Development and Qualification of a Modular Drivetrain Unit

Abstract

This paper presents the development and qualification process of DLR's permanent magnet synchronous motor/gear DriveTrain unit (DT38). Based on a plurality of laboratory tests and experiences in space missions like ROKVISS or MASCOT, the unit was further developed and tested for upcoming space missions. The focus of this paper lies in the development of a robust and reliable DT38 unit for space rover, which has to cope with extreme environmental conditions like dusty, sandy terrain, large temperature fluctuations and radiation. Therefore different kind of sealing concepts has been tested. A detailed investigation on space lubrication and optional a special coating on the HD-gear for cold welding prevention shows the potential and the application spectrum of the DT38 units. For the shaker test, a vibration spectrum of a Japanese H3 launcher was selected since this rocket holds one of the highest vibration levels. Due to the fact that the qualification of the DT38 unit is performed on component level, the unit was hard mounted to the shaker. In the field of exploration on other planets, moons or asteroids with space rovers, the information about the surface and there structure is often limited. Therefore the unit went through a tough load- and duration test, to ensure its functionality on uneven surfaces and throughout the entire mission. A vacuum and radiation analysis completes the test series. The paper gives an overview on the results.