【作者】 李波；

【导师】 张铁；

【作者基本信息】 华南理工大学 ， 机械设计及理论， 2015， 硕士

【摘要】 工业机器人的现场应用以示教再现模式为主,作业过程中缺乏柔性。当工件的实际位置与示教焊接轨迹时的标准位置之间存在偏移和旋转时,若不对示教焊接轨迹加以修正,将导致机器人不能理想地对工件进行焊接,会出现焊接跑偏、焊接不完全甚至是碰撞等严重后果。需要利用传感设备检测出工件实际位置与标准位置之间的偏转量,并设计轨迹修正模型与算法对示教焊接轨迹加以修正,以实现机器人自动化焊接的目的。考虑到工业焊接车间恶劣的工作环境,本文利用抗干扰性强的二维激光传感器代替传统的CCD等成像设备对工件进行检测定位,开发了基于激光视觉传感的机器人焊接轨迹修正系统。第一步,论文首先对安川NX100六自由度工业机器人进行了简要的运动学分析,探讨了机器人各个关节坐标系之间的变换关系与机器人学中的姿态描述,为后文的工作打下了基础。第二步,对二维激光传感器的手眼标定进行了研究,提出了单点手眼标定算法,在此基础上又提出了五点标定算法,求解了激光传感器测量坐标系与机器人末端坐标系之间的姿态关系。第三步,对激光扫描成像技术的原理进行了研究,为后续工作打下了理论基础。通过提出点云数据的处理算法,排除了噪声数据的干扰,插补使得激光扫描采样数据的客观准确度、精度与密度得到了提升。提出了根据反映三维形貌的点云数据来生成二值化图像的算法,对工件进行成像的目标得以实现,通过图像匹配检测出工件的偏转量。第四步,建立焊接轨迹修正模型,提出了一套算法,通过坐标系之间的换算,成功利用机器视觉检测出的偏转量对机器人示教的轨迹进行校正。在文章的最后,对上述所描述的算法进行了实验验证,证明其可行性与正确性。更多还原

【Abstract】 Teaching and playback is the main mode of industrial robot’s application field, being lack of flexibility during its process of operation. When there are deviation and rotation between the actual location of the workpiece and its standard position used to teaching the welding trajectory, if not to modify the teaching welding trajectory, the robot cannot to welding of artifacts ideally, it will appear the following phenomena such as welding wandering 、 welding incompletely and even collision. It is necessary to use sensing equipment to detect the amount of deflection between the actual position of workpiece and its standard position and design trajectory correction model and algorithm for modifying the teaching welding trajectory to achieve the purpose of robot welding automatically. Considering the harsh working environment of industrial welding workshop,this paper uses two-dimensional laser sensor with strong anti-interference to replace the conventional CCD, etc. imaging equipment to detect and locate the artifacts, develops a system of robot welding trajectory correction based on laser vision sensing.Firstly,this paper performs kinematics analysis for Yaskawa NX100 industrial robot with six degrees of freedom, discussing the transformation relationship between the each joint coordinate of robot and the description of gesture in robotics, laid the foundation for later work.The second step,this paper studies the hand-eye calibration of the two-dimensional laser sensor, proposes simplified single point calibration algorithm innovatively,based on this, puts forward the single points calibration algorithm, solves the transformation relationship between the measuring coordinate system of Laser sensor and the coordinate system of the robot end flange.The third step, studying the principle of laser scanning imaging technology, laid a theoretical foundation for the follow-up work. Through putting forward the processing algorithms for point cloud data, rules out the interference of t noise data, interpolation makes the objective accuracy, precision and density of laser scanning sampled data improved. Proposing the algorithm to generate the binary image according to the point cloud data reflecting the 3d morphology, achieves the purpose of imaging for work pieces,detects the amount of work pieces’ s deflection by image matching.The fourth step, establishing the model of welding trajectory correction.Putting forward a set of algorithms, through the conversion between coordinate systems, successfully use the amount of deflection detected by machine vision to correct the teached trajectory of robot.At the end of this paper, the experiments are carried out to verify the algorithms described above, to prove their feasibility and correctness.更多还原