Sung-Ho Rhee/ Joon Lyou
International Journal of Aeronautical and Space Sicences, vol. 13, no. 2, pp.260-265, 2012

Abstract : We have developed satellite devices for fine attitude control of the Science & Technology Satellite-2 (STSAT-2). From the mission requirements of STSAT-2, the conventional analog-type sun sensors turned out not adequate, and a compact, fast and fine digital sun sensor (FDSS) was motivated. The FDSS use a CMOS image sensor and has an accuracy of less than 0.03degrees, an update rate of 5Hz and a weight of less than 800g. A pinhole-type aperture is substituted for the optical lens to minimize the weight. The target process speed is obtained by utilizing the Field Programmable Gate Array (FPGA) in acquiring images from the CMOS sensor, and storing and processing the data. The sensor accuracy is maintained by a rigorous centroid algorithm. This paper describes the FDSS designs, realizations, tests and calibration results.

Keyword : STSAT-2, FDSS, CMOS-image sensor(CIS), Pinhole-type aperture,Centroid algorithm