Issues of fault diagnosis and fault tolerant control for aerospace systems

In this chapter two novel nonlinear aircraft and satellite active fault-tolerant control system strategy have been proposed. In particular, the applied AFTC is based on a FDD module providing a fault estimate exploited by an additional feedback loop, thus allowing fault accommodation. In this way, the controller can be designed on the faulty-free model. It is worth observing that the fault estimates are robust (thanks to NLGA) to aerodynamic disturbance and/or other faults. With reference to the design of the control systems, it is important to point out that the built–in controller can be exploited. Morever, in case of aircraft, a novel controller has been designed on the basis of singular perturbation of the aircraft dynamic. The exploited high fidelity aircraft and satellite model and the assumed practical mathematical hypotheses were tested via extensive simulations. The results showed that the designed nonlinear active fault-tolerant scheme was reliable and ready for implementation