火箭飞行中天球系到星敏系的姿态转换方法

在远程火箭飞行过程中，通过计算天球系到星敏系的旋转四元数，可作为星图模拟的输入数据。本文从坐标系定义出发，首先，完善了基于北京时间的格林尼治恒星时角在工程上的实用算法，根据多次旋转原理，给出了天球系到发射惯性系的姿态转换方法；其次，探讨了发射惯性系到箭体系以及箭体系到星敏系的姿态转换方法；最后，给出算例，通过仿真计算得出结果，验证了方法的可行性。该方法容易理解，根据推导思路也可举一反三，对于星图模拟中姿态的转换具有一定参考意义。

Attitude conversion method from celestial coordinate system to star sensitive coordinate system during rocket flight

During the long range rocket flight, the rotation quaternion from the celestial system to the star sensitive coordinate system can be used as the input data for star map simulation. In this paper, starting from the definition of coordinate system, firstly, the practical engineering algorithm of Greenwhich Star Time Angle based on Beijing Time is improved. According to the principle of multiple rotations, the attitude conversion method from the celestial coordinate system to the launch inertial coordinate system is given; Secondly, the attitude conversion methods from the launch inertial coordinate system to the body coordinate system and from the body coordinate system to the star sensitive coordinate system are discussed; Finally, an example is given to verify the feasibility of the method. This method is easy to understand and can also be used to infer other cases according to derivation idea, which has certain reference significance of the attitude conversion in star map simulation.