Optimal Feedback-Adaptive Feedforward Controller for Vibration Suppression of a Cantilever Beam Using Piezo-Actuators

摘要

In this paper the combined optimal feedback-adaptive feedforward controller proposed to attain better performance of active vibration suppression of flexible structures subjected to different type of disturbances. The structure considered here is a cantilever beam actuated with a PZT patch actuator. The proposed controller consists of two individual parts, a filtered-x controller as a feedforward part and an optimal linear controller as a feedback part. Recursive Least Square algorithm (RLS) is used for the adaptive filtering scheme in Filtered-x adaptive feedforward controller. LQG optimal controller is also used in the feedback part of the controller. This research investigates the effectiveness of the proposed controller in comparison with other types of applied controllers. In this regard, the simulation study is performed on a finite element model to evaluate the performance of the proposed controller under different disturbances. It has been shown that this method can reduce the vibration caused by random disturbances due to its broad-band disturbance rejecting performance. Also, it can fully suppress the vibration caused by a harmonic disturbance in a small decay time because of its narrowband disturbance rejecting performance with the fast parameter adaptation algorithm (RLS).