介绍了自由形状零件截面轮廓测量系统的硬件结构,在测量方法上采用牛顿插值法实现图像的亚像素边缘检测,将轮廓尺寸测量问题转化为求取最大相关函数的问题,采用了基于仿射变换的最大相关搜索策略,根据实际需求和边界直径对搜索的初始参数加以约束,大大减少了搜索时间。利用标定确定摄像机的比例因子和系统精度,实验给出了最大相关度量和仿射参数的函数关系,证实该方法是快速有效的。 The hardware structure of free-form part profile measurement system is introduced. Newton interpolation method is used to detect the sub-pixel edge of the image, and the problem of measuring the contour size is transformed into the problem of obtaining the maximum correlation function. The maximum correlation search strategy, according to the actual demand and the boundary diameter of the initial parameters to be constrained search, greatly reducing the search time. Using scaling to determine the camera scale factor and system accuracy, the experiment gives the maximum correlation function as a function of affine parameters, which proves that this method is fast and effective.