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Gyrostabilized Unicycle

Twin horizontally counter-rotating gyro stabilized unicycle
  (+2, -3)
(+2, -3)
  [vote for,

Twin horizontal counter rotating gyro stabilized powered unicycle/personal transportation

Think Segway unicycle or Bombardier Embrio, or but different operating principles.

I was thinking about gyros, not the sandwich, but I love those too, and came up with this idea… Lamberger, tzatziki sauce, wait back to the original idea…

Start with an electric motor/generator (gyro motor) driving a horizontal gyro/flywheel and the sun gear of a planetary gear drive. The planet gear has a brake and is attached to a second reversible motor (steering impulse motor) that is usually not turning. The ring gear is attached to another gyro, so the planetary gears make the two gyros turn at the same speed in opposite directions as long as the second motor doesn’t turn. Now place the entire assembly inside a larger hub driven wheel, controlled by a third reversible electric motor (drive motor). The two counter rotating gyros should keep their rotational axis mostly vertical because rotational force will cause precession in each rotor and the two processional forces should cancel each other, as long as the assembly doesn’t break. Obviously consistent rotational force will still rotate the assembly, but I’m hoping they will all cancel out or be minimal.

So add in batteries and basic speed controllers for the motors to control the speed and steering by wire and you are done. Since the gyro assembly is vertical the single driven wheel should be able to move forward and back when powered by the drive motor. By spinning the steering impulse motor, the vehicle should be able to turn left and right. If the gyro axis goes too far off vertical, the batteries could be shifted as ballast to bring it back slowly.

I think this system would make a good base for a robot or as a Segway replacement especially if the regenerative braking is stored in the gyro.

PS I'm pretty sure the Embrio has a single gyro which is coaxial with the drive wheel and relies on Segway like tech to keep it verticle, such as when you hit the brakes it leans you back before applying brakes.

MisterQED, Nov 30 2007

Embrio http://www.diseno-a...mbadier_embrio.html
[MisterQED, Nov 30 2007]

robotic unicycle http://en.wikipedia...ki/Robotic_unicycle
[JesusHChrist, Dec 01 2007]

Clostest bake from [JesusHChrist] link http://www.mrl.nyu....e/rosie-sketch.html
[MisterQED, Dec 01 2007]

Demo that requires password http://demoroom.phy...html/demos/252.html
[MisterQED, Dec 01 2007]

Double Wheel Gyroscope Video http://lecturedemo....ble-Wheel-Gyroscope
No password required. [baconbrain, Dec 01 2007]


       hell, you have my vote till I take on water and apply logic.
po, Nov 30 2007

       Two wheels good...one wheel baaaad.
4whom, Dec 01 2007

       Somebody tried to explain to me that two counter-rotating gyros cancel each other out. I quote:   

       "This is basic physics: If you're just talking about one axis, you add up the angular momenta as scalar quantities. So much positive and an equal amount negative, and the sum is zero. If you have zero angular momentum, you can twist the object as if there were no flywheels in it. (There will still be forces created on the bearings and the support structure, but these will be internal to the spacecraft.)" - [ldischler]   

       The Embrio is totally vaporware. The person who sculpted it may have had no clue as to how to make it work.   

       I've been kicking around a one-wheel motorcycle control concept for quite a few years now. When I first saw the Embrio, I thought they'd figured it out, but I don't see it in the sculpture.   

       The concept is simple enough. Build a very strong stabilizing gyro (I thought two counter-rotating gyros would work) with a vertical axis, and clamp the handlebars to the gyro housing. Pivot the housing on a fore-and-aft axis so the bars can tilt it relative to the vehicle, which leans the thing into corners.   

       Put the gyro/handlebars on a longer vertical arm that pivots back-and-forth on the front of the vehicle. Fasten the throttle and brake cables to the base of the gyro arm. When the rider pushes on the gyro, it stays vertical, so the body of the vehicle leans back--and the brake cable gets pulled. When the rider pulls on the handlebars, the body goes forward and the throttle is pulled open.   

       At very low speeds, a set of brakes touch the two counter-rotating gyro wheels to pivot the vehicle left and right.
baconbrain, Dec 01 2007

       I'm working on the counter rotating gyro physics, unless I get a login for the movie at (link), or I just brake down and build one. I expect that their processional forces will cancel but you will still be left with a system with an artificially large moment of inertia to oppose rotation perpendicular to the axis of the spins.
MisterQED, Dec 01 2007

       I haven't found a decent description of the Embrio, but from the written decriptions I think I could reverse engineer the ideas: A single driving wheel (obvious from picture), a single gyro coaxial with driving wheel and rotating in the same direction as the drive wheel would when moving forward. The prop wheel is necessary to allow the gyro to be spun up and for parking. Once the gyro is spinning the driver can lean to the left and procession of the gyro will turn the vehicle to the left, and so on for leaning to the right. For and aft stability is provided by same system as Segway (inverted pendulum stability). The reason it will never be built is the same reason Segway had to recall all the Segways, in the case of electrical shutdown the vehicles wil crash. This happened on several Segways whose owners let the batteries run too low.
MisterQED, Dec 01 2007

       Well the linked video kills most of this idea, so I'm really back to the drawing board. I guess it was only half baked.
MisterQED, Dec 01 2007


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