Actuator fault reconstruction based on terminal sliding mode observer for aircraft anti-skid braking system

A method of fault reconstruction, which is based on terminal sliding mode observer, is proposed for aircraft anti-skid braking system. In the traditional sliding mode observer, the estimated error of unmeasured state is asymptotic convergence, which affects the timeliness of actuator fault reconstruction. In response to the above problem, the property of finite time convergence of terminal sliding mode is used to build a nonsingular terminal sliding mode observer (NTSMO), which ensures that all of the state estimation errors converge to zero in a finite time with the unknown actuator fault. Accordingly, a reconstruction law based on the specific equivalent control approach is then designed to accurately estimate the value of actuator fault in real-time and online. The performance of the proposed scheme is evaluated extensively through numerical simulations with MATLAB.