Speed Tracking Control of Caster-type Omnidirectional Mobile Platform with Variable Load

For the motion control problem of an omnidirectional platform (hereinafter referred to as platform) with three single-motor-driven caster wheels, the inverse kinematics and dynamics models of the platform were established, and a virtual prototype of the platform was built based on a series of software, including SolidWorks and ADAMS. Based on the fuzzy control principle, a speed controller was designed and the stability of the controller was proved with Lyapunov function. The Matlab/Simulink-ADAMS co-simulation method was used to simulate the movement of the platform under 0%, 20%, 50% and 100% loads. The simulation results show that the fuzzy PID speed controller can reduce the lag time of speed tracking by 56.25% on average, the maximum amplitude of rotation speed by 46.62% on average, and the trajectory error by 57% on average, which can effectively and timely suppress the influence of load changes on the platform, and make the actual speed of the platform converge to the reference speed quickly, stably and accurately. The system has strong robustness.