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Unread 09-01-2008, 12:11
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Madison Madison is offline
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Re: pic: Omni Design Trial

Quote:
Originally Posted by GUI View Post
Some of the motors force is used by the wheel trying to move sideways, but the rollers aren't actually turning, so all of the wheel's velocity is transferred to the ground.
The difference between mecanum and omni-wheel based holonomic is that on an omni system the wheels actually do move sideways when driving forward, while on a mecanum setup they don't.
The difference you're observing may simply be a function of how much you've tightened the screws on the AndyMark mecanum wheels. We have had a functioning mecanum drive train for more than a year and I swear on my mother that the rollers turn while we're driving forward or backward or sideways or upways or downways or anyways at all.

You cannot transfer velocity to the ground. You can impart a force on the ground and the reaction to that force will make your robot move, but the Earth is a bit heavier than your robot and you're probably not having a significant effect at making it go faster or slower.

If the rollers are not turning, as you suggest, then the wheel is not trying to move sideways. If the wheel is not trying to move sideways (as it cannot possibly discern your intention or what the rest of the wheels are doing) it will not, under any circumstances, strafe. A roller that's not turning cannot magically impart a force sideways.
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