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Unread 05-01-2009, 02:26
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Re: 4WD Turning Difficulties

Quote:
Originally Posted by Hachiban VIII View Post
What about wheels like this?

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When you want to turn, spin the front and back wheels (wheels on short sides). When you want to drive forward spin side wheels.

Another thing we've considered is "toe."

If the wheels are angled slightly at each corner, spinning all of them in the same direction will allow you to spin in place.

It will also take advantage of the superior transverse friction when driving forward. And will provide some braking to prevent the robot from coasting when making a hard stop.
The wheel's tranverse friction is more than twice the inline (apparently).

Even though their friction sideways is probably less than the omniwheels we're used to on carpet, that doesn't mean they will slide sideways easily in this case.

It doesn't matter that the transverse friction is really low, it matters that relative to that, the inline friction is substantially lower.