Abstract:

Based on near-field acoustic levitation mechanism a novel piezoelectric actuator with spherical rotor was proposed. Special piezoelectric actuators were designed to produce the axial and radial near-field ultrasonic radiation, respectively, so that a spherical rotor can achieve controllable and stable levitation,and rotation with high speed. The proposed
noncontact actuator can be applied to high speed motor,ball bearing transmission and attitude sensor in the field of aerospace. The flexible control of suspended rotated rotor can be realized by different combination applications of two actuators radiating the axial and radial acoustic field. First the configurations and working principles of the axial/radial coupling noncontact piezoelectric actuator were  introduced.Then the acoustic field distribution resulting from the presented actuators was simulated numerically,and levitation and drive mechanism of spherical rotor was deeply investigated. Finally a prototype was manufactured, and the characteristics measurement system was built. By means of the laser displacement sensor the levitation characteristics of the proposed actuator was experimentally obtained, and the rotary speed of 691.5r/min is achieved.

Key words: near-field acoustic levitation, spherical rotor, noncontact, coupling

摘要：

提出了一种基于近场声悬浮机理的球转子压电作动器,特别设计了可分别沿轴向和径向辐射超声近场的作动器,其目的是为了实现球转子的稳定、可控悬浮和高速旋转,可将其应用到航空航天的高速电机、球轴承传动或姿态传感领域。该新型压电作动器通过轴向与径向悬浮装置的不同耦合形式来提供超声悬浮力并以非接触的方式驱动球转子,实现对球转子的灵活控制。介绍了轴/径向耦合式非接触型压电作动器的结构和工作原理,通过仿真得到了悬浮装置的声场分布形式,深入分析和阐释了球转子的悬浮和驱动机制,加工了样机,搭建了轴/径向耦合式超声悬浮型压电作动器的特性测试系统,通过非接触式激光位移传感器得到了球转子的悬浮特性,并获得了691.5r/min的转速。

关键词: 近场声悬浮, 球转子, 非接触, 耦合