三自由度行波型超声波电机的静力学分析

从三自由度行波型超声波电机的驱动原理与基本结构出发，使用变换矩阵得到了定转子的位置变换关系，进而分析了球转子的受力情况，并给出了定转子接触圆周的接触力方程.根据球转子和各个行波定子的力平衡方程，得到了球转子球心的微位移和行波定子的轴向压紧量与行波定子的轴向压紧力的关系方程.仿真分析表明，对电机定子施加对称的压紧力、增大定子轴线与基本坐标系轴线的夹角和减小定子半径，能够减小定转子接触圆周上定子与转子不相互接触的区域，使电机性能得到充分发挥.

Statics analysis of three-degree-of-freedom traveling-wave type ultrasonic motor

The driving principle and basic structure of three-degree-of-freedom spherical traveling-wave type ultrasonic motor were introduced, and the coordinate transformation model and the position relation of rotor and stators were set up. Then the stress and the contact force of rotor and stators on the contact circle were analyzed. Based on the force balance equation of the stators and rotor, the relationships of the micro displacement of the center of rotor and the axial compaction with the preload force of stators were presented. Simulation shows that applying balance force on the contact area of stators and rotor, increasing the angle between stator axis and basic coordinate system and decreasing the stator radius will decrease the uncontact region between stators and rotor and get better performance of rotor.