Double-theodolite measurement system used in the image calibration of space photographic instrument

The purpose of characterizing the image of space photographic instrument is to gain the space included angles from three coordinate axes in the three — dimensional coordinate of the image and the directionality of the three axes of coordinate in the frame of axes of the instrument. The two reference frames will keep in the same direction finally by adjusting according to space angles. This problem was solved by a new high-precision measurement system composed of a double-theodolite and a set of communication system. In the survey system, two TDA5005 total stations from Leica Company will be selected as the double-theodolite and the interdependence of both coordinate systems can be achieved by moving the stations only at one time. Therefore, this measurement system provides a highly efficient and high-precision surveying method to the image calibration of the space photographic instrument. According to the experiment, its measuring accuracy can reach arc-second level.