Hierarchical Tracking Control for a Composite Mobile Robot Considering System Uncertainties

Composite mobile robots (CMRs) have gained extensive application in the industrial sector due to their integrated loading and operational capabilities. The trajectory tracking control module, being a vital constituent, directly influences the degree of stability in robot operations. However, current tracking control methods exhibit suboptimal performance when encountering system uncertainties arising from both the environment and inherent system factors. This paper presents a novel hierarchical control strategy tailored for the hierarchical model of composite mobile robot chassis. This strategy effectively combines velocity control and torque control, resulting in satisfactory trajectory tracking control. Firstly, a hierarchical kinematic and dynamic model is constructed to account for varying payload and environmental uncertainties. Subsequently, a pose-velocity-torque hierarchical controller is formulated to regulate chassis speed by manipulating torque input, thereby achieving pose regulation and trajectory tracking. Finally, the control algorithm is implemented using MATLAB and adapted to industrial computers for the development and validation of the controller's effectiveness. Comparative experiments are conducted against existing methods, demonstrating the superiority of the proposed controller.