A Eunicycle is a computer controlled, partially self-balancing, motorized 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...

 invented by Trevor Blackwell

Trevor Blackwell

Trevor Blackwell is a computer programmer, engineer and entrepreneur based in Silicon Valley.Blackwell is a developer of humanoid robots. He is also the inventor of the Eunicycle, essentially a one-wheeled Segway. Dr. Blackwell is the founder and CEO of Anybots and a partner at Y Combinator.- Life...

. It uses a computer control system similar to the one used by the Segway HT that servos its wheel to balance itself by keeping the contact point of the wheel below the center of mass

Center of mass

In physics, the center of mass or barycenter of a system is the average location of all of its mass. In the case of a rigid body, the position of the center of mass is fixed in relation to the body...

 of the vehicle in the front-to-back direction. To balance from side to side, the rider must rotate the vehicle the same way a unicyclist does, enabling the balancing servo to balance in the new direction.

The Eunicycle is based on an open design

Open design

Open design is the development of physical products, machines and systems through use of publicly shared design information. The process is generally facilitated by the Internet and often performed without monetary compensation...

; the engineering drawings and control software source code

Source code

In computer science, source code is text written using the format and syntax of the programming language that it is being written in. Such a language is specially designed to facilitate the work of computer programmers, who specify the actions to be performed by a computer mostly by writing source...

 are available from the website.

See also

• Bicycle and motorcycle dynamics
  Bicycle and motorcycle dynamics
  Bicycle and motorcycle dynamics is the science of the motion of bicycles and motorcycles and their components, due to the forces acting on them. Dynamics is a branch of classical mechanics, which in turn is a branch of physics. Bike motions of interest include balancing, steering, braking,...
  
  
• Self-balancing unicycle
• 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...
  
  
• Uno (motorcycle)