MMX Rover: thermal vacuum tests - Copyright: Nicolas DOUMAS - CNES
Thermal vacuum tests of the MMX PFM (Proto Flight Model) rover were successfully completed on March 11 in the CNES thermal lab. They were an important step in the validation of the rover before its delivery to the Japanese Space Agency (JAXA) in summer 2023.
The rover is part of JAXA's Mars Moon eXploration (MMX) mission, whose objectives are to study the two moons of Mars, Phobos and Deimos, and to bring back samples from Phobos. The MMX rover will land on Phobos as a scout for the main mission and drive to study the composition and characteristics of the soil on this Martian moon.
MMX is the first rover entirely designed by CNES. Its architecture is co-designed with the German Space Agency (DLR). CNES is developing the internal module and DLR the structure and locomotion part.
The assembly and tests are carried out by CNES at the Toulouse Space Center. The main environmental tests are thermal vacuum tests, EMC tests and mechanical tests.
The rover's thermal vacuum tests were successfully completed on March 11 after three weeks of intensive effort. These environmental tests are an important step in the validation of the rover with its separation system (MECSS).
The objectives of these tests were multiple:
- To carry out the degassing of the rover to limit contamination
- To validate the functional chains of the on-board system at the extreme hot and cold temperatures to which the rover will be subjected on mission
- To carry out thermal balance phases which will allow to recalibrate the model and to adapt the post-test thermal control
- To carry out the thermal cycles required by JAXA for the qualification of the rover
TVAC rover MMX PFM at the thermal lab - Copyright: Nicolas DOUMAS - CNES
The thermal vacuum tests were carried out in the 2m3 tank of the thermal laboratory. The MMX rover team was able to rely on the laboratory teams and the thermal engineers for the preparation and the implementation of the specific means for this test.
The different test phases allowed to realize all the functional tests planned with in particular the validation of the functioning of the equipment on the hot and cold temperature ranges expected during the cruise but also during the mission on Phobos.
Finally, the thermal environments have been simulated as expected despite the hazards in the functional tests. The thermal balance phases were also successfully carried out, compromises were found between precision and duration, in adequacy with the constraints of the project.
The AIT (Assembly, Integration and Test) activities continue with the integration of the solar generator for the mechanical environment tests, followed by the communication tests between the rover and the Rolbox electronic box (box installed on board the probe). Finally, the final functional tests will complete this series of tests on the rover.
The delivery for JAXA (at MELCO in Kamakura, Japan) is scheduled for this summer, the final sprint is on for the project teams.
These tests could not have been carried out without the strong involvement of all the teams (architect, AIT, project, quality, laboratory and thermal). Around the tests carried out in 3x8 hours, a lot of work was also done to prepare and analyse the test results.
