Motion Control Strategy of Wheel-Legged Compound Unmanned Vehicle

This paper proposes a motion control strategy for the wheel-legged compound unmanned vehicle, including attitude control and driving control. Firstly, based on tire mechanics, Lagrangian method and D’Alembert’s principle, the dynamic modeling of the driving system, wheel-legged system and vehicle body is carried out respectively. On this basis, a layered parallel control architecture is proposed. The upper-level controller consists of a driving system controller and a wheel-legged system controller. The former is used to control the longitudinal, lateral and yaw motions of the vehicle based on the model predictive control method, and the latter is used to adjust the longitudinal, pitch and roll motions of the vehicle based on PD control. The lower-level controller is used to control the output torque of the vehicle motor based on the PI control method. Finally, three typical working conditions are designed to verify the attitude control and driving control of the vehicle. The simulation results show the accuracy and stability of the designed controller to track the target command.