%A
%T Space Shading Algorithm for On-orbit Spacecraft
%0 Journal Article
%D 2009
%J Science & Technology Review
%R
%P 36-39
%V 27
%N 0916
%U {http://www.kjdb.org/CN/abstract/article_254.shtml}
%8 2009-08-28
%X Space shading algorithm for spacecraft is the key link of Meteoroid and Orbital Debris(M/OD) risk assessment. The analysis precision of M/OD risk assessment is mostly dependent on the accuracy of space shading algorithm. The M/OD risk assessment plays a very important role in shielding design and in-orbit safety for spacecraft. For the spacecraft shading problem in orbital debris risk assessment, based on Roberts algorithm and Z-buffer algorithm, a shading algorithm is proposed, which is simple in computation, accurate in results and versatile in applications. Spacecraft structures are often very complex, therefore, in the algorithm, a decomposition of the structure and a related shading are made before a combination operation. The shading of simple spacecraft specified by IADC is analyzed. The exposed areas of spacecraft and each finite element in different yawing directions are obtained. The exposed area of the simple spacecraft is different in different directions. The minimum and maximum exposed areas after shading are 38.91% and 55.27% of the exposed area of the simple spacecraft before shading, which shows that the exposed area of spacecraft has great different in different flight attitude. And changes in spacecraft mission operations, flight rules, and flight planning can reduce meteoroid and debris risks.