Actuator fault detection by nonlinear sliding mode observers: Application to an actuated seat

This paper deals with actuator faults detection and isolation using nonlinear sliding mode observers for an actuated seat. The goal is to ensure the comfort and the security of the users in simulators applications. The principle is to reconstruct the state vector and measurements of the system by sliding mode observers and compare the estimated outputs with those measured. In this work, a multi-observers technique is used. It consists on construction of many observers such that each observer must be robust to noises and to other uncertainties but sensitive to one actuator fault. Residuals are the estimation errors which are the differences between measurements and their estimations. Without failure in the actuator, the residual remains around zero and if a fault occurs, it deviates significantly from zero. Simulation results are given at the end to show the effectiveness of the approach.