Reports until 12:09, Friday 29 June 2012
H2 SUS
jeffrey.kissel@LIGO.ORG - posted 12:09, Friday 29 June 2012 - last comment - 17:31, Friday 29 June 2012(3306)
H2SUSITMY Damping Configuration List of Times
I've configured H2 SUS ITMY this morning in various states damping that we've developed over the past few days. I'll post the results later, but for future data mining:

All data taken with BSC8-HPI ON (IPS Loops only), and BSC8-ISI ON (Damping loops only).

    Time                              H2SUSITMY Damping Loop Status                Gains [L,T,V,R,P,Y]
(1) Jun 29 2012 (13:45 - 14:07) UTC   Damps ON, Baseline Filters and Boosts ON     [-20, -5, -2, -0.3, -0.033, -0.1]

(2) Jun 29 2012 (14:10 - 14:33) UTC   Damps ON, Baseline Filters and Boosts ON     [-10, -5, -2, -0.3, -0.033, -0.1]

(3) Jun 29 2012 (14:35 - 14:57) UTC   Damps ON, Baseline Filters only              [-10, -5, -2, -0.3, -0.033, -0.1]

(4) Jun 29 2012 (15:00 - 15:23) UTC   Damps ON, Baseline Filters only              [ -1, -5, -2, -0.3, -0.1, -0.1]

(5) Jun 29 2012 (15:25 - 15:40) UTC   Damps OFF


The hope is that measuring these configurations back-to-back, over the course of a quiet morning (times are ) will give a better representation of their relative amplitude difference.

Also, just an update from B Team think tank:
We took some open loop gains from this morning on ETMY as well. Data to come, but it looks like, after adding the low frequency boost, we're back at LOTS of pitch gain, even with -0.03. The theory now is that because we're squashing pitch so hard, we've effectively locked the TOP mass to the cage, therefore creating a triple pendulum in pitch the directly transmits ISI input motion.

Hence, another quick fix to try would be to reduce the Pitch by another factor of three (leaving all else the same as config (1) above), for a total reduction from original by a factor of 10, from -0.1 to -0.01.


Comments related to this report
keita.kawabe@LIGO.ORG - 17:31, Friday 29 June 2012 (3317)

red: P gain = -0.06

blue: P gain = -0.01

green: P gain = -0.033

But really, you need some on/off/on/off type test.

Images attached to this comment