HALE Mission - Lil' Joe

Primarily a "how to" video for the folks that will be preparing & launching the payload (sorry it's not more polished), it also give you a taste of how the payload is put together and functions. For more information, visit the HALE website at:

http://www.unr.edu/nevadasat/HALE/

For more still photos, visit my Brickshelf folder at:

http://www.brickshelf.com/cgi-bin/gallery.cgi?f=324334

Summary: The idea is for the "Lil' Joe" payload to be carried up to roughly 80,000', and then cut free from the main payload string to perform an independent free-fall, deploying its own parachute after a brief (20 second to more than a minute) free-fall period. At altitude the pressure is approaching 1% of sea level pressure, and the temperatures are very very cold (-50° C or lower). All control functions are programmed using NXT-G running on a LEGO NXT, and to find the payload after the drop a SPOT unit is along for the ride.

And yes, of *course* there's a minifig riding along :)

Category:

Science & Technology

Tags:

• HALE
• NXT
• LEGO
• high-altitude
• robot
• free-fall
• Kittinger
• aviation
• space
• computer
• diy
• gadget

[softballxchick3]

(I got this idea from your packbot) Maybe, on the object with the tooth, you can put a minifig in a seat with control panels around him as if he is controling it. Like the idea?

[brdavis5]

Well, there's two small problems with this suggestion. First, the mission already happened... in fact, the Lil' Joe payload is right now over in Denmark at a 10th anniversary Mindstorms event at LEGO HQ. 2nd, if you look in my HALE Brickshelf gallery, you'll see there *was* a minifig passenger - I now have several minifigs that have been exposed to near-vacuum at 80k feet :)

[musician774]

did u ocme to the IBM camp and bring the Ogre tank???

[brdavis5]

No, I didn't but I heard somebody did - any idea who? Pictures or video of the event?

[Coastergeekperson04]

How do you recover it? What if you attached it to an RC balloon and a built-in altimeter will release it from the balloon and the balloon with simply go off uncontrollably while Lil' Joe (or another one to handle lower altitudes) will come down. Then you can't get higher altitudes but you don't have to go up 80,000 feet.

[brdavis5]

Ah, but the fun was in going up to 80k+ feet :). Read the HALE webpage - essentially what we did was drop it from an "RC" balloon (the drop was commanded from the ground) and Lil' Joe came down... fast!

[brdavis5]

Either could happen - but during the actual mission, the LEGO pieces did not break (even though Lil' Joe hit the ground at something like 25-30 mph, and Gypsy, my other payload, was supported entirely by the LEGO construction). Some pins started to pull loose, but because of the way the structure was cross-braced, it seems no connections failed in flight - when you use LEGO right, it really holds up (even to -60° C and high impact speeds).

[Coastergeekperson04]

I haven't watched the full video yet, but if it breaks, do the Legos separate from each other or do the Legos themselves break?

[brdavis5]

Thanks... and while it didn't all go exactly to plan, I'll call any similar mission where I retrieve a working NXT as "successful"... if not according to plan. The free-fall time depends on what you want to call it. The parachute was deployed at 61 seconds according to the on-board log, but there was no deceleration from it - in other words, even with the parachute out it was "in free fall", so it then becomes a question of what you want to label it as.

[peterwallhead]

Nice work on the *nearly* successfull mission, I have been reading reports about this all week. Do you have an officail time for the free-fall yet? I've been reading between 61 to 90 seconds.