A Shadow Map Approach to Calculate Cross Section Area of Spacecraft

The atmospheric drug must be fully taken into account for accuracy orbit determining of spacecraft below 500 km. In this paper, a computer graphical approach based on the fundamental idea of shadow map is proposed to accurately calculate the cross section area of spacecraft. Firstly, the complex geometry surface of spacecraft is represented in the form of triangle grids, and the relative motion among spacecraft components is considered. Secondly, the shadow map algorithm is employed to project the spacecraft model onto a shadow plane, and then the cross section area can be found out by analysis the amount of shadow pixels in the shadow graph. The simulation and experiments are given to validate the proposed method and the results indicate that this method can deal with complex spacecrafts whose components have relative motion.