Small celestial body attachment trajectory self-adaptive curvature matching guidance method

Abstract

The invention discloses a small celestial body attachment trajectory self-adaptive curvature matching guidance method and belongs to the technical field of deep space exploration. The implementation method comprises the steps that: a satellite-borne computer calculates the horizontal distance between an attachment device and a preset landing point according to the measured current position information of a lander, and calculates the safety elevation under the current horizontal distance; the safety elevation is compared with measured actual elevation information, and whether a front movement track conflicts with a terrain obstacle or not is judged; when relative height is in a safe range, the relationship between the shape of the track and the state quantity of the lander is analyzed, a three-axis thrust coefficient is introduced, so that an analytical optimal guidance law with parameters can be obtained through derivation, and a condition of mutual conversion between an analytical energy optimal guidance law and the analytical optimal guidance law with parameters is established; a thrust parameter is adjusted according to the condition, so that the curvature of the track can be improved, so that the terrain obstacle can be avoided; the thrust parameter is restored when the relative height is reset to an expected range; and circular judgment is performed until the value of estimated remaining time tends to be zero, so that the successful landing of the lander is realized.

Description

technical field [0001] The invention relates to a small celestial body attachment guidance method, in particular to a terrain obstacle avoidance guidance method in the final landing stage of a lander, and belongs to the technical field of deep space exploration. Background technique [0002] Small celestial body attachment detection is a hot field in the current deep space exploration technology research, and it is a necessary means to implement asteroid and comet sampling and return missions, and to obtain high-resolution surface images and high-precision topographic and geomorphic data. The key to the safe landing of the attacher on the surface of a small celestial body lies in the accurate "double zero control", that is, the position error between the actual attachment point and the predetermined attachment point is close to zero, and at the same time, the relative velocity of the end of the attacher is close to zero. In the small celestial body attachment tasks that have...

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Problems solved by technology

[0003] The technical problem to be solved by the small celestial body attachment trajectory adaptive curvature matching guidance method disclosed in the present invention is: to realize the small celestial body attachment obstacle avoidance guidance based on the small celestial body attachment trajectory adaptive curvature matching guidance, which has the following advantages: Adaptive adjustment function, by adjusting the curvature of the trajectory in real time, changing the shape of the trajectory, effectively avoiding unexpected terrain obstacles, and improving the safety of attachment; (2) The guidance law adopted is an analytical form, with fast calculation speed and strong autonomy; (3) The guidance law is based on the deformation of the energy-optimized guidance law, which has strong fuel economy

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