ESA GNC Conference Papers Repository

Over the last years, the requirements for planetary landing precision have become more stringent as the missions were getting more ambitious. That’s why new techniques need to be investigated and evaluated on a variety of test cases. This paper presents three different techniques developed to estimate the absolute position of a spacecraft along its orbit –or descent- over a celestial body, with a focus on the Moon and Mars. These techniques are based on the recognition of some visual patterns on the surface of the body, and their objective is to update a navigation filter that estimates the state of a spacecraft from a variety of navigation sensors. This document details the different ways that have been explored to achieve this task, and their performances evaluated both on simulated and real test cases, for Mars and the Moon. Finally, the impact on navigation precision is discussed, and the different results prove the feasibility of using such techniques in an onboard calculator for pinpoint planetary landing.