Botanical Glossary - Home

Two local children pause to contemplate the effects of this shinny ride set up in Maria del Tule, Oaxaca Mexico. This unusual looking Tilt-A-Whirl is a Japanese facsimile of a ride that was originally designed, invented and manufactured by the Sellner Manufacturing Company. The show that is set up here in Tule is a very small traveling carnival that sets up in shopping malls and cordoned off streets in Southern Mexico.

Tilt-A-Whirl is one of the best-known flat rides, designed for commercial use at amusement parks, fairs and carnivals in which it is commonly found. The rides are manufactured by Sellner Manufacturing of Faribault, Minnesota.
The Tilt-A-Whirl is a platform-type ride, consisting of seven freely-spinning cars that hold four riders each, which are attached at fixed pivot points on a rotating platform. As the platform revolves, parts of the platform are raised and lowered, and the resulting centrifugal and gravitational forces on the cars cause them to spin in different directions and at variable speeds. The weight of passengers in these cars may intensify or dampen the spinning motion of the cars, adding to the unpredictable nature of the motion. Mathematicians call this unpredictable nature chaotic motion. Sellner requires all riders to be 46 inches (120 cm) or taller unless they ride with an adult; however, no infants are allowed.
Physicists Bret M. Huggard and Richard L. Kautz came up with a mathematical equation that approximates the motion of the Tilt-A-Whirl. Although it was without knowledge of chaos theory that Herbert Sellner invented the ride, in his patent text he clearly demonstrates an appreciation of chaos -- "A further object is to provide amusement apparatus wherein the riders will be moved in general through an orbit and will unexpectedly swing, snap from side to side or rotate without in any way being able to figure what movement may next take place in the car."