基于激光点阵的TIG焊熔池自由表面三维形貌测量方法  

Method to Measure Three Dimensional Specular Surface of TIG Weld Pool Based on Dot-matrix Laser Pattern

作　　者：张刚[1] 石玗[1] 黄健康[1] 张伟杰[2] 樊丁[1] 

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,兰州730050 [2]肯塔基大学生产制造中心

出　　处：《机械工程学报》2014年第24期10-16,共7页Journal of Mechanical Engineering

基　　金：国家自然科学基金(51205179);兰州理工大学红柳青年杰出人才培养计划(J201201);陇原青年创新性人才扶持计划;甘肃省高校基本科研业务费专项资助项目

摘　　要：测量弧焊熔池自由表面三维形貌对研究电弧与熔池耦合作用机理,控制焊缝成形及全熔透等有着重要意义。针对现有的三维测量方法难以应用于强弧光、熔池表面镜面反射情况,提出一种点阵激光测量熔池自由表面三维形貌的新方法。通过分析建立熔池自由表面反射成像激光点与投射激光点之间的映射模型,提出基于投射激光点更新的熔池自由表面三维恢复算法。重建连续钨级惰性气体保护焊(Tungsten inert gas arc welding,TIG)熔池自由表面三维形貌,提取其宽度和高度尺寸,并与实际测量结果进行对比。结果表明,点阵激光测量法不仅有效避免弧光干扰实现了熔池自由表面的动态测量,而且重建的熔池自由表面三维形貌几何尺寸变化与实测结果吻合较好,宽度和高度误差分别为1.73%,2.32%,为更好地研究TIG焊熔池自由表面行为演化规律提供一种新方法。Measuring three dimensional（3D） weld pool surface of tungsten inert gas arc welding（TIG） has significance for investigating coupled mechanism between welding arc and weld pool, control of weld formation and weld joint penetration. However, the influence of strong arc light and the specular reflection of weld pool surface make the existed methods hardly applied to 3D measurement. To this end, a new sensing method is proposed, which utilizes the reflected property of weld pool surface. The mapping model between reflected and projected laser dots is analyzed and established. A new 3D reconstructed algorithm is proposed based on the renewed projected laser dots and the 3D TIG weld pool surface is achieved, also its geometry parameters, i.e., width and average height are extracted. Compared the measurement shows that the proposed method can measure the dynamical variation of weld pool surface, but also the reconstructed result coincides with the measurement well. The error of weld pool’s width and height is 1.73% and 2.32%, respectively. To better investigate the evolution rule of TIG weld pool specular surface provides a new method.

关 键 词：熔池自由表面 激光点阵 镜面反射 三维测量 

分 类 号：TG409[金属学及工艺—焊接]