Adaptively disturbance attenuation design of robustly stable control system

A direct adaptive control scheme for robustly stable control systems is proposed. The adaptive controller feeds back a disturbance estimate via a filter, which includes free parameters of the robust stabilizing controller. The proposed scheme extends fixed robust stabilizing controllers, in that the free parameters can be adjusted adaptively. Since the disturbance is estimated in an online manner, it can be attenuated without using a priori knowledge about the disturbance or its generator. The effectiveness of the proposed control system design is confirmed by numerical simulations