一种提高轨道精度的改进姿态控制技术

A New Attitude Control Approach to Improve Trajectory Accuracy

摘要:

针对我国长征系列火箭普遍存在的残骸落点普遍较理论落点靠前的现象,开展多次飞行数据的比较,结果发现一级上升段内火箭的飞行速度、位置与设计预示值之间的偏差存在极性稳定、幅值增加增大的特点,尤其是Y向速度偏差甚至超过5%,远大于预期值;本文针对该现象开展机理分析,最终确认现在长征系列火箭普遍采用的“姿态角偏差+角速度”控制方案对程序角持续变化的工况存在幅值及极性较为稳定的静差,该角偏差持续作用下,将导致X向和Y向速度及位置偏差;针对该机理,探索、比较潜在的解决措施,最终确定采用实现简便、控制效果好的“姿态角偏差+角速度偏差”双偏差姿态控制方案;仿真结果表明,双偏差姿态控制方案能显著提高助残骸落点精度及段轨道精度、降低气动载荷,有利于火箭飞行品质的提升。

Abstract:

For explaining the reason of China’s long march series of rocket wreckage landing point is in front of the expected one,through comparing many times flight data , we find during the first ascending stage,the flight position and velocity are systemic different from the normal trajectory data,especially the error or Vy even exceeding 5%,which is not acceptable during the design period.And finally we assure the mechanism behind the phenomenon is the attitude control law of “attitude angle deviation+ attitude rate”,which is widely used by Long March rockets.After comparing several potential ways,the “double deviation attitude control scheme” of “attitude angle deviation+ attitude rate deviation” is selected,which can significantly improve the precision of trajectory accuracy and wreckage landing accuracy, reduce the aerodynamic load, improving the quality of the rocket flight.