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Message ID: 42     Entry time: Mon Jul 1 13:01:58 2013
Author: Arnaldo Rodriguez 
Type: Optics 
Category: General 
Subject: Brief Parameter Study on P-active Control Loop 

 The following is a plot of the defocus as a function of time with only the proportional gain being nonzero. Only three cases were run before the program crashed.

K_p.png

The dotted line indicates the setpoint.

One can clearly see the loop becomes unstable and oscillates out of control at a proportional gain of 240, and can see the characteristic steady-state offset of the P-controller from the set point develop in the other cases.

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