单目结构光扫描仪的系统标定技术研究  

Technical Study of System Calibration of Single Camera Structure-Light Scanner

作　　者：刘建伟[1,2] 侯军兴[1] 刘小波[2] 梁晋[2] 

机构地区：[1]郑州航空工业管理学院,河南郑州450015 [2]西安交通大学机械工程学院,陕西西安710049

出　　处：《机床与液压》2015年第13期12-17,共6页Machine Tool & Hydraulics

基　　金：国家自然科学基金项目(51105344);航空科学基金项目(2012ZD55009;2013ZD55007);河南省高等学校精密制造技术与工程重点学科开放实验室开放基金(PMTE201307A)

摘　　要：针对单目结构光扫描系统中投影仪难以准确标定的难题,通过分析投影仪的工作原理和投影特性,提出了10参数投影模型。将投影过程看作摄像的逆过程,借助于摄像机建立投影仪栅片图像和CCD像机图像的对应关系,提出了基于外差式多频相移的投影仪栅片图像生成方法。由拍摄和生成得到的标定图像,基于摄影测量原理分步实现了摄像机内参数、投影仪内参数和他们的相对外参数,实现了扫描仪的系统标定。结果表明:标定实验中用标定结果对标定板上的标志点进行重投影,重投影误差在0.08 pixel以下,具有较高的标定精度;经该方法标定出的单目结构光扫描仪测量标准球的绝对误差小于0.07 mm,能满足大多数物体型面的测量要求。Aimed at the problem of difficulty in the projector calibration of single camera structure-light scanner system, the pro- jection model with 10 parameters was proposed through analyzing working principle and projection characteristics. By considering the projection process as a reverse of video process, by the means of a vidicon, the corresponding relationship of CCD camera image and projector grating image was established. The generating method of a projector grating image was proposed based on heterodyne type mul- tifrequency phase shift. By the calibration image obtained through shooting and generating, based on video shooting measurement princi- ple, it was implemented step by step of a vidcon of internal parameters, the projector and their corresponding exterior parameters, and system calibration of the scanner was realized. The calibration experiment shows that this is a high-precision with re-projection error lower than 0. 08 Pixel, when the index point on the calibration board is projected again by calibration result. The absolute error for measuring standard ball is lower than 0. 07 mm using the Single-Camera Structure-Light Scanner calibrated by the proposed method to calibrate, which can satisfy measuring requirements for 3-D profiles of most objects.

关 键 词：外差式多频相移 投影模型 近景摄影测量 光束平差 系统标定 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]