基于三点透视模型的线结构光系统标定方法

针对现有线结构光传感系统标定过程中对设备要求高、标定过程繁琐等问题，提出一种基于三点透视模型的快速标定方法。引入一个可自由移动的平面靶标，靶标上只需要共线、且相互位置确定的三个特征点，利用共线三点建立三点透视数学模型，根据三个特征点以及光条纹在摄像机像面的成像信息，就可以获取光平面上标定点在摄像机坐标系下的坐标。平面靶标在视觉范围内任意移动几个位置，得到光平面上多个标定点坐标，从而确定光平面方程。实验证明，该方法平均相对测量误差小于0.8%。该方法不需要昂贵的辅助调整设备，也不需要求解坐标系之间的转换矩阵，简单、快速，适合现场标定。

Calibration method for line structured light sensor based on perspective-three-point model

A calibration method based on perspective-three-point was proposed to solve the calibration problems in line structured light sensor system such as requirement of high accuracy calibration model, complicate calibration procedure and so on. The calibration model used a coplanar reference target with three collinear and known distance points. The line across the three points intersected the laser stripe at a point that was called as the calibration point. The calibration point coordinates in the camera coordinate system can be calculated by using the imaging information of the three points and that of the light stripe on the camera’s image plane. The spatial pose between camera and light plane can be calibrated by moving the reference plane at several arbitrary places in the sensor range. Experiments show that the sensor can attain relative accuracy about 0.8%.The method decreased the cost of calibration equipment, and needn’t calculate the transformation matrix between different coordinate systems. The method is simple and flexible, and can satisfy the precision requirements