Actuator fault detection and isolation for robot manipulator using higher order sliding mode observers

Fault detection and isolation (FDI) method for actuator faults for robot manipulator by applying a model-based FDI fault, which may happen on a specifific component of the system. To detect and isolate actuator faults, higher order sliding mode Unknown Input Observers (UIO) are proposed to make analytical redundancy. The observers input laws are designed according to the so-called Super-Twisting Second Order Sliding Mode Control (SOSMC) technique and they are proved to be able to guarantee the exponential convergence of the fault estimate to the actual fault signal. The simulation results show the effectiveness and robustness for the proposed approach.