Abstract
The invention discloses an intelligent power dropping track online planning method. The intelligent power dropping track online planning method includes the following steps: firstly, judging whether the condition that propellants are in short supply or the condition that postures are continuously out of the tolerance due to the fact that disturbance torque generated by a main engine is larger than control torque occurs in a main speed reduction stage or not, if the condition that the propellants are in short supply or the condition that the postures are continuously out of the tolerance due to the fact that the disturbance torque generated by the main engine is larger than the control torque occurs, directly starting a hovering stage by adopting a track online planning strategy of thrusting switching, guide law resetting and a mode switching sequence, and otherwise, enabling track planning not to be carried out; secondly, judging whether a rapid adjustment stage is out of the height tolerance or not, if the rapid adjustment stage is out of the height tolerance, calling a safe mode guide law, changing a target state into a hovering state, and otherwise enabling the track planning not to be carried out; thirdly, judging whether an approaching stage is out of the height tolerance or speed tolerance or not, if the approaching stage is out of the height tolerance or speed tolerance, re-planning a guide target of the approaching stage, calling the safe mode guide law, directly starting the hovering stage, and otherwise, enabling the track planning not to be carried out; finally, judging whether the condition that the propellants are in short supply occurs in the hovering stage or not, if the condition that the propellants are in short supply occurs in the hovering stage, re-planning an obstacle evading track and a slow dropping track to shorten dropping time, and otherwise enabling the track planning not to be carried out.
Description
technical field
[0001] The invention relates to an online planning method for an intelligent power descent trajectory, which is mainly applied to deep space landing probes and belongs to the technical field of spacecraft guidance, navigation and control. Background technique
[0002] The power descent process of a deep-space celestial body’s soft landing can generally be divided into six task sections: 1) The main deceleration section: the height from the surface of the celestial body is from about 15km to about 3km. The main task of this section is to brake for soft landing and reduce the speed of the lander. To the preset value, the altitude drops to about 3km. 2) Rapid adjustment section: the height from the surface of the celestial body is from about 3km to about 2.4km. The main task of this section is to quickly connect the main deceleration and the approach section. 3) Approach section: The height from the surface of the celestial body is from about 2.4km to about 100...
