Active Vibration Control of Distributed Systems Using Delayed Resonator With Acceleration Feedback

The Delayed Resonator (DR) and Dual Frequency Fixed Delayed Resonator (DFFDR) are newly introduced control techniques for active vibration absorption. Both methods propose a delayed position feedback within the absorber section of the structure to impart ideal resonance features to the absorber. When installed on an oscillating primary body, they form “notch filters” at their resonance frequencies attenuating the response of the primary structure. The DR absorber is shown to be real-time tunable to time varying disturbance frequencies. In this article, a number of new issues are considered. First, the basic theory is modified for acceleration feedback instead of position, which was originally proposed for the DR methodology. Second, the new absorption methods are implemented on distributed parameter structures which are under high frequency excitation (around 1 KHz). Stability of the combined structure is studied on a reduced order multi-degree-of-freedom primary structure together with the DR absorber. Experimental tests are conducted on a steel beam to verify the analytical findings. Piezoelectric actuators are used both to generate harmonic disturbances and to implement the control. The correspondence observed between the theoretical and experimental results is encouraging. The efficiency of the DR and DFFDR absorption techniques is demonstrated.