变结构空间飞行器发射过程的姿态研究

Study on Attitude of Variable Structure Spacecraft in Launching Process

针对某类空间飞行器在发射过程中产生结构变化的问题,基于多体系统动力学方法建立了变结构空间飞行器动态发射研究模型,进行了理想发射情况下的数值研究,并与地面试验进行了对比分析.分析结果表明,该模型可以准确地描述飞行器的发射运动.引入推力偏心、扭矩偏转和重力梯度3种干扰因素对飞行器发射过程的姿态进行了数值研究.研究结果表明:推力偏心角越大,飞行器相应的姿态角变化越大;扭矩偏转对飞行器的俯仰角和偏航角都有影响,并且扭矩偏转角越大,姿态角变化越大;在小发射角下重力梯度对飞行器的姿态影响不明显.

Aiming at the problem of structural transformation for some spacecraft during launching process,the dynamic launching model of variable spacecraft was developed based on multi-body system dynamics, and a numerical study of ideal launching was carried out. Compared with ground test result, the model can accurately describe the launching motion. The attitude during launching process with three jamming factors of thrust misalignment,torque deflection and gravity gradient was analyzed respectively. The result indicates that corresponding alteration of attitude angle increases with the increase of thrust misalignment angle, both pitch angle and yaw angle are affected by torque deflection, and alteration of attitude angle increases with the increase of deflection angle. The influence of gravity gradient on attitude angle is not obvious under the conditions of small launching angle.