Adaptive finite‐time fault‐tolerant control for flexible‐joint robotic stochastic systems with input saturation and sensor fault

Summary A new fault‐tolerant approach to input saturation and sensor faults is presented for flexible‐joint robotic stochastic nonlinear systems with finite‐time convergence performance. More precisely, a new command filter is designed and embedded into the backstepping framework, which greatly reduces the amount of calculation. By using the estimation ability of fuzzy logic system and less adjustable parameters, the problems of sensor faults and unknown functions are solved, which facilitates the design of controllers. A smooth function and mean‐value theorem are used to deal with the difficulty associated with system signals. A novel simpler controller is developed to ensure that the trajectory tracking error converges to a sufficiently small neighborhood around the origin within finite time, while there are random noises. Finally, the effectiveness of the presented scheme is verified by simulation results.