基于平面互补靶标的线结构光标定系统

为提升线结构光传感器的标定效率与精度，设计了一种集成自背光可调节位姿的平面棋盘格-同心圆互补线结构光标定系统。该系统基于同心圆圆心的真实投影位置与投影椭圆圆心位置的几何关系，建立非线性优化偏心误差补偿模型，精确得到透射投影下圆心偏心误差补偿位置。该方法与传统标定方法对比降低重投影误差84.7%，有效解决了圆形标志物偏心误差补偿的高精度标定难题。通过将相机坐标系下过光心、光条中心线的平面与靶标平面结合，多次获取空间交线的坐标信息增加特征点，并使用最小二乘法拟合光平面方程，解决了因特征点少从而平面拟合标定精度较低的问题。在复杂环境下重复实验测得大尺寸砂轮外径误差均值为0.005 1 mm，结果表明该标定系统具有一定的准确性和简便实用性。

Line structured light calibration system based on planar complementary target

To improve the calibration efficiency and accuracy of line structured light sensor, a plane checkerboard and concentric circle complementary line structured light calibration system was designed integrating with self-backlighting and pose-adjustable functions. Based on the geometric relationship between the real projection position of the concentric circle center and the center of projection ellipse, the nonlinear optimized compensation model for eccentric error was established, which precisely determined the eccentric error compensation position of the circle center under the perspective projection. Compared with the traditional calibration method, the proposed method reduced the re-projection error by 84.7% and effectively solved the problem of high-precision calibration for eccentric error compensation of circular markers. By combining the plane passing through the optical center and the center line of the light bar with the target plane in the camera coordinate system, the coordinate information of the spatial intersection lines was obtained for many times to increase the feature points, and the problem of lower calibration precision of plane fitting due to the fewer feature points was solved by using the least square method to fit the optic plane equation. In complex environments, the average error of the outer diameter of the large-size grinding wheel is 0.005 1 mm measured by repeated experiments, and the results show that the designed calibration system has certain precision, simplicity, and practicability.