Modeling and Verification of Robot Foot-terrain Dynamics in Soft Geology

doi:10.3901/JME.2022.05.008

Abstract

Abstract: Foot-terrain dynamics is the core of the movement mechanism of multi-legged robot in soft geology and it also plays an important role in its design, simulation and motion control. Considering that the tangential motion compresses the soil around the foot end, the dynamic model of flat foot-terrain is established by combining the theory of terramechanics and Rankine passive earth pressure theory. Furthermore, a rectangular foot ground dynamic model with a certain inclination angle is established. A special foot-terrain interaction test system is built and the parameters measured by the pressure plate experiment are substituted into the rectangular foot-terrain dynamic model. Compared the theoretical value with the experimental value and the prediction error is within a reasonable range. The experimental data of different foot pose angles are identified by nonlinear fitting and we can obtain the stress-strain coefficients of thrust and bearing capacity. The minimum error is 9.89%, which verifies the validity of the establishment of the stress distribution function of the flat foot.

Key words: foot-terrain dynamics, legged robot, soft geology, foot-terrain interaction test, parameter identification

CLC Number:

TP242

LIU Yi-qun, LU Pei-dong, ZHANG Zhi-peng, WANG Jian-feng, ZHANG Jing-ming, DING Liang, GAO Hai-bo. Modeling and Verification of Robot Foot-terrain Dynamics in Soft Geology[J]. Journal of Mechanical Engineering, 2022, 58(5): 8-17.

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