Vibration Control of Structures With Closely Spaced Frequencies by a Single Actuator

Abstract

A variable gain direct velocity feedback is proposed to control vibrations in structures with two closely spaced natural frequencies using a single actuator. First, limitation of the conventional constant gain velocity feedback is discussed based on perturbation analysis of the free response of structures with two vibration modes and a single actuator. Then, a variable gain feedback is constructed from the physical intuitions obtained from these solutions. The variable feedback gain is derived in terms of the state of the system while the feedback loop remains direct velocity feedback. Numerical studies confirm the efficiency of the proposed method.