Abstract
Developing new concepts for the prediction of off-road traction is becoming essential as an increasing number of sport utility vehicles (SUVs), sport activity vehicles (SAVs), and other off-road vehicles arrive on the market. The prediction of off-road traction is a difficult problem because of the number of factors affecting wheel performance on soft soils or snow. Most of the existing methods for wheel-soil thrust prediction are based on Coulomb’s equation, in which stresses acting on the wheel-soil contact patch are analyzed. The objective of this work was to develop a new method to infer mathematical models of a wheel-soil system in which soil-stress states are correlated with the forces acting on a road wheel. A set of model equations is obtained by means of the system identification method with the use of experimental data gathered in the field with real vehicles. This paper includes a description of the experimental setup, procedures, and methods used in the tests. The experimental method is based on simultaneous measurements of the soil-stress state and wheel forces during test runs of an instrumented vehicle over soft soil surfaces. Soil-stress states consist of three principal stresses and their direction cosines, which are determined with the use of a stress state transducer (SST) placed at a depth of 15–30 cm under the wheels. Longitudinal, vertical, and transverse wheel forces are measured with a six-element wheel force transducer. The wheel forces obtained in the test runs are correlated with the respective soil stresses. Based on the data, three families of models were obtained by means of the system identification method.
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References
Bekker, M. G. (1969). Introduction to Terrain — Vehicle System. The University of Michigan Press. Ann Arbor.
Godbole, R., Alcock, R. and Hettiaratchi, D. (1993). The prediction of tractive performance on soil surface. J. Terramechanics 30,6, 443–459.
Klein, V. and Morelli, E. A. (2006). Aircraft System Identification. Theory and Practice. AIAA Education Series. Reston. Virginia. USA.
Ljung, L. (1999). System Identification. A Theory for the User. Prentice Hall. New York.
James, S. R. (2002). Lateral dynamics of an offroad motorcycle by system identification. Vehicle System Dynamics 38,1, 1–22.
Muro, T. (1993). Tractive performance of a driven ridig wheel on soft ground based on the analysis of soil — wheel interaction. J. Terramechanics 30,5, 351–369.
Pytka, J. and Dąbrowski J. (2001). Determination of the stress-strain relationship for sandy soil in field experiments. J. Terramechanics, 38, 185–200.
Pytka, J. (2005). Effects of repeated rolling of agricultural tractors on soil stress and deformation state in sand and loess. Soil & Tillage Research, 82, 77–88.
Pytka, J. (2008). A wheel dynamometer for off-road vehicle testing. SAE Paper No. 2008-01-0783.
Pytka, J. (2009). Determining and analyzing the stress state under wheeled vehicle loads. J. Automobile Engineering, 222, 233–254.
Wanjii, S., Hiroma, T., Ota, Y. and Kataoka, T. (1997). Prediction of wheel performance by analysis of normal and tangential stress distributions under the wheel — soil interface. J. Terramechanics 34,3, 165–186.
Wulfsohn, D. and Upadhyaya, S. (1992). Prediction of traction and soil compaction using three-dimensional soil — tyre contact profile. J. Terramechanics 29,6, 541–553.
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Pytka, J.A. Semiempirical model of a wheel-soil system. Int.J Automot. Technol. 11, 681–690 (2010). https://doi.org/10.1007/s12239-010-0081-6
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DOI: https://doi.org/10.1007/s12239-010-0081-6