基于超声波电机中压电陶瓷的逆压电效应、定子振动、转子旋转的原理,考虑弯曲振动引起的纵向振动,应用几何原理和振动理论,对圆柱定子激励频率相同、激励电压和激励的初相位各不相同的电信号引起的各单相振动进行合成,推导了三自由度圆柱定子超声波电机在三相同时激励时定子表面质点的轨迹运动方程,并仿真出同频率、不同相位差、不同电压激励时的运动轨迹,分析了这三个因素对定子表面质点轨迹的影响,为三自由度超声波电机的轨迹控制和姿态控制奠定了理论基础。
Based on the principles of the converse piezoelectric effect, the stator vibration and the rotor rotation, taking acount of the longitudinal vibration caused by the bending vibration, the locus of the point on the top surface of the cylindrical stator of the three-freedom ultrasonic motor has been deduced by geometric method in this paper. And different curves of the locus have been simulated in different amplitude of the excited voltage to three PZTs, different phase contrast of three natural resonant frequencies of the stator and different position of the top surface of the stator. The influence to the controlling accurate of the three-freedom ultrasonic motor has also been discussed in three conditions. The results can be the key and prerequisite of the control strategy for three-DOF ultraic motors, and the kinetic equation can be the basis of increasing conversion efficiency from stator vibration to mechanical output of the three-DOF motor, the optimized designing of cylinder stator.