Research On Navigation Technology Of Astronaut On Moon Surface Based On The Knowledge

When the astronaut is going to perform the extra vehicular activities(EVA)on the lunar surface,obviously,a reliable and accurate navigation system is needed.Since the environment of the lunar surface is much different from the earth's surface,the astronaut may easily get spatial orientation for the microgravity,the absence of the visual reference and other causes.Under these circumstances,the astronaut may have a wrong judgement of the position and orientation,and it is necessary to provide the astronaut with an assistant navigation devices in order to locate themselves accurately on the lunar surface.Under these circumstances,this paper studies a wearable astronaut lunar surface locating system,which selects the inertial component as the main sensor.Firstly,this article analyzes the environmental characteristics of the moon's surface.As a result,the inertial navigation technology is selected as the main navigation method.So the inertial navigation model was further deduced based on the lunar surface environment.According to the characteristics of the astronauts walking process,the navigation model can be simplified.Due to the presence of inertial device errors,individual inertial navigation errors accumulate quickly,so effective error correction methods is needed.Taking into account of the environmental constraints of the moon's surface,this paper combines the prior knowledge of the astronaut with the navigation system.by analyzing the customary regulation of the astronauts' normal walking on lunar surface,the characteristics of the stationary time period when the astronaut's foot contact with the moon's surface can be used.Through the static interval detection,a zero velocity update(ZUPT)correction algorithm is used to suppress and correct the error divergence of the inertial navigation.At the same time,in order to eliminate the astronaut navigation heading errors,by analyzing the behavioral features of the astronaut walking,this paper researched more knowledge which can be used in the navigation system.For example,for the purpose of using the shortest possible time and energy to approach the target,the astronauts intend to walk in a straight line.And astronaut cannot always be in motion,for the mission of fixed-point sampling and other task requirements,the astronauts will have a short-term in-situ stay during walking.These behaviors are combined with the navigation system in order to constrain the divergence of the heading angle error of the astronaut's lunar surface navigation system,thus improving the performance and accuracy of the navigation system.Finally,the algorithm is tested through walking experiments.