Proceedings Article | 23 November 2024
KEYWORDS: Calibration, Satellites, Satellite imaging, Error analysis, Image processing, Cameras, Data modeling, Imaging systems, Geometrical optics, Motion models
Rotating imaging optical satellites use the mode of cone scanning + area array to achieve high-temporal coverage of large areas, and the whole imaging process involves more loads and platform stand-alone machines, and its motion characteristics are mainly composed of camera load rotation, ground speed (satellite orbital motion + earth rotation), tremor disturbance, etc. The error sources involved in the imaging process mainly include GPS positioning error, pointing measurement mechanism (star sensor, gyroscope, pendulum mirror mechanism, fast reflection compensation mirror, detector rotation mechanism and turntable, etc.), camera load internal error, GPS receiver antenna and camera photography center eccentricity error, various load installation errors, time synchronization errors, etc. On-orbit geometric calibration is the key and basis for optical remote sensing satellite preprocessing. Affected by factors such as changes in the space environment during satellite launch and operation, the on-board payload structure and state will change, which will further lead to a large error between the laboratory calibration parameters and the real parameters after orbit, which will directly affect the accurate processing of image data and subsequent practical applications. Based on the strict geometric imaging model, this paper studies the analysis and calibration method of the full-link error characteristics of rotating ultra-wide optical satellite in motion, breaks through the key technologies such as analysis and simulation of the full-link error characteristics of dynamic imaging, construction of generalized equivalent normalized calibration model, and accurate calculation of error parameters based on step-by-step, so as to lay a foundation for the application of high-precision geometric processing and subsequent image stitching, fusion and classification monitoring of rotating imaging optical satellites.
