基于多编码块标定板的多相机外参全局标定

A Global Calibration Method of Multi-Camera Extrinsic Parameters Based on Multi-Coding Block Combined Calibration Board

多相机测量系统会因较小的重叠视野与环境干扰而导致外参标定失败,因此提出了一种基于多编码块组合型标定板的多相机外参标定方法。首先,设计了一种平面标定板,它由多个具有独立编码信息的编码块组合而成;其次,研究了编码块特征点的提取与管理方法;最后,通过重建特征点并优化重投影误差,实现了各个相机外参的全局标定。实验结果表明,该方法能够适应各相机无法同时观测完整标定板的情况,并且有标定后的测量误差为0.014 mm,标准差为0.112 mm。因此,提出的方法能够实现多相机测量系统全局外参的高精度快速标定。

The multi-camera measurement system may fail to calibrate extrinsic parameters due to small overlapping field of view and environmental interference.Therefore,an extrinsic calibration method based on the multi-coding block combined calibration board is proposed.Firstly,a planar calibration board is designed,which is composed of several coding blocks with independent coding information.Secondly,the method of extracting and managing feature points is studied.Finally,by reconstructing feature points and optimizing the reprojection error,the global extrinsic calibration of the system is realized.The experimental results show that the proposed method can adapt to the situation that cameras cannot observe the complete calibration board at the same time.The measurement error after calibration is 0.014 mm,and the standard deviation is 0.112 mm.Therefore,the proposed method can realize the high-precision calibration of the multi-camera measurement system.