接触线几何参数CCD交汇测量分辨率及精度分析

采用双CCD交汇测量技术对电力机车接触导线磨损面边界点进行精确定位,可以实现导线高度、拉出值、磨损宽度等几何参数的非接触实时测量,而边界点定位精度及分辨率会受测量系统的光学参数、结构参数等的影响.基于交汇测量机理,推导出了接触线几何参数测量的表达式,详细分析了分辨率和测量精度与边界点位置、CCD像元尺寸、成像镜头焦距、两CCD之间的距离、交汇仰角等参数之间的关系,并进行了数值模拟.在此基础上,结合测量条件及技术指标完成了各参数的优化设计,得到了理论上能达到的最佳测量精度和分辨率,同时对测量装置的制作和安装提出了合理化的建议.

Resolution and accuracy analysis of CCD intersection measuring on contact wire geometry parameters

Dual CCD intersection measurement techniques are used for precise positioning the abrasive surface boundary points of electric locomotives' contact wire, the wire height, stagger values, abrasive width and other geometric parameters can receive non-contact and real-time measurements. The accuracy and resolution of positioning boundary points are limited by optical parameters of the measurement system, the impact of structural parameters, and so on. According to the dual CCD intersection measurement principle, a mathematics model of contact wire geometry measurement was established, the resolution and accuracy of the boundary positions, CCD pixel size, the imaging lens focal length, the distance between the two CCD, the relationship between intersection angle, and other parameters were analyzed in detail, and numerical simulations were made. Based on this, by means of the measurement conditions and technical specifications, the optimization of the parameters was completed, the optimum measurement accuracy and resolution which theoretically can be achieved was obtained, and meanwhile, rational measures were put forward for the production and installation of measuring devices.