Fault-tolerant control scheme for manipulator with actuator and sensor failure

The fault control for manipulator with actuator and sensor faults is investigated. For actuator fault, a fault observer is designed based on multivariable second order sliding mode to estimate this fault information in finite time. Then, the estimated values are incorporated into continuous controller to compensate the real actuator fault. In presence of both actuator and position (or velocity) sensor faults, the failure sensor is discarded and a state observer is designed using second order sliding mode to estimate the position (or velocity) information in finite time. Meanwhile, the actuator fault is reconstructed through equivalent control method when the sliding mode motion is achieved. The effectiveness of the proposed fault control scheme is verified in simulation.