VISUAL-BASED INTEGRATED NAVIGATION SYSTEM APPLIED TO A SIMULATION OF LUNAR MODULE LANDING

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.

Investigation of the Ballistic Descent Mode for a Maneuverable Lander to the Venus Surface

At present, various projects to continue fundamental investigations of Venus are considered in Russia and abroad. It means that the issue of developing a landing module to reach the surface of the planet becomes topical, as the module might provide access to the regions most attractive in terms of research. We propose to use a landing module of the lifting body type, which, as compared to a ballistic class module, is not unacceptably complicated in terms of design and at the same time features a lift-to-drag ratio adequate for solving manoeuvring problems arising in the process of descent into the Venusian atmosphere to reach the target landing area. We consider potential descent trajectories available to a landing module of this type, including the possibility of performing a maximum lateral manoeuvre; we took into consideration its long-period trajectories characterised by multiple re-entries into the dense atmosphere and compared these trajectories to the descent trajectory of a conventional ballistic class landing module. We show that using a manoeuvrable craft expands the selection of potential landing regions, as well as reduces loads and broadens the scope of scientific problems to be solved and studies to be undertaken