Residual Generation for Small Commercial Aircraft Fault Diagnosis

This paper addresses the problem of the diagnosis of the input sensor faults on a general aviation aircraft, characterised by a non-linear model, in the presence of wind gust disturbance and measurement errors. In particular, this work investigates the design of residual generators in order to realise complete diagnosis schemes when additive faults are present. The use of an input-output description for the linearised model of the aircraft allows to compute in a straightforward way the residual generators for fault diagnosis. These tools lead to dynamic filters that can achieve both good disturbance signal de-coupling and robustness properties with respect to both linearisation error and measurement noise. Mathematical descriptions of the aircraft measurement sensors are also taken into account. The results obtained in the simulation of the faulty behaviour of a PIPER PA30 aircraft are finally reported.