SMT封装电路板三维在线检测技术

Three-Dmensional Online Inspection Technique for SMT Packaging Circuit Board

为了检测回流焊接之后SMT(Surface Mount Technology)封装电路板是否存在缺陷,设计并搭建了基于线结构光传感器的SMT封装电路板三维在线检测系统,通过线结构光扫描测量,获取SMT封装电路板表面三维数据。采用双传感器测量技术,有效减少数据丢失;研究了双传感器统一标定技术,可同时实现两个传感器的参数标定和坐标系统一。提出了自适应光条中心提取算法,对反射或散射影响而形成的光条图像噪声具有很好的抑制效果,能够提取准确的光条中心。实验表明系统测量精度可达到0.02 mm。系统测量得到的三维数据,可以为在线检测SMT封装电路板缺陷提供可靠的三维信息。

In order to inspect whether the SMT packaging circuit board is defective,this paper designed and established a three-dimensional online system based on structured-light sensors. Defects in the SMT packaging circuit boards can be found and identified online profit from the three-dimensional processing and analysis by using the system. Dual sensors measurement technology was applied to solve the problem of information occlusion effectively,which caused by the height difference of components. Dual sensor unified calibration technology was investigated,which can obtain model parameters of the two sensors simultaneously and realize unified coordinates at the same time. An adaptive accurate algorithm for extracting the stripe center was proposed,which can restrain image noise caused by light reflected and scattered effectively. Experimental results indicate that the measuring precision of the system can be 0. 02 mm. Three-dimensional data that obtained by the measurement system can provide a reliable three-dimensional information for the SMT packaging circuit board defects online inspection.