Monowheel
Encyclopedia
A monowheel is a one-wheeled single-track vehicle
similar to a unicycle
. However, instead of sitting above the wheel, the rider sits either within it or next to it. The wheel is a ring, usually driven by smaller wheels pressing against its inner rim. Most are single-passenger vehicles, though multi-passenger models have been built.
Pedal-powered monowheels were built in the late 19th century; most built in the 20th century have been motorized. Some modern builders refer to these vehicles as monocycles, though that term is also sometimes used to describe motorized unicycles.
Today, monowheels are generally built and used for fun and entertainment purposes, though from the 1860s through to the 1930s, they were proposed for use as serious transportation.
A change in direction can be effected in several ways including:
. A variant was proposed that placed two riders outside of the wheel itself, with one person on each side to provide for balance.
An electric monowheel called Dynasphere
was tested in 1932 in the United Kingdom
.
One interesting variant called a RIOT wheel
was presented at Burning Man
in 2003. It involves the passengers sitting in front of the wheel and being balanced by a heavy counterweight inside the wheel. Rather than the typical ring drive, this vehicle is powered through a sprocket
attached to the spokes.
A company in the Netherlands began taking custom orders of a monocycle configured variant called the Wheelsurf in 2007.
A related vehicle is the diwheel or the dicycle
, in which the rider is suspended between or inside of a pair of large wheels placed side by side. An example of this would be the character Axel from the Twisted Metal series of video games published by Sony.
In 1971, an American inventor named Kerry McLean built his first monocycle (aka monowheel). In 2000, he built a larger version, the McLean Rocket Roadster powered by a Buick V-8 engine, which subsequently crashed in 2001 during the initial test run. Fortunately, McLean survived and proceeded to build over 25 different variations of his version of the monocycle, from pedal powered models, 5HP models, all the way up to V8 powered models.
In 2010, Nokia utilized two of McLean's monocycles in their commercials promoting the new Nokia SatNav smartphone.
McLean's latest creation, the 2011 McLean V8 Drag Wheel, of which the wheel itself was machined out of a single piece of high-strength aircraft grade aluminum billet, was completed in 2011.
They are noticeably more common in Japanese anime
and manga
.
Single-track vehicle
A single-track vehicle is a vehicle that leaves a single ground track as it moves forward. Single-track vehicles usually have little or no lateral stability when stationary but develop it when moving forward or controlled...
similar to a unicycle
Unicycle
A unicycle is a human-powered, single-track vehicle with one wheel. Unicycles resemble bicycles, but are less complex.-History:One theory of the advent of the unicycle stems from the popularity of the penny-farthing during the late 19th century...
. However, instead of sitting above the wheel, the rider sits either within it or next to it. The wheel is a ring, usually driven by smaller wheels pressing against its inner rim. Most are single-passenger vehicles, though multi-passenger models have been built.
Pedal-powered monowheels were built in the late 19th century; most built in the 20th century have been motorized. Some modern builders refer to these vehicles as monocycles, though that term is also sometimes used to describe motorized unicycles.
Today, monowheels are generally built and used for fun and entertainment purposes, though from the 1860s through to the 1930s, they were proposed for use as serious transportation.
Steering
In a two-wheel mode of transportation, two systems (wheels) affect motion. Typically one wheel provides the force to control speed, while the other handles changes in direction: steering. For a monowheel, both direction and speed are controlled through the same physical apparatus; this generally makes steering more difficult. In a majority of systems, change in direction is affected by the rider shifting its weight, or in the sudden movement creating a shearing force between a handhold and the axis that the driver is settled on. Better control can usually be achieved at slower speeds. Because of the steering problem, monowheels have never caught on as a widely accepted mode of transportation.A change in direction can be effected in several ways including:
- Leaning. The most common steering solution is that the rider must lean towards his intended direction of travel to turn, and then centralize his weight again once the turn is complete.
- Turning a gyroscopeGyroscopeA gyroscope is a device for measuring or maintaining orientation, based on the principles of angular momentum. In essence, a mechanical gyroscope is a spinning wheel or disk whose axle is free to take any orientation...
to provide turning force. - Outboard skids to provide frictionFrictionFriction is the force resisting the relative motion of solid surfaces, fluid layers, and/or material elements sliding against each other. There are several types of friction:...
drag on one side. - At speeds faster than a walk, lightly dragging a foot on the ground will cause the wheel to lean to the opposite side. Drag the other foot to bring it back upright.
- Small wheels used for steering, either one to each side or a single unit either in front of or behind the vehicle. It is a matter of debate as to whether such a vehicle would still properly be called a monowheel.
- Steerable propellerPropellerA propeller is a type of fan that transmits power by converting rotational motion into thrust. A pressure difference is produced between the forward and rear surfaces of the airfoil-shaped blade, and a fluid is accelerated behind the blade. Propeller dynamics can be modeled by both Bernoulli's...
s, which could provide both steering and power to move the vehicle. It has been noted that having a propeller operating near pedestrians would likely be quite unsafe. - Steerable tail surfaces, similar to those on airplanes. This solution would not work at low speeds.
Other issues
- Limited horizontal stability. A single wheel can fall over, unless it is quite wide or has some form of active stabilization, such as a gyroscope. Some designs have used outrigger skids or small wheels to address this. In many one-person designs, being at a stop requires the driver to put their feet on the ground, the same way as on a motorcycleMotorcycleA motorcycle is a single-track, two-wheeled motor vehicle. Motorcycles vary considerably depending on the task for which they are designed, such as long distance travel, navigating congested urban traffic, cruising, sport and racing, or off-road conditions.Motorcycles are one of the most...
. - Limited capacity. Monowheels tend to be larger than a carAutomobileAn automobile, autocar, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor...
of similar carrying capacity. Most have been kept small by being built to carry only one rider and with little or no space for baggage. - Risk of "gerbiling". In most designs, if the driver acceleratesAccelerationIn physics, acceleration is the rate of change of velocity with time. In one dimension, acceleration is the rate at which something speeds up or slows down. However, since velocity is a vector, acceleration describes the rate of change of both the magnitude and the direction of velocity. ...
or brakeBrakeA brake is a mechanical device which inhibits motion. Its opposite component is a clutch. The rest of this article is dedicated to various types of vehicular brakes....
s too hard, it is possible that the force applied overcomes the force of gravity keeping the rider at the bottom of the wheel, sending the rider spinning around the inside of the wheel. This is known as gerbiling, because it has some similarity to the situation of a gerbilGerbilA gerbil is a small mammal of the order Rodentia. Once known simply as "desert rats", the gerbil subfamily includes about 110 species of African, Indian, and Asian rodents, including sand rats and jirds, all of which are adapted to arid habitats...
running too quickly inside of a hamster wheelHamster wheelMost wheels are constructed of steel or plastic, both with advantages and problems. Solid plastic wheels are safer for some types of pets, such as hamsters and hedgehogs, because the space between rungs is solid and the animal's feet or legs cannot get stuck between rungs, an injury risk in steel...
. - Visibility issues. In driver-inside designs, the rider is always facing the inner rim of the wheel, which can obstruct the view of oncoming hazards.
Variants and related vehicles
There have been many proposals for variants or uses, such as a horse-drawn monowheel or a monowheel tankTank
A tank is a tracked, armoured fighting vehicle designed for front-line combat which combines operational mobility, tactical offensive, and defensive capabilities...
. A variant was proposed that placed two riders outside of the wheel itself, with one person on each side to provide for balance.
An electric monowheel called Dynasphere
Dynasphere
The Dynasphere was a monowheel electric vehicle invented in 1932 by Dr. J. A. Purves from Taunton, Somerset, UK. It had 2.5 horse power and once attained a speed of 25 mph....
was tested in 1932 in the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
.
One interesting variant called a RIOT wheel
RIOT wheel
A RIOT wheel is a one-wheeled vehicle, or monowheel. Housing a motor and counterweight inside a giant wheel, the driver sits on a platform that extends out in front of the device.By moving the wheel's center of gravity forward, the wheel turns...
was presented at Burning Man
Burning Man
Burning Man is a week-long annual event held in the Black Rock Desert in northern Nevada, in the United States. The event starts on the Monday before the American Labor Day holiday, and ends on the holiday itself. It takes its name from the ritual burning of a large wooden effigy on Saturday evening...
in 2003. It involves the passengers sitting in front of the wheel and being balanced by a heavy counterweight inside the wheel. Rather than the typical ring drive, this vehicle is powered through a sprocket
Sprocket
A sprocket or sprocket-wheel is a profiled wheel with teeth, cogs, or even sprockets that mesh with a chain, track or other perforated or indented material. The name 'sprocket' applies generally to any wheel upon which are radial projections that engage a chain passing over it...
attached to the spokes.
A company in the Netherlands began taking custom orders of a monocycle configured variant called the Wheelsurf in 2007.
A related vehicle is the diwheel or the dicycle
Dicycle (vehicle)
A dicycle is a vehicle with two wheels side by side, unlike single-track vehicles such as motorcycles and bicycles, which have one wheel followed by another....
, in which the rider is suspended between or inside of a pair of large wheels placed side by side. An example of this would be the character Axel from the Twisted Metal series of video games published by Sony.
In 1971, an American inventor named Kerry McLean built his first monocycle (aka monowheel). In 2000, he built a larger version, the McLean Rocket Roadster powered by a Buick V-8 engine, which subsequently crashed in 2001 during the initial test run. Fortunately, McLean survived and proceeded to build over 25 different variations of his version of the monocycle, from pedal powered models, 5HP models, all the way up to V8 powered models.
In 2010, Nokia utilized two of McLean's monocycles in their commercials promoting the new Nokia SatNav smartphone.
McLean's latest creation, the 2011 McLean V8 Drag Wheel, of which the wheel itself was machined out of a single piece of high-strength aircraft grade aluminum billet, was completed in 2011.
Fiction
- Iain M. BanksIain BanksIain Banks is a Scottish writer. He writes mainstream fiction under the name Iain Banks, and science fiction as Iain M. Banks, including the initial of his adopted middle name Menzies...
' novel Against a Dark BackgroundAgainst a Dark BackgroundAgainst a Dark Background is a science fiction novel by Scottish writer Iain M. Banks, first published in 1993.It was his first science fiction novel not to be based or set in the Culture.-Plot summary:...
contains a rare instance of a monowheel as an important feature of a fictional work. - Stanislav Lem's novel EdenEden (novel)Eden is a 1959 science fiction novel by Stanisław Lem. It was first published in English in 1989 .-Plot:A starship crew – a captain, a doctor, an engineer and a chemist, a physicist and a cyberneticist – crash land for an unknown reason on an alien world they call Eden...
features motorized variants of the monowheel. - Robert A. HeinleinRobert A. HeinleinRobert Anson Heinlein was an American science fiction writer. Often called the "dean of science fiction writers", he was one of the most influential and controversial authors of the genre. He set a standard for science and engineering plausibility and helped to raise the genre's standards of...
's novel The Cat Who Walks Through WallsThe Cat Who Walks Through WallsThe Cat Who Walks Through Walls: A Comedy of Manners is a science fiction novel by Robert A. Heinlein published in 1985. Like many of his later novels, it features Lazarus Long and Jubal Harshaw as supporting characters.-Plot summary:...
features a gyroscope stabilized lunar "doughnut" craft with a driver on one side and a turret gunner on the other, that can bounce over lunar obstacles. - Amazing Three, known in Japan as Wonder 3 (ワンダー3, Wandā Surī?) or W3, features three agents from outer space who travel in a tire-shaped vehicle called the Big Wheel, which can travel at enormous speeds on both land and water (and, with modifications, through the air).
- In South ParkSouth ParkSouth Park is an American animated television series created by Trey Parker and Matt Stone for the Comedy Central television network. Intended for mature audiences, the show has become famous for its crude language, surreal, satirical, and dark humor that lampoons a wide range of topics...
episode "The Entity"The Entity (South Park)"The Entity" is the eleventh episode of the fifth season of the animated television series South Park, and 76th episode of the series overall. "The Entity" originally aired in the United States on November 21, 2001 on Comedy Central. This episode introduces Kyle's cousin Kyle...
Mr Garrison makes a gyroscopeGyroscopeA gyroscope is a device for measuring or maintaining orientation, based on the principles of angular momentum. In essence, a mechanical gyroscope is a spinning wheel or disk whose axle is free to take any orientation...
-stabilized, turbine-engine-propelled device resembling the monowheel, called "IT" ' onMouseout='HidePop("19851")' href="/topics/Segway_PT">SegwaySegway PTThe Segway PT is a two-wheeled, self-balancing transportation machine invented by Dean Kamen. It is produced by Segway Inc. of New Hampshire, USA. The name "Segway" is a homophone of "segue" while "PT" denotes personal transporter....
), with a rather uncomfortable user interface. - In the FrenchFranceThe French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
animated television series Code LyokoCode LyokoCode Lyoko is a French animated television series created by Thomas Romain and Tania Palumbo. The series centers on boarding school students Jeremie, Ulrich, Yumi, and Odd who travel to the virtual world of Lyoko to fight against multi-agent computer program XANA with Aelita, a being originally...
, the character Ulrich Stern uses a "monocycle" (basically a motorized unicycle) as his vehicle of choice on Lyoko. Ulrich's "Overbike" is capable of flightFlightFlight is the process by which an object moves either through an atmosphere or beyond it by generating lift or propulsive thrust, or aerostatically using buoyancy, or by simple ballistic movement....
and land travel. - In Star Wars Episode III: Revenge of the SithStar Wars Episode III: Revenge of the SithStar Wars Episode III: Revenge of the Sith is a 2005 American epic space opera film written and directed by George Lucas. It is the sixth and final film released in the Star Wars saga and the third in terms of the series' internal chronology....
, General GrievousGeneral GrievousGeneral Grievous is a fictional character in the Star Wars universe, an antagonist in Star Wars Episode III: Revenge of the Sith. He was voiced by Matthew Wood...
uses a monowheel. - In the animated series Star Wars: DroidsStar Wars: DroidsStar Wars: Droids, also known as Droids: The Adventures of R2-D2 and C-3PO, was an animated television series that featured the exploits of R2-D2 and C-3PO, the droids who have appeared in all six Star Wars films...
the young miner Jann Tosh owns a similar wheel bike. - In the animated series and action figure line Spiral ZoneSpiral ZoneSpiral Zone was a 1987 American science-fiction animated series produced by Atlantic-Kushner-Locke. Based in part from a toy line made by Japanese company Bandai, the series focus on an international group of soldiers fighting to free the world from a scientist who controls much of the Earth's...
, Colonel Dirk Courage rode the Rimfire, a large monowheel with an attached cannon. - The Mowercycle of ChaoticChaotic (TV series)Chaotic is an American-Canadian animated fantasy television series produced by 4Kids Entertainment and animated by Bardel Entertainment. It is based on the Danish trading card game of the same name. Much of the plot is based on the original storyline of the Danish trading card game.-Premise:Chaotic...
is a monowheel with gripping teeth that also act as sawSawA saw is a tool that uses a hard blade or wire with an abrasive edge to cut through softer materials. The cutting edge of a saw is either a serrated blade or an abrasive...
teeth. - The War Wheel is a huge, armored battle tank that first appeared in DC's BlackhawkBlackhawk (comics)Blackhawk, a long-running comic book series, was also a film serial, a radio series and a novel. The comic book was published first by Quality Comics and later by DC Comics. The series was created by Will Eisner, Chuck Cuidera, and Bob Powell, but the artist most associated with the feature is Reed...
comic. War wheels were also used in the Justice League (TV series)Justice League (TV series)Justice League is an American animated television series about a team of superheroes which ran from 2001 to 2004 on Cartoon Network. The show was produced by Warner Bros. Animation. It is based on the Justice League of America and associated comic book characters published by DC Comics...
. - In Kirby Super StarKirby Super StarKirby Super Star, known as Kirby's Fun Pak in Europe and as in Japan, is a 1996 platforming video game developed by HAL Laboratory and published by Nintendo for the Super Nintendo Entertainment System video game console. It was first released in Japan on March 21, 1996, in North America on...
, the helper from the wheelie powerup is a monowheel. - A futuristic version of the monowheel is shown in a few episodes of Teenage Mutant Ninja Turtles: Fast Forward.
- The fourth edition of the roleplaying game ShadowrunShadowrunShadowrun is a role-playing game set in a near-future fictional universe in which cybernetics, magic and fantasy creatures co-exist. It combines genres of cyberpunk, urban fantasy and crime, with occasional elements of conspiracy fiction, horror, and detective fiction.The original game has spawned...
features a monowheel called the Horizon-Doble Revolution. - In the videogame Wild Arms 5Wild Arms 5Wild Arms 5, released in Japan as , is the fifth video game in the Wild Arms series of role-playing games. The game celebrates the series' 10th anniversary by featuring cameo appearances of characters from the previous games. Produced by Media.Vision for the Sony PlayStation 2 platform, it was...
the main character Dean obtains a monowheel for faster transportation around world map areas.
They are noticeably more common in Japanese anime
Anime
is the Japanese abbreviated pronunciation of "animation". The definition sometimes changes depending on the context. In English-speaking countries, the term most commonly refers to Japanese animated cartoons....
and manga
Manga
Manga is the Japanese word for "comics" and consists of comics and print cartoons . In the West, the term "manga" has been appropriated to refer specifically to comics created in Japan, or by Japanese authors, in the Japanese language and conforming to the style developed in Japan in the late 19th...
.
- In the OVA series Dirty Pair FlashDirty Pair Flashis a humorous science fiction anime and manga franchise based on the light novel series by Haruka Takachiho.Although it is often said that these are younger versions of the original Lovely Angels Kei and Yuri, in truth this series is an alternate universe telling of Dirty Pair, set in the years...
Mission 3, a young female assassin called Monica drives a Red Futuristic Monowheel. - In Hiroya OkuHiroya Okuis a manga artist who is the creator of Gantz, Zero One and HEN, all of which have been serialized in Young Jump. He is currently working on Phase 3 of Gantz, which began in October 2009...
's mangaMangaManga is the Japanese word for "comics" and consists of comics and print cartoons . In the West, the term "manga" has been appropriated to refer specifically to comics created in Japan, or by Japanese authors, in the Japanese language and conforming to the style developed in Japan in the late 19th...
series GantzGantzis a Japanese manga series written and illustrated by Hiroya Oku. Gantz tells the story of Kei Kurono and his friend Masaru Kato who die in a train accident and become part of a semi-posthumous "game" in which they and several other recently deceased people are forced to hunt down and kill aliens...
, the players are provided with a very fast motorized monowheel (called the Gantz Bike) to evade their alien opponents during a mission later in the story. - In the first episode of Nadia: The Secret of Blue WaterNadia: The Secret of Blue Wateris a Japanese animated television series inspired by the works of Jules Verne, particularly Twenty Thousand Leagues Under the Sea and the exploits of Captain Nemo...
, a protagonist uses one in a rescue of the eponymous character. - In Katsuhiro OtomoKatsuhiro Otomois a Japanese comic book creator, screenwriter and film director. He is best known as the creator of the manga Akira and its animated film adaptation. Otomo has also directed several live-action films, such as the 2006 feature film adaptation of the manga Mushishi.-Biography:Katsuhiro Otomo was...
's film SteamboySteamboyis a 2004 Japanese animated steampunk film, produced by Sunrise, and directed and co-written by Katsuhiro Otomo, his second major anime release, following Akira. The film was released in Japan on July 17, 2004. Steamboy is the most expensive full length Japanese animated movie made to date...
(2004), Ray Steam, the protagonist of the story, uses a steamSteamSteam is the technical term for water vapor, the gaseous phase of water, which is formed when water boils. In common language it is often used to refer to the visible mist of water droplets formed as this water vapor condenses in the presence of cooler air...
-powered monowheel early in the movie. - In the animated adaptation of Venus WarsVenus Warsis a Japanese manga series written and illustrated by Yoshikazu Yasuhiko. It was serialized in the Gakken magazine Nora Comics from 1987 to 1990...
, one-wheeled motorcycles are used both in bloodsport and combat. - Mobile Suit Victory GundamMobile Suit Victory Gundam, is a 1993 Japanese science fiction anime television series. It consists of 51 episodes, and was directed by Gundam creator Yoshiyuki Tomino. The series was first broadcast on TV Asahi and later by the anime satellite television network, Animax, across Japan and later its respective networks...
features the Einrad, a colossal monowheel used as a transport vehicle for the Zanscare Empire's mobile suits. - In Yu-Gi-Oh! 5D'sYu-Gi-Oh! 5D'sis a Yu-Gi-Oh! series which aired in Japan between April 2, 2008 and March 30, 2011, following the previous series, Yu-Gi-Oh! GX, and was succeeded by Yu-Gi-Oh! Zexal, on April 11, 2011...
, the character Jack Atlus uses a monowheel D-Wheel named "Wheel of Fortune" in riding duels. - In Hot Wheels Battle Force 5Hot Wheels Battle Force 5Hot Wheels Battle Force 5 is an American/Canadian 3D CGI television series created by Mattel, Nelvana, and Nerd Corps Entertainment. A two-episode preview aired on the Cartoon Network in the United States on August 24, 2009. In Cartoon Network India it is starting from April 30, 2010 and in Cartoon...
, The Red Sentient Kytren uses The Vyirex which is a gyroscope monowheel (hence the name).
Non-fiction
- In an episode of the BritishUnited KingdomThe United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
television show Scrapheap ChallengeScrapheap ChallengeScrapheap Challenge is an engineering game show produced by RDF Media and broadcast on Channel 4 in the UK. In the show, teams of contestants have 10 hours in which to build a working machine that can do a specific task, using materials available in a scrapheap. The format was exported to the...
, two teams competed to build and race monowheels. - In the Australian Reality TV show Push the Limit a monowheel challenge ended when contestant Kate Siopis fractured her wrist.
- Many monowheels were used in the closing ceremony of the 2008 Beijing Olympics.
Advertising media
- In a 2007 television commercial produced for the drink brand Capri Sun, a boy and a girl are both riding in variants which appear to be manufactured vehicles made of metal and fiberglass (up to the point where they are levitated into the air by a CGI effect).
- In 2010, Nokia utilized two McLean Monocycles in their commercials promoting the new Nokia SatNav smartphone. Multiple versions of the commercial were created and aired throughout the world.
See also
- UnicycleUnicycleA unicycle is a human-powered, single-track vehicle with one wheel. Unicycles resemble bicycles, but are less complex.-History:One theory of the advent of the unicycle stems from the popularity of the penny-farthing during the late 19th century...
- Dicycle (vehicle)Dicycle (vehicle)A dicycle is a vehicle with two wheels side by side, unlike single-track vehicles such as motorcycles and bicycles, which have one wheel followed by another....
- Uno (dicycle)
- Self-balancing unicycle
- Hubless wheelHubless wheelA hubless wheel is a type of wheel with no center hub. To be precise, however, the hub is actually almost as big as the wheel itself. The axle is hollow, following the wheel at very close tolerances...
External links
- The Museum of Retro Technology - The strange story of vehicles with insufficient wheels
- Channel 4's Scrapheap Challenge page on the Monowheel
- Monovelo, the 2008 Beijing Olympic Games Monowheel
- Wheelsurf, the Dutch/Brazilian motorized Monowheel
- McLean Rocket Roadster Monocycle - U.S. street-legal Buick 215 V8-powered monocycle built by Kerry McLean.
- Ben Wilson's simplified, DIY monowheel
- The RIOT Wheel is a huge, heavy motorized single-wheel vehicle, originally built for Burning Man, the natural home of deviant vehicles
- Monowheels the Weirdest Technology Known to Man
- Speedy New Motor-Hoop Amazes Italians, Popular SciencePopular SciencePopular Science is an American monthly magazine founded in 1872 carrying articles for the general reader on science and technology subjects. Popular Science has won over 58 awards, including the ASME awards for its journalistic excellence in both 2003 and 2004...
, December 1924, page 40, Scanned by Google Books: http://books.google.com/books?id=FSkDAAAAMBAJ&pg=PA40 - Amazing New Motor-Driven Hoop May Be Car of the Future, Popular SciencePopular SciencePopular Science is an American monthly magazine founded in 1872 carrying articles for the general reader on science and technology subjects. Popular Science has won over 58 awards, including the ASME awards for its journalistic excellence in both 2003 and 2004...
, May 1932, front cover and page 63, Scanned by Google Books: http://books.google.com/books?id=1ScDAAAAMBAJ&printsec=frontcover - War Tank on One Wheel, Operated by One Man, Popular SciencePopular SciencePopular Science is an American monthly magazine founded in 1872 carrying articles for the general reader on science and technology subjects. Popular Science has won over 58 awards, including the ASME awards for its journalistic excellence in both 2003 and 2004...
, November 1933, front cover and page 47, Scanned by Google Books: http://books.google.com/books?id=7CcDAAAAMBAJ&printsec=frontcover - Cycle World: Circle Cycle
- Imapct Lab: History of the World’s Craziest Invention - The Monowheel
- Home & Garden Publications: Vehicles with Insufficient Wheels