DYNAMIC SIMULATION OF TRAVELLING WAVE ULTRASONIC MOTORS FOR AEROSPACE APPLICATION

摘要

In this paper a dynamic simulation of a new model for a Travelling Wave Ultrasonic Motor for antennas' reflectors positioning, developed by Alenia Spazio S.p.A. (Roma, Italy) within an Italian Space Agency (ASI) development Program, is described. The dynamic equations for the stator and the rotors of the ultrasonic motor are assumed into a differential system, whose equations are coupled by terms which represent interface generalized forces. Neglecting transient conditions, the complete mathematic model of the system is solved and an iterative process is developed, in order to obtain the motor's running curves for different operation parameters, geometric dimensions and physical features of the system. The algorithm is implemented in Matlab ® environment and a Graphical User Interface is constructed for user-friendly managing. This model represents a simple and powerful aid to determine final motor design that can satisfy specifications or to predict motor's behaviour under different working conditions, as orbital ones.