A novel approach to active vibration isolation with electrohydraulic actuators

This paper presents a novel reformulation of the standard active vibration control problem for large systems to take advantage of the natural dynamics of a particular type of actuator: the electrohydraulic actuator. The standard linear vibration control problem set-up is followed by details of the limitations to this standard approach for electrohydraulic systems. This root of the problems lies in the attempt to utilize the electrohydraulic actuation system to provide a particular force. Previous work (Alleyne & Liu, 1999) has shown the inherent limitations to force tracking for these systems. To circumvent the limitations, the problem is reformulated as a velocity tracking one, which lends itself naturally to the dynamics of electrohydraulic systems. Subsequently, a SISO controller can be readily designed for the velocity tracking problem using standard controller design tools. Although the controller design is relatively standard, experimental results are given which demonstrate the efficacy of the problem reformulation.