载人登月软着陆制动段最优制导方法(英文)

提出一种解决软着陆制动段燃料最优制导以及闭环控制的方案.首先使用庞氏极大值原理将制动段燃料最优问题转化为一个初值问题,并使用遗传算法搜索求解；其次为了解决最优制导的闭环控制问题,将最优弹道作为标称弹道,使用RCS系统对轨道面内两个方向误差量进行解耦,分别使用极限环控制.仿真表明,所规划出的燃料最优弹道比阿波罗方案能节约159.7 kg的燃料,而闭环控制系统可以将初始1 000 m的位置误差和5 m/s的速度误差收敛到接近段入口误差要求以内,在闭环控制过程中,燃料消耗不大于87.75 kg,总体燃料消耗节约至少71.95 kg.

Optimal Guidance Law for Braking Phase of Manned Lunar Soft Landing

A detailed study of the guidance law for braking phase has been carried out to find the fuel-optimal trajectory and the closed-loop tracking strategy.First, the problem of optimal guidance is transformed into an initial value problem by Pontryagin’s maximum principle and then is solved by Genetic Algorithm(GA) searching.Second,as the optimal guidance law cannot be applied online,the non-linear control law based on the limit cycle is proposed to track the optimal trajectory.Simulations show that the fuel consumption of optimal guidance law is less than traditional way by 159.7 kg,and the closed-loop control is very effective in tracking the optimal trajectory,which can converge the error from 1000m and 5m/s to 100m and 1m/s,respectively,with fuel consumption of 87.75 kg at most.Thus the fuel is saved at least 71.95 kg comparing with the traditional guidance law in total.