基于惯性冲击原理的非对称夹持式压电旋转驱动器的实验研究

针对目前压电驱动器主要使用锯齿波这种非对称波电信号驱动压电晶体实现驱动的现状，设计了非对称夹持构件，提出了非对称夹持压电双晶片振子的旋转驱动器的结构设计方案，使对称波电信号作用在压电双晶片振子上，产生正反两方向大小不同的周期性惯性冲击力，驱动机构实现旋转位移。建立了压电旋转驱动器的动力学模型，并分析了非对称夹持旋转驱动器实现大小不同的惯性冲击力原理以及压电旋转驱动器的运动过程。组成了压电旋转驱动器的测试系统，在不同电压幅值、频率的方波激励下，对压电旋转驱动器的平均步长进行了测试。结果表明：非对称夹持式压电旋转驱动器能实现较稳定的单向转动，最大行程360°，最大承载能力超过300g，步长分辨率5µrad，最大转动速度4000µrad/s；驱动器样机在20V、2Hz的方波激励下，平均运动步长12µrad，转动速度24µrad/s。

EXPERIMENTAL RESEARCH ON ASYMMETRICAL ROTATED PIEZOELECTRIC ACTUATOR BASED ON THE PRINCIPLE OF INERTIAL IMPACT

The asymmetrical rotated piezoelectric actuator is mainly driven by sawtooth wave- a kind of asymmetrical wave. Focused on the disability of symmetrical wave drive, a new kind of asymmetrical gripper mechanism is designed, which is used to fix the piezoelectric cantilever bimorphs. Based on the principle of the converse piezoelectric effect, using symmetrical wave to drive the piezoelectric cantilever bimorphs is proposed. The piezoelectric cantilever bimorphs get inertial impact force on which symmetrical wave acts, by which the rotated actuator is driven. The dynamic model of the rotated actuator is constructed, whose movement principle is analyzed, too. Experiment testing system is built and the rotated actuator’s velocity characteristics under different frequencies and voltages are tested. The results show that the asymmetrical rotated piezoelectric actuator realizes stable and forward direction movement. When the voltage is 20V and the frequency is 2Hz square wave, its average step is up to 12μrad and the rotation velocity is up to 24μrad/s. The rotated actuator’s maximum stroke is 360°, carrying capacity reaches to 300g, resolving capability is 5µrad, and rotation velocity achieves 4000µrad/s.