基于定位点的单目流动式测量技术

The Technology of Monocular Vision in Measurement Based on Fixed Target

针对加工车间对零件进行高精度、大尺度的现场实时测量的需求,对可实现在线测量的可移动式视觉测量技术进行研究,提出了一种基于单目视觉的新型便携式测量系统,可实现大尺度工件的三维精确在线测量。通过手持单个摄像机对固定位置的编码点靶标进行拍摄,通过对靶标图像的信息提取,确定摄像机在三维空间中的位姿,标定出安装在摄像机底部的探针相对于摄像机的位置关系,求解探针与被测物体的接触点的三维坐标。实验结果表明,本文系统对大型工件可实现高精度测量,三维测量精度在测量系统坐标系下x轴、y轴、z轴方向的稳定性误差分别为0.18mm,0.24mm和0.21mm;测量最大误差为0.35mm,可以满足工业现场对大尺度工件三维在线测量的精度要求。

In order to meet the demand of high precision, large scene and real time measurement of workpiece in machining workshop, this paper studies the movable vision measurement technology which can realize on-line measurement and designs a new portable measurement system based on monocular vision, which can realize the full-scale accurate measurement and positioning of the object with high efficiency. Take an image of the target with coded points in a fixed position by holding a single camera with hand,according to the analysis of target image, determine the position and orientation of the camera in 3D space. And calibrate the relative position between the camera and the probe, which is mounted at the bottom of the camera to solve the 3D coordinate between the probe and the object under measurement. Experimental studies show the proposed method can realize high precision measurement, the stability errors in the x-axis, y-axis, z-axis directions of the world coordinate system are 0.18 mm, 0.24 mm, 0.21 mm, and the maximum measuring error is 0.35 mm. It can meet the precision demand of large-scale, online measurement.