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Unread 16-01-2011, 21:31
BigJ BigJ is offline
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Re: Mecanum Advice Request

Quote:
Originally Posted by Jogo View Post
Can you further explain this? Why would you only get 71% when going forward?
Not sure how much you know overall about Mecanum so I'll lay it all out.

Mecanum wheels produce a force at a 45% angle when driven. The x and y components respectively equate to roughly 71~% of the total vector. (Actually thinking about it my sqrt(2) comment makes no sense. it's actually 1/sqrt(2) for each side. 1/1.414 ~= .71)

In my head, without looking at our algorithm it isn't making a ton of sense (since the forward vectors would be 71% too), but I know that when we're running "normally", which is translating at the same speed in every direction, our motors run at only that 71% when going forwards.

EDIT2: It is because the motor outputs in our algorithm are limited by a trigonometric function and motor offsets. It just so happens that our motor outputs when going forwards or backwards are +/- sqrt(2)/2, which is the same ~71%.

We give the drivers the option to drive our motors at 100% forward/backward.

Last edited by BigJ : 16-01-2011 at 21:51.
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