Unicycle

A unicycle is a one-wheeled human powered vehicle. Unicycles are similar to, but less complex than, bicycles.

Contents

1 Construction
2 Riding
3 Extreme Unicycling
4 History
5 Theory
6 Recent developments
7 Unicycle Sports
8 Variations
9 See also
10 External links

Construction

Unicycles are composed of a few key parts: the wheel, which includes the tire, tube, rim, spokes, hub and axle; the cranks and pedals; the frame; the seatpost; and the saddle. The wheel is the main part of the unicycle; it is usually a bicycle wheel rim and spokes with a special hub that doesn't freewheel, which means the axle can't turn independently of the hub. This makes it so the rotation of the cranks directly control the rotation of the wheel. This is called direct drive. The frame sits on top of the axle, and cranks attach to the ends of the axle. The seatpost links the frame to the saddle.

Some modern unicycles use gears in the hub to increase riding distance, but the basic construction remains the same; the seat is located on the frame and the frame sits above the wheel.

Some taller unicycles, called giraffes, have the pedals and cranks some distance above the wheel, and are driven through a chain.

Riding

Riding a unicycle typically takes between 5 and 10 hours of practice time to learn to ride forwards with some control, and several more hours to turn, unless one has an inherent natural ability for riding one. Mastery of the skill however takes a lifetime as there are always new things to learn. At slower speeds steering motions need to be exaggerated to achieve the same angle of turn as at higher speed. The biggest problem for beginners is mounting without leaning on something (or someone) for support. Being able to mount without help is called "freemounting". Freemounting can take a number of days to learn; because of the number of different mounts, it can take a long time to learn them all.

"Idling" happens when a unicyclist maintains position by moving the pedals forwards and backwards between the 5:00 and 7:00 positions.

Balancing a robotic unicycle or a eunicycle forms an interesting problem in control theory.

Extreme Unicycling

In the last 10 years, unicyclists have taken unicycles out of the traditional parade, gym, or circus setting and have created new areas of unicycling. These areas can be described as:

More information can be found at [extremeunicycling.com]

History

Unicycles are thought to descend from the penny-farthing bicycles of the late 19th century. These bicycles had a large wheel in front, to which the pedals were attached, and a much smaller wheel behind for balance. When these bicycles hit a bump, or the rider attempted to slow suddenly, the rear wheel would come off the ground, forcing the rider to balance on one wheel. Early unicycle photographs, which show unicycles with very large wheels, support this explanation.

The earliest large wheel unicycles had a wheel, frame and handlebars, instead of a wheel, frame and seat. Ironically, now that a wheel, frame and seat is the standard format, some manufacturers have started to sell wheel, frame and handlebar unicycles as a novelty.

Unicycles have long been a component of traditional circus performance, often with refinements such as juggling while riding, or riding across a tightrope.

More recently, people have started to do more things on unicycles. There are a number of forms of 'extreme' unicycling. See below.

Theory

A unicycle is a form of inverted pendulum. It is also a nonholonomic system because its outcome is path-dependent.

Recent developments

In recent years unicycles have gained a following as a means of everyday transport. Unicycling has also gained popularity as a sport. The annual national NAUCC and bi-annual world championship UNICON hold Unicycle races. Riding a unicycle in off-road conditions is known as mountain unicycling, commonly called MUni. In unicycle trials the unicyclist aims to negotiate a series of obstacles, usually done by hopping, without any part of the rider touching the ground or using the hand to grasp onto an obstacle. Freestyle Unicycling contains a style of tricks similar to those seen in skateboarding, aggressive in-line skating, BMX, and freestyle biking including jumps, spins, and grinds. The newest style of riding is street unicycling. It is a mix of unicycle trials and freestyle unicycling. It consists of stair riding, jumps, grinds, spins, and rail riding usually on urban obstacles.

Unicycle Sports

Unicycle Hockey (or UniHoki) is a growing niche sport, with 5 members on each team and played with ice-hockey sticks and a street hockey ball or a deadened tennis ball as favoured by the Germans (some clubs have been known to use a puck). A league operates in Germany/Switzerland; in other countries such as Great Britain clubs typically meet and play individually, and competitively at Uni and club meets and conventions. The world championships sometimes take place at the biannual UNICON event.

International Unicycle Hockey rules: http://www.mpch-mainz.mpg.de/~sander/uni/iuf_03e.html

There are also other sports played on a unicycle, such as unicycle basketball.

Variations

Giraffe unicycles are tall, usually chain-driven unicycles. The exceptions are some very tall unicycles which require "fixed" cranks instead of chains, since a certain amount of slack is unavoidable once the chain exceeds a certain length. This slack can cause slippage and loss of control which can be a serious problem on a very tall unicycle. You can create a giraffe unicyle from a normal bicycle by taking the front wheel and handlebars off and sitting on the part of the frame that the handlebar stem usually fits into. This will only work with a fixed wheel bicycle. Riding a giraffe is a skill that should not be attempted unless you are good at riding a unicycle. The first time you graduate from a traditional unicyle to the giraffe there are two main differences: (1) A giraffe unicycle is harder to mount, as it is higher, (2) but much easier to balance because you have more reaction time in which to compensate for loss of balance.
Mountain unicycles or munis: unicycles made for the sport of mountain unicycling, usually with thicker wheels.
Kangaroo unicycles: unicycles with an off-center wheel and cranks that face the same direction.
Trials unicycle: unicycle meant for drops and hops, usually with a smaller wheel diameter, for more agility.
Ultimate wheel: a unicycle with no frame or seat, just a wheel, cranks, and pedals.
Impossible wheel:(Also known as a BC wheel) a wheel with pegs or metal plates sticking out for the rider to stand on.
Monocycle (also known as a monowheel) : a large wheel in which the rider sits inside (like a hamster wheel) and either pedals an internal drive or is motorized. It is not plagued by the normal unicycle balance problems because of the greater gyroscopic properties and lower center of mass.
Eunicycle : a computer-controlled self-balancing unicycle.
Coaster Uni: a unicycle where the hub freewheels, giving a cross between a traditional unicycle (where one pedals to maintain forward velocity and balance) and an impossible wheel (where instead of standing on pegs or platforms, the rider stops pedalling and stands on the pedals.)
Multi-wheeled unicycle: Still a unicycle since the wheels are stacked on top of each other so only one touches the ground. The wheels are linked together by chains or friction.
A quick list of other variations: Tandem, Recumbent, Hydraulic Giraffe, Unibike, Suicycle, Motorized unicycle [link]

External links

Wikibooks has a manual, textbook or guide to this subject:

[[wikibooks:|]]

[[wikibooks:The Unicyclopedia|The Unicyclopedia]] - The Encyclopedia of Unicycling
[Unicycle.com] - An excellent source for unicycles
[Unicyclist.com] - An excellent forum for information about unicycles
[Unicyclist.org] - Huge archive of clips on unicycle skills
[Syko Productions] - Produces extreme unicycling videos
[Unicycle Jester] - Homepage of Jess Riegel, trials/muni unicyclist
[One Wheel] - Muni and Steet Videos From Wisconsin
[International Unicycling Federation]
[einradfreak.at] - Unicycling Page from Austria
[Enhjulingsfolket] - Unicycling in Scandinavia
[The Unicycle Page]
[Union of UK Unicyclists]
[IUF Skill Levels]
[Unicycling Society of America]
[Swiss Unicycling Federation]
[The French Federation of Unicycling]
[Mike Hinson's collection of links on the physics of unicycles]
[International Unicycle Hockey Homepage]
[Unicon 12]
[German Unicycle Hockey League]
[Corea(South Korea) Unicycling Association - English Page]
[Gauteng Unicyclist Society, GUS for short] - Unicycling in South Africa
[Unicycle site with miscellanceous photos and information]
[Canadian Distributor of Unicycles]

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