一种适用于月球跳跃返回的改进解析预测校正制导律  

An Enhanced Analytical Predictive Corrector Skip Guidance for Lunar Return Vehicles

作　　者：周军[1] 水尊师[1] 葛致磊[1] 

机构地区：[1]西北工业大学精确制导与控制研究所,西安710072

出　　处：《宇航学报》2012年第9期1210-1216,共7页Journal of Astronautics

摘　　要：解析落点预测-校正制导律具有计算量小的特点,适用于月球返回舱机载计算机的在线计算,针对其对远航程适应性差的问题,提出了一种改进的解析预测制导律。通过调整上升段的控制增益,减小返回舱飞离大气层时刻实际状态与标准状态的偏差,对飞出大气层的速度进行修正以补偿弹道段空气阻力引起的航程减小。二次再入段采用数值预测-校正制导,利用逐步校正的方法,解决了收敛问题,避免了复杂的基准弹道设计过程。数值仿真表明,所设计的制导律能够适用于远航程情况,在具有初始位置偏差、质量偏差、气动偏差、大气偏差的情况下,终端位置精度在5km以内,表明该制导律具有良好的鲁棒性,该制导律具有在线实施的潜力。Analytical predictive skip guidance law is suitable for on-line operation of the on-board computer due to its simplicity, but it has poor performance for the long target ranges. An enhanced guidance law is proposed to meet the requirement of long ranges. The main factors affecting the landing accuracy are analyzed. The tracking errors of altitude and velocity between calculated states and actual ones are minished by adjusting the control gain during the ascending phase. The desired velocity exiting the atmosphere is modified to compensate the undershoot range eaused by drag during ballistic phase. The secondary entry makes use of numerical predictor-corrector guidance, and the step by step corrector is applied to solve convergence problem, thus avoiding the complicated reference trajectory design process. The numerical simulation indicates that the proposed algorithm is not sensitive to initial position error, mass error, aerodynamic error, atmospheric dispersion and so on. The landing point deviation is within 5km, so that the guidance law can be implemented onboard when the flight range is long, and offer more flexibility to a mission design team.

关 键 词：再入制导 跳跃再入 预测校正 月球返回 

分 类 号：V412.1[航空宇航科学与技术—航空宇航推进理论与工程] V412.4