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==== Past week report ==== ==== Report for the week 6/3 ====
===== SRM Inertial Damping and Residual Motion Stuff =====
 * See Klog [[http://klog.icrr.u-tokyo.ac.jp/osl/?r=9064|9064]]
 * SRM IP L and T is blended at ~110 mHz (partially optimized by gradient descent, stopped after 10 iterations, then manually adjusted.) while IP Y is blended at 260 mHz (Lucia's old filter). The stability test was carried over the past weekend with inertial damping and all other stages on. The system seems stable.
 * To study to performance of the inertial damping, I improvised an OL windshield for SRM.
 * Another round of diagonalization was carried just because we have better sensitivity.
 * With IP LVDT damping and other controls on, the residual motion is as follows [[http://klog.icrr.u-tokyo.ac.jp/osl/?r=9086|9086]]:

RMS Displacement:
|| || Requirement || Result ||
|| L || 0.4 µm || 0.1076 µm ||
|| P || 1 µrad || 0.0569 µrad ||
|| Y || 1 µrad || 0.0598 µrad ||

RMS Velocity:
|| || Requirement || Result ||
|| L || 0.5 µm || 0.1014 µm/s ||
|| P || / || 0.2165 µrad/s ||
|| Y || / || 0.1776 µrad/s ||

 * I measured the residual motion with inertial damping, inertial damping without LVDT DC, normal damping without LVDT DC. Results are pretty similar.
 * I modified the optimization algorithm to allow fine learning. The cost plateaued after ~300 iterations and the blending frequency was at 78.6 mHz. I tried implementing this blending filter but the system went unstable.

===== SR3 Inertial Damping =====
 * The calibration, diagonalization for IP geophones was done.
 * I measured and fit noise floor for LVDTs and geophones.
 * I found that the IP geophones have a much higher noise level than those from SRM. (1 order of magnitude higher, see [[http://klog.icrr.u-tokyo.ac.jp/osl/?r=9088|9088]])
 * This explains why the optimization result of the blending filter converges much quicker than that of SRM, because the geophone noise level limits the blending frequency to be at ~ 130 mHz.
 * However, when the system went unstable when the blending filter was implemented. I should try a higher blending frequency or manually adjusting the blending filter to have a proper shape.
Line 20: Line 49:
 * Help commisioning.
 * Somehow design better cost functions which could help limiting the blending frequency and changing the shape of the blending filter effectively.
 * Inertial damping and OL windshield for BS and (SR3, if haven't done already).
 * Type B Operation Manual.
 * A more pleasant VIS Status Monitor.

Agenda/Minutes of the VIS Meeting on 2019/6/7

2019/6/7 13:30 -

Zoom Meeting

Participants:

Progress report

Schedule

Site work schedule: [[|XLSX]]

Type-A (Takahashi)

Past week report

Plan for coming weeks

Type B (Mark)

Report for the week 6/3

SRM Inertial Damping and Residual Motion Stuff
  • See Klog 9064

  • SRM IP L and T is blended at ~110 mHz (partially optimized by gradient descent, stopped after 10 iterations, then manually adjusted.) while IP Y is blended at 260 mHz (Lucia's old filter). The stability test was carried over the past weekend with inertial damping and all other stages on. The system seems stable.
  • To study to performance of the inertial damping, I improvised an OL windshield for SRM.
  • Another round of diagonalization was carried just because we have better sensitivity.
  • With IP LVDT damping and other controls on, the residual motion is as follows 9086:

RMS Displacement:

Requirement

Result

L

0.4 µm

0.1076 µm

P

1 µrad

0.0569 µrad

Y

1 µrad

0.0598 µrad

RMS Velocity:

Requirement

Result

L

0.5 µm

0.1014 µm/s

P

/

0.2165 µrad/s

Y

/

0.1776 µrad/s

  • I measured the residual motion with inertial damping, inertial damping without LVDT DC, normal damping without LVDT DC. Results are pretty similar.
  • I modified the optimization algorithm to allow fine learning. The cost plateaued after ~300 iterations and the blending frequency was at 78.6 mHz. I tried implementing this blending filter but the system went unstable.

SR3 Inertial Damping
  • The calibration, diagonalization for IP geophones was done.
  • I measured and fit noise floor for LVDTs and geophones.
  • I found that the IP geophones have a much higher noise level than those from SRM. (1 order of magnitude higher, see 9088)

  • This explains why the optimization result of the blending filter converges much quicker than that of SRM, because the geophone noise level limits the blending frequency to be at ~ 130 mHz.
  • However, when the system went unstable when the blending filter was implemented. I should try a higher blending frequency or manually adjusting the blending filter to have a proper shape.

Plan for coming weeks

  • Help commisioning.
  • Somehow design better cost functions which could help limiting the blending frequency and changing the shape of the blending filter effectively.
  • Inertial damping and OL windshield for BS and (SR3, if haven't done already).
  • Type B Operation Manual.
  • A more pleasant VIS Status Monitor.

Type-Bp (Shoda)

Past week report

Plan for coming weeks

OMMT & OSTM

Past week report

Plan for coming weeks

VIS electronics (Tanaka)

Past week report

Plan for coming weeks

Other site works

Safety

  • Incidents:
  • Foreseen risks
    • Type-A:
    • Type-B:

Discussion

  • Engineering run on 6/8

Travel Plans

  • Travel (Week of 6/10):
    • Takahashi:
    • Sato:
    • Mark:
    • Hirata:
    • Shoda:
    • Fujii:
    • Tanioka:
    • Tanaka:
    • Terrence:
  • Travel (Week of 6/17):
    • Takahashi:
    • Sato:
    • Mark:
    • Hirata:
    • Shoda:
    • Fujii:
    • Tanioka:
    • Tanaka:
    • Terrence:

Next meeting

On 2019/6/14(Fri)

KAGRA/Subgroups/VIS/VISMinutes20190607 (last edited 2019-06-07 14:34:06 by YoichiAso)