One-Wheeled Wonder

Barring the odd three-wheeler, most wheeled vehicles throughout history have sported an even number of wheels, usually four. But that doesn't seem streamlined enough for certain aesthetics. This trope describes creatures (usually robots or cyborgs) or vehicles that move by balancing on a single wheel.

Try not to think too hard about how it stays upright.

Truth in Television insofar as the unicycle has been in use since at least the late 19th century, when riders of penny-farthings found that they could lean forward, raising the much smaller rear wheel off the ground, and still maintain balance. Eventually the rear wheel was left off of the design altogether, resulting in the modern unicycle. However, it has largely been regarded as a gimmick since the development of the safety bicycle (what most people think of simply as a "bicycle").

Monowheel Mayhem is a subtrope in which a vehicle is a single wheel. Non-robotic creatures to which this trope applies are examples of Bizarre Alien Locomotion.


Examples:

    open/close all folders 

    Films — Animation 

    Films — Live-Action 
  • The droid waitress WA-7 in Dexter's Diner on Coruscant from Attack of the Clones serves customers while balanced upon a single wheel.
  • Officer Shrift from the animated adaption of The Phantom Tollbooth gets around on a wheel that resembles that of a rolling chair, connected to something that looks like a car jack that can be raised to compensate for his height. It's unclear whether this is a vehicle that he is seated on under his long jacket or a part of him or what.
  • One of the bikes in the Mega Race during Spy Kids 3: Game Over is a motorized unicycle with a very high seat.

    Literature 
  • Ciaphas Cain: One of the techpriests in Emperor's Finest and Caves of Ice had his lower body replaced with a single wheel. Made even worse by the fact that techpriests have huge metal dendrites attached to their backs and like to replace as much of their body with metal as possible, though Ciaphas mentions that he must have very good gyroscopes to work.
  • The Mulefa in the third book of Phil Pullman's His Dark Materials trilogy. They're a race of Starfish Aliens who use a giant round seed as a wheel, and attach it to their two middle feet.

    Live-Action TV 

    Video Games 
  • Claptrap from the Borderlands series is a roughly half-human-height robot that gets around this way.
  • Some of Dr. Robotnik's robots from the Sonic the Hedgehog video game series are like this. The earliest (and probably most notable) example is Motobug from Sonic The Hedgehog 1.
  • The Securitron robots, which form the personal guard of the post-apocalyptic mogul Mr. House from Fallout: New Vegas, look like this.
  • Robot Medics in Team Fortress 2 are the only robots in the game to not use legs, instead opting for a single wheel.
  • Mega Man
  • The helper Wheelie from Kirby Super Star.
  • Skylanders has two: The legendary Giant Bouncer and the Swap Force entrant Magna Charge.
  • Maestro in Mystery Mountain. He is the only android designed this way; Mrs. Beasley and Eggbert hover and the rest are bipedal.
  • Roadkill Rodney, a robotic enemy from the arcade game Teenage Mutant Ninja Turtles and its ports. Not only could it stay upright on one wheel, but it could send out an electric cable to try to zap a turtle. Whether or not it succeeded, it never fell over until it was defeated.
  • The obscure video game MoHo had gladiatorial robots with a single ball on which they moved.
  • The Stillborn Franchise Defenders of Dynatron City included Buzzsaw Girl, a mutant heroine whose lower body was a buzzsaw that functioned as a wheel.
  • In the Super Famicom Product As Superhero game UFO Kamen Yakisoban: Kettler no Kuroi Inbou, riding the Yakisoban Unicycle (a non-action toy in the commercials) provides Temporary Invincibility.
  • Star Wars: Droidworks has several locomotion options for wheeled droids, including one that's a non-magnetic unicycle, which is useful for avoiding being caught by electromagnets, and another as a streamlined tricycle.

    Western Animation 

    Real Life 
  • The unicycle, of course.
  • A self-propelled unicycle has been developed. Like a Segway, all the rider need do is lean forward. The unicycle more or less self-balances.
  • The Uno-Wheel Motorcycle, the first fully functional one wheeled-motorcycle. Though technically it has two wheels side-by-side, it looks quite close to Code Lyoko's Overbike.