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Unread 02-05-2007, 18:42
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Re: mecanum vs. omni

Quote:
Originally Posted by 4throck View Post
The one real problem with these drives that we discovered was victor bias. The values that come out are not symmetric, linear, or normal by any means. We ended up using look up tables, ask Kelly for more information about how we did it.
The "center" of the Victor 884 range is NOT 127. It is more like 132 or 133. Some example ranges are provided in this thread in the IFI Forum. I suggest testing your own speed controllers by giving them steady known values (from a pot or wheel and reading it on the dashboard) and looking at the lights.

This makes reversing the motor direction in software difficult, so I suggest just simply reversing the polarity at the Victor output. The motors will still have different power output in forward vs. reverse (that is inherent to the motor) but at least the input electric power will not be the problem. Wheel encoder and yaw rate sensor feedback can correct the former problem.

Here is another good programming link for Jester Drive
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Last edited by The Lucas : 02-05-2007 at 19:18.