一种无需标记的在线三维测量方法

A New Method for Online Three Dimensional Inspection Without Marked

提出了一种无需标记的物体在线三维面形测量方法。将一固定的正弦条纹投影到待测运动物体上,借助物体运动产生等效的相移变形条纹。基于傅里叶变换轮廓术的调制度对各帧变形条纹计算,提取其具有某一特定分布的特征区域,采用相关度最大法,检测各帧变形条纹对应的调制度特征区域的位移量来检测出物体的移动,从而实现像素匹配,得到一组像素坐标完全一一对应的等效相移变形条纹图。利用Stoilov相移算法得到物体的截断相位,利用位相展开算法展开位相,通过位相和高度映射即可实现在线移动物体的面形测量。通过计算机仿真验证了该方法的可行性。

A new method for online three dimensional inspection without marked is proposed. When one sinusoidal fringe pattern is projected on the moving object, the deformed patterns with equivalent phase-shift caused by the moving action are captured by the CCD. Because the pixel coordinates of measured object at different deformed patterns are not corresponding to each other, the pixel matching must be done. The traditional method is helpful with some assistant marks to accomplish pixel matching. If the corresponding modulation distributions from each frame of the captured deformed patterns are calculated based on Fourier transfer profilometry, and extracting a particular region with some distinct features to perform correlation calculations the displacement between the adjacent captured deformed patterns can be picked-up, so as to realize the pixel matching. In this way, a set of equivalent phase-shift fringe patterns with the same pixel coordinate of measured object can be cut down from the captured patterns. The phase can be calculated by the Stoilov＇s algorithm, the unwrapped phase is achieved by using the unwrapped algorithms. So the 3D information of the online measured object could be reconstructed by the mapping from unwrapped phase to the height. The computer emulation result shows its feasibility.