基于双目视觉技术的FAST舱索系统模型振动测量方法  

Measuring FAST cabin- cable system model's vibrations using binocular camera's technology

作　　者：崔希民[1] 王强[1] 李辉[2] 范生宏[3] 郑珂[1] 亓晓彤 

机构地区：[1]中国矿业大学(北京)地球科学与测绘工程学院,北京100083 [2]中国科学院国家天文台,北京100012 [3]清华大学土木工程系,北京100084

出　　处：《科技导报》2016年第18期270-274,共5页Science & Technology Review

基　　金：国家自然科学基金面上项目(51474217)

摘　　要：FAST望远镜舱索系统位置、振动频率的动态检测是实现闭环控制的基础。针对传统测量方法用于FAST望远镜舱索系统缩比模型振动频率检测时操作复杂、干扰性大和不易实现的缺点,根据被测物体连续振动变化的特点,提出双目视觉高速动态测频方法。该方法通过计算被测物点位三维坐标,利用快速傅立叶变换对离散的实时点位信息进行频谱变换,分析确定被测物的振动频率。实验显示,双目视觉高速动态测频方法在频率分辨率为0.04 Hz的情况下,重复测量、分时段测量的误差分别小于0.08 Hz和0.04 Hz,表明对于舱索系统之类的低频振动物体,该方法能有效满足振动频率的动态测量要求。It is the foundation to realize closed loop control that the FAST telescope feed cabin-cable＇s location and vibration frequency are dynamically measured. Due to the fact that traditional measurement methods for FAST telescope cabin-cable scaled model＇s vibration frequency measuring are of complicated operation, large disturbance, and difficult to realize, a high-speed dynamic frequency-measuring method based on binocular camera is put forward to cope with the characteristics of continuous changes in the vibrating object to be measured, It calculates object＇s three-dimensional coordinates, and uses fast Fourier transform to obtain the spectrum of real-time discrete point locations. Then the vibration frequency is analyzed. Experiments show that in the case of frequency＇s resolution being 0.04 Hz, the repeated measurement and time-segmented measuring errors of binocular camera high-speed dynamic frequency measuring are not greater than 0.08 Hz and 0.04 Hz, respectively, indicating that for low frequency vibrating objects like the feed cabin cable, this method can effectively satisfy the requirement of dynamic frequency measuring.

关 键 词：FAST舱索系统 振动频率 双目视觉高速动态测频方法 快速傅立叶变换 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]