Dynamic Modeling and Sliding Mode Driving Control for Lunar Rover Slip

Slip ratio is the crucial variable of the interaction between wheels and soft road. Based on the definition of the slip ratio of wheels, dynamical model of the lunar rover is established in this paper, which incorporated the terramechanics theory. We calibrated some parameters of soil according to the theory of muti-pass performance of rigid driving wheels. Considering uncertainties of the non-linear model, the sliding mode controller is designed. Simulation results shows that the controller effectively keeps the slip rate of the wheel tracking the desired value and avoids the excessive spin and sink of the driving wheel.