一种采用相位测量轮廓术的工件在线三维检测方法

A Three Dimensional On-line Inspecting Method for Workpiece by PMP

提出了一种基于相移轮廓术在线检测工件三维信息的方法.利用计算机编程产生的一固定正弦光栅图通过数字投影机投射在流水线的一段区域,无需专门的相移装置,当物体在线移动穿过此区域时,使用计量光栅等距离定位发信,控制CCD采集五帧变形条纹图,并采用具有一定特征的标记实现五帧变形条纹图间的亚像素级像素匹配,提取相移变形条纹图,由Stoilov算法计算,得到工件表面截断相位,展开后可得到物体表面三维信息.实验验证了其可行性.

A new three dimensional （3D） on-line inspecting method for workpiece is proposed. Only one fixed sinusoidal grating pattern produced by computer is projected onto a special inspecting area of the production line through digital light processing （DLP）. Specialized phase-shifting device is not needed. When the workpiece goes through the area,a metrologic grating is applied to send CCD signals at intervals of a certain invariant displacement to capture five deformed patterns synchronously. Pixel matching of these five patterns is processed by a set of symbols with special features at higher precision of sub-pixel level to redraw the five phase-shifting deformed patterns. The discrete phase can be calculated by Stoilov＇s algorithm and the 3D information can be reconstructed by phase unwrapped. The experimental result shows its feasibility.