A square wheel is a wheel that, instead of being circular, has the shape of a square. While literal square wheels exist, a more common use is as a metaphor meaning stereotypically bad or naïve engineering (see reinventing the wheel).
A different type of square-wheeled vehicle was invented in 2006 by Jason Winckler of Global Composites, Inc. in the United States. This has square wheels, linked together and offset by 22.5°, rolling on a flat surface. The prototype appears ungainly, but the inventor proposes that the system may be useful in microscopic-sized machines (MEMS).
In 1997 Macalester College mathematics professor Stan Wagon constructed the first prototype of a catenary tricycle. An improved model made out of modern materials was built when the original vehicle wore out in April, 2004.
In 2012, MythBusters experimented with modifying vehicles with square tires, determining that, with speed, a truck fitted with square wheels can deliver a relatively smooth ride.
- Peterson, Ivars (4 April 2004), "Riding on Square Wheels", Science News 165 (14), retrieved 2009-05-03
- A Catenary Road and Square Wheels, New Trier High School, Winnetka, Illinois, archived from the original on September 20, 2006, retrieved 2009-05-03
- Non-Circular Wheels, Physics and Astronomy Lecture Demonstrations, University of Iowa, retrieved 2009-05-03
- Square Wheel Car Propels Itself by Shifting Weight - Possible MEMS Locomotion, Global Composites, 2 December 2005, retrieved 2009-05-03
- Wagon, Stan. "Untitled". Retrieved 19 May 2010.