利用摄影测量在线检测轨道车辆车体运行姿态

轨道车辆运行时产生的各种振动导致车体相对于轨道的运行姿态发生变化，提出利用面阵相机和线激光组合的摄影测量方法在线检测车体运行姿态。检测系统安装在车体上可拍摄到轨面的任意位置(3点非共线)，选择激光在轨面投影的中点作为参考点，通过标定得到参考点在计算机图像坐标系和车体坐标系中的空间变换关系；车辆运动过程中，面阵相机拍摄线激光在轨面上的投影，将参考点在计算机图像坐标系中的坐标转化为车体坐标系中的坐标；结合参考点在轨面随行坐标系中的坐标特性，解算车体相对于轨道的坐标系转换，建立描述车体相对于轨道实时运行姿态的数学模型；构建检测系统，通过车体振动模拟平台及现场实车试验，验证了检测系统的可靠性。

On-line Detection of Car-Body Running Attitude for Railway Vehicle Based on Photogrammetry

The running attitude of car-body relative to the track will change because of various vibrations during railway vehicle operation. In this paper, a photogrammetric method based on area array camera and line laser is proposed to measure running attitude of car-body. Firstly, the system is installed at any position of the car-body as long as being able to scan the track and all three positions are non-collinear; the middle point of line laser projection on rail surface is selected as the reference point; and the calibration method is proposed to build the space coordinate transformation of the reference point between image coordinate system and vehicle coordinate system. Secondly, the area array camera will shoot the projection of line laser on rail surface, and the coordinate of the reference point in image coordinate system will be converted into the coordinate in vehicle coordinate system during operation. Then, the mathematical model is established to obtain the running attitude of car-body through coordinates transformation of three reference points in the vehicle coordinate system. Finally, the detection system is built and experiments were carried out both on the car-body vibration simulation platform and the real vehicle. The comparative results verify the reliability of measurement system.