Global longitudinal quad damping vs. local damping

Document #:

LIGO-G1200774-v8

Document type:

G - Presentations (eg Graphics)

Abstract:

Shows how we can decouple damping noise from cavity signals by damping suspension along global ifo coordinates rather than local coordinates.
The cavity control itself can be used to apply damping along the differential cavity DOF. The common mode dynamics, invisible to the cavity, can be damped by applying the same signals to each suspension. This decoupling depends on the pendulums being nearly identical.

Files in Document:

• G1200774-v8 (Cavity_Control_Influence_on_Damping-G1200774-v8.pdf, 4.9 MB)

Other Files:

• G1200774-v8 (Cavity_Control_Influence_on_Damping-G1200774-v8.pptx, 6.1 MB)

Topics:

• Basic R&D

Authors:

• Brett Shapiro

Keywords:

damping hierarchical control suspension ISC

Notes and Changes:

Includes simulations of noise performance using realistically different quadruple suspensions.

Related Documents:

• LIGO-G1200632: Towards Applied Heirarchical Control