Vehicle: Car: Steering
Hemicyclic Steering   (+3)  [vote for, against]
The wheels turn in a semicircular motion.

All cars that I know of cause one of the front wheels to move forward and the other to move backward some amount when the wheels are turned, which causes some minor problems.

I have an idea to change that; Each of the turning wheels would have its own semicircular track which would be horizontal around the wheel. The wheel and suspension would would be attached to the track, and would be able to slide forward and back along the track (on ball bearings?). The steering could be achieved either by a curved rack and a pinion (which would allow the wheels to turn approximately 90 degrees), or it could be done hydraulically (which would allow the wheels to turn almost 180 degrees).

This should also clear up some room in between the wheels.

If the wheels are able to rotate almost sideways, then you would have problems trying to move or accelerate from a stop if the wheels were turned completely. This could be overcome by making the wheels powered, either by electric or hydraulic motors.

This would probably not make it easier to steer if it is not powered steering. This would add some weight and complexity.

A similar idea to this one exists (not on the halfbakery) that has an entire circular track around the wheel, which would make the vehicle wider even when its going straight.
-- BJS, Jun 05 2007

"You'd look sweet upon the seat of a Hemicycle built for two".
-- normzone, Jun 05 2007

So, what you want is zero scrub radius on turning. Well, your idea sounds possible, if a little hard to understand without a picture.
-- 5th Earth, Jun 06 2007

How are you linking the two wheels together to ensure they turn in concert?
-- Galbinus_Caeli, Jun 06 2007

Book them with the same promoter?
-- normzone, Jun 06 2007

I'm not...? If it has rack and pinion, then each pinion could have an axle with a bevel gear on the end, and the two bevel gears would be turned with a third bevel gear. If it is hydraulic, then I will just hope the wheels stay pointing in the same direction, since the fluid would be moved with a single pump. If it is high tech, then it will use position sensors and a CPU to automatically compensate for any difference between the two.
-- BJS, Jun 06 2007

Let me clairfy this proposition. You sugesting that the turning point of the tire be changed, correct?
-- evilpenguin, Jun 07 2007

-- BJS, Jun 07 2007

"This would probably add some weight and complexity."

Yeah, that's an understatement. Better might be to just have wheels mounted on shock spindles, although that would be also difficult to package.
-- RayfordSteele, Jun 07 2007

So, you're changing the turning point of the tire. Where would the effective center point of rotation be? Right in the center of the tread contact patch? Is that the goal?

That sounds to me like it would be harder on the tire.

Where is the wear that your ware seeks to reduce?
-- half, Jun 07 2007

You're probably right, but it sounded pretty good didn't it?
-- BJS, Jun 07 2007

random, halfbakery