基于OpenCV的移动焊接机器人视觉系统自主标定方法

标定工作是实现机器人视觉计算的前提.根据移动焊接机器人工作场合的特殊性,基于OpenCV,提出一套针对手眼双目视觉系统的自主标定方法.自动提取角点,自主筛选有效标定图像序列,由亚像素角点提取结果求取相机内参数,由同时刻获取的标定图像对估算双目间几何矩阵,由标定板面在摄像机坐标系下位姿矩阵改变量间接求取摄像机运动矩阵,用最小二乘法快速计算出手眼关系.标定试验结果表明,相对于传统的Matlab标定工具箱,该方法能够满足用于机器人焊接的视觉系统所需标定精度,同时因无人为参与可很大程度地提高移动焊接机器人的自主性.

Auto-calibration method of vision system for mobile welding robot based on OpenCV

Calibration is a premise of visual computing for robot.According to the particularity of mobile welding robot’s workplace,a method for the auto-calibration of hand-eye binocular vision system based on OpenCV is given.Corners are extracted automatically,effective images are selected by itself,internal parameters are calculated based on the extracted result of corners with sub-pixel precision,geometry matrix between CCDs in pair is calibrated via images in pair captured at the same time,the motion matrix of sensor is got indirectly by computing the changed motion matrix of calibration board in the coordinate of sensor,then hand-eye relationship is caculated by least-square method.Calibration results demonstrate that the method can meet the calibration precision for vision system of mobile welding robot used for intelligent welding,meanwhile improve the autonomy because there is no human intervention compared with the traditional Matlab calibration toolbox.