基于视觉测量的光纤定位闭环控制方法  

Optical Fiber Positioning Closed-Loop Control Method Based on Visual Measurement

作　　者：曹建 刘志刚[1] CAO Jian;LIU Zhi-gang(School of Engineering Scienco,University of Scienco and Technology of China,Hefe-230027,China)

机构地区：[1]中国科学技术大学工程科学学院,安徽合肥230027

出　　处：《测控技术》2021年第7期94-99,共6页Measurement & Control Technology

基　　金：中国科学技术大学先进天文仪器技术研究(KY2090000053)。

摘　　要：目前大天区面积多目标光纤光谱天文望远镜(Large Sky Area Multi-Object Fiber Spectroscopy Telescope, LAMOST)光纤定位采用开环控制模式,光纤定位精度完全取决于预先定标的准确性,预先定标误差长期影响光纤定位精度且定标过程繁杂。提出一种基于视觉测量的光纤定位闭环控制,通过引入摄影系统,采取固定光纤约束下光斑中心位置视觉检测方法,实时确定光纤空间位置,自动控制光纤单元逼近目标点,既保证了光纤定位的精度,又免去了繁杂的预先定标过程。LAMOST现场实验数据表明,提出的视觉检测方法将光纤位置检测的稳定性从50μm提高至10μm,闭环控制方法下的90%光纤单元定位误差小于40μm,满足光纤高精度定位要求。At present,the optical fiber positioning of large sky area multi-object fiber spectroscopy telescope(LAMOST)adopts an open-loop control mode.The optical fiber positioning accuracy depends entirely on the accuracy of pre-calibration,and the pre-calibration error limits the fiber positioning accuracy for a long time and the calibration process is complicated.A alosed-loop control of fiber positioning based on vision measurement is proposed.By introducing a camera system,a visual detection method for the spot center position under fixed fiber constraint is adopted to determine the fiber spatial position in real-time,and automatically control the fiber unit to approach the target point,ensuring the high precision of the fiber for a long time.Moreover,the efficiency of pre-calibration is greatly improved.LAMOST field experimental results show that the proposed visual detection method improves the stability of fiber position detection from 50μm to 10μm,and the 90%fiber unit positioning error under the closed-loop control method is less than 40μm,which meets the requirements of high-precision fiber positioning.

关 键 词：LAMOST 闭环控制 稳定性 参考光纤 

分 类 号：TP311[自动化与计算机技术—计算机软件与理论] TH751[自动化与计算机技术—计算机科学与技术]