作　　者： ; ; ; ;

机构地区： 中国科学院

出　　处： 《机器人》 2014年第6期744-750,共7页

摘　　要： 针对大型金属薄壁零件制造、装夹变形后的空间曲线焊缝加工轨迹尤其是零件空间法矢难以确定的问题,提出了一种通过测量焊缝上离散点计算刀位点并估计空间法矢的方法.首先,利用搅拌摩擦焊接(FSW)机器人末端安装的接触式测头碰触焊缝进行测量,再利用三次样条拟合一系列测得的空间点,得到一条与真实焊缝距离为1倍测头球心半径的空间曲线;其次,通过最小二乘法求出众多测量点的最小二乘平面;以最小二乘平面内焊缝曲线投影的面内法矢估计实际焊缝曲线的空间法矢.最后,将拟合曲线上用弦高差法离散得到的伪刀位点沿其空间法矢的负向平移1倍测头球心半径的距离,作为真正的刀位点.仿真实验表明本文的研究为大型复杂薄壁回转体零件的搅拌摩擦焊接提供了一种不必测量整个曲面便可得到焊接刀位点和法矢的有效方法. For the large thin-walled metal part, it is difficult to determine the spatial weld curve when it deforms due to manufacturing or clamping, especially the spatial normal vectors of the part. To solve this problem, a method is presented to estimate the spatial normal vector and calculate cutter location points by measuring the discrete points on the weld joint. Firstly, a contact-type probe fixed in the end of FSW （friction stir welding） robot is used to touch the weld joint to measure a series of space points. By fitting these points with a cubic spline curve, a spatial curve which is one probe radius long distance from the real weld curve can be obtained. Secondly, the least square plane of the measured points is solved by the least square method. Then, the planar normal vectors of the projection curve in the least square plane are used to estimate the spatial normal vectors of the real weld joint curve. At last, fictitious cutter location points discretized by the chord height error algorithm on the fitted curve are moved along the direction of their space normal vectors by one probe radius distance to get the real cutter location points. Simulation experiment demonstrates the effectiveness of the proposed method. Using the method, cutter location points for welding and normal vectors can be obtained without measuring the entire surface of the large thin-walled complex rotating parts in FSW.

关 键 词： 焊接机器人 搅拌摩擦焊 焊缝测量 轨迹生成

领　　域： [自动化与计算机技术] [自动化与计算机技术]