Short-voyage low-overload reentry track design method

Abstract

The invention discloses a short-voyage low-overload reentry track design method. In considering of the reentry process of an aircraft reentering the atmosphere at the velocity close to the second cosmic velocity, the concept of gliding type reentry of a spacecraft with a large lift-drag ratio is introduced. The method comprises the steps that firstly, constant roll angle flying at an initial descending section is set, and track parameters are introduced at the gliding section and the tail end to describe the track; and then a needed control instruction is obtained according to the relation ofthe track parameters and the roll angel in a control instruction. Overload limiting is introduced to achieve low overload, and when overload exceeds a certain range, the requirement that overload doesnot exceed the maximum limitation is ensured by properly reducing the roll angle; and finally, different voltage task demands are met by correcting the roll angle of the initial descending section.

Description

technical field [0001] The invention relates to trajectory planning technology, which belongs to the field of aircraft re-entry guidance, and can be applied to the guidance strategy of a re-entry spacecraft with a small lift-to-drag ratio during re-entry into the atmosphere. It has certain reference value for the emergency return process of the existing manned spacecraft. Background technique [0002] The lunar probe returner re-enters the atmosphere at the second cosmic speed and faces severe thermal constraints. For the manned returner, the corresponding overload constraints and landing point accuracy requirements are higher. The existing reentry methods of the earth's atmosphere mainly include ballistic reentry, ballistic-lift reentry, and lift reentry. For the manned lunar exploration return vehicle, the return process is mainly realized by the jumping reentry method in the ballistic-lift type. Under the action of the lift force, it rushes out of the atmosphere again, a...

AI Technical Summary

Problems solved by technology

By jumping re-entry, the designable voyage range of the spacecraft re-entry can be widened, and the maximum re-entry overload and heat flow can be reduced. However, for emergencies that require rapid return with a short voyage, the re-entry time is long and the total heat absorption is large. The problem

Although the existing emergency return method of ballistic reentry is relatively simple, there is a problem that the reentry overload is relatively large, which may reach 7-13g, and the landing points of the return capsule are scattered widely.

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