The following subjects necessary for lunar soft landing orbit design are reviewed: (1) methods to solve minimum fuel consumption problems; (2) lunar soft landing orbit design based on the results of the fuel consumption problems; and (3) future problems. The answer to the minimum fuel consumption by Pontryagin's maximum principle are presented. Lunar soft landing orbit design using a spherical model are presented for four assumed cases. Powered descending time-altitude profile, transient angle-altitude profile, powered descending time-vertical speed profile, powered descending time-control angle profile, and powered descending time-speed profile in down-range direction are showed. The following has become clear: (1) when powered descent begins from an elliptical orbit, starting from the perigee point is advantageous if the speed increase necessary for landing is employed as the criteria; and (2) constant thrust acceleration level exists to minimize necessary speed increase.
Tsuki Nanchakuriku Kidou Sekkei (Lunar Soft Landing Orbit Design)
1991
21 pages
Report
Keine Angabe
Englisch
Extraterrestrial Exploration , Spacecraft Trajectories & Flight Mechanics , Flight optimization , Lunar landing , Orbit calculation , Soft landing , Orbital mechanics , Descent trajectories , Equations of motion , Interplanetary trajectories , Landing simulation , Lunar exploration , Lunar landing modules , Lunar orbits , Lunar probes , Pontryagin principle , Foreign technology