NASA Engineering Example
 

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 :facepalm:

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

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

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

Get back to crime, commonwealther.

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

They are never going to live that one down.

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....

Or not..

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

I think that's actually a myth.

--Ferdi

Good ol alien technology. I love my cell phone.

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

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.

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 :)

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?

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.

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.

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.

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 :)

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

Can you fix our turbo bolt problem :p

Hey Hustler, my parents are originally from Europe & came on their own free will so thats commonwealthIER to you :p hehehe

Man i cant believe thats a myth, what stories do we tell our grandkids now :vash::giggle:

This.

I need a really motivating summer job...classes just keep getting harder, but threads like this make me feel it's worth it.

Why build a Flux Capacitor when you can buy one from O'Reilley Auto Parts?

http://www.oreillyauto.com/site/c/de...p?keyword=121g

They have Mr. Fusion, too.

http://www.oreillyauto.com/site/c/de...keyword=121gmf

We definitely hire coops for the summer. It is a win-win. The coop gets fantastic real-world experience at a good wage, and we get relatively cheap help.
More info here:
http://www.swri.org/hr/default.htm

Be forewarned, they tend to be really picky about GPAs here. The usual is 3.5 or above but that is not a hard rule. If you have some directly relevant skill they are looking for, or they are trying to hire more than normal, then that could change.

A friend of mine that worked here, Mech Engineer, has a 4.0 from Rice (BSME) AND a 4.0 from Stanford (MSME). Holy crap... :facepalm:

Eh High GPA is for wankers, I have more real world experience on our FSAE team than he probably does. Anyway I have a 2.4 right now so I guess that job is a no go =(. I cant believe I just used a British insult too haha.

This is me. I work 35hrs a week as an engineering assistant, commute 75miles each way to school, and have a family.

I'm hoping someone will see past that low GPA a year from now.

My school was the same way. If you put in the time to really be a part of the FSAE team, it really cost you in grades. So I chose to focus on grades since low grades would cost me scholarships/HOPE Grant which would mean I would have had to take out loans.

I will say co-oping was one of the best things I did in college. Over 50% of engineering students at my college co-oped. It drug out graduation a bit, but when I graduated, I had over a year of real world experience to refer back to during my interviews. It made a huge difference. I also graduated debt free thanks to the co-op income. Work one quarter, pay for the next.

Well, to be honest, my BS GPA was not that great either. Worked all through college, FSAE, etc. My MS GPA is much better. But I got in here through the back door. Long story short they knew my abilities before they hired me, sort of a test-drive.

GPA is important but it is not the end-all. Later on in your career a lot of employers do not even look at it anymore. The problem is for the recent grad positions they get thousands of resumes for a few positions so they use GPA as the initial filter criteria, right or wrong. BUT, coop experience is also very important especially in Engineering. It helps to show you can solve problems in the real world. Two people with the same GPA, both from good schools, but one has coop experience. The one with coop experience is going to get more attention, no doubt.

I will say that being on my third job since I graduated that my GPA was only really taken into account on the first job. Also, a lower GPA is sometimes overlooked if it's a good school. Don't know if that helps or not.

And one last plug to encourage the ME's out there. My BSME has been a very versatile degree. It has allowed me to work as a:
Automotive Assembly Line Support Engineer (co-op)
Tire Design Engineer
Electrical Controls Engineer
Aerospace Engineer

Other majors that are more specialized can do some of the above jobs, but the ME degree is so broad it allows you to do any of them.

Word. Plus the BSME degree is just the toolbox. You learn what you really need to know on-the-job.

I'm gonna get a BSME so I can go into naval aviation. Word.

Let me guess, you want to be a test pilot in pointy nosed jets! That's the recipe I hear. My BIL got his ME degree from the Naval Academy for that exact reason. Ended up flying H60's and got out 3 years ago.
It's funny, he had NO plans on ever using his ME degree so he was the only guy who graduated with one that year that didn't take the EIT. What's he doing now... Tire Test Engineer for Michelin.

God if only I had thought through to that fact when I was in school :facepalm: