PERFORMANCE ANALYSIS OF CONTINUOUS LINEAR MOTION OF SINGLE AND SERIES CONNECTED PIEZOELECTRIC ELEMENTS BY USING METHOD OF IMPACT DRIVE MECHANISM

Abstract

IDMcan be defined as thetransformation ofsmall vibrations of a piezo element into continuous linear motion on a frictional surface by controlling the extension and contraction speed thus the impact force.In most of previous studies, longitudinal vibrations of piezo elements are employed as in [1], [2], [3] to obtain a continuous linear motion. In this study, linear continuous motion characteristics of series connected piezoelectric (PZT) crystals are investigated both numerically and experimentally, when the method of the impact drive mechanism applied was driven by coupled transverse and torsional vibrations. For the experiments, PZT rectangular crystal bars are series connected with a neodymium magnet glued to the bottom end, and then positioned to a grinded smooth steel surface. The three test specimens were series connected one, two, and three-elements PZT-5X military grade single crystals, and the neodymium magnets were N38 grade coated with nickel. Before starting the tests, resonant frequencies of test specimens are calculated numerically by making harmonic analysis employing a finite element software (ANSYS) and tested experimentally by using the sweep characteristics of the signal generator. Triangular,and sine signal waves at resonance frequencies are applied for each test specimen at 220 Volts. Both the numerical and experimental results showed that the top-end deflection, strain energy, the impact force thus the linear velocity increases by increasing the number of PZT crystal elements of a test specimen. The research conducted herecould be supportive when designing nano/micro-scale positioning actuators anddriving systems for different kinds of high technology applications.