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Vancouver Off-Topic / Current EventsThe off-topic forum for Vancouver, funnies, non-auto centered discussions, WORK SAFE. While the rules are more relaxed here, there are still rules. Please refer to sticky thread in this forum.
Don't get me wrong, a human power helicopter is pretty wicked to see. But propulsion jet packs please.
EDIT: Read more in to it, the Canadian guys were smart. I didn't know this prize was dated back in the 1980's, and only now these guys have won it.
$ 250,000.
If anybody cares, the bike frame used is by Canadian-based company Cervelo (now owned by a Dutch company.) This was the same bike frame that brought Victoria's Ryder Hesjedal to win the 2012 Giro d'Italia. MSRP on the frame alone is I believe $9,800.
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Originally Posted by Badhobz
You show me a 1998 240sx in prestine condition and ill fucking suck your dick. no homo!
Nope. They didn't get high enough. The reason the Sikorsky Prize requires a minimum height is because of the ground effect. Ground effect provides additional lift to a wing or rotor that's close to a fixed surface (like the ground ).
The other rules state you must fly for 60 seconds and you can't move outside of a fixed box (10m per side). If you watch other Maryland videos you'll see they have trouble keeping their machine still - it wants to travel. Although the Maryland team did break a record in one flight of 65 seconds, they only reached an altitude of 8ft.
A couple observations... Looking at that cyclist struggle, I'm curious why they didn't adjust the gearing on the pedal setup to allow him to "cycle" more easily while keeping the same rotational speed of the rotors. And speaking of the rotors, I'm super surprised at how slow those things were rotating. I wouldn't have thought a rotational speed that slow, despite how large the surface area of those rotors are, would have been able to keep the whole structure afloat. I'm quite impressed. As someone getting into mechanical engineering come fall time, there's certainly a lot of preconceptions I need to rid myself of.
But just like how an automotive transmission or bike gears work, you can maintain the same speed while adjusting to a different gear. I haven't taken a close look at how the design was built, so I'm not quite sure how the rotors are running in conjunction with the pedals. I'm sure there's a very valid reason why even adding in a second "economy" gear wasn't done; I'm just curious why it wasn't.
A couple observations... Looking at that cyclist struggle, I'm curious why they didn't adjust the gearing on the pedal setup to allow him to "cycle" more easily while keeping the same rotational speed of the rotors. And speaking of the rotors, I'm super surprised at how slow those things were rotating. I wouldn't have thought a rotational speed that slow, despite how large the surface area of those rotors are, would have been able to keep the whole structure afloat. I'm quite impressed. As someone getting into mechanical engineering come fall time, there's certainly a lot of preconceptions I need to rid myself of.
Torque, if you give the cyclist a smaller gear it would indeed be easier to cycle... but only once you get the rotors up to speed. Those rotors are huge and there's no way he would be able to transfer the torque from his legs to get the rotors to move at all if they used that gearing.
It would be like trying to start your car in 6th gear, sure, by the time you hit 100km/h your engine not under a lot of stress, but your engine wouldn't be able to get the car moving at all.
If the cyclist was a car he would be in "3rd" gear, you can still get the car moving (although it will struggle a bit, like the cyclist) but it's still capable of geting up to highway speed albeit at high revs (again, the cyclist struggling to maintain a high rate of revolutions)
I do a lot of robotics and we can never run a "robot arm" direct drive off a motor at 3000 RPM for example, it will not move at all. We need to do a gear reduction that slows down the motor movement to about 100RPM, the arm will move 30X slower but there's enough torque to actually get the arm to start moving (and also, a robot arm moving at 3000RPM is actually a bit scary and out of control)