30 results about "Atmospheric entry" patented technology

The invention relates to an atmosphere entry guidance method using a parachute-opening height as a control target. The atmosphere entry guidance method comprises: (1) completing nominal trajectory design to obtain nominal guidance law uref, nominal longitudinal range sref, nominal height change rate h<.>ref, nominal resistance acceleration Dref, nominal lift force acceleration Lref, nominal to-be-flying height Htogo_ref and nominal flight path angle [gamma]ref; (2) according to the deviation of the current flight longitudinal range s, the current resistance D and the current height change rateh<.> relative to the nominal longitudinal range sref, the nominal resistance acceleration Dref and the nominal height change rate h<.>ref, and the nominal to-be-flying height Htogo_ref correspondingto the current speed, predicting the current to-be-flying height Htogo_p; (3) according to the predicted to-be-flying height Htogo_p, calculating a control compensation amount [delta]u to eliminate the deviation between the predicted to-be-flying height and the reference to-be-flying height; (4) determining the final guidance law uc by using the guidance law compensation amount [delta]u and the nominal guidance law uref obtained in the step (1); and (5) real-timely obtaining the longitudinal range s, the height change rate h<.> and the resistance acceleration D of a landing device from an atmosphere entry point to parachute-opening, generating guidance law uc, and transmitting to a landing patrol device so as to carry out closed-loop control.

The invention discloses a self-adaptive planning method for an atmosphere entrance guidance trajectory. The method comprises the following steps: (1) acquiring a change rule of a flight longitudinal range and a cross range along with a heeling angle; (2) sectioning a whole entrance process, and determining a guidance law of each stage; (3) setting different entrance point initial longitudinal ranges, judging whether parachute-opening states in different entrance points satisfy given constraints, if so, positively increasing the initial longitudinal range or negatively decreasing the initial cross range, until a certain constraint is not satisfied, and determining a limit range of the initial longitudinal range which can be adjusted by the above guidance law; (4) in a actual flight process,judging whether the initial entrance point longitudinal range is within the above limit range, if so, using the guidance law in the step (2) to control; if not, executing the step (5); and (5) calculating a deviation value of the actual initial longitudinal range exceeding the limit range, correcting a longitudinal range reference value of a reference ground track, and substituting a corrected value into the guidance law in the step (2), to obtain a new guidance law, and using the new guidance law to control.

The invention provides an anti-interference composite online guidance method for the atmospheric entry section of a Mars lander. The guidance method comprises the following steps: a. Building a dynamic model of the atmospheric entry section of the Mars lander; introducing the dynamic model of the atmospheric entry section of the Mars lander Mars atmospheric density uncertainty interference; b, construction interference observer, the interference observer estimates the Mars atmospheric uncertainty interference; c, design prediction-correction guidance law, the prediction-correction guidance law The undetermined parameters of the roll angle magnitude are updated; d, the interference observer described in step b is compounded with the prediction-correction guidance law described in step c to obtain the anti-jamming composite guidance law; the anti-jamming composite guidance law The Martian atmospheric uncertainty disturbance is compensated by the estimation of the Martian atmospheric uncertainty disturbance.