A small celestial body landing constant thrust trajectory tracking control method

Abstract

The invention discloses a small celestial body landing fixed thrust trajectory tracking control method, and belongs to the technical field of deep space exploration. The realization method of small celestial body landing fixed thrust trajectory tracking control method includes the steps that landing nominal trajectories realizing a terminal position and velocity constraints are preset based on polynomial acceleration; the velocity increment needed at the current time is calculated according to the difference between the actual trajectories of a detector at the current time and the landing nominal trajectories; and the start-up time of thrust engines in all directions is calculated according to the engine thrust magnitude and the speed increment at the current moment, and the control force of the corresponding time is applied in a single control cycle to obtain the needed speed increment, so that the tracking control of the detector over the nominal trajectory in the single control cycle is realized. The fixed thrust control method is used in each control cycle to achieve the trace tracking control of the detector over the nominal trajectories in the corresponding single control cycle, after a plurality of control cycle tracking controls are completed, a lander is enabled to be from a fly-around orbit to a target sampling point, and when the lander reaches the target sampling point, the speed of the lander meets the constraints given by a task.

Description

technical field [0001] The invention relates to a fixed-thrust trajectory control method for landing a small celestial body, and belongs to the technical field of deep space exploration. Background technique [0002] Small celestial body landing sampling missions have high scientific returns and are currently the main form of small celestial body detection. It is the core technology to complete the detection mission to control the detector to fly around the orbit of the small celestial body to reach the target sampling point predetermined by the mission. In order to ensure the reliability of the control process, a fixed-thrust engine with relatively simple working principle and strong reliability is usually used to realize trajectory control during the landing process of small objects. However, the landing mission requires that the detector can reach the target sampling point accurately, and there are also certain requirements for the speed value when reaching the target sa...

AI Technical Summary

Problems solved by technology

The invention can provide technical support and reference for small celestial body landing sampling tasks, and solve related engineering problems

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