Prescribed performance adaptive fault-tolerant control for a manipulator

This paper investigates an adaptive fault-tolerant control for a manipulator against actuator failures. In practice, when manipulators operate for a long-time, the components in actuators are aging, which commonly cause loss of actuation effectiveness and lock-in-place. The main objective of the proposed control is to maintain system performance and stability under the existence of faults. In order to guarantee the satisfaction of the output responses with the predefined boundary, a transformation technique is used to design the proposed control. An extended state observer is applied to approximate the lumped disturbance. Additionally, an adaptive fuzzy logic system is proposed to compensate for the approximation error in the transient state. Finally, the proposed control is implemented on a 2-DOF manipulator by MATLAB Simulink. Its results demonstrated the advantages of the proposed control.