松软地质上机器人足-地动力学建模与试验

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.