Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China.
School of Mechanical and Aerospace Engineering, Jilin University, Changchun 130025, China.
Rev Sci Instrum. 2023 Feb 1;94(2):025001. doi: 10.1063/5.0114030.
Multi-degree of freedom piezoelectric actuators are strongly needed for industrial applications, especially when manipulating a large and heavy mirror or lens in an optical system. A novel three-degree-of-freedom piezoelectric actuator, which is driven by two pairs of piezo-stack actuator with spatial compliant mechanisms designed to guide the motion and preload the piezo-stack actuators, is herein proposed. The structure and working principle of the proposed actuator are illustrated and its kinematic characteristic is analyzed. The stiffness of the spatial compliant mechanisms is modeled, and the dynamic characteristics are analyzed, Finite Element method is utilized to validate the correctness of the stiffness modeling and the free vibration analysis of the proposed actuator. A prototype actuator is fabricated and its output performances have been tested. Working space of X ranging from -7.1 to 5.6 μm, Y ranging from -6.2 to 8.2 μm and Z ranging from -2.3 to 2.1 μm, displacement resolutions of 15/16/21 nm along X-/Y-/Z-axis and average velocities of 52.3, 82.8 and 29.5 µm/s along X-axis, Y-axis, and Z-axis with carrying load up to 2 kg and driving frequency of 500 Hz have been achieved by the prototype actuator. The method of waveform generating for the proposed actuator has been developed with the inverse hysteresis compensation, and test results indicate that the positioning accuracy of the prototype actuator in the open loop has been improved from 0.94 to 0.23 μm for a circular trajectory tracking, from 0.48 to 0.29 μmm for an elliptical trajectory tracking, and from 0.61 to 0.32 μm for a rectangular trajectory tracking with the compensated waveform of driving voltage.
多自由度压电致动器在工业应用中是非常需要的，特别是在光学系统中操纵大而重的镜子或透镜时。本文提出了一种新型的三自由度压电致动器，它由两对带有空间柔顺机构的压电堆叠致动器驱动，该机构旨在引导运动并预加载压电堆叠致动器。说明了所提出的致动器的结构和工作原理，并对其运动学特性进行了分析。对空间柔顺机构的刚度进行了建模，并对其动态特性进行了分析，利用有限元法验证了刚度建模和致动器自由振动分析的正确性。制作了一个原型致动器，并对其输出性能进行了测试。X 方向的工作空间范围为-7.1 至 5.6μm，Y 方向的工作空间范围为-6.2 至 8.2μm，Z 方向的工作空间范围为-2.3 至 2.1μm，沿 X-、Y-和 Z-轴的位移分辨率分别为 15/16/21nm，沿 X 轴、Y 轴和 Z 轴的平均速度分别为 52.3、82.8 和 29.5μm/s，可承载 2kg 的负载，驱动频率为 500Hz。为该致动器开发了一种波形生成方法，采用了逆迟滞补偿，测试结果表明，在开环中，原型致动器的定位精度从圆形轨迹跟踪的 0.94μm 提高到 0.23μm，从椭圆形轨迹跟踪的 0.48μm 提高到 0.29μm，从矩形轨迹跟踪的 0.61μm 提高到 0.32μm，采用补偿后的驱动电压波形。
