The wheel was invented more than 5000 years ago, but improvements are still being invented.

Pat.nr.us005374879 / Killough platform

This wheel is constructed to drive in any direction.

spherical wheels A wheel unit has two spherical freewheeling wheels. They sit in a frame which can be turned by a motor. The frame is made so one of the two wheels always touches the ground. In this way traction in one direction is achieved, and freewheeling in the orthogonal direction. By combining a number of these wheel units, traction in any direction can be achieved.

The wheel units can be placed on the bottom of the vehicle in a quite freely chosen number and pattern. The pattern works if the vehicle cannot be pushed or turned, with the motors braked.

To steer you have to see to that the motors has correct speed and rotational direction. The vehicle can drive in any direction, turn in place, and even do a combination of those for that matter...

A vehicle with three wheel units is a popular project among Lego enthusiasts.

Pat.nr.us003876255 / Ilon / Mecanum

This wheel is constructed to drive in any direction.

The wheel has a number of freewheeling rollers around the edge. The rollers are oblique at 45 degrees. When the wheel rotates it will generate traction in the rollers longitudinal direction. By combining more of these wheels it is possible to get traction in any direction. The rollers are formed to make the wheel profile a circle, to lessen vibrations during driving.

So this wheel can do the same as the preceding one, but it is a better fit for traditional vehicles.

Every wheel must have its own motor. The vehicle is steered by varying speed and rotational direction of the wheels. There is no need to turn the wheels to go through a curve, so the vehicle doesn't need any steering gear.

The wheel was conceived by the swede Bengt Ilon in 1973. He worked as an engineer in the Mecanum AB company.

From a swedish test in 1976.

Demonstrator from the Omnix Technology company.

Golf Cars International

This wheel is constructed to spare golf courts.

Golf Cars International The wheel comprises slats fitted on a normal rubber tire. The slats are about 20 centimeter long, and are fixed with joints of elastic band. When the wheel turns, the slats on the ground will stay in place, because it is easier for the joint to turn than for the slat to move. There will always be 3 slats on the ground, and so they spreads the load over 154 square centimeters (the slat width is exaggerated in the drawing).

Golf cars with these wheels avoid making marks when they turn, and they spreads their load over a large area. For comparison a conventional golf car wheel has a contact area of only about 40 square centimeters.

S. Dixon

This wheel is constructed to give motorcycles a better grip in curves.

The rim is covered with 24 units, comprising a plate placed on an axle, and two shock absorbing studs that restricts the plate swing. The plates are curved and has a rubber layer mounted. When the wheel leans the plates will tilt, so the whole surface stays in contact with the ground.

A prototype has been made, which has been tested at up to 130 km/t. It feels like a conventional wheel when driving in a straight line. In curves the most remarkable is that so little effort has to be put in. The grip in curves has improved 40%, and power transmission to the road has improved 26%. Furthermore it turns out that the wheel has good abilities in wet conditions, its water displacement is 50% better than a conventional tire.

Pat.nr.us0d0336710

This wheel is constructed to drive up and down stairs.

Three conventional freewheeling wheels is placed on a three armed holder, which is itself freewheeling. When a step is crossed the three armed holder will make a 1/3 rotation.

Caddy for transporting harps. The K-2 model from the Harp Caddy company.