Tracking Control And Point Stabilization Of The Lunar Rover

This paper addressed three problems for a nonholonomic mobile robot. First, dynamics model of a six-wheeled rocker lunar rover is built. Then based on this model the control strategies are proposed for trajectory tracking control and point stabilization.Dynamics mathematic model for the mobile robot is built based on the analysis of the mechanism of a six-wheeled rocker lunar rover. Because the steering angles of front wheel and rear wheel couple with the directional angles, a kinematics approach is developed to compute these two steering angles. Based on the computed steering angles this paper builds lunar rover's mathematic model using Lagrange function.Based on the built mathematic model for lunar robber a two-closed-loop tracking control strategy is proposed. This proposed strategy applies single neural sliding mode control method for nonhomonomic constraints, fuzzy control method for uncertain conditions and Lagrange optimization calculation for the redundancy of the inputs. The parameters of single neural sliding mode controllers are determined by genetic algorithm. Simulation results show the proposed control strategy can tracking the expected trajectories.Considered a fact that the lunar rover has no capability to turn around in a point, a hybrid controller is proposed for the rover to stabilize it to the expected point. This controller is designed to stabilize angle error, front error and side error separately based on the kinematic model of the rover. The simulation results show the lunar rover can be stabilized to expected point by our proposed method.