狭小空间旋转电弧传感四轮驱动全轮转向移动焊接机器人关键技术研究

Mobile mechanism and seam tracking sensor is the primary and key technology in realization of mobile welding.There are a large number of welding seam in narrow space of large weldments. It is difficult for worker to weld these seams. Based on the research and development of mobile welding robots and mobile robots at home and abroad, a new type of four-wheel- drived mobile robot mechanism has been put forward. This robot adopts full-wheel steering and permanent magnetic adsorption technology. What's more, this robot takes rotating arc sensor as seam tracking sensor.Firstly, the analysis on kinematics and dynamics of the robot mechanism were carried on. Some motion parameters which make the robot move without slip will be figures out.Secondly, in order to resolve the problem of attractive force decreasing rapidly with the increase of the air gap and the improvement of magnetic utilization , the research on distribution law of the magnetic field and stress field about the new-type permanent magnetic adsorption system has been carried out. What's more, three-dimensional numerical simulation and optimization and relative experiment has been carried out. As to the difficulties of motion accuracy、flexibility and load force, a new magnetic wheel structure which mix with the rubber has been put forward. In order to learn about the relationship between the magnetic distribution and structure of the wheel and the friction force and flexibility, three-dimensional numerical simulation and optimization and relative experiment has been carried out, which provide evidence for the design of the wheel.Traking the influnence of gravity ot welding pool into consideration,the research on mathematical model of high speed rotating arc sensor for all-position welding and algorithm which used to detect and modify the spatial attitude of welding gun base on charcateristisc plane method will be carried out.

移动机构和焊缝跟踪传感器是实现移动焊接的首要关键技术。针对大型焊件中存在的大量狭小空间焊缝难以焊接问题，在所研发的多个移动焊接机器人及国内外移动机器人基础上，提出一种以旋转电弧传感的新型四轮驱动全轮转向磁吸附式全位置移动机器人机构。首先对机器人机构进行运动学和动力学分析,无滑移运动参数；其次对提出的新型磁吸附系统进行磁场与力场分布规律研究，并通过三维数值仿真与优化及磁吸附试验，提高磁能利用率的同时解决磁吸附时间隙增大后吸附力迅速下降问题。针对运动准确性、灵活性与负载力的难点，提出一种复合橡胶磁轮结构，通过三维磁场数值仿真与优化及轮子动力试验，研究其磁场分布、轮子结构与其摩擦力、灵活性关系，为设计最优轮子结构提供依据。.考虑焊接熔池受重力影响，研究高速旋转电弧传感器全位置焊的数学模型及特征平面法焊枪空间姿态检测修正算法，进行全位置焊旋转电弧传感焊枪空间姿态识别。

针对大型焊件狭小空间焊缝焊接难题，项目主要研究了满足该焊缝要求的旋转电弧传感四轮驱动全轮转向移动焊接机器人系统。具体研究工作有：提出并实现了移动焊接机器人新型悬浮磁路设计、磁场有限元仿真及设计，增加移动焊接机器人稳定性与越障能力；提出了双水冷结构旋转电弧传感器，在对水冷效果进行数值仿真基础上，研制了双水冷结构紧凑的旋转电弧传感器；研制了无滑移的旋转电弧传感四轮驱动全轮转向移动焊接机器人一套，其转弯半径为0，负载能力180kg；建立了无滑移四轮驱动全轮转向移动焊接机器人运动学模型；建立了基于实际熔池形状的旋转电弧传感理论模型，提高了旋转电弧传感理论模型的精度；采用基于特征平面法的旋转电弧传感偏差提取方法实现焊缝偏差识别。采用田口法对旋转电弧焊接工艺参数进行了优化，获得较好的焊接工艺参数；实现四轮驱动全轮转向移动焊接机器人的平面斜线与曲线角焊缝跟踪焊接；培养硕士11名，其中毕业8名。发表论文12篇，EI收录2篇，另外，EI刊源录用论文1篇；获得授权专利3项；. 由于旋转电弧传感器改进较多及机器人结构复杂，在旋转电弧传感器与机器人加工存在不少问题，旋转电弧传感器与机器人都经过多次修改加工后才成功，故机器人立焊与仰焊焊缝跟踪实验未来得及完成。但旋转电弧传感器与机器人目前性能完全达到之前设计目标，而且实现了平面弯曲焊缝跟踪。