METHOD FOR DIRECTLY PLANNING REENTRY TRAJECTORY IN ALTITUDE-VELOCITY PROFILE

摘要

A method for directly planning a reentry trajectory in an altitude-velocity profile comprises the following steps: S1, extracting actual operation parameters of an aircraft, configuring, according to a task requirement, a stagnation point heat flux maximum (I), a dynamic pressure maximum q_max, and an overload maximum n_max, and solving for an altitude-velocity boundary of a reentry trajectory, that is, a lower boundary of the reentry trajectory in an altitude-velocity profile; S2, finding, according to a reentry motion differential equation, the reentry trajectory in an initial descent phase, and determining a start point of a glide phase according to the trajectory in the initial descent phase; and S3, planning, on the basis of the lower boundary of the altitude-velocity profile, a trajectory in the altitude-velocity profile that meets a constraint of a terminal, calculating a corresponding angle of inclination, and obtaining the reentry trajectory. The present method enables accurate planning of a reentry trajectory, and eliminates risks of generating a reentry trajectory that does not meet a process constraint due to lack of consideration of a flight path angle and a change rate thereof, thereby improving reliability of reentry trajectories, achieving fast computation, and providing high solution accuracy.