Research On Configuration And Trajectory Optimization Control Of Mars Rover In Unstructured Environment

The Mars is covered with sand and stone,which is a typical unstructured terrain.In this paper,the Mars rover with active suspension is taken as the research object.Aiming at the problem of the moving performance of the Mars rover with active suspension in the unstructured environment,this paper proposes the optimal control algorithm for the configuration and trajectory of the rover by changing the configuration of the Mars rover.Firstly,the coordinate system of the Mars rover is established,and the complete kinematics modeling and analysis of the rover are carried out from the aspects of the passive joint angle calculation,the wheel-ground contact angle calculation,the turning condition of the Mars rover and so on.Secondly,the mathematical model of stability margin of the Mars rover in the surface environment of Mars is derived by combining the information of the Mars rover on-board sensors and taking the angle of the angle adjustment mechanism of the Mars rover as the variable.The interior point method is used to solve the optimal stability margin and the desired joint angle of the angle adjustment mechanism.Based on this expectation,the angle is planned to optimize the configuration of the rover,to improve the driving stability margin of the rover in the unstructured environment.Then,the energy consumption function of the rover on the surface of Mars is derived by considering the factors of the rover overcoming its own gravity work and the internal loss of the single joint controller,and the minimum value is solved and construct the energy consumption weight map.Based on the constructed energy weight map,the path with the least energy consumption is calculated by using the Dijkstra.Finally,based on the Adams dynamics model of Mars rover,Matlab is used to build the motion control system and carry out joint simulation analysis to verify the effectiveness of the algorithm proposed in this paper.The result shows that:1.The kinematic model can accurately describe the motion relationship of the Mars rover.2.By using the stability margin optimization control algorithm,the stability margin of the rover under the condition of one side wheel obstacle crossing can be increased by 42.96%,and the stability margin of the rover under the condition of climbing condition can be improved by 34.07%.By using this optimal control algorithm,the rover can avoid overturning and successfully complete the condition of one side wheel obstacle crossing on the slope.3.The energy utilization efficiency of the rover can be greatly improved by using the path planning algorithm based on energy constraints.