为提高线结构光传感器(LSLS)的标定精度,提出了一种基于平面参考靶标的标定方法。给出了相机坐标系下参考靶标点中心坐标及激光平面方程的计算方法;将参考靶标点中心向激光平面投影,并以左下角投影点为原点建立世界坐标系,得到了靶标点中心像素坐标所对应的世界坐标;采用多项式拟合得到了任意像素点到世界坐标的转换关系,实现了传感器的标定,标定结果仅为多项式的系数,便于存储和使用;对标定误差进行了分析。结果表明,所提方法得到的各测试点与第一个点间距离误差的均方根值为0.0216 mm,相对于传统方法减少了22%,所提方法在LSLS高精度标定方面具有一定的优越性。

To enhance the calibration accuracy of the line structured light sensor (LSLS), we propose a novel calibration method based on the planar reference target. A method is brought out to calculate the coordinates of the reference target point centers and the laser plane equation in the camera coordinate system. These reference target center points are projected onto the laser plane. The world coordinate system is established with the projection point of the lower left corner as the origin. The corresponding world coordinates for each center of the target point, which has known pixel coordinates, can be obtained. The mapping relationship between the arbitrary pixel coordinates and the world coordinates is achieved via the polynomial fitting and the calibration of sensor is finished. The calibration results are the coefficients of the polynomials, which are convenient for storage and use. The calibration accuracy is analyzed. The results show that the root mean square of distance error between each testing points and the first point is 0.0216 mm, which is 22% lower than the classical method. The proposed method has certain advantages in high-precision calibration of LSLS.