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As I understand it most electronic components on things sent to the moon or Mars are kept in a WEB (warm electronics box) to keep them in a optimal working environment, to prevent degradation of said components.

But I have not found anything about electronic motors, and if there are any similar considerations that need to be taken into account for them as well.

Do electric motors on things such as the Curiosity rover drive wheels have heaters? And are the motors for say a hand drill built for a mission to Mars any differently then a hand drill on earth?

In short: Can I drive a Tesla model S or use my Dewalt hand drill on Mars?

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  • $\begingroup$ If the motor electronics is also in the WEB, the electric motor needs no heaters. But the motor should not get too hot. Cooling the motor with air is possible only on Earth, but not on Mars. $\endgroup$ – Uwe Feb 12 '18 at 20:24
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Yes, the motors all have heaters. A fair bit of the energy budget per day on the MER rovers (now MER rover) goes into preheating the motors. You can reduce the energy required by waiting until the afternoon, so they get some natural heating after the overnight cold soak. But you still need heating.

There was an attempt to develop motors for Curiosity that used a dry lube and could operate at much lower temperature. However that development didn't pan out, and the Curiosity motors also need to be preheated before use.

The motors are built using the same approaches as the brushed (MER) and brushless (Curiosity) motors used on Earth, though there is special attention to the gearboxes to keep out dust and have long life.

As for your Tesla Model S on Mars, even harder than pre-heating the motors would be pre-heating the battery. The energy required would be huge due to the mass of the battery. Also you'd be in a bit of a pickle trying to warm the battery with energy that you can't get from the battery because it's so cold.

Your DeWalt hand drill might work if you preheat it and you have a power source for it. Though you may need to worry about heat dissipation if it's under load, e.g. drilling something tough, since the convective cooling in the thin Martian atmosphere will be negligible.

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  • $\begingroup$ What part of the motors have heaters, the electronics, the gearbox? The windings produce heat when used. $\endgroup$ – Uwe Feb 13 '18 at 9:51
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    $\begingroup$ The whole thing gets heated. There is lubrication in both the gearbox and the motor that needs to be fluid. $\endgroup$ – Mark Adler Feb 13 '18 at 18:09
  • $\begingroup$ Wouldnt it be usefull to have the battery also be in the WEB with the other electronics? $\endgroup$ – Down2earthspacenut Feb 15 '18 at 23:51
  • $\begingroup$ It is.......... $\endgroup$ – Mark Adler Feb 16 '18 at 1:40
  • $\begingroup$ Interesting tidbit: Since the Curiosity motors were going to have dry lube and not need heating, they were not designed with space for the heaters internally. When the dry lube didn't work out and heaters had to be added, they couldn't redesign the motor cases to make room for internal heaters. That's why the motors have external heaters which require a long preheat time compared to internal heaters. $\endgroup$ – Wayne Conrad Sep 5 '18 at 21:04

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