作者：李龙涛, 蔡兴

作者单位：上汽大众汽车有限公司，上海 201805

关键词：工程测量技术;焊接引导;视觉定位;机器人

摘要：

针对汽车生产线的车身定位焊接问题，提出一种基于视觉定位进而精确引导机器人焊接的方法。视觉车身定位系统由四个固定安装的相机组成，车身到位时，四个相机对车身四块区域的特征点进行拍照，结合特征点在数模上的三维坐标和图像上的二维坐标，实现车身坐标系的定位，进而引导机器人进行焊接。与传统的机械式车身定位相比，无需升降辊床落位，从而节省升降辊床的成本及落位的时间；另外，相机的拍照视场即为车身定位的有效区域，所以一套视觉车身定位系统满足多个车型进行定位的需求，具有柔性高的特点。以激光跟踪仪为评价基准，进行引导精度测试和焊接拉动量测试；以批量造车的2 000台车的焊接数据为基础，进行批量过车焊接精度分析。结果表明：所提出的基于视觉定位的机器人焊接引导方法有效，具有良好的定位精度，提高定位效率，满足车身焊接需求。

The method of robot welding guidance based on visual positioning
LI Longtao, CAI Xing
SAIC Volkswagen Automotive Co., Ltd., Shanghai 201805, China
Abstract: To solve the problem of car positioning in welding production line, a robot welding guide method based on visual positioning was proposed. The system consists of four fixed cameras. When the car is in place, the four cameras take pictures of the feature points in the four areas of the body. By combining the 3D coordinates of the feature points on the theoretical model and the 2D coordinates on the image, the position of car coordinate system is calculated, and then the robot is guided to carry out welding. Compared with the traditional mechanical car positioning, there is no need to go up and down for the lifting roller bed, thus the cost of lifting roller bed and the raising and falling time are saved. In addition, the camera’s field of view is the effective area of car positioning, so the system can meet the requirements of positioning for multiple car models with high flexibility. Taking the laser tracker as the standard of evaluating, the guiding precision test and welding pull test were carried out. Based on the data of 2 000 cars, the welding precision of batch passing cars is analyzed. The results show that the robot welding method based on visual positioning is effective, has good positioning accuracy and meets the needs of car welding.
Keywords: engineering measurement technology;welding guidance;visual positioning;robot
2021, 47(11):59-63  收稿日期: 2020-12-21;收到修改稿日期: 2021-02-15
基金项目:
作者简介: 李龙涛（1988-），男，山东济宁市人，工程师，硕士，主要从事汽车工艺规划工作
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