Accession Number : ADA311647

Title :   Electro-Mechanical Modeling of the Dynamics of Active Control Systems Based on an Impedance Approach.

Descriptive Note : Final technical rept.,

Corporate Author : VIRGINIA POLYTECHNIC INST AND STATE UNIV BLACKSBURG CENTER FOR INTELLIGENT MA TERIAL SYSTEMS AND STRUCTURES

Personal Author(s) : Lalande, Frederic ; Rogers, Craig A.

PDF Url : ADA311647

Report Date : MAR 1996

Pagination or Media Count : 111

Abstract : In this fundamental research program, the focus was to develop an understanding of the physics of actively controlled material systems, especially the power consumption and energy transfer mechanisms. A new impedance approach was further developed, giving particular attention to applications involving structures with impedance characteristics similar to aircraft structures. This newly developed impedance approach has an advantage over conventional approaches, such as the quasi-static and equivalent thermal force approaches, in that it includes the dynamic interaction between the structure and the actuator. A comprehensive impedance model for plate and shell structures was completed. By taking into account the dynamic interaction between the base structure and the induced strain actuator, the impedance model can accurately predict the dynamic response of the base structure. The electro-mechanical impedance model for plate structures was then extended to determine the power consumption and actuator conversion energy efficiency. This later extension of the impedance model allows the optimization of the actuator parameters based on power considerations. Also, the temperature rise and resulting thermal stresses, which can be significant at resonant frequencies, was investigated. Finally, the impedance approach was shown to be applicable to other types of actuators, namely magnetostrictive actuators and piezoelectric stack actuators.

Descriptors :   *VIBRATION ISOLATORS, *ACTUATORS, *MAGNETOSTRICTION, CONTROL SYSTEMS, PARAMETERS, DYNAMIC RESPONSE, EFFICIENCY, ENERGY TRANSFER, SHELLS(STRUCTURAL FORMS), RESONANT FREQUENCY, ELECTROMECHANICAL DEVICES, PIEZOELECTRIC MATERIALS, AIRFRAMES, ENERGY CONSUMPTION, STACKING, THERMAL STRESSES, IMPEDANCE MATCHING, MECHANICAL IMPEDANCE.

Subject Categories : Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE