Slashdot is powered by your submissions, so send in your scoop

 


Forgot your password?
Close
typodupeerror
×
It's funny. Laugh. Science

Whirling Twirling Propeller Trike 136

Posted by CmdrTaco from the mit-students-with-to-much-time dept.
hankmt writes "A student at MIT has built a tricycle that applies force to a giant rear fan, instead of directly to the wheels. The effect...well, it's best to look for yourself, but it would be pretty useful on the post-apocalyptic roads of the Australian Outback. The blades of the trike even have built in LED lights which display colored patterns...and also warn pedestrians of their impending deaths."
This discussion has been archived. No new comments can be posted.

Whirling Twirling Propeller Trike More

Whirling Twirling Propeller Trike

Comments Filter:
  • There would be a lot more room to ride on Multi-Use Paths...

  • Crazy (Score:4, Funny)

    by grub ( 11606 ) <slashdot@grub.net> on Wednesday July 04, 2007 @12:18PM (#19744357) Homepage Journal

    Those crazy MIT guys are lucky that Massachusetts just made health insurance mandatory!

    • Re: (Score:1, Insightful)

      by Anonymous Coward
      What's really crazy, is that when someone at MIT takes a brown shit - it's front page news as a golden egg. :/

  • First prize for impracticality (Score:3, Funny)

    by trolltalk.com ( 1108067 ) on Wednesday July 04, 2007 @12:19PM (#19744371) Homepage Journal

    From the looks of it after watching the vide, its terrible at transforming pedal energy into forward motion, and I'd really hate to see what would happen in any sort of wind. At least a "real bike" you can get off and walk. Add bird strikes to the blades, the excess width, etc., and you've got a real problem.

    Unless,of course, you're Wiley Coyote, and ride it off a cliff - you could autogyro down, I guess.

    • Re: (Score:2)

      by Speare ( 84249 )
      I don't think the guy is trying to transform the energy debate, he just thought it would be fun. It reminded me of the bicycle in Miyazaki's "Castle in the Sky" (aka Laputa). And by the way, that's "Wile E. Coyote".
    • This thing couldn't even get started on an uphill, or with more than a light breeze for a headwind. Forget climbing out of a pothole.

      It's a very clever toy, nothing more.

    • Re:First prize for impracticality (Score:5, Funny)

      by timeOday ( 582209 ) on Wednesday July 04, 2007 @12:49PM (#19744647)
      Oh well, millions of people per year spend good money on devices that do nothing *but* waste energy, such as elliptical machines, treadmills, and exercycles. And you can't even hack people to pieces with those.
    • Go slow, use legs.
    • autogyro down?

      Did you ever actually watch the cartoon?? if there is ONE thing Wile E. Coyote excelled at, it was falling off the cliff!

      • Re:First prize for impracticality (Score:5, Funny)

        by trolltalk.com ( 1108067 ) on Wednesday July 04, 2007 @01:47PM (#19745271) Homepage Journal
        But in this case, he'd autogyro down, with that big sh*t-eating grin on his face, holding up a sign saying "PHEW!" and just as he gets to ground level - BAM! a truck driven by the RoadRunner runs into him and creams him.
        • Unless the blades are variable pitch, he ain't even going to autogyro down. The way it works is to unclutch the rotor from the engine, the airflow spins the rotor up. At the correct time, i.e. right before you pancake into the ground, you pull up on the collective. That increases the pitch of the blades which creates more lift. The down side of this is that it slows down the rotor.

          • Re:First prize for impracticality (Score:4, Informative)

            by tylernt ( 581794 ) on Wednesday July 04, 2007 @06:19PM (#19747951)
            Gyroplanes (or gyrocopters, if you wish) auto-rotate all the time and can still do a zero-roll landing without a collective. The rotor speed is controlled by the angle of attack to the relative wind so you come in at speed and then flare at the last moment... not that that would really help a guy going down in this trike though, as he would have no control surfaces.

    • Re: (Score:2, Interesting)

      by hszp ( 1023419 )
      Disclaimer: I would not want to pedal that sh!t uphill under any circumstances.

      But it's simply great. How many of you would have thought such speed was possible in such an unefficient way? Sure: he could be three times as fast with an everyday ( "run-off-the-mill"? ) bike, but that's only better by a factor of 3.

      Add a big helium-filled balloon to the thing and next thing you see he's flying (don't try this at home kids, you're not coming down the way you think you would).
      Or build something similar for a gli

      • Re: (Score:2)

        by harrkev ( 623093 )
        Maybe he needs to mount this to a lawn chair tied to a bunch of weather balloons. Don't forget the BB gun.
    • In any case, it doesn't use gas, elecricity, biodiesel, or any other fuel. IMHO, this is pretty cool, if he gets his safety aspects together, and works on gear drive, it could be a neat little invention that he might be able to sell. It seems like something that Leonardo would have drawn plans for. Anybody else think so?

      • Re: (Score:2)

        by E++99 ( 880734 )

        In any case, it doesn't use gas, elecricity, biodiesel, or any other fuel. IMHO, this is pretty cool, if he gets his safety aspects together, and works on gear drive, it could be a neat little invention that he might be able to sell. It seems like something that Leonardo would have drawn plans for. Anybody else think so?

        If you mean DiCaprio, absolutely. Da Vinci, OTOH, would probably have given his right arm to have invented the internal combustion engine. In any case, he was smart enough to realize that

      • The fuel it uses is the cheeseburger you had for lunch.
  • This isn't science, this is technology. Very cool machine though; I especially like the complete lack of any safety measures concerning the big spinning blades! Can I hire that thing to get rid of my evil enemy Mr. Naughty?
  • It should be pretty obvious that the effeciency of a propeller driven bike is way less than a bike driven by it's wheel, particularly one with multiple gear ratios. Just watch the video, the guy is pedalling pretty damn hard for not much speed (maybe he talks about that later in the video, I got bored half way through...)

    I guess this proves that just because you can do something doesn't mean that you should.
    • Maybe he wants to use those blades to display '3-D' images with his LEDs?

      I am not sure if this is what he does, maybe not, since it isn't that easy to figure out how to wire up enough LEDs in a line and update those based on their angular position. A mechanical engineering undergrad that can use microcontrollers?
      • Already been done. Go to Hokey Spokes [hokeyspokes.com] and take a look at the demo video.
        • Great link, thanks. I did think he might try something along these lines since the rotation plane is actually more suitable for displaying it to traffic (perpendicular to the road and would work when the bike is stationary or moving slowly). Too bad TFA is not saying what exactly he does with the LEDs.

  • Pfft.... (Score:4, Funny)

    by Digitus1337 ( 671442 ) <lk_digitus@h[ ]ail.com ['otm' in gap]> on Wednesday July 04, 2007 @12:29PM (#19744477) Homepage
    That thing blows.

  • I can't believe Slashdot. (Score:5, Funny)

    by pclminion ( 145572 ) on Wednesday July 04, 2007 @12:35PM (#19744541)

    This guy builds a trike with great glowing, whirling blades of death on the back and actually manages to ride it around for a while without getting shipped to Gitmo, and people just complain how it's not practical?

    You people fail utterly at nerd-dom.

  • Looks like something for Burning Man (Score:4, Interesting)

    by Animats ( 122034 ) on Wednesday July 04, 2007 @12:37PM (#19744563) Homepage

    The Burning Man crowd likes stuff like that. It's too late for this year's Department of Mutant Vehicles [burningman.com] registration, though.

    By playa standards, this is unambitious. Check out the Neverwas Haul [tribe.net], a steam-powered 3-story Victorian house on wheels that moves under its own power.

    • Re: Looks like something for Burning Man (Score:1, Interesting)

      by Anonymous Coward
      The Burning Man "Department of Mutant Vehicles" doesn't need to get involved because it's not a motor vehicle; so I'll be keeping my eyes out for the big, glowing, spinning fan blades of certain death/concussion/brokenarms.

      Also: the Neverwas Haul, while very cool to look at, was not self-powered. It was towed by a steam tractor (which is still pretty cool). Perhaps they've modified it since last year and, if so, I hope to see it out on the playa again.
  • Look at where the chain is... What if he hit a pebble or something and flew forward?
  • You noticed he's walking it?

     
  • It seems like if he build a simple lightweight fan cage, he'd probably solve most of the problems with unhappy police or others. It also could save him money and trouble if he ever tips over, cuts a corner too close, hits a bird, etc. I'm sure fiberglass over foam wouldn't hold up too well to a sudden interruption.

    That said, it's still pretty cool. I wonder how it compares to normal bicycle drive for efficiency.
    • A regular bike is much, much, much more efficient. I don't know exactly how much without a wattage output vs. distance measurement, but there's no way this could be anywhere as efficient as a normal bike.

      However, it is really awesome. :)
      • Are these fan-driven things any better once they get going at a good speed? Compared to a traditional bike, you lose the drag of the drive train, if there is any. But the big advantage would be if you could get the wheels off the ground. But I don't see how disconnecting the chain from the wheels allows enough design freedom to improve the aerodynamics much.

        • Compared to a traditional bike, you lose the drag of the drive train


          In which case, what does the rider of the propeller trike use to translate pedel rotations into fan rotations?

          I guess it would be a drivetrain, which will have similar bend/straighten frictional losses in the chain compared to a regular bike.

        • Compared to a traditional bike, you lose the drag of the drive train, if there is any.
          There isn't. [wikipedia.org] Not appreciably, anyway. And this thing's frontal area is monstrous. This thing's big advantage is its whirly choppy blades of doom.

    • Re: (Score:2)

      by Hadlock ( 143607 )
      Weight! If he tips over the blades should be able to support their portion of the bikes' weight - the operator simply falls out. Fiberglass is rediculously easy to repair. An enclosure for the fan would probably increase the weight of the bike by 20% or more if it was at all load bearing.

    • Re: (Score:1)

      by orlanz ( 882574 )
      The fiberglass over foam actually holds up pretty well. It may crack, but won't break off into pieces that go flying all over the place (if it was going fast enough to do that, then it would be making a ruckus like an airplane propeller).

      And it is probably far more inefficient than a normal bicycle. Constantly pulling air from in front of you faster than it is flying by your whole vehicle in order to create thrust has to be less efficient.

      Also, bicycling is the most efficient mode of transport there is.
    • Hmm, if he fully encloses the fan and adds a vacuum pump, then the fan will spin much easier and his forward speed will be pretty much the same...

      • Re: (Score:2)

        by Reziac ( 43301 ) *
        Or something like those new vertical fans they're now selling for household use. In fact he might be able to mount 3 or 4 of those side by side without going beyond the vehicle's wheelbase width ... the engineering might get more complex but the added power and maneuverability might be worth it.

        Also would probably have less negative effect from headwinds.

        Regardless, it's cool and I want one. :)

  • Or at least drew it first in Kiki's Delivery Service [imageshack.us].
  • Anyone see any brakes on the thing? Or does the driver just start blowing air out of their mouth forward?

    -m

    • Re: (Score:1)

      by mcarp ( 409487 )
      well if he REALLY needs breaks he can simply turn the fan in reverse you imbeciles. altho at the speeds he's traveling i doubt breaks are much of a concern. its just cool ok?

      if anybody wonders why he built it then look at your stupid case mods.

      • Re: (Score:1)

        by diskis ( 221264 )
        You ever heard about inertia? Stopping and reversing the blades requires a lot of energy. I learned the concept of inertia when I got my first gearless tricycle at the age of 3, and nearly broke my leg when suddenly trying to brake and the pedals kept on turning.
      • Here's a simple test for you. Try driving your car at about 20 km's an hour... and instantly jamming it into reverse. Those gears that are now lying on the road behind you? That'd be what's left of your knees if you tried the same thing on the bike.

        I'm sure it'd be easy to have a hand-brake to lock the rear tires, and just slide to a stop that way... or perhaps a disk-brake system for the spinning fan itself... but simply attempting to reverse the blades... being helped along with movement mind you by th

    • Re: (Score:2)

      by Alioth ( 221270 )
      That's the next step of the project - being able to put the prop into beta. Either that or thrust reverser buckets!

  • "durr, they jump out of the way even..." (Score:5, Insightful)

    by SuperBanana ( 662181 ) on Wednesday July 04, 2007 @01:46PM (#19745251)

    (from the video) "...and they jump out of the way even if they're 20 feet away."

    That's pretty smart on their part. Pay close, careful attention to how he restrains these spinning blades: A FUCKING PIPE CLAMP.

    Maybe if he's so smart with matlab, he can work out the pulling force at a few hundred RPMs on those blades, frighten himself, and put a bolt through the blade and hub shaft.

    Also, the design of the frame is pretty sketchy, with no bracing; he's relying purely on the static-load-bearing capacity of the tubing and his welds. If he collides with anything, the frame is going to come apart, and he stands a good chance of getting a chromalloy chest transplant.

    • Re: (Score:1)

      by brycef ( 866665 )
      They are not even pipe clamps. They are hose clamps. YIKES!!!
    • Given his complete disregard for safety, I could care less if he impales himself. I'd be more concerned of the blades breaking off and slicing through the air towards some poor bastards out for a walk in the area. Maybe if he finds himself with only one lung or a colostomy bag, he might thing twice before making some dumbass murdercycle again :P
  • Hwever, adapting the LEDs to beanie propellors could be cool.

    • Re: (Score:2)

      by Loligo ( 12021 )

      On the upside, you wouldn't have to pedal nearly as fast for a little tiny beanie propellor.

      On the downside, you'd have to look down for people to see if it made a cool pattern.

      On the unrealistic expectations side, if you could pedal really really fast and had a strong chin strap, you could fly around the room.

  • The American Society of Civil Lawyers "Suing The Pants Off^w^w^w Everybody Since 1969"
  • The real question: can you use it to decapitate zombies? Because if not, phbbt, don't waste my time.
  • 1. Propeller-powered tricycle. -DONE-
    2. Button to order pizzas in an emergency. -DONE-
    3. Empty Bathroom Stall internet alert system. -DONE-
    4. Sledgehammer/Bowling Pin sharpener.
    5. Validating/Confirming Scientology.
    6. Wind Turbines for delivering green power to moon bases.
    7. Candle powered gasoline pump, for pumping gas during power outages.
    8. Knee pads so people can chew gum safely while they walk.
    9. Submarine with a screen door.
    10. Solar Powered flashlight.
    11. Bathroom Webcams.

    One would think that with the
    • I suppose that's a passable list, at least after that guy from Duke stole the beer-launching fridge. I know that there are a great many people who are interested in the bathroom webcams, especially if they are small and hard to detect.

      With a little more seriousness, a material that allows air to pass at 1 atmosphere of pressure but doesn't allow water to pass regardless of pressure would be pretty cool.
  • "Whirling Twirling Propeller sTrike"
  • Did you all forget about the Gossamer Albatross [wikipedia.org]?

  • From TFA.... (Score:5, Funny)

    by argStyopa ( 232550 ) on Wednesday July 04, 2007 @05:11PM (#19747379) Journal
    "I spend a month a year working on a commercial fishing boat with a loud diesel engine, and the greatest sound in the world is to hear it turn off," says Damon Vander Lind, the creator of a soothingly quiet trike"

    As opposed to a normal trike, which operates with ear-shattering volume?
  • I looked through the other entries besides the "winning" propeller bike, the last one being a "Dog-powered" scooter. They have a large frisky dog hooked up to it, on the side, so the driver can steer the scooter, rather than give commands to the dog. Looks ok, if we can use dogs to power sleds, then this one would do also. Only problem is when the dog goes after a cat, then you are in for a wild ride.
  • ...can he control it with Linux?
  • Uh, yeah - this was about a year of Bryan Allen, Paul, Tyler, and Parker MacCready's time before the Gossamer Condor left the ground.

    Please tell me 2.0 will have a cage around the fan.

  • Nice (Score:2)

    by flink ( 18449 )
    He should totally join SCUL [scul.org].
  • Why doesn't this genius invert the propeller and add a sail in front of the bike ? It would surely be even more efficient...

  • They made motor powered versions on Scrapheap Challenge [channel4.com] a while back.

Slashdot Top Deals

Our OS who art in CPU, UNIX be thy name. Thy programs run, thy syscalls done, In kernel as it is in user!

Close