全位置管道焊接的纯滞后激光视觉跟踪技术

Pure Hysteresis Laser Vision Tracking Technology for All Position Pipe Welding

在机器人视觉引导中,激光线投射位置往往与焊枪头位置存在一定的偏差值,导致在焊缝形状多变的情况下实时纠偏精度较低。因此,提出一种基于Smith预估控制模型的纠偏方法。首先,以形态学中的skeleton和矩形开运算为核心算法提取出焊缝中心点。然后,根据焊缝中心点计算出纠偏量,将纠偏量按顺序存入容器中,采用Smith原理构建的数学模型对存储的数据进行处理。最后,使用处理后的数据逐点进行滞后纠偏。数据仿真和实际测试结果表明:实际纠偏精度在0. 35 mm以内,满足工程焊接对纠偏精度的要求,具有很强的实用性。

In robot visual guidance,the laser line projection position often has a certain deviation from the position of the torch head,resulting in low real-time correction accuracy in the case of variable weld shape. Therefore,a correction method based on Smith predictive control model was proposed. Firstly,the center point of the weld was extracted by using the skeleton and rectangular opening operations in morphology as the core algorithm. Then,the amount of correction was calculated according to the center point of the weld,and the amount of correction was stored in the container in order. Moreover,the mathematical model constructed by Smith principle was used to process the stored data. Finally,the processed data was employed to perform lag correction point by point. The results of data simulation and actual test show that the actual correction accuracy is less than 0. 35 mm,which meets the requirements of correction accuracy in engineering welding with strong practicability.