Most active vibration suppression approaches have attempted to suppress structural vibration by incorporating active material actuators, such as piezoceramic, within the structure to act directly against vibratory loads. These approaches require the piezoceramic actuators to generate significant force and deflection simultaneously to effectively suppress vibration. Unfortunately, successful implementation of these approaches has been hindered by the limited displacement capabilities of piezoceramic actuators. The Smart Spring concept is an unique approach to actively control combinations of dynamic impedance characteristics of a structure, such as the stiffness, damping, and effective mass to suppress vibration in an indirect manner. The piezoceramic actuators employed in the Smart Spring concept are not used to directly counteract excitation loads but rather adaptively vary the effective impedance properties of the structure. Therefore, the piezoceramic actuators in the Smart Spring are not required to produce large forces and deflections simultaneously. This paper demonstrates the ability of the Smart Spring concept to control dynamic impedance characteristics of a structure through numerical simulations and experimental investigations. Mechanical shaker tests using the proof-of-concept hardware verified the controllability of the impedance properties using the Smart Spring device and its ability to suppress vibration. More importantly, the tests conducted in a wind tunnel demonstrated the performance of the Smart Spring under highly varying unsteady excitation conditions. These tests confirmed that the Smart Spring system is able to actively suppress vibration through adaptive control of structural impedance properties.

Additional Metadata
Keywords Active vibration control, Adaptive controller, Impedance control, Piezoceramic actuators, Smart Spring
Persistent URL dx.doi.org/10.1117/12.539878
Conference Smart Structures and Materials 2004 - Smart Structures and Integrated Systems
Citation
Wickramasinghe, V. (Viresh), Yong, C. (Chen), Zimcik, D. (David), Harold, T. (Tim), & Nitzsche, F. (2004). Smart spring: A novel adaptive impedance control approach for active vibration suppression applications. In Proceedings of SPIE - The International Society for Optical Engineering (pp. 359–369). doi:10.1117/12.539878