线结构光三维测量系统扫描方向的标定

Calibrate Method for Scanning Direction of 3D Measurement System Based on Linear-Structure Light

提出一种基于平面标靶的线结构光三维传感器扫描方向的标定方法。利用平面标靶对摄像头进行标定,得到摄像头的内部参数,将棋盘格平面标靶固定在空间某一位置,测量系统沿着扫描方向移动并采集一系列图像。根据这一系列图像求出摄像机的外部参数,并结合已经求出的摄像机内部参数计算出标靶上同一特征点在摄像机坐标系下的坐标值,对这些点进行直线拟合得到一直线方程,直线的方向就是测量系统的扫描方向。实验表明,该方法测量精度高,操作简单,无需辅助的调整设备,降低了标定设备的成本和系统校准的难度,适合现场标定。

A calibrating method for the scanning direction of 3D measurement system based on linear-structure light using a plane calibration board is proposed.In the calibration,the camera′s inner parameters are calculated with the plane calibration board first.Then the plane calibration board is placed on a position,the 3D sensor moves along the scanning direction and collects pictures at the same time.The outside parameters of the camera for every position of the 3D sensor are worked out.With these pictures and the camera coordinates of homologous points on each picture can be worked out with the inner and outside parameters.At last,linear equation is acquired by linear fitting with the camera coordinates of homologous points.The scanning direction is equal to the direction of the line.The experimental result shows that the method has high precision and it is practical in 3D measurement.