The wheel is one of the oldest inventions, which laid the foundation for further development of human civilization. People realized thousands of years before our era that it was easier to wheel something than to carry on the back.
Some theories suggest that first wheels were used for domestic purposes rather than for transportation: millstones and potter's wheels may have been prototypes for inventing a more comfortable way of carrying heavy objects and transporting people. The earliest finding that points to the wheel’s creation dates to the last quarter of the 5th millennium BC. In an archaeological dig near the Romanian city of Iași, researchers found clay models of wheels of toy carriages.
The wheel began its evolution from common wooden logs – rollers that were put under heavy loads. Over the centuries, the construction was improved: it was lightened and strengthened by adding spokes and metal rims, and began to be made entirely of iron. Nowadays wheels are complex electronic and mechanical devices.
Without unnecessary maneuvers
The problems of the earliest wheels, which had difficulty handling turns, are long in the past. And the new prototypes make parallel parking on city streets easier – you can actually drive into the “pocket” between two cars sideways.
One of the technologies is called the omnidirectional wheel. It allows a car to move sideways and turn around without unnecessary maneuvers, practically on the spot. The design is based on rollers or discs in a circle, which can rotate perpendicular to the direction of rotation of the wheel. A video demonstration of the invention mounted on a car appeared on the Internet five years ago. However, the idea of an omnidirectional wheel was patented in 1919. Such wheels are mostly used in the production of robots.
A technology similar to the omnidirectional wheel is the “Swedish wheel,” or, as it is more commonly known, the “Ilon wheel” named after its inventor, Bengt Ilon. The wheel also has rollers around its circumference, just like the omnidirectional wheel, but they are arranged at a 45-degree angle to the wheel's axis. The car on Ilon wheels is able to slide left and right, move at an angle without turning the body of the vehicle or turn on the spot. Vehicles with such wheels move sideways with minimal friction force and, unlike tracked vehicles, which can also turn on the spot, do not damage the pavement. This technology is in demand, particularly in the production of warehouse loaders that require maximum maneuverability.
How to get rid of spokes in favor of aesthetics, smooth running and better braking, but at the expense of high price and excessive “tenderness” of the design, which is sensitive to deformations? The story of orbital wheels without spokes and hubs began in the early twentieth century, when a promising mode of transport was the monocycle – a single wheel, in which the outer disc rotates, and the fixed inner disc is designed to install the engine and driver's seat. In fact, it is a large bearing, as is the orbital or osmos wheel.
A tire and a brake disk are attached to the outer wheel disc, while the inner one is connected to the suspension. More popular are motorcycles with orbital wheels, although there are also car designs with orbital wheels. The design allows making vehicles with variable fork trail: larger for stability at high speeds and shorter for maneuverability at low speed.
Despite the futuristic and attractive design, as well as certain technological advantages, such wheel designs didn’t gain popularity. The complexity of the design significantly increases the price of transport and wheel parts positioned close to the ground become dirty quickly.
To ride softer
Some technologies suggest incorporating shock-absorbing elements into the wheel design. For example, in loopwheels, the spokes have been replaced with loops made of resilient material. The ends of the band are attached to the hub and the loop rests on the wheel rim in the middle. The center of the wheel actually “floats” on these loops inside the rim, softening potholes and curbs on the road. Such wheels are used for wheelchairs, yet there are also bicycle models.
For car drivers who often get into various off-road situations, the concept of a wheel that can be transformed depending on the track’s condition has been developed. The spokes of the roadless wheel fold and extend: the wheel becomes thinner and higher on asphalt and rock, and folds to increase the grip with the surface on sticky terrain.
Variety of prototypes
Companies around the world continue to reinvent the wheel, experimenting and avoiding proven options. And most inventions are left at the stage of projects or concepts, never pushing tried-and-true variants out of the market.
Airless tire technology offers to get rid of the danger of self-tapping screws on the road: wheels that are made almost entirely of rubber – a single piece without a tire or tube. Manufacturers claim they will last longer, reduce fuel consumption and produce less noise.
Other developments propose to abandon the seasonal change of rubber. It is expected that there will be tires that can extend the spikes out of the rubber by pressing a button.
Wheels are becoming complex systems, which can monitor road conditions and change, when necessary, transmit information to the driver, and even generate electricity to maintain the vehicle's systems. An ancient invention that now resembles only the shape of its first design.
Photo on the homepage velojournal.net
Based on open sources