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Unread 05-02-2016, 16:20
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Re: Problems with Encoders

Quote:
Originally Posted by Dan Waxman View Post
By "overcoming inertia" I just mean go from not moving to moving.
That would be static friction and motor controller deadband, not inertia. You can "overcome" friction and deadband, but you never "overcome" inertia: it is always there even when the motor is turning.

Quote:
Overcoming inertia was probably not the best terminology, but I couldn't think of a better term.
If you take a physics class, you'll learn all about inertia and Newton's Second Law

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So I'll explain what I mean by effective range by example. With the CIM I was testing this with originally, I found the motor started moving at around .14. This means that everything from -.13 to .13 wouldn't move the motor at all.
Yes. That's static friction and motor controller deadband.

Quote:
So what my function did is just make every value -1.0 to 1.0 move the motor.
Very good. You're re-mapping the joystick output. There are occasions (as you have discovered) when this can be quite useful. You're encountering the fun of learning useful new stuff.

Just for the record, you don't have to write your own PID to use joystick re-mapping. Just send the re-mapped joystick values to the PID, instead of the raw joystick values.


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