The DLR Autonomous Navigation Experiment with the IDEFIX Rover: Software Architecture, Autonomous Navigation Features and Preliminary Operations Concept

The Japan Aerospace Exploration Agency (JAXA) is set to launch the Martian Moons eXploration (MMX) mission in 2026. This sample-return mission aims to enhance our understanding of the origins of Mars' two moons, Phobos and Deimos. In early 2029 (timeline might change), the mission will deploy a small rover named IDEFIX onto Phobos to scout potential sample collection sites for the lander and to conduct additional scientific measurements. IDEFIX is a collaborative development by the German Aerospace Center (DLR) and the Centre National d'Etudes Spatiales (CNES). If successful, IDE-FIX will be the world's first lander on Phobos and the first rover to navigate on Phobos. The rover mission poses several challenges, including a brief four-month operational period, extremely challenging temperatures, significant communication delays, limited data bandwidth, low energy resources, and a yet partially unknown environment. As a technology demonstration and also to assist safe driving, DLR is developing an autonomous navigation onboard module for the rover. This paper outlines the features and architecture of the DLR navigation module, detailing its adaptation to the mission's constraints. Additionally, the paper discusses the testing of the navigation module in both simulated and real test environments as well as the preliminary integration of the module into mission operations.