基于环形激光的物体内表面扫描

Scanning Inner Surface of Object-Based on Ring Laser

为解决传统线激光扫描方法对于物体内部点云数据获取的局限性问题,提出一种基于环形激光的扫描方法。首先标定出相机的内外参数,进而利用透视投影原理得到激光锥面上部分三维点。然后利用最小二乘法求得相机坐标系下的圆锥曲面方程。使用Hessian矩阵算法进行光条纹中心提取,再利用锥面标定得到的方程对物体内部进行三维点云数据的获取。获取的点云数据绝对误差小于3mm,相对误差小于0.6%,获取点云速率达到20000p/s。上述方法具有精度高、高效简洁、鲁棒性好等特点,可用于管道或隧道内壁三维测量和检测。

In order to solve the limitation of the traditional line laser scanning method for the point cloud data ac-quisition inside the object,a scanning method based on ring laser is proposed.Firstly,the internal and external param-eters of the camera were calibrated,and then some three-dimensional points on the laser cone were obtained by the principle of perspective projection.Then the least square method was used to obtain the cone surface equation in the camera coordinate system.The Hessian matrix algorithm was used to extract the center of the light stripe,and then the equation obtained by the cone calibration was used to obtain the three-dimensional point cloud data inside the object.The absolute error of the acquired point cloud data is less than 3mm,the relative error is less than 0.6%,and the ac-quisition rate of the point cloud reaches 20000p/s.This method has the characteristics of high precision,high efficien-cy,simplicity,and good robustness,and can be used for three-dimensional measurement and inspection of the inner wall of pipelines or tunnels.