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Unread 27-09-2016, 22:29
Oblarg Oblarg is offline
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AKA: Eli Barnett
FRC #0449 (The Blair Robot Project)
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Re: Tuning PID Constants Over a Range

Quote:
Originally Posted by Paul Copioli View Post
Eli,

While your statement is true, we have found that simply putting a motion profile on your input will eliminate the need for cascading control.

To me, the motion profile (whichever you choose .. we use trapezoidal acceleration) is a more pure way to do it. We all know that if you give a step input to a motor it really doesn't behave that way so why not give it an input it really can perform.

We have found that motion profile + feedforward gain + PID work for all of our telemetry navigation needs, whether it be for driving or moving a ridiculously complicated arm.

Austin and his crew use state space, but I am too simplistic for all that awesomeness so I stick with profile + FF + PID.

Paul
We're working on motion profiling this preseason - I entirely agree that it's a conceptually better way to do it.
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Member, FRC Team 449: 2007-2010
Drive Mechanics Lead, FRC Team 449: 2009-2010
Alumnus/Technical Mentor, FRC Team 449: 2010-Present
Lead Technical Mentor, FRC Team 4464: 2012-2015
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