基于光学测棒的立体视觉坐标测量系统的研究

Study of Stereo Vision Coordinate Measurement System Based on Optical Probe

提出了一种基于测量与校准功能合一的光学测棒的立体视觉坐标测量系统。采用光学测棒作为成像目标,通过任意放置的两台摄像机获取测棒上的发光特征点的图像实现被测物体三维坐标的测量,同时利用测量数据定期对两台摄像机外部方位参数进行校准。深入研究了两台摄像机内部参数和外部方位参数校准过程中的校准件和校准算法的设计,以及系统测量建模等关键技术,提出了相应的解决方案,减小了摄像机内外参数校准及测量模型对测量结果的影响,提高系统的测量精度。实验结果表明,该系统的最大测量误差为0.11mm。

The paper proposes a stereo vision coordinate measurement system based on optical probe with the function of measuring and calibrating. The system adopts the probe as the imaging object and obtains the three- dimensional （3D） coordinate of the measured object by the images of the optical features on the optical probe got by the two cameras arbitrarily placed. During the measuring process, the extrinsic calibration parameters of the two cameras are calibrat calibrated termly with the measurement data. The key techniques, including the design of the calibration patterns and calibration algorithms of the camera intrinsic parameters and the extrinsic parameters online calibration of two cameras, and stereo vision measurement modeling, are studied. The corresponding schemes to reduce the effect of camera extrinsic and intrinsic parameters calibration and measurement modeling and improve precision are presented. The experimental results show the maximum error is 0.11 mm.