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Unread 29-03-2010, 10:07
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Ether Ether is offline
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Re: How Do mecanum wheels handle the bumps?

Quote:
Originally Posted by sgreco View Post
Mechanum wheels seem nice in theory, but if I'm not mistaken, a team has never won nationals with a mechanum drive. If they meet tough defense they can easily be out pushed. They're good for qual matches with low defense, but I'll be interested to see how they fair in elims in Atlanta.
Please understand: I am not claiming that mecanum wheels are the superior design choice for Breakaway.


Quote:
Originally Posted by sgreco View Post
I can't answer for Chris, nor have I done the math, But if you think about a mechanum wheel, its rollers are angled at 45 degree angles in relation to the direction of the wheel. So when you input a speed to go forward, you lose efficiency in that you are transmitting power in a direction that you arent heading in.
I question your claim that "power is being transmitted" in a non-forward direction when the bot is going straight forward.

But that's beside the point.

The question on the table is whether or not "only 71% of the output torque is transmitted in the direction of travel" when the bot is going straight forward (or backward).


Quote:
Think about a free body diagram for physics. You may have 9 N of force in one direction and 2 N in the opposite direction, so you are letting off 11 N of force, but you only have a net of 7 N in the forward direction.
This analogy doesn't appear to apply to the situation at hand.


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