提出一种基于摄像机标定的非接触式接触线几何参数检测方法:在 Matlab 软件平台基础上,对 CCD摄像机采集到的接触线二维图像进行预处理;利用迭代阈值法,对图像中由车载激光器发射到接触线上所形成的激光光斑的中心点进行定位;最后,根据摄像机针孔成像模型,将该激光光斑点在图像坐标系中的坐标与该点由摄像机标定的世界坐标系中的三维空间坐标建立对应关系,并据其算出接触线的几何参数。将用此方法计算与用光学测量仪对同一段实际线路测量的结果进行比较得知,此方法求得的拉出值与光学测量仪的实测值之差小于11 mm,所得导高之差小于10 mm。该结果表明:此方法较准确地计算出接触线导高、拉出值,可满足检测的需求。
In this paper,the non-contact geometric parameters detection method for contact lines based on cam-era calibration was put forward.On the platform of Software Matlab,the contact line images acquired by the CCD camera were pretreated.Then,the center point of the image laser spot was located via the iterative threshold method.Lastly,with the camera pinhole model and camera calibration,the relationship between the two-dimensional coordinates of the laser spot in the image-coordinate system and the three-dimensional space coordinates of the laser spot in the world-coordinate system was established,and the geometric parameters were calculated in accordance.The proposed method was compared with results measured with the optical measuring instrument on the same section of actual lines.The stagger difference was less than 1 1 mm and the conductor height difference was less than 10 mm.It shows that with the proposed method the height and stag-ger of the contact line can be calculated accurately and the test requirements can be satisfied.