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Unread 16-03-2010, 23:18
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Ether Ether is offline
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Re: fine control of robot with mecanum wheels

Quote:
Originally Posted by StevenB View Post
This may be something you've already tried, but you might want to consider a nonlinear joystick mapping. That is, when you push the joystick halfway, you only move at 1/4 speed instead of 1/2. This gives you finer control of slower movements, while allowing you to still use the full speed range. Very rarely do you care if you move at 3/4 speed vs full speed, but you definitely care about 0 vs 1/4 - thus, you can stretch the axes accordingly.
All you have to do is square the input, making sure to preserve the sign.
Yes, it's already been tried:
http://www.chiefdelphi.com/forums/sh...d.php?p=921992


Quote:
A second note - if this is a first or second year team, my suggestion is, "get used to it."
I'd like to hear from any teams that have implemented closed-loop wheel speed control via encoders connected directly to Jags, on a bot with mecanum wheels.

Also, are any teams using shiftable transmissions (high and low gears) ?



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