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Unread 30-08-2010, 02:32
AustinSchuh AustinSchuh is offline
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FRC #0971 (Spartan Robotics) #254 (The Cheesy Poofs)
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Join Date: Feb 2005
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Re: Stepper motors in swerve drive?

Quote:
Originally Posted by jspatz1 View Post
When FRC robots use a gearmotor and feedback pot/encoder to do positioning in FRC, we are doing what some would call a "poor man's servo," but a real one would be superior.
I personally would much rather write my own feedback loops than use the ones embedded in a hobby servo. Hobby servo control loops, unless designed with adaptive controllers (which I highly doubt and aren't in the standard analog servos) have to be tuned for stability over the entire range of loads that you will apply as compared to the exact load that you are going to apply to the motor. For example, if you attach an analog hobby servo to a large block, it won't go to the goal nearly as fast as you could achieve with a custom tuned loop. You can also apply information of the surroundings (254's kicker pullback loop took the battery power into account) to a custom loop, while the servo will have no hope of compensating for that out of the box.