基于点云与图像融合的BGA锡球检测方法研究  

Research on BGA solder ball detection method based on point cloud and image fusion

作　　者：汪威[1] 吕斌 杨轶睿 胡新宇[1] 黄玉春[2] Wang Wei;Lyu Bin;Yang Yirui;Hu Xinyu;Huang Yuchun(School of Mechanical Engineering,Hubei University of Technology,Wuhan 430068,China;School of Remote Sensing and Information Engineering,Wuhan University,Wuhan 430072,China)

机构地区：[1]湖北工业大学机械工程学院,武汉430068 [2]武汉大学遥感信息工程学院,武汉430072

出　　处：《电子测量技术》2022年第9期140-146,共7页Electronic Measurement Technology

基　　金：国家自然科学基金(61976083)项目资助。

摘　　要：为实现球栅阵列封装芯片视觉检测中焊球质量和共面度在线检测,提出一种点云与图像数据相结合的检测方法。首先对彩色相机进行标定,再分别获取芯片彩色图像和点云数据,利用随机采样一致性算法获取点云主平面法向量,根据法向量提供的倾角信息,进行倾斜度校正。然后,将倾斜度校正后的点云利用彩色相机内外参数投影成像得到点云灰度图,将其与彩色图像进行点模式匹配,获取点云数据与彩色图像间的平移量和偏转角,完成点云数据与图像数据配准。从配准后的数据提取焊球进行焊球大小、破损、变形、桥连等缺陷检测和高度测量,完成焊球共面度测量。该方法与迭代最近点法进行了对比实验。二者测量结果总体一致,但本文方法在耗时上减少了62.8%。该方法在先进制造业中具有广阔的应用前景。To realize online detection of solder ball quality and coplanarity in Ball Grid Array chip visual inspection, a detection method combining point cloud and image data is proposed. First, the color camera has been calibrated, the chips color image and point cloud data were acquired, and the unit normal vector of the main plane in the workpiece is achieved by Random sample consensus. The point cloud is rotated to fulfill the tilt of the point cloud alignment. Then, the rotating point cloud is projected and imaged by the color camera’s internal and external parameters, to produce the point cloud grayscale image, which is matched with the color image in point mode, and the translation amount and deflection angle between the point cloud data and the color image are obtained to complete the point cloud. In this way, the point cloud data is registered with the color image data. The solder ball is extracted from the registered data to determine its size, breakage, deformation, bridge, and other faults, as well as to measure its height and complete the solder ball’s coplanarity measurement. To perform comparison trials, this method was compared with the ICP algorithm. Two measurement results show that the proposed method can save 62.8% of the time, which also has consistent detection results. The proposed method for 3 D point cloud has a wide application prospect in advanced manufacturing.

关 键 词：球栅阵列 点云校准 点云灰度图 点模式匹配 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术] TN407[自动化与计算机技术—计算机科学与技术]