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Unread 20-03-2012, 23:02
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Ether Ether is offline
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Re: Something other than PID

Quote:
Originally Posted by IndySam View Post
We use a shooter that is different than most of the robot out there. We call it a fling-a-pult. It is extremely accurate but looses force as battery voltage is reduced causing us to be short sometimes.

Unlike the standard wheeled shooters our two fisher price motors only run for a fraction of a second so PID really doesn't work. What we need is a good way to simply adjust the voltage applied to the shooter motors in accordance with the reduction in battery voltage.

We are using java, any good ideas.
If you are using Jag controllers via CAN, there is a voltage command mode.

You command the desired voltage, and the Jag automatically adjusts the output PWM duty cycle to give you that desired voltage, regardless of the supply voltage. Unless, of course, the supply voltage is less than the commanded voltage.