Unicycle
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A unicycle is a one-wheeled human powered vehicle. Unicycles are similar to, but less complex than, bicycles.
[edit] Construction
Unicycles are composed of a few key parts: the wheel (which includes the tire, tube, rim, spokes, hub and axle), the cranks, pedals, fork-style frame, seatpost, and saddle (the seat of the unicycle). The wheel is usually like a bicycle wheel type with a special hub designed so the axle is a fixed part of the hub. This means the rotation of the cranks directly controls the rotation of the wheel (called direct drive). The frame sits on top of the axle bearings, while the cranks attach to the ends of the axle. The seatpost links the frame to the saddle. Leonardo Da vinci was the first person to come up with this idea.[citation needed]
There are many different types of unicycles, which can include (but are not limited to): freestyle unicycles, trial unicycles, MUnis, giraffes, and long distance unicycles, which all have special components unique to that type of unicycle. See below for more detailed descriptions.
[edit] History
The unicycle's history began with the invention of the bicycle. Comte De Sivrac was said to have first developed bicycles during the late eighteenth century. His device, called a célérifère, was a wooden horse that had two wheels joined by a wooden beam. However, this 'invention' was actually a hoax created by a French historian just after the French defeat in 1870 (the truth remained hidden until the second half of the twentieth century). Germany’s Baron von Drais really created the design: a wooden horse that had two wheels joined by a wooden beam and a steering mechanism, and introduced his Draisienne or Hobby Horse in 1818. Kirkpatrick Macmillan, a Scottish blacksmith, added cranks and pedals to the front wheel in 1839, and called it the Velocipede. The first mass-produced riding machine, the Michaux Velocipede, was designed in 1863. In 1866, James Stanley invented a unique bicycle called the Penny Farthing with a very large front wheel and a small rear wheel. It is this vehicle that is thought to be the inspiration for the unicycle.
One theory of the advent of the unicycle is based on the popularity of the Penny Farthing during the late nineteenth century. Since its pedal cranks were connected directly to the front axle, the rear wheel would go up in the air and the rider would be moved slightly forward. This likely prompted riders to see how long they could ride with the back wheel in the air and the unicycle was born. Evidence for this theory of development can be found in pictures from the late nineteenth century that show unicycles with large wheels.
Since the unicycle requires a greater degree of skill to ride than a bicycle, many people who could ride them became entertainers. Over the years, unicycle enthusiasts have inspired manufacturers to create new designs such as seatless (the ultimate wheel) and tall (giraffe unicycle) unicycles. During the late 1980s some extreme sportsmen took an interest in the unicycle and off-road unicycling (MUni) was born.
[edit] Riding
Learning to ride a unicycle takes patience. It can take from 5 to 15 hours to learn to ride. When learning to ride a helmet should be worn. The helmet can be eliminated as skill is developed, but is still recommended for trials, MUni, and other more dangerous types of riding. Find a flat hard surface to ride on and find someone or something to hold onto. One of the safest thing to hold on to are two chairs placed facing outwards on eitherside of you. Practice rocking back and forth to get a feel for how the pedals affect your balance. Often a doorway in a gymnasium or a porch are good areas to practice. When no longer completely dependent on the railing or wall for balance, try riding foward, keeping weight slightly ahead of the wheel. It can be frustrating, but success will come with practice.
[edit] Extreme Unicycling
Recently, unicycling has gained popularity as a sport, and as a general means of transport. 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:
- Unicycle trials: Trials involves riding over obstacles of any sort, either in natural terrain or in an urban environment. The challenge relates to technical difficulty over short distances, and the objective is to use any riding techniques necessary to ride up, over, or down an obstacle without falling.
- Mountain unicycling (Muni): Combines cross-country and trials challenges, where the objective is to ride technically difficult terrain over some distance. Extreme sport videos and films typically show Muni as primarily descents of difficult terrain, but the term also includes difficult uphill riding. The other purpose of this venture is to practice leaps using the wheel pressure to propel yourself up to a rock, or up a slope.
- Flatland : The purpose of flatland (also known as freestyle) is to ride a unicycle in different ways, collectively referred to as “freestyle tricks”. There are thousands of different ways to ride a unicycle, but the most popular tricks have been grouped into categories called the “10 skill levels of unicycling”. Flatland is typically done indoors in a gymnasium or outside on pavement where the terrain is smooth and predictable.
- Street unicycling: Combines Trials and Freestyle techniques, and is typically done in urban areas. The objective is to perform freestyle tricks on obstacles. The overall difficulty relates not only to the difficulty of the obstacles but also to the difficulty of the tricks. This is different from pure trials because just riding over obstacles is not the ultimate objective; rather, the obstacles are used as props to set up the tricks.
More information can be found at extremeunicycling.com
[edit] Main Types of Unicycles
- Freestyle unicycle
- Generally used for flatland skills and routines. Usually has a relatively high seatpost, a narrow saddle, a squared fork (used for one-footed tricks), and cotterless cranks, as they do not need to withstand too much pressure. These unicycles are used similarly to flatland bicycles. Some examples of a freestyle unicycle include: Miyata, Nimbus, Schwinn, and Semcycle brands. Prices can range from less than $100 USD to over $300 USD. Wheel size is usually 20 inches, but smaller riders may use 16-inch unicycles. Some people prefer 24-inch wheels. A freestyle unicycle is stronger than other types of unicycles.
- Trials unicycle
- Designed for unicycle trials, trials unicycles are stronger than standard unicycles in order to withstand the stresses caused by jumping, dropping, and supporting the weight of the unicycle and rider on components such as the pedals and cranks. A recent development in trials unicycles is splined cranks, a feature that is very useful and somewhat expensive. Many trials unicycles also have wide, 19- or 20-inch, knobby tires to absorb some of the impact on drops. For more info, see the trials unicycle page.
- MUnis or Offroad Unicycles
- MUni is the shortened phrase for mountain unicycling. Munis have many of the same components as trials unicycles, but have a few key differences. Usually, the tire diameters on mountain unicycles are either 24 or 26 in., allowing the rider to more easily roll over obstacles such as roots and rocks. The seat is also thicker and more comfortable on MUnis to compensate for the rough terrain. Brakes are sometimes used for steep descents. KH unicycles and Schlumpf Innovations are currently working together to make the world's first geared MUni.
- Touring unicycles
- Used for long distances, these unicycles are specially made to cover distances. They have a large wheel diameter, between 26 and 36 in., so more distance is covered in less pedal rotation. A 36" unicycle made by the Coker company started the big wheel trend. Some variations on the traditional touring unicycle include the 'Schlumpf GUni' (geared unicycle), which uses a unique two-speed internal fixed-geared hub. Larger direct-drive wheels tend to have shorter cranks to allow for easier cadence and more speed. Geared wheels, with an effective diameter larger than the wheel itself, tend to use longer cranks for control, as the speed comes from the gear ratio not the wheel itself. Modern unicyclists routinely cover distances unheard of just a few decades ago.
[edit] Variations
- Giraffe unicycle: a tall unicycle, usually chain-driven (but includes Multi-wheel unicycles).
- Geared unicycle (aka GUni): a unicycle whose wheel rotates faster than the pedal cadence. Used for distance riding and racing.
- Multi-wheeled unicycle: A unicycle with more than 1 wheel, stacked on top of each other so only one touches the ground. The wheels are linked together by chains or direct contact with each other.
- Kangaroo unicycle: unicycle that has both the cranks facing in the same direction & the hub off-center. They are so-named due to the rising and falling motion of the rider supposedly resembling the jumping of a kangaroo.
- Ultimate wheel: a unicycle with no frame or seat, just a wheel, cranks, and pedals.
- BC wheel : a wheel with pegs or metal plates connected to the axle for the rider to stand on. These wheels are for coasting and jumping. A purist form of unicycling. There are no cranks.
- Monocycle (or 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, motor driven, self-balancing unicycle.
- Freewheeling unicycle: a unicycle where the hub freewheels, allowing the rider to coast or move forward without pedalling, as a bike would. These unicycles almost 'always' have brakes because they cannot stop the way traditional unicycles do. These unicycles also cannot go backwards.
- A quick list of other variations: Tandem, Recumbent, Hydraulic Giraffe, Unibike, Suicycle, Motorized unicycle [1]
[edit] Theory
A unicycle is a form of inverted pendulum. It is also a nonholonomic system because its outcome is path-dependent. Balancing a robotic unicycle or a eunicycle forms an interesting problem in control theory.
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[edit] See also
- Bicycle and motorcycle physics
- Impossible wheel a.k.a. BC wheel
- Ultimate wheel
- Unicycling
[edit] Unicycle manufacturers
- Coker Tire Company Unicycles
- Koxx One Unicycles
- Kris Holm Unicycles
- LiveWire Unicycles
- Pichlerrad
- Schlumpf
- Semcycle
- Torker Bicycle
- Unicycle.com
- Qu-Ax
[edit] External links
- The Unicyclopedia - The Encyclopedia of Unicycling
- Unicyclist.com - An excellent forum for information about unicycles
- Unicyclist.org - Huge archive of clips on unicycle skills
- International Unicycling Federation
- Unicycle Hockey Video
