Trajectory Control and Sensitivity Analysis of Curiosity Rover on Uneven Terrains

Abstract

In this paper, the six-wheel lunar rover is simulated in Adams/View software environment and then via co-simulation between adams and matlab/simulink with which a path-following controller is designed and implemented on the rocker-bogie mechanism. The proposed algorithm consists of three parts. First, the inverse kinematic equations are used to transform the trajectory into appropriate desired values. Second, a sliding mode controller (SMC) is designed which used the desired values to control the motion of the robot. Moreover, disturbances are taken into consideration to minimize the lateral error. In order to investigate the proposed integrated algorithm, the analysis of rover traversability on the uneven surface of the moon is performed in two different states, namely by considering the motion restrictions of the rocker-bogie mechanisms and by increasing the rover speed, body yaw angle, and also obstacle height in crossing the rough terrain. Investigation of the rover in different states has given insight on the performance of the proposed controller at limits of mobility of the robot. Finally, to reduce the battery energy consumption, input torques proportional to the load on the wheels are produced. The values of the deviations from the desired path and velocity in all the mentioned analyses indicate the effectiveness of the SMC.