Robust adaptive diagnostic observers design for actuator fault dynamic systems

The problem of the adaptive observer design for the diagnosis of actuator faults in deterministic systems is addressed. A general situation where the system is subjected to either model uncertainty or external disturbance is considered. The fault is diagnosed by an adaptive diagnostic observer, respectively. A new design algorithm to the adaptive diagnostic observer is proposed and the respective observer gains are obtained through the solution of a Riccati equation with linear constraints. A systematic algorithm for obtaining adaptive diagnostic observers which guarantee the resulting output error and parameter estimation error converge exponentially is provided.