为了满足大行程、高精度旋转运动的需求, 以尺蠖型累积步进角位移为原理, 设计了尺蠖型超磁致伸缩旋转驱动器。以超磁致伸缩棒为动力源、直角柔性铰链为回弹元件, 通过施加特定时序的激励信号, 使钳紧机构和驱动机构有效配合, 实现了转子的步进式角位移输出。将直角柔性铰链简化为超静定梁进行了静动态特性分析, 并建立了空间力学模型。搭建了实验测试系统, 对超磁致伸缩旋转驱动器的输出性能、钳紧稳定性和输出角位移稳定性进行了实验测试。实验结果表明: 在驱动电压为4.5 V、频率为2 Hz的条件下, 平均单步角位移为278.81 μrad, 最大误差为7.92 μrad, 最大相对误差为2.83%; 系统钳紧机构的径向跳动小于1.35 μm, 驱动器工作状态稳定可靠, 输出精度高, 可实现360°转动; 模型计算结果与实验结果基本一致, 最大误差为12.11 μrad, 最大相对误差为4.34%。

In order to meet the requirements of large-stroke and high-precision rotating motion, an inchworm giant magnetostrictive rotary actuator was designed based on the principle of inchworm cumulative stepping angular displacement. With a giant magnetostrictive rod as the power source and a right-angle flexure hinge as the springback element, the stepping angular displacement output of the rotor was realized by applying a specific excitation timing signal to make the clamping mechanism and driving mechanism cooperate effectively. The static and dynamic characteristics of rectangular flexure hinges were analyzed by simplifying them into statically indeterminate beams, and a spatial mechanical model was established. The experimental test system was built, and the output performance, clamping stability, and stability of the output angular displacement of the inchworm magnetostrictive rotary actuator were tested. The experimental results show that when the driving voltage is 4.5 V and the frequency is 2 Hz, the average one-step angular displacement is 278.81 μrad, the maximum error is 7.92 μrad, the maximum relative error is 2.83%, and the radial run-out of the clamping mechanism is less than 1.35 μm. The rotary actuator works stably and reliably with a high output precision, which can rotate 360°. The calculated results of the model are in agreement with the experimental results. The maximum error is 12.11 μrad and the maximum relative error is 4.34%.