Thread: CAN for dummies
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Unread 21-07-2011, 12:24
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Re: CAN for dummies

Quote:
Originally Posted by daniel_dsouza View Post
Ok, cool. So I gather that I use rpm for speed, but what do I values should I use for position?
A PID controller takes a "setpoint" input and a "processVariable" input.

The setpoint is the value you want for whatever it is you are trying to control (your computed command).

The processVariable is the present measured actual value of what you are trying to control (the feedback from the sensor).

You have to scale the setpoint or the processVariable so that they are in the same units.

So if your command is in "feet", you have to scale your processVariable to be in feet. You do that by either calculating how many encoder pulses correspond to 1 foot of motion, or you can measure it experimentally.



Last edited by Ether : 21-07-2011 at 12:31.
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