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Human Powered Paper Airplane
gilgsn writes: "The Raven is a honeycomb paper, foam and graphite-fibre tape, human powered airplane designed to beat the current record held by MIT's Daedalus . The plane is also powered by a 16MHz Motorola 68332. The technical specifications of the onboard computer are pretty interesting. Unfortunately, as reported on Ananova, the Raven recently crashed a mere 100 feet after taking off, causing some damage to its fragile structure. Maybe they could upgrade to a Pentium and convinced Lance Armstrong to give it a try..."
As one of the control engineers who worked on this project, I can tell you there is no need to upgrade to a Pentium. The customized Tattletale system we were using had more than enough power.
The problems that I saw with this project had less to do with the control system and more to do with the airframe. The airframe was damaged a number of times and was extremely fragile. Damage probably occured during every flight test.
For those who are interested, I worked with the RAVEN team 2 years ago. I was resposible for getting an ultrasonic altitude sensor (primary) and a barometric altitude sensor (backup) to co-operate. The idea was that if the ultrasonic device failed the barometric would take over. The reason the barometric device wasn't the primary sensor was because of drift due to weather changes. Accuracy was important because the pilot was not a pilot, but rather an engine. The control system was in charge of maintaining altitude and heading.
It seems relevant that this link should be noted. Seems like the project's run out of funding?
Paine Field is about 3 miles away from my house, if that. It's right across the 'street' from the Boeing 747/767 assembly plant -- you know, the "world's largest building"? (Largest, I suppose, in that it covers more land than any other building -- it's not particularly tall.)
I saw a news bit recently (last night?) about the crash... looked like one of those 'impending doom' situations, where you know things are going badly, and there's nothing you can do to stop it. Unwieldy looking landing gear, but necessary for the size of the prop the fellow is turning. I'm amazed there was as little damage -- it looked worse.
Here are some links from local news:
- Human-powered plane crashes on first flight
- Test flight for the human-powered Raven
- (includes post-crash picture)
- 'Raven' debuts at Museum of Flight (includes pre-crash picture)
Doesn't look like the pilot has much for visibility. It's one of the most recumbant positions I've seen for human-powered flight. When they were pulling him out, it looked like he's almost strapped to the underside of the spar!Incidentally, the Boeing hangar (the 747 assembly building) is where some of the human-powered helicopter (!!!) tests have been conducted. It's the only indoor place large enough, and the tests have to be indoors because they need absolutely calm air.
"...America's great minds of today, teaching America's great minds of tomorrow. Poor bastards." -- A Beautiful Min
Uh -- what you threw was a glider , not an airplane .
The best diplomat I know is a fully activated phaser bank.
-- Scotty.
A human could produce that much, and probably much more; if and only if they (most anyways) weren't fat sacks of lard. Maybe a CS person couldnt. Average Joe shure could. Whilst cycling, an average person could train to produce 300 watts over an hour easily. If you have some dedication, and are fit otherwise, you could probably do 500-700 watts. I don't know alot about Lance Armstrong, but I bet he (and no doubt many ohter cyclists) could do that 500-700 watts for a very (relatively, anyway) long time.
Don't get me wrong, I understand that it is best to keep the power requirement of the electronics down to minimal, for many reasons. Maybe they could have used a transmeta or something, but who cares. If a 16Mhz dragon ball was all they needed, then that's what they should use. Hell, I'd let them use my Handspring Visor if it made the job any easier (it can run for a freakin long time on a single charge) --though I suspect that it is well in their budget, given all the composite work.
One of the advantages of older processors is their lack of cache. This is important if deterministic timing is a requirement. The main engine controllers on the Space Shuttle use redundant pairs of 8 MHz Motorola 68000 processors.
Mea navis aericumbens anguillis abundat
After surfing the site a little more, I ran across this news item, which was the most recent one on the site and seems to me to be of some significance to this story:
Wednesday, December 12, 2001
RAVEN Project closing - Paul
Raven team members,
It is with great regret that I must announce that the RAVEN Project is
shutting down. The numbers have caught up to the project. There just
aren't anymore resources available to for us to continue. At the end of the
year our lease expires and there is just enough money to cover that debt.
My financial position does not allow me the option of continuing any
further.