Position and attitude closed loop control of wheel-legged all terrain mobile robot

When the wheel-legged robot is in the state of obstacle crossing, it is inevitable to change the attitude and position (centroid position and pitch and roll attitude). In order to control its position and attitude, the multi-link suspension system of automobile is adopted to design a new wheel-legged robot to ensure the stability in complex environment. Firstly, the single leg kinematics model of the wheel-legged robot is established, and a single leg test bench is built to verify the correctness of the model. Then, the pitching and rolling model is established for the position and attitude of the wheel-legged robot, and the position and attitude of the wheel-legged robot are decoupled. the closed-loop control of the robot is realized in the condition that the position components of the center (x, y, z) of the wheel-legged robot are constants. Then, the proportional control (P-control) is used to build the control strategy of the wheel-legged robot in Simulink. Finally, the virtual prototype of the wheel-legged robot is created in Adams, and the PAC tire model is built for the large outer angle, and the joint simulation model of Simulink and Adams is used to confirm the effectiveness of the control strategy on the three-dimensional slope. Simulation results show that the centroid position and attitude of the wheel-legged robot have good tracking effect, and the position error and attitude error are controlled within 4.3% and 5% respectively, so the effectiveness of the control strategy of the wheel-legged robot is verified. © 2019, Jilin University Press. All right reserved.