Features in the Quad State Space Model

Document #:

LIGO-G1401132-v7

Document type:

G - Presentations (eg Graphics)

Abstract:

A brief summary of the features of the quad state space model available in the generate function:
/ligo/svncommon/SusSVN/sus/trunk/QUAD/Common/MatlabTools/QuadModel_Production/generate_QUAD_Model_Production.m

Notes on how to edit these features yourself are also included.

The features include:

1. Relative SUS/cage sensors and actuators - new in this revision
2. Suspension point reaction forces to connect to the ISI - new in this revision
3. Two-chain models
4. Violin modes: all stages
5. damping: top mass and oplev

Also new behind the scenes, Simulink files now define the layout of the connections between the various pieces of the model and the signal flow. These replace the append/connect lines in generate_QUAD_Model_Productio.m.

More detailed instruction on using the model are commented into the header of generate_QUAD_Model_Production.m.

Files in Document:

• G1401132-v7 (QuadModelFeatures_G1401132-v7.pdf, file is not accessible)

Other Files:

• G1401132-v7 (QuadModelFeatures_G1401132-v7.pptx, file is not accessible)

Topics:

• Modelling

Authors:

• Brett Shapiro

Notes and Changes:

-v7: Added more notes on the violin mode and damping features.

-v6: Added oplev damping and violin modes at all 4 stages.

-v5: A complete rewrite, to reflect a big update in svn rev 7920.

-v4: Added a thermal noise estimate from the silica fibers

-v3: Modified the inputs and outputs for the dual-chain model. Also made all new features compatible with damping loops.

Related Documents:

• LIGO-T1400587: Augmenting the quad MATLAB model with fiber violin modes