Title :
Star recognition algorithm for APS star tracker: oriented triangles
Author :
Rousseau, G. Lamy au ; Bostel, J. ; Mazari, B.
Author_Institution :
Lab. de Recherche Balistique et Aerodynamique, Vernon
Abstract :
An efficient star pattern recognition algorithm is presented. The purpose of this algorithm is to make sure of the compatibility of the software and the imaging sensor noise level. The new CMOS APS sensors have not currently reached the same accuracy as the former CCD sensors in position as well as in magnitude determination, especially in the dynamic stages. This algorithm allows the system to recognize the star pattern 20% faster than with reference algorithms. No false recognition has been noticed. Used databases have a size 5 to 10 times smaller, depending on other reference algorithms. Oriented triangles are used to compare the measured star pattern with the catalogue stars. The triangle´s characterization criteria propose several solutions in a first time. A unique solution is selected by means of identification and validation methods in a second time. First results, presented hereinafter, are very encouraging, and this algorithm may be used in the future APS star trackers. APS star tracker robustness is significantly enhanced by this method during the critical navigation phases
Keywords :
CMOS image sensors; image recognition; space vehicles; APS star tracker; CCD sensors; CMOS APS sensors; catalogue stars; critical navigation phases; identification method; imaging sensor noise level; magnitude determination; oriented triangles; reference algorithms; space vehicle orientation; star pattern; star recognition algorithm; triangle characterization; validation methods; CMOS image sensors; Charge coupled devices; Image sensors; Noise level; Noise robustness; Pattern recognition; Quaternions; Satellites; Sensor arrays; Vehicle dynamics;
Journal_Title :
Aerospace and Electronic Systems Magazine, IEEE
DOI :
10.1109/MAES.2005.1397146
