14-01-2007, 16:42
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Join Date: Jan 2004
Rookie Year: 2003
Location: New York
Posts: 2,000
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Re: Crab drive without a pot
Quote:
Originally Posted by Ian Mackenzie
True, but normal potentiometers have the nasty disadvantage of having a hard stop. When we did swerve drive in 2004, we broke a lot of potentiometers (especially in testing) by turning them too far. In hindsight, it might have been a better idea to use encoders, set the wheel to a known position at the start of the match, and probably have a limit switch as a backup that would be triggered (e.g.) when the wheel was straight ahead - so if anything happened, you could have a reset button that would spin the wheel until it triggered the limit switch and then would reset the encoder count. (You could also do this on the fly - every time that switch happens to be triggered, have an interrupt that corrects the encoder count.)
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Did you try using a 10-turn pot?
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