The goal of this paper is to describe an active decentralized fault-tolerant control (ADFTC) strategy based on dynamic output\nfeedback for reconfigurable manipulators with concurrent actuator and sensor failures. Consider each joint module of the\nreconfigurable manipulator as a subsystem, and treat the fault as the unknown input of the subsystem. Firstly, by virtue of\nlinear matrix inequality (LMI) technique, the decentralized proportional-integral observer (DPIO) is designed to estimate and\ncompensate the sensor fault online; hereafter, the compensated system model could be derived. Then, the actuator fault is estimated\nsimilarly by another DPIO using LMI as well, and the sufficient condition of the existence of H? fault-tolerant controller in the\ndynamic output feedback is presented for the compensated system model. Furthermore, the dynamic output feedback controller\nis presented based on the estimation of actuator fault to realize active fault-tolerant control. Finally, two 3-DOF reconfigurable\nmanipulators with different configurations are employed to verify the effectiveness of the proposed scheme in simulation.The main\nadvantages of the proposed scheme lie in that it can handle the concurrent faults act on the actuator and sensor on the same joint\nmodule, as well as there is no requirement of fault detection and isolation process; moreover, it is more feasible to the modularity\nof the reconfigurable manipulator.
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