基于线结构光单平面标定的3D成像方法研究

A high accuracy and robustness 3D imaging method for line structured light single plane calibration

针对现有线结构光3D成像系统标定步骤繁琐、标定鲁棒性低等问题,本文提出了基于线结构光单平面标定的3D成像方法,实现高精度、高鲁棒性的3D成像。该3D成像方法通过构建结构光平面到成像面的单平面映射模型简化了三维空间的标定步骤,提高了系统的鲁棒性。该模型基于棋盘格图像内角点坐标作为线结构光平面标定计算控制点,提高了标定控制点个数和降低了标定的偶然误差;该模型无需进行成像系统内外参矩阵估计,精简了标定中间步骤;该模型无需计算线结构光图像光条中心点,避免了图像算法误差对标定结果的影响。实验结果表明,该3D成像方法标定步骤简单,标定控制点多、鲁棒性高,标定平均距离残差0.158 mm,单点的重复性测量精度优于±1μm。

The existing wired structured light 3D imaging system has the problems of tedious calibration steps and low robustness.To address these issues,this paper proposes a 3D imaging method based on the single plane calibration of linear structured light,which could achieve high accuracy and high robustness of 3D imaging.The 3D imaging method simplifies the calibration steps of 3D space and improves the robustness of the system by constructing a single plane mapping model from the structured light plane to the imaging plane.In this model,the coordinates of the corners in the checkerboard image are used as the control points for the calibration of the line structured light plane,which improves the number of control points and reduces the accidental error.The model does not need to estimate the internal and external parameter matrix of the imaging system,which can simplify the intermediate steps of calibration and improve the repeatability and accuracy of calibration.In addition,the model does not need to calculate the center point of the light stripe in the line structured light image,which avoids the influence of image algorithm errors on the calibration results.Experimental results show that the calibration procedure of the 3D imaging method is simple and has many calibration control points.The robustness of the calibration is high,the calibration average distance residual is 0.158 mm,and the repeatability measurement accuracy of single point is better than±1μm.