5 challenges an electric motor has to overcome on Mars
Outer space is unforgiving. This is why precision drives
embarking on a trip to other planets need to meet extremely high-quality
standards.
Every Mars drive from maxon is based on a catalog product
and is modified for the specific mission. That’s because the DC motors,
gearheads, and encoders face brutal conditions during liftoff, the long journey
through space, and the mission on the Red Planet. In this blog, I will talk
about the properties a drive needs to have to qualify for a journey to Mars.
Outer space is unforgiving. This is why precision drives
embarking on a trip to other planets need to meet extremely high-quality
standards.
Every Mars drive from maxon is based on a catalog product
and is modified for the specific mission. That’s because the DC motors,
gearheads, and encoders face brutal conditions during liftoff, the long journey
through space, and the mission on the Red Planet. In this blog, I will talk
about the properties a drive needs to have to qualify for a journey to Mars.
Vibration and shock
The first challenge is to survive the rocket launch. This
means that the motor must be resistant to shock and vibration. The vibration is
not as strong as people might think: A little more than on a passenger plane,
but not much more, and only for a few minutes. Shocks, on the other hand, are
something that we need to deal with on a regular basis when working with
standard products. These occur mainly during staging, which is when the first
stage separates from the rest of the rocket. The resulting forces would destroy
normal motors because the rotor would become separated from the stator. That’s
why we need to reinforce our drives, for example by encapsulating the rotor and
using special welds, special retaining rings, and optimized materials.
Vacuum and radiation
The trip to Mars takes about six months. During this time,
the drives need to survive the vacuum and radiation. The most damaging
radiation doesn’t come from the Sun, but from high-energy particles from
outside the solar system, which can damage the electronics. That’s why we need
specially hardened electronics for the Hall sensors on the motors. To be extra
safe, we’re installing them in pairs for redundancy. In a vacuum, the
durability of components is important. You can’t use a glue that undergoes
changes in its chemical properties and loses its adhesiveness after a few days
in a vacuum.
Published by maxon on Nov 11, 2020