Satellites and other spacecraft, like most machines, have parts that move against one another. Unlike most machines, however, they operate in extremely cold conditions, their power source is often very limited, and lubricating or repairing them are not exactly easy tasks. It is for these reasons that researchers at Spain’s Universidad Carlos III de Madrid (UC3M) are coordinating the three-year MAGDRIVE project – an international effort to create a mechanical transmission with no touching parts, that doesn’t need any lubrication.
There would be several advantages to such a system. For one thing, conventional lubricants freeze solid at the cryogenic temperatures (around -200C/-328F) of outer space. Then, even if they could stay fluid, there’s the whole question of how to reapply them in space – this is a particularly valid point for unmanned spacecraft. Even when lubricated, interlocking moving components ultimately wear each other down, so fixing the spacecraft also becomes an issue.
Finally, there’s the matter of energy efficiency. According to the UC3M researchers, regular transmissions sacrifice over half of their energy simply overcoming friction. A touchless transmission wouldn’t encounter any friction, so presumably would use very little power.
At this early point in the project, all that is being stated regarding how such a transmission would work is that it would involve magnetism. While the goal of MAGDRIVE is to allow spacecraft to operate for years with no maintenance or repairs, the researchers believe that it could also have applications here on Earth, such as in CT and MRI machines.