Abstract
Abstract. With the development of space technology, more and more lunar researches are performed by different countries. For the lunar landing mission success, the lunar landing module should equip with advanced Positioning and Orientation System (POS) for the navigation requirements. For the pinpoint landing mission formulated by NASA, a good POS with error less than 100 meters is needed in order to make the lunar module land safely at the exact destination on lunar surface. However, the existing technologies for lunar navigation, such as satellite positioning and star tracker, have poor performance for the navigation requirements. The visual-based positioning technology is an alternative way to make sure a lunar landing module reaches the destination. There are two types of visual-based positioning technology, absolute and relative navigation. The relative navigation system can provide the solution at a higher rate, but the error would accumulate over time. On the contrary, the absolute navigation could provide an initial position or updates of position and attitude for relative navigation. Thus, the integrated navigation system from those two methods can take advantage of both stand-alone systems. On the other hand, the Inertial Navigation System (INS) can help it overcome the disadvantage that the images much closer to the lunar surface are not available. This study shows an integrated navigation system that integrates a visual-based navigation system and an INS, which is implemented in a simulated lunar surface.
Highlights
The moon is the closest celestial body to the Earth
This research assumes that when the time is less than 60 seconds, the Photogrammetry Space Resection (PSR), Direct Sparse Odometry (DSO), and Inertial Navigation System (INS) in the system are working at the same time; when the time is between 60 and 150 seconds, the PSR cannot operate, leaving the DSO to assist the INS algorithm; when the time is more than 150 seconds, the visual navigation algorithms is invalid, and only the INS operates independently
It can be observed that the time is about 60 seconds when the PSR algorithm stops at about 6 km high, and the time is about 150 seconds when the DSO algorithm stops at about 2 km high
Summary
The moon is the closest celestial body to the Earth. How to land on lunar surface safely is an important issue. Advanced positioning and navigation technology are required to land on target precisely. Traditional inertial navigation integrates the angular increment and velocity increment of the IMU to obtain the position and the attitude. The error would accumulate due to the initial error, measurement deviation and noise, even can reach kilometers. Since satellite positioning system is not yet complete on the lunar environment, visual-based navigation technology, which has high autonomy and accuracy for positioning, is an alternative way for navigation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
