Sliding mode trajectory tracking control for uncertain manipulators based on fully actuated system theory

This paper addresses the trajectory tracking control problem for uncertain robotic manipulators within the framework of fully actuated system (FAS) theory. By synergistically combining FAS theory with sliding mode control techniques, a novel control strategy is developed to ensure high-precision trajectory tracking of multi-joint manipulators subject to both model uncertainties and external disturbances. The control design begins with a comprehensive modeling of the manipulator dynamics, explicitly accounting for inherent uncertainties and external perturbations. To mitigate the impact of these uncertainties, a nonlinear disturbance observer is employed, providing effective compensation for the aggregated disturbances affecting the system. The original trajectory tracking model is then reformulated as a second-order fully actuated system. Leveraging this reformulation, a sliding mode controller is designed in tandem with the disturbance observer to guarantee robust and accurate trajectory tracking. The efficacy and robustness of the proposed control scheme are validated through detailed simulation studies.