Modeling and characterization of a linear piezomotor

This paper presents the modeling and characterization of a novel class of piezoelectric linear motors. The motor relies in its operation on a set of piezoelectric bimorphs which are sequentially activated to linearly move a drive rod along spring loaded rollers. Emphasis in this paper is placed on studying the dynamic behavior of this class of piezoelectric motors, both theoretically and experimentally, in an effort to predict the piezomotor response to various loads and excitation schemes. To this end, a numerical model has been developed to simulate the dynamics of the piezoelectric bimorphs comprising the piezomotor. Friction between the bimorph elements and the drive rod are handled using an appropriate friction model. Experimental testing of the motor is carried out to validate the predictions of the theoretical model. This effort aims ultimately at demonstrating the feasibility of employing this class of piezoelectric actuators in driving smart snake robots in order to use them as a simple and reliable mobility platform.