Re: Mars Rover Windshield Wiper

John Doe <jdoe@xxxxxxx> wrote:

John Crichton wrote:
the temperature on Mars can be as low as -220ºF. The differing thermal
expansion coefficients of the component parts will cause mechanical
stresses to set up which will cause breakage of the connections (solder
joints, electric welds, etc.) which will render the electronics useless.


OK, this is a show stopper. Is there research being conducted in
developping electronic components that can , when put together,
widthstand the shrinkage at those winter temperatures ?

You canna' repeal the laws of physics Jim! That's only partly in
jest... But I doubt anyone is doing such research due to the extreme
lack of demand.

has anyone ever tried to cool an inactive circuit board to test actual
temperature at which failures begin due to shrinkage ?

You could do so - but it wouldn't prove much. The temperature at
which damage occurs is going to be highly dependent on the exact
materials used and their exact configuration.

D.
--
Touch-twice life. Eat. Drink. Laugh.

http://derekl1963.livejournal.com/

-Resolved: To be more temperate in my postings.
Oct 5th, 2004 JDL
.

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