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Unread 20-05-2010, 15:41
LLogan LLogan is offline
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Re: pic: A mechanum wheel that shouldn't bump around at all.

Quote:
Originally Posted by EricH View Post
Actually, there is a significant observable slowdown when side-to-side is run as compared to front and back. Part of this is due to friction and other inefficiencies (remember, two of the 4 wheels are running backwards); part of it is due to the vectors. I'm not exactly quite sure how that happens off the top of my head; I think Alan Anderson posted an explanation a while back.
Yes, I agree with you that there is a significant difference in the two motions. However, the bolded portion of your text is not entirely relevant to the inefficiencies of a mecanum system. Simple vector analysis shows that the strafing motion is theoretically equal to the forwards and backwards motions. The fact that two wheels are running backwards doesn't matter at all (unless you're talking about motor bias, but I don't think you are.). The forward/backwards vectors all theoretically cancel out and leave only the perpendicular vectors, which are, in magnitude, equal to the forward/backward vectors.
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