工业机器人因其良好的重复定位精度而被广泛应用于堆垛、搬运、焊接等工业领域,但其绝对定位精度低,限制了其在高精度制造领域的应用。通过构建工业机器人误差测量与在线补偿闭环控制系统,对工业机器人的误差进行在线补偿。该方法综合考虑了几何参数和非几何参数引起的误差,提高了其位姿精度。研究基于KUKA机器人传感器接口(Robotsensor interface,RSI)进行位姿误差补偿的性能。通过研究KUKA机器人末端姿态的表示方式,提出一种基于激光跟踪仪测量工业机器人末端姿态的方法,并设计试验研究机器人在其工作空间的位姿误差特点。对搭建的闭环控制系统进行位姿误差补偿试验验证了该系统的位姿补偿效果。试验结果表明,经过第二次在线误差补偿后,其绝对定位精度由原先的0.628mm提升到0.087mm,姿态精度接近0.01°。
The industrial robot has been widely used in industrial fields such as stacking, handling and welding because of its high repeatability. But its absolute positioning accuracy is poor, which limits its application in the fields of high precision manufacturing. By building an industrial robot errors measurement and online compensation closed-loop control system, the errors of the industrial robot are compensated on-line. This method takes into account the errors caused by geometric and non geometric parameters, and improves the position and attitude accuracy. The performances of position and attitude errors compensation based on the KUKA Robot Sensor Interface are studied. By studying the representation of the end attitude of the KUKA robot, a method is put forward to measure the attitude of the industrial robot based on laser tracker and the characteristics of the position and attitude errors of the robot in its workspace are studied experimentally. The position and attitude compensation effect of the closed-loop control system is verified by experiments. The experimental results show that the absolute positioning accuracy is improved from 0.628 mm to 0.087 mm and the attitude accuracy is close to 0.01 o after the second online errors compensation.