一种新型力矩促动器的设计研究

In order to reduce expensive cost on mirror polishing and opto-mechanical assembly and correct the low-order aberrations caused by thermal and gravity deformation, so called “Warping Harness” has been used to apply moment to the pivot of whiffletree to achieve real-time correction of the mirror surface. This Warping Harness has been adopted in the Keck telescope and has been further developed in the current extremely large telescope. Based on the research of the above-mentioned mechanism, this project aims to implement design and prototype test of a new type of Warping Harness. It will lay the relevant technical foundation for the construction of large-aperture optic telescopes in China.

为了降低较为昂贵的镜面抛光和光机装配费用，以及应对温度、重力及其他意外因素导致的镜面低阶像差，一种在被动的浮动支撑结构上施加力矩以实现面型实时校正的力矩促动器在凯克望远镜上已有初步的应用，并在当前的三十米级望远镜中得到进一步发展，本项目旨在对上述机构完成调研的基础上，提出一种新形式的力矩促动器实现方案，为我国大口径望远镜建设奠定相关技术基础。

为了降低较为昂贵的镜面抛光和光机装配费用，以及应对温度、重力及其他意外因素导致的镜面低阶像差，提出了一种新形式的力矩促动器实现方案。本项目首先对拼接子镜支撑系统进行集成建模，优化设计力矩促动器的布局，提出18个力矩促动器布局方案，在满足光学设计需求的同时，有效节约了建设经费并降低了工艺的复杂性；其次搭建实验平台，利用力传感器对叶片弹簧的应变片进行标定，同时对整套力矩促动器的性能进行了测试，其线性度、重复性精度符合设计要求；最后基于PI模型对力矩促动器的迟滞非线性误差进行校正补偿，力矩促动器输出力误差的RMS从1.888N降低到0.2596N，保证了系统的控制精度，为我国大口径望远镜建设奠定相关技术基础。