A dynamic scaling approach to adaptive fault-tolerant control for nonlinear systems via output feedback

For a class of uncertain nonlinear systems with actuator failure, a dynamic-scaling output feedback control approach is proposed to address the adaptive practical tracking problem. Compared with existing nonlinear fault-tolerant control methods, a pair of new adaptive observer and control law are developed and the main innovations lie in: (i) novel time-varying coupled matrix inequalities are introduced to deal with the actuator failure; (ii) a non-identification adaptive gain is used to compensate the actuator failure, unknown control coefficients and nonlinear parameters in nonlinearities; (iii) our control approach is non-backstepping, which achieves the global output feedback control of nonlinear systems beyond the classic output-feedback form.