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A method for determining laser pointing of spaceborne laser rangefinder and error analysis

The laser rangefinder and the mapping camera have strong complementarity in the positioning of the ground target, and the combination of the two can obtain a better three-dimensional positioning accuracy of the ground target.In order to achieve highly accurate positioning of ground targets, meet the needs of large-scale surveying and mapping, and provide the required elevation control points for the stereo surveying and mapping camera, it is necessary to accurately measure the position of the laser footprint.A method for determining the position of the laser footprint based on a footprint camera is proposed. First, a low-resolution footprint camera is used to directly record the laser emission direction, and then the low-resolution footprint camera is recorded by a method based on image feature point matching. The position of the laser footprint is matched to the image of the high-resolution stereo surveying and mapping camera, and finally the direction of the emitted laser is accurately determined. This method is not related to the attitude determination error of the laser rangefinder and the internal orientation element determination of the footprint camera. Through error analysis, it can meet the 1:10 000 scale positioning accuracy requirement.