Vibration Control of Flexible Systems Via Sliding Manifold Approach

In this paper an active vibration controller for exible systems is developed using a sliding manifold approach. The controller is designed to eliminate the system's mode whose frequency is close to the disturbance frequency. The sliding approach ensures the robustness of the control scheme against the large uncertainties generally present in flexible structure models The sliding surface consists of a time-invarying part which eliminates the selected mo de without affecting the other dynamics and a timevarying part which bounds the control amplitude and its rate in the transient. If the state is not available an observer is needed to implement the control law In particular a time varying term is introduced in the observer in order to avoid the peaking phenomenon The features of the controller and observer allows one to reduce the excitation of the high frequencies mo des hence to reduce the spillover phenomenon.