Evaluation of the shear deformation model in the process of wheel sinking by the wheel experiment

Abstract

Soft soils cover on planetary surfaces, so the wheels for exploration rovers easily slip. Understanding an interaction between a wheel and soft soils is important for a traction control to improve rover traversability. The interaction between the wheel and soft soils has been studied in a field of terramechanics. Since the classical terramechanics-based wheel model considers only a static state of a wheel sinkage, the wheel model is not applicable to the wheel sinkage and slip. Thus the dynamic normal stress model and shear deformation model were proposed to deal with the problems of the wheel sinkage and the slip. The dynamic normal stress model was proposed by considering the wheel sinking velocity and a variation of soil state for solving the problem of wheel sinkage. And the shear deformation model was proposed by considering the shear characteristics for solving the problem of wheel slip. The shear deformation model was formulated by the shear test. The simulation verified the validity of the dynamic normal stress model and the shear deformation model in the transient state. In this paper, a single wheel experiments was performed to evaluate the shear deformation model by comparing the simulation results and the experimental results. Then the characteristics of the wheel sinkage and slip and the effectiveness of the model were confirmed.

Keywords

• wheel dynamic sinkage
• shear deformation modulus
• wheel acceleration
• wheel experiment