A unicycle is a one-wheeled human powered
vehicle. Unicycles are similar to, but less complex than, bicycles. This topic is
covered in a lot more depth at Wikibooks:The Unicyclopedia.
Construction
Unicycles comprise a few key parts: the wheel and hub(axle), the frame, the seat, and cranks and
pedals. The wheel is the main part of the unicycle; it is essentially a bicycle wheel
with a special hub so that the frame and cranks can attach to the side. Unicycles use direct drive, with the crank's rotation
directly connected to that of the wheel, although some modern unicycles are using gears in the hub to increase riding distance.
The frame sits above the wheel, and the seat is located on top of the frame.
Riding
Riding a unicycle typically takes between 10 and 15 hours to learn. Compared to a bicycle, the rider must maintain balance in two dimensions rather than one, and with their slower speeds their
motion has less gyroscopic assistance for maintaining stability.
Balancing a robotic unicycle or a eunicycle forms an interesting problem in control
theory.
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.
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
bi-annual world championship UNICON holds 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 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 hockey
Unicycle Hockey 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, clubs typically meet and play individually, and competitively at Uni and club meets and
conventions. The world championships take place at the biennial Unicon event.
International rules: http://www.mpch-mainz.mpg.de/~sander/uni/iuf_03e.html
Variations
- Giraffe unicycles: tall, chain-driven unicycles.
- Mountain unicycles: unicycles made for the sport of mountain unicycling.
- Kangaroo unicycles: unicycles with an off-center wheel and
cranks that face the same direction. The rider of a kangaroo unicycle appears to be hopping about like a kangaroo, hence the name.
- Ultimate wheel: a unicycle
with no frame or seat, just a wheel, cranks, and pedals.
- Impossible wheel: a wheel with pegs sticking out for the rider
to stand on. Theoretically, this works like log-rolling.
- 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, Motorized, Suicycle
- Monowheel (also known as a monocycle) : 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.
External links
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