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Message ID: 5499     Entry time: Wed Sep 21 14:44:25 2011
Author: Paul 
Type: Update 
Category: SUS 
Subject: ITMY and SRM open loop transfer functions 

 

 Here are the open loop transfer functions for ITMY and SRM. The various settings for the OLTFs were as follows:

Oplev filter used for all OLTFs: 300^2:0

Gains for oplev servos (for each OLTF only the 1 servo for the measured TF was on. They are all set back to 0 now):

SRM yaw gain = 1

SRM pitch gain = -1

ITMY yaw gain = -1

ITMY pitch gain = 1

measurement band = 0.2Hz to 200Hz

points = 33

swept sine magnitude envelope: amp = 2 for f > 60Hz, amp = 0.1 for f < 60Hz

Measurement points were from e.g. C1-SUS-ITMY-OLPIT-IN2 to C1-SUS-ITMY-OLPIT-IN1 to give a TF of -(loop gain).

Next step is to divide this through by the sensor reponse (i.e. the calibration factor measured earlier) and the filter response to get just the actuator response. 

 

Attachment 1: ITMY_SRM_oplev_OLTFs.png  18 kB  | Hide | Hide all
ITMY_SRM_oplev_OLTFs.png
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