微尺寸视觉精密检测系统设计

Design for Precision Measurement System Based on Machine Vision

微小零件 (微尺寸 )几何量的精密测量 ,是当前精密加工、测量和装配中的一个难点。传统的接触式测量 ,极易破坏工件和改变零件的相互位置。基于机器视觉的高精度几何量测量系统 ,既具备了非接触式测量的优点 ,同时也有较高的性价比 ,是机器视觉技术在该领域中的一次成功应用。它采用在改进的Canny边缘的梯度图像上进行二次曲面拟合 ,获取零件精确边缘 (轮廓 )的方法 ,实现了对其相关几何量进行精密测量 ;同时 ,还解决了自动对焦 ,自动跟踪 ,数据自动“缝合”以及高精度和小视场之间的矛盾及光源等技术难题 。

It is difficult to measure the geometric quantity of small parts in finishing, assembling and measuring, because it's easy to break the workpieces' surface and alter their position by means of traditional contact measuring methods.There are some non contact measurers, such as,light feeler pin and interference microscope etc., because of it's high price and strict working conditions,so it's difficult to promote them in widely use. Precision measurement system based on machine vision has the advantages of non contact measuring as well as high performance and low price. Some problems, such as light source, algorithm of edge fitting, auto focusing,are discussed.