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Celebrating Spirit, The Mars Rover 4

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tomwalz

tomwalz

Materials
May 29, 2002
947
She doesn't answer any more but she ran years past her design life. Nice job on the engineering and design. A salute to all the men and women involved.

Thomas J. Walz
Carbide Processors, Inc.

Good engineering starts with a Grainger Catalog.
 
Or arguably, she was well over designed/engineered (if you want to argue the term look here thread1010-292852) for the original requirement and presumably there fore more expensive than necessary.

As a tax payer I want a refund.

;-)

Posting guidelines faq731-376 (probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​
 
Note that Spirit's sister rover, Opportunity, is still going strong and sending pictures back to Earth on a daily basis:


John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

To an Engineer, the glass is twice as big as it needs to be.
 
Kenat, consider Opportunity's successful longevity as payback rather than refund.

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read faq731-376 to make the best use of these Forums?
 
Oops, insert [tongue] above.

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read faq731-376 to make the best use of these Forums?
 
Dear Kenat:

From your posts I always assumed that you were the type of person who enjoyed designing / building something that outperformed while coming in at or under all budgets.

I think that is what happened here.

Tom



Thomas J. Walz
Carbide Processors, Inc.

Good engineering starts with a Grainger Catalog.
 
Hey Tom, I put a ";-)".

You should know I'll often play devils advocate just to make sure people have really thought through their own position, not necessarily because I disagree with their position.

It really is an achievement, plus as long as they're gathering useful data then even if arguably more expensive than needed for their original requirement, they may well be a worthwhile investment.

Posting guidelines faq731-376 (probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​
 
Dear Kenat:

I am aware of your propensity for playing Devil's Advocate.

I very much admire your ability to broaden issues in an entirely relevant manner.

I am also an admirer of yours and you do strike me as someone who takes great pride in the quality he delivers.

I agree with you about the added expense. But it is still a really cool thing.

Tom

Thomas J. Walz
Carbide Processors, Inc.

Good engineering starts with a Grainger Catalog.
 
"She doesn't answer any more but she ran years past her design life."

Sounds like my wife - but she is still alive!!!
 
KENAT said:
...even if arguably more expensive than needed for their original requirement...
Click to expand...

Of course you do have to take into consideration that we're talking about conditions on the surface of MARS so I would suspect that the specifications that they were working from had a bit more latitude than what most engineers are presented with when they are starting a new design for some Earth-bound application. Besides, since making on-site service calls were going to be a bit impractical, I assume that this was justification for spending a bit more on redundant systems ;-)

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

To an Engineer, the glass is twice as big as it needs to be.
 
Tom, stop it, I'm blushing, but thanks.

Posting guidelines faq731-376 (probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​
 
To some degree, there is no overdesign. Designing for a 3-month minimum life is like trying to design a system with a minimum of 64k DRAM.

At this point in history, designing for that minimum would actually cost you more money, because parts that bad or small don't even exist anymore, except in surplus stores, or in some hideous reclamation yard in China or India. So, you build to the smallest DRAM you can find, which is around 256 MB, which is 4000 times your requirement.

Likewise, most electronics, except the stuff that we buy, already far exceed 3-month (5-[σ]) reliability. Even in the 1980s, there were semiconductor companies with processes so reliable, they didn't even include test devices on their wafers.

So, in actually, to design for a 3-month life, only, could actually have been more expensive design alternative.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
Geez, did everybody have a sense of humor bypass earlier today or something.;-)

Posting guidelines faq731-376 (probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​
 
Kenat,

Were you even a US resident, much less a citizen, when Spirit was designed and built?

I don't think you're entitled to one penny of that refund.
 
Citizen no, resident probably not when designed but yes when launched. Anyway I'm fighting for my wife's share.

Posting guidelines faq731-376 (probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​
 
By my calculations, your wife owes 23 cents, since my estimation is that we saved about 10% of the $312.5M cost by not using parts that only just low-side compliant. Divided by 134M individual taxpayers, and you owe 23 cents.

So, PAY UP!!

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
Tell you what IRstuff, I'll buy a postage stamp and not use it, that should more than cover things.

Posting guidelines faq731-376 (probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​
 
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