Fault Tolerant Flight Control Law Design with a Model-Following Sliding Mode Controller

A sliding mode controller based on model following control is designed for the flight control system with uncertainties and perturbations. With this controller, the controlled plant can track the reference model precisely. It is shown that this scheme provides better performance for the flight control system and the fault tolerant control objective is achieved. The proposed scheme has the advantages of the model following and sliding-mode control. A Proportional-Integral type sliding surface is designed through pole placement method to make the sliding mode have good dynamic characteristics and to eliminate the steady state error. The simple saturation control is adopted to weaken the chattering phenomena. The simulation results show that the flight control system using this controller not only doesn't require the procedure of fault detection and isolation, but also achieves the model following.