基于辅助参考线的光栅投影轮廓测量系统及标定方法  

Novel Grating Projection System Based on Assistant Line and its Calibration Method

作　　者：王涛[1] 孙长库[1] 石永强[1] 王鹏[1] 

机构地区：[1]天津大学精密测试技术及仪器国家重点实验室,天津300072

出　　处：《光学学报》2011年第1期184-189,共6页Acta Optica Sinica

基　　金：新世纪优秀人才支持计划(NCET-06)资助课题

摘　　要：传统光栅投影轮廓系统需要严格的几何尺寸约束,实际使用中难以构造,而且采用参考平面作为被测物体的相位测量基准,限制了系统的测量和应用范围。针对这些问题,提出了采用辅助参考线代替传统光栅轮廓系统中参考面的系统模型,给出了利用参考线将相对相位校正为绝对相位的公式,利用空间映射及优化求解算法实现了从绝对相位到被测物真实空间坐标的映射。设计了圆线形靶标,只采用一个平面靶标即可实现靶标点空间坐标、靶标相位以及参考线位置的采集,简化了标定过程。最后进行了测量实验,使用两幅图像完成了石膏头像三维数据的获取,通过测量平面靶标的平移和旋转的间距,验证了方法的测量精度,靶标平移间距的均方差为0.02 mm,旋转间距的均方差为0.03°。实验证明该测量方法速度快,系统搭建和标定方法简易,测量精度高,具有重要的应用价值。The structure of the traditional grating projection system is difficult to construct for its rigid geometry constraints.In addition,the reference plane is inevitably employed in the system which limits the range of the measurement and the application.In order to resolve the above problems,an assistant line is introduced to the system.The equation of translation from relative phase to absolute phase is deduced according to the assistant line.Space mapping method and its optimization algorithm are employed,by which the object′s real 3D data can be calculated.A circle liner target is designed,with which the extraction of feature points,target phase and feature line can be accomplished by only one image,and the procedure of the calibration is simplified.Last,the profile of a plaster model is measured by the system with two images,and the accuracy of the result is proved,the mean-square deviation（MSE） of the distance between ten shifting planes is 0.02 mm,and the MSE of the angle between ten rotating planes is 0.03°.The experiment shows that the method is accurate,fast,and easy to construct and calibrate,which has improtant application values.

关 键 词：图像处理 三维形貌测量 辅助参考线 空间映射 标定 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]