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Unread 06-05-2010, 08:09
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Re: The spread of pinching rollers this year

Quote:
Originally Posted by Jared341 View Post
Can somebody explain the physics behind the "intake must run at >=2x robot speed" assertion? I've heard this before, and even designed with it in mind, but only now do I stop to think about it.

Intuitively, I don't see why running at >1x robot speed wouldn't work?
I'm guessing it may have come from the fact that the tangential velocity, with respect to the ground, of the top of a wheel, is twice the velocity of the vehicle to which it is connected.

So the reasoning goes: the roller must turn at 2x robot speed in order to keep the ball from escaping when backing up.

But that reasoning is flawed. The tangential velocity of the top of the wheel with respect to the robot is the same as the velocity of the robot.

There may be other reasons for the 2x number.


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