Experimental Verification of Optimal Actuator Location and Configuration Based on Actuator Power Factor

Abstract

The actuator power factor is defined as the ratio of the total dissipative mechanical power of a PZT actuator to the total supplied electrical power to the PZT actuator. If measured experimentally, it can be used to optimize the actuator location and configuration for complex structures. The concept of actuator power factor is based on the ability of an integrated induced strain actuator such as a PZT to transfer supplied electrical energy into structural mechanical energy. For a given structure such as a beam or a plate, the location and configuration of an actuator will directly influence the authority of the actuator towards driving the structure. Presented in this paper are the experimental as well as the theoretical results for the case of a cantilever beam as a proof-of-concept of this technique. The design of a fixture which allows for the relocation of a PZT patch which can be used for both actuation and sensing is presented as well. For the experimental case, the electromechanical PZT admittance was measured by an HP 4194A impedance analyzer for the power factor analysis. The experimental and the theoretical power factor results were subsequently compared and showed good qualitative similarities over the frequency range analyzed. This initial comparison between the experimental and the theoretical power factor results will be used to analyze the capabilities and limitations of the actuator power factor algorithm as a tool for determining the optimal configuration and location for a PZT actuator for simple as well as complex structural vibration control applications.