Abstract

In this paper, a new approach to modelling the dynamics of the Pioneer-3AT robot on planetary soil is presented. This model is used to design a robust traction control algorithm that makes use of the Sliding Mode Control (SMC), the Artificial Potential Field (APF) and a Fethi Beckoche navigation function for collision avoidance with predefined obstacles. Simulations were carried out for swarms of micro-rovers using the parameters of an in-house planetary soil simulant. The controller was designed to control the wheel movements of the robot on an unstructured environment using the SMC and APF. Simulation results show that the controller and the navigation function effectively achieves the permitted slip rate, sinkage, angular and longitudinal velocities, sliding surface and torque for the wheels, thus offering efficient traction while avoiding the excessive wheel slip and sinkage.