一种微位移促动器的设计和检测

Design and test of a micro -displacement actuator

设计制造了一套微位移促动器并进行了检测。比较了常用的实现高精度、大行程的微位移机构的工程方法,并结合大天区面积多目标光纤光谱天文望远镜(LAMOST)微位移调节机构的实现原理,采用步进电机驱动减速器、精密丝杆型式,及高精度的杠杆缩放结构,实现了高精度、大行程的微位移促动器。根据该传动机构的特点,对机构的误差进行了分析,通过计算机查表校正丝杆的传动误差。双频激光干涉仪的检测结果表明该微位移促动器在行程范围内灵敏度达到了201nm±48nm,步长为10μm,单向精度达到了标准偏差237nm。

A set of micro-displacement actuator was developed and tested for the large area multi-object fiber spectroscopic telescope (LAMOST). Conventional techniques for micro-displacement mechanism with high accuracy and long travel in engineering applications are studied. In view of implementation principle of the active-motion mechanism in the LAMOST, integrated with precision lever, a scheme of stepper motor, harmonic reducer and ball screw, the goal of both high accuracy and long travel is realized. The origins of error are investigated, before a computer look-up table is designed to calibrate transmission error and to improve absolute accuracy of the actuator. Measured with laser interferometer in laboratory, the actuator confirms itself that it can be used as micro-displacement actuator of the LAMOST, thanks to its resolution of 201 nm ± 48 nm and unidirectional accuracy of 237 nm (standard deviation) at a step of 10 μm.