Active Fault-Tolerant Control Design for Actuator Fault Mitigation in Robotic Manipulators

This paper proposes an active fault-tolerant control (FTC) scheme for robotic manipulators subject to actuator faults. Its main objective is to mitigate actuator faults and maintain system performance and stability, even under faulty conditions. The proposed FTC design combines the robustness and finite time convergence of non-singular terminal synergetic control with the optimization properties of an interval type-2 fuzzy satin bowerbird algorithm. System stability is established via the Lyapunov stability criteria. An adaptive state-augmented extended Kalman filter is implemented as the fault detection and diagnosis (FDD) module, to provide the controller with necessary information about faults in real time. This FDD scheme is based on the simultaneous estimation of the faulty parameters and system states. The effectiveness of the proposed approach is assessed using a simulated two-degree-of-freedom robotic manipulator subject to various faulty scenarios.