Something to ponder....

[ECSI]

I saw the following on a gspec newsletter...it got me to wondering:

[Ken Moore]

Quick guess: Forgot to consider zero gravity.

[ECSI]

LOL...I don't have the answer yet, it comes out in next weeks newsletter. I am assuming though that its not as simple as someone at a space lab just forgetting about zero gravity. Also, its a month after the launch that the boss gets angry.

[Smoke]

I am going take a guess at it. I think it will have something to do with the magnetic field and a motor with brushes.

[panic mode]

They didn't sing to it like you do...? Was the spacecraft still in orbit or returned from mission on that "one month later"? Did they crash or burn on re-entry? Person trained on it reported sick and new guys are not familiar with it? Someone glued "MOVE" button with gum or crazy glue? They moved licence to another PC? Was that Siemens setup or maybe they installed new version of RSLinx that doesn't work with RSNetWorx for DeviceNet? The mission was complete, spacecraft landed fine, but the fuel and batteries ware wasted and janitor unplugged the power cord to use outlet for the vacuum cleaner? The mission was complete, spacecraft landed fine, but cheerful crawd pulled the cord which was trip hazard anyway? You are fired and boss is just trying to prepare you because he can't stand you crying, hugging his legs and not wanting to leave? He was just checking if you have nervs of steel for next even bigger mission?

[Nathan]

Smoke, ya beat me to it! Got that zero cross product goin' on....motor needs a push...shoulda used 3 phase... or maybe it was RSpowered... (Panic's on to something big ) That's a great e-newsletter idea, btw...I think I'm gonna have to "borrow" the concept.... Edited November 2, 2006 by Nathan

[Smoke]

I love this one You could do the top ten for Letterman Edited November 2, 2006 by Smoke

[Crossbow]

Actually I think the box and Panic may be on two different planets...

[TimWilborne]

He gets my vote for creativity. The solution that will be posted better be good, otherwise we will have to send Panic off for evaluation Oh I meant send Panic's solution off for evaluation

[JesperMP]

Can it be this: On the earth the magnets in the DC motor are in a weak static magnetic field (eaths north-south magnetic field). In space the same magnets will be passing through the same magnetic field many times. The polarity will change north-south - south-north as the spacecraft travels around the globe. The changing magnetic field will cause a slow demagnetisation. Edited November 3, 2006 by JesperMP

[panic mode]

the way i see it this article is a joke, there could be million things that went wrong and there is not enough information to start with but the only component mentioned is classic DC motor and one has to guess what could go wrong. person who witnessed lunch of his "baby" will know if that baby is still in space or landed (makes huge difference). sure motors can and do fail but i would expect that person involved in design was a bit more familiar with the system than what we can get out of that article. i guess if the craft is still in orbit circling planet some 4-5 times per day, after 30 days of travel, potential number of seen planet's pole changes would be sufficient to demagnetize it if the field was strong enough. i don't think planet's magnetic field is nearly strong enough. I may have seen once or twice permanent magnets and those used in motors are no joke. they do not get demagnetized by local magnetic field (such as that from rotor coils). to demagnetize permanent magnets used in traditional DC motor one needs lots of heat (motor melted) or magnetic field strong enough and changing oftne enough to give that spacecraft boost big enough to send it to a different planet (and probably one out if our solar system). and demagnetizing doesn't happen on a finger snap after one month, it is gradual process. i am sure that once in orbit they do series of system checks periodically. motor growing weaker would be easily detected (longer time to actuate). there is bunch of other factors such as cosmic radiation which degrades all components (need shielding and careful selection of suitable materials) including wire and comutator insulation, electronics used to drive it etc. Cosmic radiation, temperature and pressure changes, planets magnetic field, accel and decel, vibrations, material selection etc are such obvious elements to take into account that none of this could go through rigorous testing with flying colors unless everyone involved is total idiot (including designer, his boss, those who approved it, teams that created test program, those who performed testing etc). motors can and do fail but the way i see it, this article can't be serious...

[JesperMP]

Of course it is not serious. It is a teaser. But probably with a "reasonable" rather than silly solution.

[TConnolly]

When operating the motor in a vacuum the motor windings will develop a corona around them (remember vacuum tube electronics?) that will create a locked rotor conditon, causing the windings to overheat and short out. There is no need to develop a fanciful sci-fi setting for this question. Its a problem faced every day by the operators of vacuum furnaces that have integrated gas quench systems on them. I have built controls for several such furnaces. We use pressure interlocks to prevent the operation of the internal blower motor when the chamber pressure is below 500 torr. I have no idea how this problem is handled in a satellite. One more thing, A three phase motor is even worse. Edited November 3, 2006 by Alaric

[TimWilborne]

Yes, I agree, it's a Corona. Do you like yours with or without a lime

[TConnolly]

Corona has a way of stopping many kinds of work...

[TimWilborne]

Cool, so the problems is solved. We now know why. The only question is who drank the last Corona

[panic mode]

uhmmm, team assigned to run tests?

[TimWilborne]

Put me in coach

[PdL]

I'll bring the limes

[IO_Rack]

Don't fruit the beer! Don't you know that's 'Man Law' now.

[BobLfoot]

Yes , even a tea totaler knows you don't fruit the beer!!!

[TimWilborne]

Normally I would agree but in a Corona, the lime just fits Now these people who drink Tequila with lemon and salt, their the ones I can't understand. Tequila is to be drank straight up, no salt, no lemon, and definitely not chilled

[GerryM]

Finally, and I thought I was the only one who thought that!! Salt & Lemon I never understood, other than being some sort of novelty.

[PdL]

Sounds like you never had a good Belgian white beer with lemon! Can't discuss taste though

[IO_Rack]

I spent a month in Belgium some years ago. We tasted many different types. The wheat (white) brews are my favorite. I've never had them with a lemon though. I'll have to break the 'Man Law' and try that.