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Unread 05-02-2015, 23:57
cstelter cstelter is offline
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Re: How to Program Mecanum

Quote:
Originally Posted by Ether View Post
I don't care for that nomenclature either; I was using it because that's the way the questioner (3786KRRobotics) worded it.

I hope the following is clearer for you:

=

vehicle strafe right:

- front wheels turning CCW (when viewed from their respective sides)

- back wheels turning CW (when viewed from their respective sides)

sides
Yes, this is perfectly clear to me now. It is consistent with what you said earlier and opposite of what the OP had indicated that you corrected. I even found a patent http://www.google.com/patents/US20130292918 also confirming the same. I have no doubt this is true.

But I still couldn't see it. I was about to post again pleading for help in my logic, but then I finally saw it. I kept thinking of the rollers-- not as rolling along their axes, but rather static.

So I had been imagining the front left wheel as it spun in reverse to strafe left. Because I was neglecting the rolling action of the rollers, I imagined that if they were digging into sand, the sand would pile up in front and to the left, pushing the wheel to the right. But finally the light went on an as I finally realized that the roller rolls in a diagonal. So on hard ground, it will push the wheel in the direction that the roller is rolling-- that is forward and left.

So, if all the rollers were stuck, would it then do the opposite as I had originally been imagining? Obviously a lot of burned rubber, but I think it might.

Of course then they probably wouldn't call them rollers!

It's a good day-- I learned something new!
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