Characterization of the MMX Rover Locomotion Flight Model for Check-Out and Parameterization

IDEFIX is a four-wheeled 25kg rover that is jointly developed and built by the French Centre National d’Études Spatiales (CNES) and the German Aerospace Center (DLR). It will be brought to the Martian Moon Phobos by the Japan Aerospace Exploration Agency (JAXA) as part of the Martian Moons eXploration (MMX) mission in 2027. IDEFIX’s objectives are to scout the surface, demonstrate driving in milligravity and perform scientific measurements. To upright after landing on the surface, drive and align the rover to the sun, each wheel is mounted on a leg, which can be rotated full 360° in its respective shoulder joint. In previous publications, the development, flight design and qualification of the locomotion subsystem were presented.During the cruise phase there will be several health checks and – once landed on Phobos – the locomotion will be checked-out. To be able to analyze the health state quantitatively and parameterize the system properly, a good characterization of the system is important. The foundation of this characterization are tests and health-checks on the flight model (FM), as well as performance test results on the qualification model (QM). A selection of the post-processing and analysis of this measured data, that was done for the characterization of the Loco FM, is presented in this paper.

1. Introduction

The MMX rover IDEFIX’s overall mission is described in [1], [2] and its scientific goals in more detail in [3]. Figure 1 shows a render of the rover from the robotic simulator (see [4]), which has been used for the design phase of the rover and will also be used in the operations.