Fault-tolerant control for second-order nonlinear systems with actuator faults via zero-sum differential game.

Stable operations of control systems play a vital role in mission accomplishments of the second-order nonlinear systems, such as six-axis robots used in intelligent production lines, industrial equipment and control systems. In this paper, a fault-tolerant control scheme is developed for a class of second-order nonlinear control system under actuator bias faults and loss of effectiveness faults via the zero-sum differential game method. Based on the backstepping method, a controller is designed to ensure system tracking performance. Then by the zero-sum differential game method, a fault-tolerant controller is designed for the equivalent error system. Simulation results show the validity of the designed fault-tolerant control scheme. • The stability of the system and the optimality of control consumption are achieved. • Both unknown bias and loss of effectiveness faults are solved. • Uncertainty of the control gain matrix caused by the fault pattern matrix is solved. [ABSTRACT FROM AUTHOR]