基于ACT匹配的GMA增材制造熔池形貌三维重建  

Three-dimensional reconstruction of molten pool appearance in GMA additive manufacturing based on ACT stereo matching algorithm

作　　者：尹紫秋 熊俊[1] YIN Ziqiu;XIONG Jun(Key Laboratory of Advanced Technologies Materials,Ministry of Education,Southwest Jiaotong University,Chengdu 610036,China)

机构地区：[1]西南交通大学材料先进技术教育部重点实验室,成都610036

出　　处：《焊接学报》2019年第1期49-52,163,共5页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(61573293;51505394);四川省科技支撑计划资助项目(2015M580796)

摘　　要：基于双棱镜折射原理,设计了单摄像机虚拟双目视觉传感系统,系统达到亚像素精度.标定了左右虚拟摄像机内外参数及其关系,完成了图像对的极线校正.进一步优化了自适应权重Census变换立体匹配算法(ACT,adaptive Census transform),求取了校正图像对亚像素精度视差.三角测量法重建了标准圆柱体部分表面形貌.结果表明,标准件宽度误差优于3.17%,高度误差优于5.83%.以熔化极气体保护电弧(GMA, gas mental arc)增材制造熔池图像对为例,采用优化的ACT匹配算法求取了熔池图像对亚像素精度视差,基于三角测量法获取了熔池表面三维形貌.The virtual binocular vision sensing system was designed based on single camera through the refraction principle of biprism,the accuracy of which reached to subpixel.The intrinsic and external parameters of both virtual cameras and relative position were calculated,and the image pairs were rectified.Then,adaptive Census transform(ACT)stereo matching algorithm was optimized for calculating the parallax of the rectified image pairs with sub-pixel accuracy.The three-dimensional appearance of a standardized cylinder was reconstructed through the triangulation method.The results showed that the width error was less than 3.17%and the height error had a maximum of 5.83%.The image pairs of molten pool in GMA additive manufacturing were taken as an example,while the parallax with sub-pixel accuracy of the image pairs was calculated based on the optimized adaptive Census transform stereo matching algorithm.Finally,the three-dimensional appearance of molten pool was obtained via the triangulation approach.

关 键 词：GMA增材制造 熔池形貌 三维重建 自适应Census变换 

分 类 号：TG442[金属学及工艺—焊接] TG115.28