ZX-Tex

iTrader: (15)

I am doing some research at work today and was reading up on the CRISM instrument that is part of the Mars Reconnaissance Orbiter (MRO). This is a mission that is orbiting Mars right now and has been sending back phenomenal data about the planet.

Check out the engineering that went into the CRISM instrument design.

From the article:
And strap it to the top of a rocket (rough ride) to send it on its way, and it absolutely has to work when it gets there, and...

http://crism.jhuapl.edu/instrument/innoDesign.php

And people wonder why this stuff is so expensive

sprx3

bahhhh Dr Brown made a flux capacitor in his own home......

on another note, Nasa spent millions designing a pen that would work in space........

USSR used a pencil ........ hehehehe

hustler

iTrader: (6)

Get back to crime, commonwealther.

chicksdigmiatas

iTrader: (11)

Pretty awesome stuff. Lots of our technological advancements come from nasa.

ZX-Tex

iTrader: (15)

They are never going to live that one down.

neogenesis2004

iTrader: (12)

Yes, but how much money have they made from licensing technology that allows pens to write upside down? Probably more than it cost to design it....

Newbsauce

iTrader: (2)

Or not..

http://www.scientificamerican.com/ar...tion-nasa-spen

ftjandra

iTrader: (6)

I think that's actually a myth.

--Ferdi

turotufas

iTrader: (7)

Good ol alien technology. I love my cell phone.

TurboTim

iTrader: (9)

And lost his entire family's considerable wealth in the process.

Savington

iTrader: (31)

http://www.snopes.com/business/genius/spacepen.asp

Sparetire

A 1/100 of a degree C alters the instruments readings. One part of the diagram they show has a component that has to be at -260, which appears to be about 2 inches from another component that had to be at -76. And they are both hyper sensitive detectors of some sort which just got blasted up the gravity well at about 4G average with a ton of vibration.

But dont worry. I'm not an engineer, but I did stay at a Holiday Inn Express last night.

Wow.

ZX-Tex

iTrader: (15)

Yep. The highest stresses on an instrument from the launch typically comes from the random vibration profile, that is the engine roar that is transmitted from conduction through the structure and also acoustically to the payloads. This random vibration is complex by its nature and usually handled with an envelope profile. But there is something called the Miles Equation that lets you convert this to a comparable steady-state or 'quasi-static acceleration' load. This allows for easier modeling and design.

For example of how big these loads are, I have been running some numbers lately for an instrument design I have been working on. The quasi-static acceleration load I am using (based on the random vibration profile for this mission) is 188g, or 188 times Earth gravity. That is pretty typical for a 3-sigma stress level determination. So that instrument I linked to probably went through the same thing. They would have used something large like an Atlas rocket to launch an interplanetary mission, which is what ours would be using.

You should see the Shaker Table tests that simulate the vibration loading. It is pretty violent for a spacecraft payload. It will break stuff that was not designed and/or built properly. Fortunately the instrument I built and just tested did not break

Sparetire

Gawd how that must feel to see all that work made matirial and then subjected to that. It would be like watching your kid in his first boxing match.

What do you do anyway?

ZX-Tex

iTrader: (15)

Awesome, thanks. I never bothered to check up on that story, don't know why. What they say about the hazards of graphite bits floating around the cabin is definitely true. We have the same problem with instruments and circuit boards. If something conductive comes loose, it could float into something else and cause a random short. Some of these instruments use high voltages to operate, like 5000V, so it does not take much to cause a big problem. No repairs in outer space for anything higher than the shuttle orbit, and even then they only bother with the really expensive/nice stuff, like Hubble.

ZX-Tex

iTrader: (15)

I am a Mechanical Engineer working for a large R&D firm in San Antonio. The Division I work for develops scientific instruments and electronics (computers) for NASA, the European Space Agency (ESA), and military missions. I work with the scientists here to turn their crazy (but brilliant) ideas into flight hardware. Design, build, test. Very challenging, but fun stuff.

Sparetire

Cool. Thats the kind of work thats fun enough to get you through the damned spreadsheets and all AFAIK.

Doesnt air conduct across about 1CM with a 20K volt difference?

Would a high 02 environment be less? Boom.

ZX-Tex

iTrader: (15)

Word

I usually deal with hard vacuum, which is basically a near perfect vacuum, almost nothing in it. For that we use about 1000V/mm as our standoff distance rule of thumb.

Fortunately we do not deal much if ever with manned space flight environments and therefore I do not have to worry about that

cardriverx

iTrader: (12)

cool soooo you guys take in any mech E co-ops?

Faeflora

iTrader: (2)

Can you fix our turbo bolt problem