A Fault-tolerant Synchronous Sliding Mode Control for a 4-DOF Parallel Manipulator With Uncertainties and Actuator Faults

This paper proposes a novel fault-tolerant synchronous sliding mode control for a 4-DOF parallel manipulator against uncertainties such as modelling error and actuator faults. The proposed control is developed with the consensus approach, sliding mode control, and extended state observer to manage the tracking objective and guarantee the synchronous requirements. The consensus approach combines the tracking and synchronous errors, which helps to integrate both the tracking and synchronous requirements into cross-coupling errors. Firstly, the kinematics and dynamics of the parallel manipulator are described according to the geometric and Euler Lagrange approaches with the challenges. Secondly, the Lyapunov approach is implemented to verify the stability and robustness of the proposed control in theory. Then, some simulations are conducted in MATLAB Simulink with the robotic dynamics generated by converting the design model in SOLIDWORKs into SIMSCAPE. The comparisons between the proposed control and other controllers are made by creating simulations to evaluate the advantages of the proposed approach.