高景一号卫星影像在山区铁路制图中的精度研究

Accuracy Research in Mountain Railway Stereo Mapping Using SuperView-1 Satellite Images

为了研究高景一号卫星影像是否能够满足铁路1∶2000制图精度要求,在某铁路项目中采用该影像开展地形图绘制工作,在像对范围内均匀布设像控点,并在不同地形等级区域获取实测检查点用于后续精度检查,以及开展空三加密及定向立体采集地形图的工作,从统计地形图精度及人眼判释两方面考量制图精度。研究表明,绝对定向点残差、地形图平面中误差及高程中误差等精度指标均能够满足《铁路工程摄影测量规范》1∶2000地形图要求;受高景一号卫星影像分辨率限制,对点状细小地物判释效果弱于高分辨率的航空影像;高山地区域立体像对存在微小的上下视差,会对高程精度带来影响。研究结果表明,在航空影像不能快速获取时,高景一号卫星影像可以作为一个有效的数据源补充,其精度能够满足铁路1∶2000制图要求。

In order to study whether the stereo image pairs of SuperView-1 satellite can meet the accuracy requirements of 1∶2000 for engineering design,the image was used for topographic mapping in a railway project.Image control points were uniformly set up within the range of the image pairs and measured checkpoints in areas of different terrain levels were obtained for subsequent accuracy checks.Aerial triangulation and directional three-dimensional collection of topographic maps in the internal industry were carried out.The accuracy of mapping was evaluated from two aspects:statistical accuracy of topographic maps and human eye interpretation.The research results show that,the absolute orientation point residuals,the accuracy indicators of using field inspection points to calculate the plane and elevation errors of topographic maps,all of which can meet the requirements of the 1∶2000 scale topographic map in the“Railway Engineering Photogrammetry Specification”.Due to the resolution limitation of the SuperView-1 satellite image,the interpretation of point like small ground objects was weaker than that of aerial images with high ground resolution.At the same time,mapping personnel have found that there is a small vertical disparity in the stereo image for high-altitude areas,which may affect the comfort and elevation accuracy of human eye interpretation.The conclusion of the study is that,when aerial images cannot be quickly obtained,SuperView-1 satellite images can serve as an effective data source supplement,with accuracy meeting the requirements of railway mapping,but its precision verification needs to be strengthened.