Author Topic: The $150 Space Camera: MIT Students Beat NASA On Beer-Money Budget.  (Read 5772 times)

Offline Patchouli

  • Senior Member
  • *****
  • Posts: 4297
  • Liked: 147
  • Likes Given: 260
If you're going to use a model rocket might as well use the bigger engines then a D such as G-80s the biggest you can buy or build without a license or just get a high power rocketry license and use an H and up motor.

Though if I was trying to aim for the edge of space I'd go with a hybrid motor just because you get more control and you can use the N2O for a simple cold gas RCS.
You probably could even get away with using nitrous solenoids originally intended for use in automotive racing applications.

OK it's no long beer money budget but it's still cheap.
« Last Edit: 09/19/2009 02:07 AM by Patchouli »

Offline Robotbeat

  • Senior Member
  • *****
  • Posts: 27335
  • Minnesota
  • Liked: 7282
  • Likes Given: 4990
I imagine that if you had a pressure-fed liquid fuel rocket, you could use the pressurizing gas for cold gas thrusters. That was my plan. There are many small, high-pressure (4500psi) carbon-fibre nitrogen tanks used for paint-ball that have a built-in regulator (down to about 400psi--maybe you can find one that has less pressure for output?). They are relatively cheap, fairly ubiquitous, and quite lightweight. Besides being used for pressurization, the nitrogen could also be used for cold gas thrusters, maybe even instead of gimballing?

But anyways, this pressure-fed system wouldn't work except at high altitudes. If I ever end up making an amateur liquid-fueled rocket, I would try to test it at high altitude on a balloon like these MIT students.

BTW, I made my first small (1 cubic meter) solar-powered hot air balloon and I'm going to launch it tomorrow morning (Saturday). I spent $6 on masking tape and black garbage bags. I have enough materials left over to make a bigger one (about 27 cubic meters) that can hold a payload of about a pound (half a kg), plenty for a camera. I heard these things can go up to 50,000 feet! Yay for free lifting gas!
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline iamlucky13

  • Full Member
  • ****
  • Posts: 1660
  • Liked: 102
  • Likes Given: 93
Aside from the obvious question of, "In what way did they beat NASA?" there's the more revealing question of "In what way did they beat the four teenagers who did this six months ago with a balloon that sent back real time telemetry?"

Well, I'm not an economist, but I am good with the calculator.

The cost for the 4 teenager's system: $1350
The cost for this system: $150

I think that should be a little more clear what this group has done that none other has ;)

Sure, it costs less, but either project was darn cheap, and even rudimentary scientific instruments sending back data in real-time impresses me a lot more than just hanging an off-the-shelf camera with an intervalometer from the balloon.

And really, the author of the article is just asking for it by comparing them to NASA. Picking the appropriate single point of comparison, you can claim just about anything beats anything else. For example:

A Kia Rio beats a Ferrari Enzo because it can hold more people

A shovel beats a backhoe because it costs less

A butter knife beats the space shuttle because opens letters more easily ;)

Offline AlexInOklahoma

  • Full Member
  • *
  • Posts: 177
  • Liked: 0
  • Likes Given: 0
A curious?:  With it being so easy to loft a camera (payload, per se) to extreme heights, are there regulations/rules to follow to avoid men-in-black-suits making an appearance at your doorstep?  Does the FAA or other agency need to know if you are lifting metal cameras or other 'hard' objects into (possible) air-traffic routes even if the items are not in 'controlled airspace', so to speak?  I'm a bit rusty on my air-traffic regs  :-)  Seems that the guys that lofted a few interconnected balloons recently as a joke on the UFO crowd have a bit of an issue, iirr, but may be issue of 'creating a disturbance' rather than a hazard...

Alex

Offline rdale

  • Assistant to the Chief Meteorologist
  • Senior Member
  • *****
  • Posts: 9893
  • Lansing MI
  • Liked: 238
  • Likes Given: 24
A curious?:  With it being so easy to loft a camera (payload, per se) to extreme heights, are there regulations/rules to follow to avoid men-in-black-suits making an appearance at your doorstep?  Does the FAA or other agency need to know if you are lifting metal cameras or other 'hard' objects into (possible) air-traffic routes even if the items are not in 'controlled airspace', so to speak?

If you click the link and go to their website, you'll see it's too light to be regulated.

Offline madscientist197

  • Regular
  • Full Member
  • ****
  • Posts: 1014
  • Liked: 2
  • Likes Given: 0
$150 as the total cost for the system is bogus. In order to be fair it needs to take into account the value of the time invested by the students -- suddenly it won't seem so cheap. Comparing the cost of raw materials for this system to a NASA meeting budget isn't a sensible comparison.
« Last Edit: 09/19/2009 12:17 PM by madscientist197 »
John

Offline AlexInOklahoma

  • Full Member
  • *
  • Posts: 177
  • Liked: 0
  • Likes Given: 0
rdale: thanks :-)  I almost always avoid any link that uses 'leet' of any spelling.  The breakaway strength of connecting rope is what interested me most, and nice that there was a direct FAA link - this'll be a great homeschool project for my daughter and I!  I have most of the things needed already and its just a short drive to middle-of-nowhere, so this is very doable.  Now to just work it into a 'lesson-plan' and convince the wife, LOL.

Alex

Offline rdale

  • Assistant to the Chief Meteorologist
  • Senior Member
  • *****
  • Posts: 9893
  • Lansing MI
  • Liked: 238
  • Likes Given: 24
$150 as the total cost for the system is bogus.

Uhhh, no it's not. If I want to duplicate it, it'll cost me $150. If I want to duplicate the Spanish high schooler's, it'll cost me over a grand. I'm not sure I understand what you mean?

Offline madscientist197

  • Regular
  • Full Member
  • ****
  • Posts: 1014
  • Liked: 2
  • Likes Given: 0
Because people are making apples to oranges comparisons. Earlier in the thread Norm (I'm not getting at anyone here ;) ) mentioned that $150 would be more than the NASA meeting budget required. Comparing this to the student budget, which has no allowance for the value of their time is unfair. For example, buying excessively cheap equipment might result in assembly taking hours longer, which might negate any savings made. It might have been more optimal to spend an hour working at a video store to earn the cash to buy more expensive equipment that then takes hours less time to build. If we don't take into account the time donated, then we are not making a fair comparison between the true costs of developing each system.

If I want to duplicate it, it'll cost me $150.
...And a lot of time (which you didn't mention).

It's not fair to take into account the value of NASA employees time and not that of your own (not that I'm saying that you made this particular comparison ;) ). Just because someone chooses to donate their time, doesn't mean that it doesn't have any financial value!


It's just that if someone wants to say that the students did a better job than NASA was capable of doing, I would prefer it to be a fair comparison that takes all factors into account.
« Last Edit: 09/20/2009 09:04 AM by madscientist197 »
John

Offline rdale

  • Assistant to the Chief Meteorologist
  • Senior Member
  • *****
  • Posts: 9893
  • Lansing MI
  • Liked: 238
  • Likes Given: 24
I see - well I wasn't comparing to NASA, I was comparing to my ability to duplicate ;) If it takes me a few hours and $150, that's something I'd try with my kids. If it takes me a few hours and $1300, that's something I won't try.

They made the cut for me...

Offline Downix

  • Senior Member
  • *****
  • Posts: 7087
  • Liked: 16
  • Likes Given: 1
The Rocket Modeller II java applet on nasa's site is a good way to answer some of these questions.

A simple pressure-fed liquid fuel rocket engine is a good fit for this, since you can get away with a much lower combustion chamber pressure when you're at 100,000ft. That's how I'd do it, anyways.
You are EVIL for telling me about this applet....

Been working on designs now for 5 hours.  8)
chuck - Toilet paper has no real value? Try living with 5 other adults for 6 months in a can with no toilet paper. Man oh man. Toilet paper would be worth it's weight in gold!

Offline Bubbinski

Yeah, that applet got me hooked.  I have been trying to make a model rocket that would launch into lunar orbit.  The best I've done so far is a 2 stage design with C engines (and VERY little else, just a paper tube and tiny paper fins, which I tried to remove but could not) - and I've been able to make it to a little over 4700 FPS.  But I think I need over 6000 FPS to make it into lunar orbit, can someone confirm?
I'll even excitedly look forward to "flags and footprints" and suborbital missions. Just fly...somewhere.

Offline Downix

  • Senior Member
  • *****
  • Posts: 7087
  • Liked: 16
  • Likes Given: 1
Yeah, that applet got me hooked.  I have been trying to make a model rocket that would launch into lunar orbit.  The best I've done so far is a 2 stage design with C engines (and VERY little else, just a paper tube and tiny paper fins, which I tried to remove but could not) - and I've been able to make it to a little over 4700 FPS.  But I think I need over 6000 FPS to make it into lunar orbit, can someone confirm?
I can't get above 2400fps.
chuck - Toilet paper has no real value? Try living with 5 other adults for 6 months in a can with no toilet paper. Man oh man. Toilet paper would be worth it's weight in gold!

Offline Bubbinski

"I can't get above 2400fps." - is this with the same design?  I'm using 2 ply paper for my tubes (shrunken down to barest minimum size), no fins on the first stage, only 1 ply paper fins on the 2nd stage (which I can't seem to get rid of, so I shrink them down to the minimum possible size), no nosecone, no recovery system, no ballast, 2 C engines.  Essentially, the rocket is a pair of engines and nothing more.

Edit: Launching from the moon, with my latest tweak, I can make it up to 4800 FPS.  I can get up to 408 miles high and the thing can fly past 800 miles if I'm launching for distance.  On Mars, I can only make it up to past 35000 feet (60000 feet was with another design) and on earth past 2000 feet in altitude (3000 feet with other designs optimized for atmospheric flight, with nosecones).  The moon would be paradise for amateur rocket builders if they can ever make it up there.....
« Last Edit: 09/21/2009 04:15 AM by Bubbinski »
I'll even excitedly look forward to "flags and footprints" and suborbital missions. Just fly...somewhere.

Tags: