real-time physics simulations Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Accelerating graph networks for real-time physics simulations Authors: Mohammad Jasim Usmani and Krzysztof Skonieczny Abstract: Physics-based simulations are crucial for analyzing interactions between physical objects and are very commonly used in areas such as terramechanics. The discrete element method is an accurate way to model the interactions between the soil particles, however, it is very computationally intensive. One promising alternative is to use Graph Network architecture which uses graph neural networks to learn and approximate the dynamics of the physical system fed into it. Even though this is faster, due to the high dimensionality of the dataset, the inference is performed on a very large graph and rollouts are not in real-time. To accelerate the simulation, one way developed recently in our laboratory is to use dimensionality reduction techniques such as principal components analysis to identify the modes in the dataset that carry the highest variance. These modes are then fed into the Graph Network along with the rigid body to train the model. Although the reduced-order dataset results in a much smaller graph than the original dataset, the graph fed into the network is still naively fully connected. This research aims to further accelerate this subspace framework by identifying a partial graph for the network without compromising either the performance or training. This identification of the partial modes is done by Neural Relational Inference (NRI). The NRI model is based on a variational autoencoder where the encoder can extract a partial graph that can still perform inference on the GNS without loss in accuracy. We demonstrate the effectiveness of our approach on blade cutting as well as wheel simulation datasets and show that this framework has reduced the inference time from 0.35 seconds per second of simulation to 0.17 seconds, an approximately 2x speed up. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 2145 / Obstacle performance and wheel failure test analysis of Zhurong rover Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Obstacle performance and wheel failure test analysis of Zhurong rover Authors: Hongtao Cao, Meng Zou, and Jianqiao Li Abstract: A large number of rocks are distributed on the surface of Mars, and the wheels have potential risks such as puncture and fracture, which pose a threat to the trafficability of the Mars rover. Therefore, it is of great significance to carry out the experimental analysis of the obstacle performance and failure mechanism of the Zhurong Rover wheel. A ground test model of the Zhurong Rover was used as the ground simulation vehicle, and the stone height and driving speed are taken as variables. The wheel drive mechanism power, current and wheel obstacle resistance are taken as the test indexes, and the obstacle performance test of the Mars rover is carried out. The test results show that the variation trend of average power and current is obvious, and there will be obvious slope peak when crossing the obstacle, which can judge when the Mars rover crosses the obstacle and the state of crossing the obstacle. When the wheel crosses the obstacle, the vehicle power, current and wheel resistance are positively correlated with the obstacle height and driving speed. In order to verify the strength and damage resistance of the wheel, the extreme driving conditions were set to test the failure modes such as wheel damage, puncture and fracture. The Zhurong Rover wheel was shown to have excellent damage resistance. The analysis results verify the obstacle surmounting performance of the Mars rover and the strength and damage resiliency of the wheels. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 2177 / Effects of road wheel load, driving speed and track slip upon stress state in sandy... Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Effects of road wheel load, driving speed and track slip upon stress state in sandy soil under tracked vehicle loading Authors: Michał Kuszneruk, Paweł Tomiło, Jarosław Pytka, Dawid Tatarynow, and Rafał Longwic Abstract: This study analyses experimental data of stress state under loads of running tracked vehicles in sandy soil measured with the SST (Stress State Transducer) in field experiments. Based on measured soil pressures, soil stresses in the orthogonal and octahedral planes were determined at the depth of 20 cm beneath the test vehicles’ right track. Three different tracked vehicles of masses—44.3, 12.13, and 9.7 Mg—were used in the experiment. Effects of road wheel loads distribution, driving velocity, and track slip on soil stress state were determined and analyzed. The field experiment were compared with analytical predictions based on Boussinesq theory as well as the Mean Maximum Pressure (MMP) and Nominal Ground Pressure (NGP) models. A model of an artificial neural network was developed, which allowed the detection of the moment when the road wheel of the tracked vehicle is above the stress state transducer (SST) sensor. It was concluded that the vehicle maneuver or drive mode (rolling, driving, velocity) affected soil stress state significantly. This is because of a varying wheel load vector during different drive modes. Finally, use of a flat value of wheel load in modelling and simulations of soil stress distribution may lead to erroneous results, without taking into account the wheel mode effect. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 2437 / Improving predictive control methods on off-road vehicles with realistic steering preview\... Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Improving predictive control methods on off-road vehicles with realistic steering preview inputs Authors: Andries Peenze and Schalk Els Abstract: This paper investigates improvements to predictive control methods for off-road vehicles with the addition of realistic steering preview. The objective of this study is to improve the performance and efficacy of predictive controllers by accounting for significant time delays in active and semi-active systems on vehicles. The zero-order and first-order hold methods for steer preview are compared to a more realistic steer preview obtained from the curvature of the path, vehicle velocity, and tyre lateral force properties. A new semi-active suspension system, rear wheel steering, and individual brake control are used as the actuators on this off-road vehicle. The results show that the addition of a realistic steering preview improves the handling performance of the vehicle in a severe manoeuvre without affecting normal driving on smooth and rough roads. The controller can pre-empt and consider the effect of the actuator time delays, and the preview states from the predictive controller are more representative over the prediction horizon. In conclusion, the findings suggest that the addition of a realistic steering preview improves the performance of a predictive controller on vehicles, and further investigation of other disturbances and their preview effects on the system should be conducted to find further improvements for predictive control strategies on vehicles. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 2765 / Obstacle detection vision system enabling autonomous mounding on clearcuts Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Obstacle detection vision system enabling autonomous mounding on clearcuts Authors: Songyu Li, Håkan Lideskog, Magnus Karlberg, and Ruben van Westendorp Abstract: After final felling, a clearcut needs to be prepared as soon as possible for subsequent planting with the purpose of restoring forest reserves. In Sweden, the multi-row continuously advancing mounder is a mature and widely used solution for site preparation. It is driven by a base machine, where rotating mattock wheels make upside-down mounds on the area to prepare for subsequent planting. During operation, a plurality of obstacles such as stumps, residual trunks, single trees, large stones, and the like, remain after felling and are scattered at the site, forcing the operator to continuously watch out for them. These obstacles can to some extent be avoided through control of each mattock wheel arm, which causes inconvenience to the operator and reduces the efficiency of the mounding procedure. Thus, by adding automatic obstacle avoidance functionality to the mounder, the efficiency and working environment can be significantly improved. In this paper, we present a feasible solution for real-time detection of obstacles in front of the mattock wheels of a mounder using a realistic simulated forest environment combined with a vision-based deep learning detection algorithm. The developed system can effectively identify most target obstacles and provide a reference for the operation of the mounder, either manually or by machine control. The successful implementation of this system also provides a starting point to further improve the automation level of mechanized site preparation, while further improving the mounders’ working efficiency. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 2801 / In Situ Soil Property Estimation for Autonomous Earthmoving Using Physics- Infused Neural... Paper presented at the 16th European-African Regional Conference of the ISTVS Title: In Situ Soil Property Estimation for Autonomous Earthmoving Using Physics- Infused Neural Networks Authors: W. Jacob Wagner, Ahmet Soylemezoglu, Dustin Nottage and Katherine Driggs-Campbell Abstract: A novel, learning-based method for in situ estimation of soil properties using a physics-infused neural network (PINN) is presented. The network is trained to produce estimates of soil cohesion, angle of internal friction, soil-tool friction, soil failure angle, and residual depth of cut which are then passed through an earthmoving model based on the fundamental equation of earthmoving (FEE) to produce an estimated force. The network ingests a short history of kinematic observations along with past control commands and predicts interaction forces accurately with average error of less than 2kN, 13% of the measured force. To validate the approach, an earthmoving simulation of a bladed vehicle is developed using Vortex Studio, enabling comparison of the estimated parameters to pseudo-ground-truth values which is challenging in real-world experiments. The proposed approach is shown to enable accurate estimation of interaction forces and produces meaningful parameter estimates even when the model and the environmental physics deviate substantially. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 2936 / Moisture content impacts on soil load bearing capacity and its spectral behaviour Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Moisture content impacts on soil load bearing capacity and its spectral behaviour Authors: Ahmed Elawad Eltayeb Ahmed, Gyorgy Pillinger, and Peter Kiss Abstract: Soil moisture content plays a crucial role in determining the load-bearing capacity of soil, which is an important mechanical property in off-road engineering since it shows the soil's ability to withstand a load without excessive deformation or failure. The term soil spectral behaviour refers to how soil interacts with light of different wavelengths, either by absorbing or reflecting it. One of the factors that can affect the soil’s spectral behaviour is its moisture content. From an autonomous vehicle’s aspect, understanding the impact of soil moisture content on its spectral reflectance and bearing capacity is a critical consideration. This study investigates the influence of soil moisture content on the soil load-bearing capacity (pressure-sinkage relationship) and its spectral behaviour. The Bevameter technique was utilized to determine the soil-bearing capacity, using the moisture analyzer for quantifying the soil moisture content. In addition, a spectrophotometer was employed to analyze the soil colour (spectral behaviour). The results show that the soil moisture content has a significant effect on both the load-bearing capacity and the spectral reflectance of the tested soil. The findings have significant implications for off-road vehicles since the load-bearing capacity of the soil is a critical factor affecting the vehicle’s performance over soil terrain. Understanding the effect of moisture content on the load-bearing capacity and the spectral behaviour of soil can help in optimizing a vehicle’s design and its operation on various soil types under different moisture conditions. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 3280 / Comparison of tweels and pneumatic tires on LTATV military vehicle Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Comparison of tweels and pneumatic tires on LTATV military vehicle Authors: Michael Parker, Clifford Witte, and Allan Wheeler Abstract: Tire technology and design can have a significant impact on a vehicle’s performance across different surfaces, seasons, and operating environments. Two examples of this are winter tires and airless tires. Winter tires are typically used in the United States in areas where snow and ice are present for a significant portion of the year like in the northern states and Alaska. Similarly, airless tires have recently started to immerge as viable options for skid steers and light utility vehicles like side-by-side vehicles. The military operates in cold regions and austere regions where off-road mobility is paramount and winter tire and airless tire technology could provide a tactical advantage. Airless tires are less susceptible to puncture from difficult terrain conditions, shrap metal, bullets and could be a viable option to run flat tire designs. This research focuses on the performance of a LTATV military vehicle on snow and ice with the standard issue mud and snow nematic tires as compared to studded and standard airless tires. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 3493 / Numerical modeling of a tire on undrained saturated clay using FEM, ALE, and SPH Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Numerical modeling of a tire on undrained saturated clay using FEM, ALE, and SPH Authors: Varsha S Swamy, Rashna Pandit, Alba Yerro, Corina Sandu, Denise M. Rizzo, Katherine Sebeck, and David Gorsich Abstract: Modeling and performance prediction of tires on wet, plastic, cohesive soils is a challenge. Unlike dry soils, in wet soils the undrained shear strength is lesser. The worst scenario is when the soil is fully saturated. This work aims at modeling highly deformable saturated clay and predicting the performance of pneumatic tires on such terrain. The short-term effect on the soil due to single tire pass is of focus. First, the modeling and validation of the soil material model is discussed. Dealing with saturated soils, it is important to understand the effect of the water in the pores. The total stresses acting on the soil can be divided into the stress on the soil skeleton (effective stresses) and water (pore water pressure). It is the effective stresses that determine the soil failure. Hence, material models are calibrated and validated from geotechnical experiments using two different frameworks: (a) total stress (b) effective stress. In the total stress analysis, commonly found in the literature, soil and water are modeled as one medium. In the effective stress analysis, the model represents only the soil skeleton and it is hydro-mechanically coupled to produce a larger range of initial stress states. The performance of the tire using different numerical techniques including FEM, Arbitrary Lagrangian Eulerian (ALE), and Smoothed Particle Hydrodynamics (SPH) are compared using these models. Finally, it is concluded that with the effective stress model, there is accumulation of excessive pore water pressure, which may affect the second pass later. In addition, the FEM model fails to give acceptable solutions for higher normal loads and slip ratios as a result of excessive deformation. ALE and SPH give more stable solutions when large deformations develop. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 3507 / Determination of the tractive forces of a tractor based on the reconstruction of... Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Determination of the tractive forces of a tractor based on the reconstruction of tire – soil contact surface obtained by means of photogrammetry Authors: Jaroslaw Pytka, Tomasz Śliczniak, Leszek Gardyński, Aleksander Czajka, and Sławomir Tarkowski Abstract: The aim of the work was to develop a method for determining tractive forces based on a three-dimensional reconstruction of the tire - soil contact surface. The photogrammetry method was used to reconstruct the contact surface between the tractor tire and the soil, further the traction forces were determined using the Bekker model. The value of the contact pressure was determined on the basis of the three-dimensional model of the contact surface. The tow test method was used to measure traction forces as part of verification tests. Field measurements were carried out for different wheel load values, on two soils, sandy and loamy, at different moisture. It was found that the obtained values of the drawbar pull force, determined analytically using photogrammetry, show small discrepancies in relation to the values measured in field tests using a dynamometer. In the case of loamy soil, it was noticed that with increasing moisture, the sinkage of the wheel (rut depth) as well as the horizontal displacement of the soil was smaller. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 3796 / The issue of assessing the suitability of own simulation models for testing off-road vehicles Paper presented at the 16th European-African Regional Conference of the ISTVS Title: The issue of assessing the suitability of own simulation models for testing off-road vehicles Authors: Przemysław Simiński, Krzysztof Kosiuczenko, Marek Nowakowski, and Alexander Kravcov Abstract: Assessing the suitability of simulation models for testing off-road vehicles is an important aspect of ensuring that the models accurately represent real-world conditions and can be used effectively to inform vehicle design and development. Here are some key considerations to keep in mind when assessing the suitability of your own simulation models for testing off-road vehicles: The first consideration when assessing the suitability of a simulation model is its accuracy. The complexity of the model should be appropriate for the intended use case. The simulation model should be able to take input data that is readily available, such as terrain maps, weather data, and vehicle specifications. This will help ensure that the model can be easily used by designers and engineers in the development process.Finally, it is important to verify and validate the simulation model to ensure that it is reliable and can be used with confidence. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 3797 / Disturbed and naturally recovered soil surface as a ground for subsequent vehicle mobility... Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Disturbed and naturally recovered soil surface as a ground for subsequent vehicle mobility operations Authors: Kersti Vennik Abstract: The passages for off-road military vehicles will leave behind disturbed soil conditions because vehicles compact and displace the layers of soil. One of the first visual signs of disturbance are ruts. Thus, former active combat areas can have a serious effect on subsequent operations and the mobility of vehicles. More precisely, an uneven soil surface will remarkably increase the vibration of travelling vehicles and over-compacted soil layers affect soil water dynamics that, in turn, have a long-lasting effect on soil strength. Previous studies have revealed that disturbed conditions can affect the physical parameters of soil for decades. Nevertheless, soil can naturally recover from being disturbed thanks to freezing-thawing cycles, wetting-drying cycles, and biological activity. However, the rate of recovery depends on the physical parameters of soil. The objective of this study was to monitor and summarize the natural recovery rate of soils with different texture and organic material content. As an experiment, we carried out a single pass and repeated passes with a military truck (total weight of 70 kN). The ruts that formed were monitored and soil samples were collected up to 2.5 years after wheeling. Measurements in the field included rut depth determination, penetrometer and bulk density as well as field-saturated hydraulic conductivity measurements. The results about the rate and severity of natural recovery on different soils are presented and discussed herein, including the overall conclusions about mobility conditions for follow-on military operations. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 3835 / Effect of steer angle rate upon tyre lateral force generation on two different soils Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Effect of steer angle rate upon tyre lateral force generation on two different soils Authors: Dawid Tatarynow, Michał Kuszneruk, Piotr Budzyński, Jarosław Pytka, and Paweł Tomiło Abstract: The mechanism of formation and the characteristics of the tyre lateral force play an important role in terms of driving dynamics, safety and comfort. In the case of an off-road vehicle, the generation of tyre lateral force is, among others, dependent on the soil. The effects of the three-phase nature of the soil medium may cause the characteristics of the lateral force build-up to be degressive or progressive. Experimental research was undertaken to determine tyre lateral force on the steered wheel of the Suzuki Vitara off-road vehicle driven on loess and sandy soil as well as on wet snow. The vehicle was equipped with rotating wheel dynamometers and a steering robot. The measurement of the lateral force was carried out for three values of the steer angle rate, δ: 100, 500 and 1500 deg/sec. Based on the obtained results, FY(δ) characteristics were obtained and further analyzed in order to determine the mathematical function describing the investigated mechanism of tyre – soil interaction. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 4141 / Modeling and verification of a full-scale forestry vehicle real-time multi-physics digital tw Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Modeling and verification of a full-scale forestry vehicle real-time multi-physics digital twin Authors: Mattias Lehto, Antti Tikanmäki, Torbjörn Lindbäck, Håkan Lideskog, and Magnus Karlberg Abstract: At Luleå University of Technology, an offroad vehicle capable of performing autonomous forwarding of full-scale logs, has been developed and built. This vehicle serves as a modular research platform, where different hardware, software, and algorithms can be exchanged, tested, and validated. To further facilitate this research, a real-time multi-physics digital twin of the vehicle has been developed. The digital twin can be executed either in fully virtual or in Hardware-in-the-Loop mode. Virtual and hybrid testing and development are expected to increase the efficiency, safety, and sustainability of these activities. Future envisioned use-cases also include machine learning and generation of auto-annotated detector training data. The digital twin features multibody simulation, hydraulics, contacts and collisions, flexible tires, emulated sensors, and co-simulation capabilities. The test environment is a physical environment that has been recreated digitally, using data from a UAV-mounted camera and lidar, as well as handheld RTK GPS measurements. Therefore, accurate GPS positions can be obtained from the digital environment. The digital twin is equipped with an emulated GPS sensor and can thus follow the same GPS tracks as the physical vehicle. This paper presents the development and verification of the digital twin model. Calibration and testing of the digital twin’s hydraulically actuated articulated joint is detailed, and the results are analyzed. The modeled hydraulics of the articulated joint show realistic dynamics. It is also shown that the level of detail of the wheel motors’ hydraulic circuits, affects the calibration of the hydraulics model of the articulated joint, as they affect the resistance during turning. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 4456 / Modeling soil-tool interaction of a cultivator sweep using DEM Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Modeling soil-tool interaction of a cultivator sweep using DEM Authors: Peeyush Soni, Sumit Parmar and Prakhar Patidar Abstract: The discrete element method (DEM) is a powerful tool for predicting soil disturbance and cutting forces in soil cutting tools, aiding in design optimization. In this study, we calibrated DEM input parameters to model a sandy loam soil using the hysteretic spring contact model, linear cohesion model, and a nominal particle radius of 5 mm. The DEM simulations were validated using experimental lab results, considering the effects of speed and depth. Some soil properties were measured in the laboratory, while others were obtained from literature and used as input parameters in Altair EDEM. We constructed a 3-D model of the cultivator tyne, and by combining the implement design with soil parameters and implement parameters (depth of operation, various speeds), we performed simulations in Altair EDEM software. Prior to the soil bin test, essential sensors such as load cells and torque transducers were calibrated. Overall, the DEM results closely aligned with the experimental findings, demonstrating similar trends. Comparing the measured and predicted tillage forces under various conditions, we achieved correlation coefficients ranging from 0.8 to 0.85. This demonstrates a highly accurate prediction of tillage forces. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 4595 / Evaluation and comparison of driving performance of a lunar exploration rover wheel in... Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Evaluation and comparison of driving performance of a lunar exploration rover wheel in different soils Authors: Keisuke Takehana, Shino Kizaki, Kentaro Uno, Tomomi Tanaka, Gentaro Suda, and Kazuya Yoshida Abstract: Wheeled mobile robots, rovers, are highly effective in lunar exploration as they can move the Moon's surface for detailed exploration. However, the lunar regolith, soft soil with fine powdery sand, can cause wheel slippage, resulting in an inability to travel for the rover. To analyze the driving performance of a rover wheel, a single-wheel testbed is usually used. In our experiment, force sensors mounted on the wheel measure the reaction force, which allows computing the wheel's traction performance evaluation criteria based on the Terramechanics theory. This system can control the rotation and translation of the wheels separately, realizing experiments in any slippage condition. This method can measure accurate traction data under more precise slip ratios than the conventional single-wheel tests, where a traction load is applied along with wheel rotation. Moreover, this testbed can conduct experiments using regolith simulant with a cohesive property that has similar mechanical properties to those of lunar regolith, in addition to Toyoura sand, which is non-cohesive sand collected from the earth. This paper presents the results of a driving test on two types of loose soil: Toyoura sand and regolith simulant (FJS-1). The wheel used in the experiment is the preliminary version of the actual flight model of a 5 kg class lunar exploration microrover. The results reveal that the traction performance on both sands improves as the slip ratio increases. The performance did not depend on velocity but on vertical load. It should be noted that the cohesive simulant shows a higher difference in traction performance than Toyoura sand. These findings, measured in detail from the low-slip to the high-slip range, contribute to the actual driving operation of the rover missions. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 4681 / Simplified models of terrain-vehicle interaction for real-time applications Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Simplified models of terrain-vehicle interaction for real-time applications Authors: Dávid Körmöczi and Péter Kiss Abstract: Accurate modeling or simulation of the vehicle-terrain interaction is critical for effective off-road vehicle navigation. While several high-accuracy methods exist (for example FEM simulation) they typically require computational capacity that exceeds what can be installed in a vehicle. Therefore, they are not applicable for real-time off-road vehicle navigation purposes, where computer hardware capacity is limited by the need for onboard installation. To address this challenge, simplified and less detailed models must be developed for real-time applications. This paper compares three different two-dimensional static terrain-vehicle models, considering accuracy and computational capacity requirements. Results of the comparison provide insights into the suitability of each model for real-time navigation of off-road vehicles. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 4816 / Effects of humidity on the emissions of the diesel engines Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Effects of humidity on the emissions of the diesel engines Authors: Dániel Szőllősi and Péter Kiss Abstract: Above any common perspective, for HD and off road conditions at least, the usage of the internal combustion engines will continue for decades because of the advantages on this area, like fuel storing, weight and range. During the operation of the internal combustion engines, the main contributors for the burning process is the fuel and air. The fuel component possibilities and effects widely investigated, but almost no attention for the other contributor, the air. It is considered as a fix parameter but at least one component, the humidity can widely change depending on environmental circumstances and can have great effect on the engine operation. It can be considered as the oldest and simplest emission treatment technic what we using – even unnoticedly – since the usage of the internal combustion engine. It is essential to have a proper overview on this area, it should be summarized and clearly understand the effects of air humidity. This knowledge is a baseline for lot of further investigation in this area. The water effect is significantly important for the diesel engine, where excess air going into the combustion chamber. This paper gives us insight into the different levels of humidity induced performance and emission differences. It reveals the connection between the particle number and gas emission in relation to the water introduced to the combustion chamber. To answer today’s most urging questions, in this survey, data also provided connected to the ultrafine particles ( sub 23nm), which emerging with the new emission regulations. The paper provides guidelines and possibilities to show the potential of artificially increased water content in the combustion air and the potential of water-using techniques. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 5552 / Vehicle drawbar test method with improved measurement and control Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Vehicle drawbar test method with improved measurement and control Authors: Orian Welling, Zach Tomberg, and Mike Stearns Abstract: In this work, we show a new vehicle drawbar test method that allows simple regulation of a constant vehicle speed through the test while requiring relatively little training or practice from the test vehicle driver. The improved method relies on a capstan winch mounted on a fixed stable point with a controlled release of cable over a 600 foot distance. The winch and cable are capable of sustaining loads up to 20,000lbs at a constant cable speed. The load on the cable is measured with a vehicle mounted load cell. In the paper / presentation, we show a comparison of test data from drawbar tests utilizing a separate holdback vehicle and holdback driver with tests using the new methodology and show that measurement stability is improved and that the target vehicle speed is held much closer to the target point, eliminating error or need to correct for vehicle acceleration. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 6027 / Digital precision planning tool for autonomous forest regeneration of mixed tree species Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Digital precision planning tool for autonomous forest regeneration of mixed tree species Authors: Erik Arvidsson, Magnus Karlberg, Karin Hjelm, and Håkan Lideskog Abstract: Forest management planning often neglects within-site variation, focusing on decisions for entire forest stands, which impedes effective forest regeneration. Incorporating mixed species stands can mitigate risks associated with monocultures and offer numerous benefits. However, implementing mixed stands present challenges such as higher costs and complex management. This research aims to develop a method for precise and efficient forest regeneration planning in Swedish silviculture. The study developed digital tools to be used in forest regeneration planning and makes it suitable for deployment on autonomous vehicles. Traditional regeneration methods involving labour-intensive processes and soil disturbance have limitations, while autonomous vehicles show promise in improving energy efficiency and reducing soil damage. The aim is to increase site productivity by determining the spatial distribution of varied species in mixed stands using density constraints set by the user. The Digital Precision Planning Tool (DiPPT) developed in this study utilises existing site index maps to enhance biomass growth and select the most suitable species for each location. The tool considers species-specific site productivity and density constraints to create the planting map. Two approaches were developed: the Max function, which selects the species with the highest site productivity for each location, and an iterative process that optimises species-specific factors to meet user-defined density constraints. The DiPPT was validated using test sites provided by the forest company Sveaskog. Results show that the tool’s approach outperforms manual planning in terms of site productivity. The average site productivity using DiPPT is 10% higher compared to manual planning. The tool demonstrates its potential for optimising species placement and promoting species diversification in forests. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 6630 / Real-time measurement of tire sinkage using stereo cameras Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Real-time measurement of tire sinkage using stereo cameras Authors: Hannah White, Corina Sandu, Jyotirmoy Mukherjee, Andrea L'Afflitto, David Gorsich, and Michael Cole Abstract: There is a need for autonomous vehicles operating off-road, such as in military operations and farming. However, most established models, planning, and control algorithms for autonomous vehicles are created assuming on-road conditions only and, hence, underperform when employed otherwise. An approach to overcome this limitation is to feed these algorithms with real-time data on the terrain parameters and the terrain-vehicle interaction parameters. One of the key parameters to estimate for reliable off-road operations is is tire sinkage. This parameter affects the slip-sinkage relationship, which, in turn, has a significant influence on the tractive performance of the vehicle. This paper presents a method for real-time sensing and estimation of the sinkage of off-road vehicles under the assumption that the rut left behind has the same value as the sinkage; this assumption is driven by the need for low computational times and is proven experimentally to be sufficiently accurate in problems of practical interest. Specifically, we are using image processing techniques to assess the sinkage of a tire on a deformable surface. To this goal, we collect the depth data of a tire rut in real-time using two stereo cameras. The first camera measures the profile of the undisturbed terrain in front of the tire. The second camera measures the depth profile of the tire rut depth. These profiles are compared to estimate the final rut depth. The measurements from the two cameras are also used to compute the tire’s entry and exit angles; these parameters can further be employed in the computation of the shear stresses along the contact patch of the tire. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 6690 / Comparative evaluation of methods to evaluate penetration resistance for Clegg hammer and... Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Comparative evaluation of methods to evaluate penetration resistance for clegg hammer and cone penetrometer Authors: Mohit Nitin Shenvi, Corina Sandu, and Costin Untaroiu Abstract: The computation of the sinkage and penetration resistance in deformable terrains is an important aspect for the evaluation of the terrain properties from a terramechanics perspective. The Clegg Impact Hammer and the Cone Penetrometer are two widely used devices for evaluating the penetration resistance of soils, primarily. Variants of the cone penetrometer technique that have been used for snow evaluation are the Rammsonde and the Russian Snow Penetrometer, and very few studies exist for using the Clegg Impact Hammer technique for snow. For terrain such as higher compaction snow, like the one used in ASTM F1805 traction testing of tires, the process of measuring the terrain resistance becomes very complex. In this work, the Clegg Impact Hammer and an in-house developed device inspired by the Russian Snow Penetrometer are employed to measure the properties of compacted snow. This work focuses on the relative evaluation of the sinkage and penetration resistance parameters based on the classical methods widely used in literature and two new proposed hypotheses for the evaluation of the outputs of these two devices respectively. The results of the comparison provide insight into the amount of variation that is possible in the calculation of these two parameters. Analysis of the results from a physics-based perspective will be discussed. Future work in this field would be an evaluation of sinkage and penetration resistance of several different terrain types to validate the proposed hypothesis and/or provide correction factors to the hypothesis based on the field testing results in different terrains. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 6736 / Ride comfort comparison between 4-poster and straight line driving simulations Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Ride comfort comparison between 4-poster and straight line driving simulations Authors: Cor-Jacques Kat and Schalk Els Abstract: Difference thresholds of whole-body vibration is important to determine perceptibility of changes in a vehicle’s dynamics. Difference thresholds can be used to guide ride comfort improvements. Difference thresholds have been estimated for vertical and multi-axial seat vibration in laboratory settings. It is postulated that estimated difference thresholds in a laboratory setting should be applicable to real world driving conditions given that the stimuli (vibration, noise, visuals, cognitive load, etc.) are similar. This paper considers the stimulus associated with the vehicle’s dynamic response i.e. vibration. The vibration stimulus characteristic of a vehicle on a 4-poster test rig and straight line driving is investigated through simulation. A validated non-linear SUV vehicle model is simulated on a 4-poster test rig and driven in a straight line over road profiles that range from on- to off-road conditions. Each corner of the 4-poster is driven by the vertical road profile associated with that corner. The resulting translational and rotational vibration for all three axes at the driver position make up the vibration stimulus. Based on the level of agreement of the vibration stimulus between the 4-poster and straight line driving, some indication of the applicability of difference thresholds estimated on a 4-poster can be obtained. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 6861 / Research on airplane performance on a grass airfield Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Researches on airplane performance on a grass airfield Authors: Jaroslaw Pytka, Paweł Tomiło, Anna Zalewska-Tytłak, Mateusz Klepka, and Sławomir Tarkowski Abstract: The paper presents experimental researches on airfield performance of an aircraft operating from a grass runway. For this research, a methodology of field measurements was developed and measurements of take-off and landing distance were carried out on a grass airfield, taking into account important factors, such as soil cone index, soil moisture, vegetation density and atmospheric factors. The method of measuring the distance of take-off and landing ground roll based on neural network models turned out to be very convenient to use, the advantage is cheap hardware and ease of use. On the basis of the results of *CI* and *MC* measurements on two test airfields, it was concluded that the ground performance of aircraft obtained at grass airfields with different soil substrate may differ significantly. Therefore, it is necessary to distinguish grass runways in terms of soil type. Flight test results showed that the impact of green vegetation on the runway is more significant than the impact of soil strength, expressed by means of soil *CI*. The overarching goal is to implement the measurement method and obtained results into the GARFIELD system – an online information system on grass airfield conditions. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 7198 / Analysis of aircraft dynamics while overcoming obstacles on a grass runway Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Analysis of aircraft dynamics while overcoming obstacles on a grass runway Authors: Jerzy Jozwik, Jarosław Pytka, Andrzej Łukaszewicz, Sylwester Korga, and Kamil Żyła Abstract: Flying from grass airfields is associated with the risk of surface unevenesses and their impact on safety and comfort during take-off and landing.This paper presents the measurement method and experimental results of a study investigating the effect of terrain obstacle geometry on the aircraft suspension system dynamics. Three different models of terrain obstacle geometry were tested: rectangular, triangular and semi-circular, each model having the dimensions of 300x150x50mm (length x width x height). Experiments were conducted using the GOM PONTOS measuring system, which made it possible to perform a dynamic analysis of the suspension system of a Cessna 152 airplane passing over the obstacles. Airfield experiments were conducted for three takeoff runs of 1200, 1800 and 2700 millimetres for each terrain obstacle model, respectively. The study investigated dynamic parameters of three crucial structural elements of the aircraft's suspension system: landing gear wheel, strut and its mounting points on the fuselage, for which accelerations and velocities were measured when the aircraft was passing over the obstacles. The paper includes details of the measurement method as well as the results and their analysis. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 7477 / Evaluating the pressure performance of DPF filters using engine bench analysis Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Evaluating the pressure performance of DPF filters using engine bench analysis Authors: Norbert Biro and Péter Kiss Abstract: Passenger and commercial transportation have a substantial impact on hazardous air pollution. The progress of exhaust gas aftertreatment technology is closely aligned with global emission regulations. The upcoming Euro 7 legislation in the European Union is anticipated to be more stringent in many aspects when compared to Euro 6, although its specific requirements are yet to be determined. Consequently, new DPF technology is necessary to comply with the regulation. This study aims to compare the pressure hysteresis of the current and proposed new generation DPF substrates. The objective is to draw conclusions and determine the compliance of the upcoming Euro 7 legislation in terms of pressure hysteresis. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 7523 / Assessing performance of light wheeled vehicles on GRC-1 using 3D scanned footprint... Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Assessing performance of light wheeled vehicles on GRC-1 using 3D scanned footprint measurements Authors: Chaitanya Sonalkar, Nikhil Ravichandran, Alexandru Vilsan, Corina Sandu, and Tony Lin Abstract: In off-road conditions, the vehicle mobility is dependent on the terrain and its properties. It is necessary to characterize the soil/terrain in order to assess its traversability and to predict the performance of the tire. If not accounted for properly, it can lead to conditions where the vehicle is stuck due to excessive sinkage or is unable to satisfactorily meet its intended performance. Navigation of wheeled vehicles on fine, dry sands, such as the Lunar Soil Simulant GRC-1, has greater challenges due to very low cohesion properties. This study aims at characterizing the terrain response of such a sandy soil to different loading and slip conditions for light ground vehicles, by studying the 3D shape of the footprint/ rut left by the tire. For this, a white light-based 3D scanner will be used to collect the data. Correlations between the normal load applied, the depth and shape of the contact area, as well as the slip conditions are made to assess their impact on the drawbar pull of the tire. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 7577 / Implementation of moving loads on ice in NRMM Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Implementation of moving loads on ice in NRMM Authors: Susan Frankenstein and Kathleen Jones Abstract: Fording capabilities are common in cross country mobility models. They are limited in capability however due to their dependence on timely water level inputs and are best used for planning purposes based on monthly averages. Few, if any, include water velocity effects when crossing rivers and stream. Less common still are winter crossing considerations. To accurately predict vehicle speed on an ice cover the ice thickness, ice properties, and water depth are required. To solve for the speed an iterative process is needed which is prohibitive in mobility models. In order to implement in NRMM critical speed curves were generated for 37 ice thicknesses ranging from 0.01 – 5 m and 3000 water depths spanning 0.1 – 300 m. Using these curves, two equations, one for the steady state velocity and a second for the critical velocity as functions of water depth and ice thickness were developed. If the water depth is known, the final speed is the minimum of the two otherwise it is set to 6.7 m/s. In NRMM, the minimum ice thickness needed to support a single non-moving vehicle is calculated. Adjustments to the minimum ice thickness can be made for weaker ice. If the ice thickness is greater than the minimum thickness, then the speed and minimum vehicle spacing are calculated. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 8151 / Study on estimation of traveling states using strain information on chassis of lunar and ... Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Study on estimation of traveling states using strain information on chassis of lunar and planetary exploration rovers Authors: Sae Takano and Kojiro Iizuka Abstract: Lunar exploration is underway around the world. The goals of the investigation are sustainable activity on the lunar surface and technological demonstration for Mars exploration. It is an effective method to land and move for investigation on the lunar surface by rovers. However, there is a possibility of a rover skidding due to the loose soil on the lunar surface. This phenomenon causes the rover to deviate from its intended course. Therefore, it is necessary to obtain the driving state in real time. We focus on the strain generated in the rover's chassis. The strain is caused by some kind of mechanical relationship between the rover’s wheels and the ground where it travels. It is therefore expected that the strain has a correlate closely with the driving state. The purpose of this study is to try estimating the driving state of the rover in real time by analyzing the strain value measured with strain gauges mounted on the chassis. The data is accumulated with changing voluntarily the slip ratio of a wheel connected to the chassis. By averaging and FFT analyzing of strain values, a correlate is established between the wheel’s slip ratio and the strain. The slip ratio is estimated from the correlate. The measured data verified that the average value of the strain was larger when the wheel traveled on a loose ground than on a rigid one. It was also verified that the vibration of certain frequencies was smaller when the wheel was running on a loose ground than on a rigid one. This result suggests that the type of surface can be assessed by measuring the strain on the chassis. Therefore, it is believed that the chassis strain and the ground are related. The slip ratio also appears to correlate with the strain. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 8254 / Initial steps towards characterization of a new military cold weather all-terrain vehicle... Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Initial steps towards characterization of a new military cold weather all-terrain vehicle for performance in northern operations Authors: Clifford Witte, Orian Welling, Michael Parker, Michael Stearns, and Zach Tomberg Abstract: The US Army Corps of Engineers - Cold Regions Research & Engineering Laboratory recently acquired two quad articulatedtrack cold weather all-terrain vehicle prototypes to begin characterization of their performance on winter surfaces for force projection, modeling, and simulation. The vehicles were previously used in the Cold Weather All-Terrain Vehicle (CATV) program initiated by the United States Army to select a replacement for the aging Bandvagn 206, designated in the US Army fleet as the Small Unity Support Vehicle (SUSV) and in service for over forty years. Researchers at CRREL have extensive experience testing US Army SUSVs and NATO Bv206s in cold regions and have documented the vehicles as one of the most capable in severe weather conditions ranging from flooding, deep mud or thawing ‘rasputitsa’, or deep snow. At the US Army Mountain Warfare School, the SUSV remains the vehicle of choice for search and rescue in extreme weather. The new prototype vehicles delivered to CRREL are based on the ST Engineering ‘Bronco’ All-Terrain Tracked Carrier (ATTC) currently in service by Singapore and Thailand militaries and previously deployed by the United Kingdom in Afghanistan. While the US Army ultimately selected the BAE Systems ‘Beowulf’ as the winner of the CATV program, the tractive performance has been identified by CRREL as comparable between the candidate vehicles with similar articulated quad track design and dimensions, ground pressure, and power delivery. By utilizing the prototype vehicles, researchers at CRREL will gain a head start toward characterizing the CATV in winter conditions before entering service in 2024. This paper will detail the experimental setup, analysis and results for testing conducted in 2023 in Dalton, New Hampshire as well as how the results will be used to begin updating current mobility prediction models. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 8672 / Trajectory optimization for vegetation override in off-road driving Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Trajectory optimization for vegetation override in off-road driving Authors: Charles Noren, Bhaskar Vundurthy, Sebastian Scherer, and Matthew Travers Abstract: Off-road robotic vehicles often encounter environmental objects while traversing complex terrains. These objects may obstruct the vehicle’s motion and must be perceived and reasoned about to ensure safe operation. Historically, limited sensing fidelity for autonomous vehicles led to either overly cautious or unnecessarily risky behaviors when interacting with environmental objects. Some objects must be avoided to ensure operational integrity, but avoiding all environmental objects will likely cause needlessly slow traversals. With contemporary sensing, the capability to tell the difference between these environmental objects is now possible. Given this improved sensing capability, developing controls algorithms which not only reason about avoiding certain classes of objects but can also reason about motions through other classes of objects is now the next step towards robust off-road autonomous driving. In this work, we propose a trajectory optimization technique for overriding vegetation that explicitly encodes contact constraints for a subset of vegetative objects found in the operating environment. The subset of objects that the vehicle can safely collide with is derived from existing parameterized collision models, the parameters of which are estimated by the on-board sensing system, and then characterized by a necessary velocity at the point of collision. These constraints are then enforced during vehicle run-time by the controller. The controller's capabilities are shown in both simulation and used to control a full-sized autonomous utility task vehicle. The vehicle’s determination to avoid or override objects is robust to uncertainty in the sensing system and is dependent on the specifics of the environment and object geometry. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 9268 / Experiments of sinkage characters of wire mesh wheel under different slip ratio Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Experiments of sinkage characters of wire mesh wheel under different slip ratio Authors: Wang Yang, Zou Meng, and Li Jianqiao Abstract: For researching the sinkage of the lunar rover on Earth, a soil bin test system under light-load conditions was developed, which was used for researching the soil-wheel interactions between the wire mesh wheel of rover and the lunar soil simulant. Results of the experiments of sinkage characters of wire mesh wheel under different slip ratio shown that: The sinkage increased with the increase of slip ratio, the height of rut decreased with the increase of slip ratio, while lunar soil simulant was under different prepared conditions; The sinkage and the height of rut both increased, when lunar soil simulant changed from compact to soft. Experiments of rut surface scan of wire mesh wheel shown that, the maximum sinkage of rut increased firstly and then decreased, the maximum negative sinkage of rut increased, the shearing action of terrain increased, the surface of rut was8 destroyed gradually, with the increase of slip ratio. The results provided basic experimental data for evaluating the sinkage of lunar rover and the physical and mechanical characteristics of lunar soil simulant through the rut of wire mesh wheel. Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # 9992 / Soil shear strength values obtained from its colour Paper presented at the 16th European-African Regional Conference of the ISTVS Title: Soil shear strength values obtained from its colour Authors: Alaa El Hariri and Peter Kiss Abstract: The soil shear strength and its parameters are important values that reflect the resistance of the soil to shearing. The soil shear strength relates the shear cohesion, internal friction angle, and the applied consolidation pressure through the linear Coulomb model. The paper embeds shear strength, shear cohesion, and internal friction angle results of a sandy loam soil and a clay soil at different moisture contents. The shear strength values were obtained using the direct shear test, also by drawing the Mohr-Coulomb line. Beside the mentioned values, the article contains colour results of the tested soil types at different moisture contents, measured using the spectrophotometric technology in the visible band (spectrum; 400-700 nm). Relating the colour of the soil to its shear strength values through its moisture content, might be helpful in the field for identifying the shear strength and its parameters based on the colour of the soil, and this target is achieved by laboratory empirical work. The process of correlating the soil colour and its shear strength values at different moisture contents is presented in the paper. The measurements were carried out at the Hungarian University of Agriculture and Life Sciences (MATE - Department of Vehicle Technology Laboratory). Order the full paper: ISTVS members: receive three papers per year as part of your membership via the ISTVS Member Portal: # Abstract-only submissions Abstract-only submissions to the 16th ISTVS European-African Regional Conference ### 1166 / Selection of energy saving engine mode based on the power delivery and fuel consumption of a 95-kW tractor during agricultural operations Md Abu Ayub Siddique, Seung-Min Baek, Mo-A Son, Ye-In Song, and Yong-Joo Kim Abstract: The objective of this article is to estimate the power delivery efficiency and fuel consumption based on engine modes. In this study, 95-kW powershift tractor was used to analyze the power delivery and estimate the fuel consumption during agricultural operations. The asphalt driving, plow and rotary tillage were conducted for the field the experiment at the engine modes of conventional, APS (Auto power shift) power, and APS ECO. To analyze the field condition, soil hardness, and soil water content were measured as well as soil sample was collected from the experimental site to analyze the soil texture using the USDA soil texture triangle. It is observed that the engine required powers at various engines have a significant different of the asphalt driving, plow, and rotary tillage. However, the axle powers at all engine modes for each operation showed almost similar due to the similar forward speed of the tractor. In case of fuel consumption, it was found that the fuel consumption at each engine mode has a significant different. It was also observed the APS ECO mode was the most economic compared to the conventional and APS power for the asphalt driving, plow and rotary tillage. Therefore, we recommend by this study to the users to perform the tractor at APS ECO engine mode for asphalt driving, plow, and rotary tillage considering fuel economic and high working load. ### 2297 / Traction effects on vertical and horizontal contact stresses and the risk of soil structure deformation Loraine ten Damme, Lars J. Munkholm, Per Schjønning, Thomas Keller, Alvaro Calleja Huerta, and Mathieu Lamandé Abstract: Arable soil is often exposed to high mechanical stresses during field operations, which bears a great risk of soil structure deformation. The stress state under the wheels determines whether a risk of soil compression and/or soil distortion prevails. However, soil compaction risk assessments typically consider the risk of compression from the applied load but neglect tractive forces and the risk of distortion. We investigated traction effects on both the vertical and horizontal (longitudinal) stress distributions near the tyre-soil interface as a next step in advancing more accurate predictions of soil structure deformation. Vertical and horizontal stress measurements were made during wheeling in a field experiment with stress transducers installed at 0.1 m depth. We studied the stress distributions of a tractor’s rear wheel (6.7 Mg, 650/60 R38, 80 kPa) that was towed (i.e., no traction) or pulling (i.e., with traction, about 42 kN drawbar pull) and compared these with estimated soil strengths. We show how traction influenced tyre-soil interaction and the risk of soil structure deformation. Among others, with traction the tyre-soil contact area was larger and the magnitude of vertical stress lower. This reduced the risk of soil compression noticeably. Soil shear strength was reduced due to reduced constraining normal load. The latter, in combination with higher horizontal stresses, increased the risk of soil distortion considerably. Our results highlight the importance of considering traction in soil compaction risk assessments. However, reliable assessments require incorporation of the risk of soil distortion in addition to the risk of soil compression. ### 3815 / Data measurement and performance evaluation of an electric all-wheel-drive tractor during plow tillage Seung-Yun Baek, Yong-Joo Kim, Seung-Min Baek, Ji-Won Choi, and Min-Jong Park Abstract: This study was conducted for basic research on AWD (all wheel drive) systems applicable to tractors as the need for research on electric AWD systems increases. The platform consists of an electric power transmission system consisting of 4 sets of electric motors, helical reducers and planetary reducers, wheels, and an electric system including chargers, batteries (LiFePO4), converters and inverter (motor controller). The data measurement system consisted of analog (current, traction force) and digital (battery voltage, current, motor rotation speed, SOC (state of charge) level, travel speed) components using a CAN (controller area network) bus. Data measured during plow tillage were analyzed and used to calculate the data such as motor power, motor torque, traction power, and driving power. The traction performance of the electric AWD tractor was evaluated using tractive efficiency (TE) using calculated values (traction power and driving power) and dynamic ratio (DR). This study presented limitations and improvement methods of electric AWD tractors through data analysis and comparison with conventional tractors. In future study, we plan to conduct research on optimization and performance verification of the electric AWD tractor that reflect improvements. ### 3859 / Analysis for dynamic characteristics of a tractor cabin during agricultural operations Jong-Dae Park, Hyeon-Ho Jeon, Su-Young Yoon, Min-Jong Park, and Yong-Joo Kim Abstract: This study was conducted to develop a dynamic characteristic control system for improving the cabin environment during agricultural operations. The specification of platform used in the study was a 67 kWclass tractor with a weight of 4,000 kg and dimensions of 4,020 × 2,270 × 2,790 mm (lenth × width × height), respectively. For measuring data of dynamic characteristic of the cabin, plow tillage and rotary tillage, which account for the largest proportion of the tractor operations, were selected for major operations. To measure data of dynamic characteristic of the cabin, which continuously changes during operations, an Ellipse Series INS with a built-in IMU was attached to the center of gravity of the cabin. During field test, the gear stages of plow tillage were B2 (5.1 km/h) and B3 (7.6 km/h), and the gear stages of rotary tillage were A3 (2.67 km/h) and A4 (3.66 km/h), which are the most commonly used. To analyze dynamic characteristic such as roll and pitch during operations according to the gear stages, the data showed by box plot. Roll and pitch average angles were -0.7° and 0.4°, respectively, for the plow tillage. Roll and pitch average angles were -0.8° and -0.1°, respectively, for the rotary tillage. As operations rate increased, the roll and pitch angles became larger, varying within a maximum range of 2°. As a result, it was determined that the rotary tillage showed a larger change compared to the plow tillage in the case of roll. Both operations showed a similar change in the case of pitch. Also, roll and pitch showed a larger change as the travel speed of each operation increased. In the future, we plan to conduct additional research on the hydraulic control system related to the cabin to provide a more comfortable workspace for operators. ### 3893 / Analysis of load factor and performance evaluation for developing an electric driven tractor Min-Jong Park, Su-Young Yoon, Ji-Won Choi, Jong-Dae Park, and Yong-Joo Kim Abstract: This study aims to develop a 44 kW electric driven tractor consisting of an E-driving system. Because electric tractor is in the design process, we installed a measurement system on a conventional agricultural tractor. Torquemeters were installed between wheels and axles to measure wheel torque, proximity sensors were installed to measure wheel rotation speed and GPS (Global Positioning System) was installed to measure driving speed of the tractor. Antenna, amplifier, and DAQ (Data Acquisition) were installed to transfer and store the measured data. Workload data were measured during plow tillage, rotary tillage, loader operations, asphalt and field driving. Measured data were converted for validation of designing a 44 kW electric driven tractor using an engine load factor. The average engine load factor was 0.51 for rotary tillage, 0.46 for plow tillage, 0.38 for asphalt driving, 0.17 for field driving and 0.09 for load operation. For gear stage L, plow tillage and loader operations were conducted within the maximum torque and rotary tillage, field and asphalt driving were performed within the rated torque. For gear stage M, the plow tillage and loader operations were conducted outside of the maximum torque, which were impossible to perform. For gear stage H, all operations except the asphalt driving were conducted outside of the maximum torque, which were impossible to perform. Thus, high-load operations such as plow tillage and loader operations can be conducted in gear stage L, and high-speed operations such as asphalt driving can be conducted with motor rated speed in gear stage H. Consequently, it is judged that an E-driving system consisting of a motor and range shift can perform the major operations of a 44 kW tractor depending on gear stages. ### 4336 / High-fidelity 3D-DEM simulation for wheel mobility in low gravity environment Takuya Omura and Genya Ishigami Abstract: The effect of gravity on wheeled rover mobility on loose soil remains a challenging issue. Among several experimental techniques, such as parabolic flight or reduced-weight tests simulating low gravity, the discrete element method (DEM) is one of the most promising methods for analyzing the wheel-soil interaction in various gravity environments. However, the mechanical parameters used in the DEM are often identified ambiguously or empirically, resulting in low-fidelity simulation results. In this study, we comprehensively calibrate the mechanical parameters of a lunar regolith simulant applicable to the 3D-DEM to simulate the effect of gravity on wheel mobility. The DEM parameters were determined from the experimental results of two tests: the direct shear test and the minimum density test. We then tested a rigid wheel on the lunar simulant using the DEM with calibrated parameters in the following conditions: (1) Earth gravity (1 G) with the wheel mass of M, (2) moon gravity (1/6 G) with the wheel mass of M, and (3) Earth gravity (1 G) with the reduced-mass of 1/6M. The simulation results show that the wheel sinkage and the slip ratio on the moon are almost equivalent to those on Earth. On the other hand, in the reduced-weight test, the wheel sinkage and the slip ratio were smaller than the moon's results. This result implies that the reduced-weight test might overestimate the wheel performance. ### 4508 / Semi-empirical terramechanics model for variable terrain height Eric Karpman, Jozsef Kovecses, and Marek Teichmann Abstract: Dynamic simulations of various types of off-road vehicles, from planetary rovers to agricultural equipment, have long relied on well-established semi-empirical terramechanics models. While these models do have drawbacks and reliability issues that have been addressed by numerous works in the decades since the models were first introduced, semi-empirical approaches remain one of the few ways to simulate realistic wheel-soil interaction in real-time. One of the drawbacks of these methods is that they are constrained by the assumption that the terrain is a flat plane. The models work by integrating normal and shear stresses along the wheel-terrain contact patch. The normal stress at each point along the contact patch is determined based on an equation that computes soil pressure based on semi-empirical parameters, the dimensions of the wheel and the sinkage of the wheel at that point. The sinkage at any given point along the contact patch is generally determined based on the distance between the point and the flat plane that defines the terrain. This means that the sinkage of each point along the contact patch is computed based on one constant initial terrain height. In this work, we propose a modified version of the semi-empirical model in which the terrain is defined as a height-field rather than a flat plane. Thus, more complex terrain shapes can be used in simulation. Of particular interests are terrains with varying slopes, steps, and terrain shapes that would result in gaps in the wheel-soil contact patch rather than a continuous patch. ### 4727 / Analysis of gear durability for agricultural tractor transmission Seungmin Baek, Seungyun Baek, Hyeonho Jeon, and Yongjoo Kim Abstract: The purpose of this study was to analyze gear durability of tractor transmission using simulation analysis. A field test was performed using a 86 kW class tractor and the type of gear failure was analyzed. A simulation model of the tractor transmission was developed and analyzed for the safety factor and lifespan by changing the material of the damaged gear. The field test was conducted for plow and rotary tillage and was completed after about 107 hours due to operational problems. After field test, it was found that range shift A and B gears were damaged. In order to advance durability of the transmission, four materials of alloy steel for machine structural use such as SCr420, SNCM220, SCM822, and SNC815 were selected, and the safety factor and service life of the damaged range shift gears were analyzed according to gear materials. As a result of simulation analysis, SCM822 material satisfied the target life and was selected as a material for change. Therefore, it is considered that the durability of the transmission has been secured by satisfying the target life. ### 4895 / Theoretical analysis and fem simulation of the interfacial forces between tracked vehicle and snow soil Yan Qingdong, Zhu Ming, Wei Wei, Liu Cheng, Liu Jianfen, and Meng Qingkai Abstract: Based on the pressure-sinkage characteristics and the shear force-shear displacement characteristics of snow under loading, unloading and reloading, theoretical models of vertical displacement distribution and vertical pressure distribution for snow and interfacial forces between track and snow under different driving conditions were built. A multi-body dynamics model of track and plastic material models of snow were built to simulate the interfacial forces of the track on snow. The results of plastic deformation and vertical pressure distribution of snow were extracted from the simulation results to verify the theoretical models. A muti-body dynamics model of articulated tracked vehicles was built, and the driving performance of it on snow was evaluated. An experimental study on articulated tracked vehicle driving in snow is carried out. By comparing the experimental results and the simulation results of the plastic deformation characteristics of snow under tracked vehicle loading, the correctness of the coupling simulation model and the theoretical model is verified. ### 4976 / Performance evaluation of autonomous driving lateral control simulation model of agricultural tractor Moa Son, Hyeonho Jeon, Seungyun Baek, Yein Song, and Yongjoo Kim Abstract: Interest in automation of agricultural machinery is increasing. Recently, performance evaluation studies using simulation models are being conducted to reduce time and cost. Therefore, in this study, the performance evaluation of the autonomous control model of an agricultural tractor was performed. The simulation model was developed using the specifications of a 78 kW tractor and the software RecurDyn. The input data was set as traction data from the six-component load cells, the rotational speed of each axle, and the position of the 3-point hitch. Validation of the simulation model was conducted by comparing the error between the measured data and simulation results. The performance evaluation of the steering control model was performed on the road model (friction coefficient conversion). The steering control model was configured to perform steering control by receiving the lateral error in real time from the dynamics model. A trial-and-error method was used to select coefficients for the autonomous control model. The RMS of the measured data was 3.29 and 3.44 for the anterior left and right sides, respectively, and 6.98 and 7.41 for the posterior left and right sides, respectively. The RMS of the simulation results were 3.24 and 3.53 for the anterior left and right side, respectively, and 8.26 and 8.55 for the posterior left and right side, respectively. The errors were 1% and 2% for the anterior left and right side, respectively, and 15% and 13% for the posterior left and right side, respectively. The error occurred within the range of about 10%, and it was judged appropriate to conduct research on performance evaluation using this model. The RMS according to the friction coefficient conversion was 3.7 and 4.5, respectively, showing a difference of about 1. ### 5356 / Development and validation of head-feeding combine harvester multibody dynamics simulation model Cheol-Woo Yang, Hyeon-Ho Jeon, Min-Jong Park, Ji-Won Choi, and Yong-Joo Kim Abstract: Head-feeding combine harvester are expensive and time-consuming to produce prototype, performance evaluation using simulation should be performed in the design stage. Recently, research has been conducted to solve these problems by replacing the driving test of agricultural machinery with simulation. In this study, a head-feeding combine harvester dynamics simulation model was developed and verified. The simulation model was developed using commercial software (Recurdyn, V9R4, Korea). The model development was performed using the specifications of a 6-row head-feeding combine harvester (CF690G, TYM, Korea). The speed condition of the simulation was set to 1.5 m/s. The simulation result set as the torque of the sprocket. For the development and validation of the simulation model, a measurement system was developed and installed on the head-feeding combine harvester. The driving test was conducted at the paddy field located in Dangjin, Chungnam (36°55'49.1"N, 126°37'57.3"E). The simulation was verified by comparing the measured data with the simulation results. The simulation results showed an average sprocket torque of approximately 1241.17 Nm. The measurement resulted in an average sprocket torque of approximately 1143.49 Nm. The error between the measured and simulated values is around 7%, and the measured and simulated values are similar. In the future research, the study to measure the load data during agricultural work and improve the simulation model using the load data will be conducted. ### 6059 / Comparison of multi-tracked running gears for light UGVs in terms of terrain obstacles overcoming abilities Daniela Szpaczyńska, Marian Łopatka, and Piotr Krogul Abstract: Rubber tracked running gears are widely used in high-mobility unmanned ground vehicle to increase the ability to overcome terrain obstacles that are often found in off-road terrain. The paper investigates the process of overcoming an obstacle by light unmanned ground vehicle using multibody dynamics simulations. The two-dimentional model of running gear was assumed and created in the ADAMS program environment. As well as the kinematics of the running system components, the flexibility of the elastomer belt and also the reactions of the tractive force in the track-ground contact surface were taken into account. On the basis of the simulations, the functionality of multi-track systems was compared with classic tracked systems. Properties that could be improved through the use of multi-tracked running gears in light land platforms were determined. ### 6143 / Flexible tire-terrain interaction model for real time simulations Mahdi Maleki and Jozsef Kovecses Abstract: The analysis of tire dynamics is important in the simulation of vehicle behaviours. The forces exerted on a tire depend on the tire and the terrain interaction at the contact patch, and the tire structure directly influences this interaction. Complex models with a high number of degrees of freedom, such as lumped parameter models or finite element models, are typically required to represent tire flexibility appropriately. Employing these models, however, can lead to high computational costs that can be a significant challenge for real-time simulation. In this work, we developed a reduced flexible tire model capable of representing the effect of tire flexibility to reduce the computational costs of the simulation. This model reduction is done by defining an effective stiffness of the flexible tire (which accounts for the effects of tire deformation at the contact patch) and augmenting it with the rigid wheel to represent the effect of stiffness at the contact patch. The flexible tire model, which has been used as a base, is a lumped parameter model in which the tire sidewall and belt are represented by a set of lumped point masses connected together and to the rigid wheel rim with sets of parallel spring and damper elements. In addition to reducing the degrees of freedom of the system, the proposed method makes it possible to perform the simulation with relatively large time steps, which significantly reduces the simulation run time. By this approach, we could achieve up to 25 times faster simulations compared to the ordinary model while maintaining adequate accuracy. ### 6211 / Wheel-soil terramechanics model augmentation using machine learning across multiple soil types Eric Karpman, Jozsef Kovecses, and Marek Teichmann Abstract: Terramechanics simulations for real time applications have primarily made use of traditional semi-empirical models since they are the only ones computationally efficient enough to run at real time interactive rates. A drawback to these models is that they are formulated based on an assumption that the wheel is operating under steady state conditions. This can adversely affect their accuracy or even their compatibility in dynamic simulations. Computationally demanding approaches such as the Finite Element Method (FEM) and the Discrete Element Method (DEM) address this issue, but the time required to run simulations is prohibitive for certain applications. We have previously proposed a method for real time terramechanics simulation that addressed the issue of the steady state assumption in the traditional semi-empirical models by using machine learning (ML) to augment the forces predicted by existing semi-empirical models in an effort to improve accuracy in dynamic simulations. By augmenting the semi-empirical predictions with ML rather than using ML to predict the total force, we aimed to preserve the insights provided by the semi empirical model. DEM experiments were run to establish a ground truth for the soil reaction forces, and at each time step we compared predictions of the semi-empirical model to those recorded in DEM simulations. We then train a ML model to augment the semi-empirical model to match DEM results. Our past work showed how this approach can work for a single soil type. Now, we will present the work with an expanded scope in which multiple soil types are used to train the ML algorithm - resulting in a single trained model that can be used for a variety of different soil types without the need to re-train the ML portion of the model each time. ### 6955 / Development of dynamics simulation model for agricultural tractor according to agricultural work Hyeonho Jeon, Seungyun Baek, Seungmin Baek, Moa Son, and Yongjoo Kim Abstract: The behavior of tractor is affected by the load. Especially, the behavior is significantly changed, an accident, such as rollover, is occurring. Therefore, the behavior of the vehicle affects work stability. To increase the work stability, it is necessary to predict the behavior of the vehicle by predicting the load occurred in a vehicle. This study was conducted as a basic study for the development of a tractor dynamics model. The simulation model was developed using a multi-body dynamics software and a steering controller for a simulation model. The specification of the tractor was 4,225 mm in length, 2,140 mm in width, 2,830 mm in height, and 3,985 kg. The center of gravity was 984 mm from the rear axle, 973 mm above ground, and 986 mm from the left side of the vehicle. Simulations were conducted during conditions of Plough tillage and condition of driving on a field. A field test was conducted to make and validate the simulation model. The measurement system is configured to measure traction, rotation speed, axle torque and behavior of a tractor. Traction and axle rotation speed were used as input data for simulation model. The load on axles and vehicle behavior were used as validation data for simulation. Field tests were conducted to measure input value and verify the simulation model. Field tests were conducted at M2 high (5.2 km/h \~ 6.7 km/h). Analysis between simulation result and measurement data showed that the difference in axle load was less than 10%. The load on axles can be predicted by using the developed model and evaluating the steering controller model can be conducted using this dynamics simulation model. In the next study, it is necessary to evaluate the steering controller model thorough the dynamics model. ### 7994 / Longitudinal friction coefficient comparison on actual and laboratory surfaces Carl Becker and Schalk Els Abstract: Tyre models used in soft soil simulation analysis requires tyre parameters in the form of stiffnesses in multiple di-rections. These parameters are obtained from measurements on hard terrain as these parameters are a function of the tyre carcass construction. Vehicles used on soft terrain are also used on hard terrain. Tyre testing is not a trivial or inex-pensive exercise and outdoor testing has limitations on repeatability. This is the case for testing on soft terrain/soil and hard terrain, thus it is preferred to conduct laboratory tests when characterizing tyres. This study investigates the longi-tudinal friction coefficient measured on surfaces with different surface roughness. The surface roughness has a direct influence on the friction coefficient generated by a tyre during tests. Tests are conducted on the actual concrete surface of interest, typically used in field tests. A mold is cast from the actual surface in order to replicate the same surface in laboratory conditions. Tests are then conducted on the replicat-ed surface and different sandpaper surfaces to determine which surface is the most representative in the laboratory. Multiple tyres are tested on the different surfaces and results compared. ### 8754 / Characterization of lunar simulant (FJS-1), toyoura sand, and silica sand with physical experiments and dem simulation Isabel Casasbuenas, James Hurrell, Keisuke Takehana, and Kazuya Yoshida Abstract: Geotechnical properties of the soils allow understanding of the mechanical behavior of soil under different stress conditions. However, the geomechanical properties of soils under Earth’s gravity are liable to be different from those under lunar gravity, making direct comparisons with experiments difficult. Therefore, Discrete Element Method (DEM) simulations can be used alongside physical experiments to study the geotechnical properties of the soil in a lunar environment. Understanding the mechanical behavior of the lunar soil will aid in performing future engineering operations such as mobility, construction, mining, and foundation design. Angle of Repose and Triaxial compression test simulations in lunar and terrestrial gravity environments were performed to understand soil behavior under these two environments. Angle of repose (AoR) testing used the fixed funnel method. A set volume and mass of material are poured through a funnel forming a pile below. A value is then measured for AoR which is related to the internal friction angle. Laboratory triaxial tests were performed on three specimens to simulate stress conditions and determine shear strength and other geotechnical properties under Earth’s gravity conditions. Vertical loads were applied at a 0.5 mm/min rate and confinement pressure from 10 to 60 kPa. Cohesion, soil stiffness, shear stress, and friction angle obtained from the triaxial and angle of repose tests are compared with the results obtained in DEM simulations. Exploring the difference between static and dynamic tests could contribute to understanding where physical properties of the lunar soil play a major role in the wheel soil interaction. The result of the present work will contribute to ongoing research in wheel-soil interaction. ### 8859 / An efficient and high-fidelity track model for dynamic simulation of off-road tracked vehicles Oz Ben-Yosef and Dror Rubinstein Abstract: A high-fidelity simulation model of tracked vehicles is required for proper prediction of the mobility of tracked vehicles traveling over soft soils. The vehicle components can be modelled using standard tools of multi-body programs. A track model was developed and successfully worked together with Altair's MotionSolve multi-body program. The model based on classic soil mechanics equations. The grousers, which are a significant part of many types of track-links, are taking into the account. The plasticity and viscosity properties of the soil are considered in the model. Verification tests were conducted in an agricultural field in the Jezreel Valley. The tests were run over soils with varying mechanical prop-erties, achieved through irrigation and tillage. The chosen test vehicle was an M113 armoured carrier. Several drawbar pull loads were applied on each soil condition. Reasonable correlation between the tests and simulation results were achieved. However, this model is not efficient and require consumption of large amount of CPU time. On the other hand, the more efficient models are based on simplifying assumptions with lack of accuracy. This work proposes a method for creating an efficient high-fidelity model. This can be implemented by representing the interaction between the track and the ground according to the previous work. The solution for the track-links will be done independently to the solu-tion of the entire vehicle. The solution of the track link will be obtained through a solver that will be developed for this purpose. The solution of the entire vehicle will be done by the solver of the multibody program (Altair MotionSolve). Good correlation between the efficient model and the previous model were achieved. ### 8963 / Analysis of the influence of terrain unevenness and velocity on the ground pressure exerted by demining rollers Dariusz Kalinko, Marian Janusz Łopatka, Arkadiusz Rubiec, Mirosław Przybysz, and Piotr Krogul Abstract: The effectiveness of demining rollers heavily depends on their performance in different terrains and operating conditions. Conventional demining roller structures with rigid wheels are widely used in demining operations, but their performance in real work conditions is still a significant scientific aspect. In this paper, the results of simulation tests conducted on demining roller systems with rigid wheels, without additional ground pressure systems are presented. A multi-body numerical model of a vehicle with a single demining section is described. The influence of terrain unevenness and velocity on the ground pressure exerted by roller is discussed. ### 9504 / Soil deformation model for efficient simulation of off-road vehicles and compaction force analysis Yang Jiao and Jozsef Kovecses Abstract: The performance evaluation of off-road vehicles is important since their operating environment is always complex. There are various types of models developed to predict vehicle soil interaction, ranges from semi-empirical models to discrete element(DEM) finite element based representations. For scenarios that require fast simulation, semi-empirical model is a better choice since it has the lowest computational cost. However, it does not incorporate the influence of soil deformation and has a quasi-static nature. To incorporate the influence of soil deformation, a new soil deformation model is proposed and developed. The geometry of the soil in this model is represented by using a height map with vertical layers. The soil deformation is separated into two parts and the total soil mass is conserved. The soil mass transmission resulted by vertical soil compaction is the main focus of this work, and it is captured by using a soil mass prediction neural network. The change in density and void ratio on each soil layer is then computed based on the mass transmission. The other part that resulted by tangential movements would also be briefly introduced. The data gathering is done by conducting Bevameter tests in DEM simulation environment by using EDEM. Various compaction tool widths, speeds and angles are used to generate the data for training and validation purposes. The influence of the compaction speed and angle on soil compaction force and soil skeleton states (e.g. density and void ratio at each layer) are also analyzed to investigate the possibility of optimizing the prediction of the Bekker pressure sinkage equation and the soil deformation model. The relation between Bekker parameters and general soil mechanics parameters is also discussed in this work. ### 9716 / Non-pneumatic tire for special vehicle – a review of selected functional properties Marcin Żmuda, Jerzy Jackowski and Marcin Wieczorek Abstract: The wheel is an important element of the vehicle, as it is the only one that has direct contact with the road. Pneumatic tires are the most commonly used on vehicles nowadays. The tires transfer traction forces and directional control of the vehicle, they affect on parameters of the contact patch and the enveloping properties. Those functions of tires require maintaining compressed air at a certain pressure inside the pneumatic tire. Losses of compressed air, as a result of damage to a pneumatic tire, makes it difficult or impossible to use it further. High reliability of tires and resistance to damage is particularly important in the case of special vehicles that move mainly in difficult terrain, e.g. soft soil, natural and artificial obstacles, objects with sharp edges. In those conditions, an alternative solution are non-pneumatic-tires, in which the function of compressed air has been taken over by the so-called supporting structure. Type of supporting structure, including shape and materials used, influence on the load -carrying mechanism, directional stiffness and pressures in the contact patch. The paper analyzes the method of shaping selected properties of non-pneumatic tires and the influence of the applied supporting structure on selected operational characteristics of non-pneumatic tires. # Editorial Board Editorial board for the Conference book of proceedings **Jarosław Pytka**, [Lublin University of Technology](https://2023.istvs.org/proceedings/www.pollub.pl/en), Poland, *Chair*\ **Dariusz Błażejczak**, [West Pomeranian University of Technology](https://2023.istvs.org/proceedings/www.zut.edu.pl/EN/university.html), Poland\ **Piotr Budzyński**, [Lublin University of Technology](https://2023.istvs.org/proceedings/www.pollub.pl/en), Poland\ **Schalk Els**, [University of Pretoria](https://2023.istvs.org/proceedings/www.up.ac.za), South Africa\ **Rámon Gonzalez**, [robonity](https://2023.istvs.org/proceedings/www.robonity.com/index.html), Spain\ **Bradley Hansen**, [US Army Corps of Engineers,](https://2023.istvs.org/proceedings/www.usace.army.mil) U.S.A.\ **Rainer Horn**, [CAU Kiel](https://2023.istvs.org/proceedings/www.uni-kiel.de/en), Germany\ **Heidi R. Howard**, [US Army Corps of Engineers,](https://2023.istvs.org/proceedings/www.usace.army.mil) U.S.A.\ **Genya Ishigami**, [Keio University](https://2023.istvs.org/proceedings/www.keio.ac.jp/en), Japan\ **Jerzy Józwik**, [Lublin University of Technology](https://2023.istvs.org/proceedings/www.pollub.pl/en), Poland\ **Thomas Keller**, [Swedish University of Agricultural Sciences](https://2023.istvs.org/proceedings/www.slu.se/en), Sweden\ **Peter Kiss**, [Hungarian University of Agriculture and Life Sciences](https://2023.istvs.org/proceedings/www.en.uni-mate.hu), Hungary\ **József Kövecses**, [McGill University](https://2023.istvs.org/proceedings/www.mcgill.ca), Canada\ **George Mason**, [Mississippi State University](https://2023.istvs.org/proceedings/www.msstate.edu), U.S.A.\ **Massimo Martelli**, [National Research Council](https://www.cnr.it/en), Italy\ **Lutz Richter**, [SoftServe, Inc.](https://www.softserveinc.com/en-us), Germany\ **Dror Rubinstein**, [Ariel University](https://2023.istvs.org/proceedings/www.ariel.ac.il/wp/en), Israel\ **Vilas M. Salokhe**, [Kaziranga University](https://2023.istvs.org/proceedings/www.kzu.ac.in), India\ **Corina Sandu**, [Virginia Tech](https://2023.istvs.org/proceedings/www.vt.edu), U.S.A.\ **Przemysław Simiński**, [University of Natural Sciences and Humanities](https://2023.istvs.org/proceedings/www.uph.edu.pl/en), Poland\ **Thomas R. Way**, [USDA-ARS, National Soil Dynamics Lab](https://2023.istvs.org/proceedings/www.ars.usda.gov/southeast-area/auburn-al/soil-dynamics-research), U.S.A.\ **Vladimir Vantsevich**, [Worcester Polytechnic Institute](https://2023.istvs.org/proceedings/www.wpi.edu), U.S.A.\ **Artur Zdunek**, [Institute of Agrophysics PAS](https://2023.istvs.org/proceedings/www.ipan.lublin.pl/en), Poland # Book of Proceedings *Proceedings of the 16th European-African Regional Conference of the ISTVS* ISBN 978-1-942112-55-6 (pdf)