Re: Mars Rover Windshield Wiper

Derek Lyons wrote:
Because we don't have a battery that can hold sufficient charge across
the winter

Geez, the poster said POWER DOWN the unit. There is thus no need to have power available throughout the winter (except perhaps just a clock).

And there is that newphangled thing called flash memory that can hold the data even withough power. Shirley they can make RAD versions for space travel. Or does NASA insist on using 1960s technology even for ships they design today ?


and because it's awfully hard to design electronics that
will power down into a deterministic state that will power up reliably
when the solar panels are illuminated again in the spring.

Ahh, typical NASA "can't be done" explanation. Consider the millions of people who turn off their computers at night by just flicking the switch, and turn it back on the next morning by again just flicking the switch ?

Consider that even residential UPS systems are able to warn a computer when power is getting low so that the computer can shutdown. (and I strongly suspect that the rovers already have that built-in).


Then there
is the (AIUI) high probability of damage caused by differential
contraction as the lander cools.


Aren't these ships designed to widthstand even greater temperature ranges during the space travel portion of their journey ?
.

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