A deep space landing geometric orbit determination method, system and deep space lander

Abstract

The invention relates to a geometrical orbit and gesture determining method and system for deep space landing and a deep space lander. The method comprises the following steps: firstly, determining adirection vector of the lander relative to the Mars and the distance from the lander to the center of the Mars; solving the height from the lander to the surface of the Mars according to the distancefrom the lander to the center of the Mars and the radius of the Mars; establishing an inertial coordinate system xIyIzI to obtain a gesture matrix from the inertial coordinate system to a body coordinate system; further solving the inertial position and the inertial speed of the lander. According to the method and system, geometrical orbit and gesture determination is carried out by using a distance and speed measuring sensor automatically. Under the circumstance that IMU in a power falling section fails, orbit and gesture determination can be carried out by means of the distance and speed measuring sensor so as to achieve initial standard capturing of autonomous navigation, the dependent degree of the inertial navigation system to the initial standard is alleviated, and the robustness andthe failure tolerant capability of the autonomous navigation system of soft landing are improved. The algorithm is an analytical algorithm which is convenient for on-star algorithm, thereby laying afoundation for implementing a soft landing task successfully.

Description

technical field [0001] The invention relates to a deep space landing geometric orbit determination method, system and deep space lander, which belong to the field of autonomous navigation for Mars and deep space exploration soft landing missions. Background technique [0002] The Entry, Descent, and Landing (EDL) section of the Mars exploration mission is the last 6 or 7 minutes of the Mars probe’s journey of nearly 700 million kilometers. It is the key stage of the Mars surface exploration mission and the most difficult stage. EDL technology is also one of the key technologies for Mars surface exploration missions. From the time the Mars probe entered the Martian atmosphere at a speed of 20,000 kilometers per hour, it went through a series of stages such as atmospheric deceleration, parachute drag, and power deceleration, and finally in order to ensure a safe and accurate landing on the surface of Mars. [0003] Most of the failure cases of Mars exploration are due to the...

AI Technical Summary

Problems solved by technology

Once the attitude loses its reference, the height information calculation error will affect the successful implementation of the mission

The 2016 ESA ExoMars Mars mission lander lost its attitude reference due to the saturation of the IMU, resulting in an altitude calculation error that caused a GNC command execution error, which eventually caused the lander to crash

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