QUAD DESIGN MEETING

ADVANCED LIGO SUSPENSIONS MIT PROTOTYPE QUADRUPLE PENDULUM SUSPENSION (ETM) REAL VNC: - installed and tested! ( 18.120.0.145 ) http://www.realvnc.com/ INTERNET CAMERA: thread.mit.edu PHOTOS: Mark Barton Calum's SUS page STATUS Quad successfully assembled, aligned, suspended and installed in BSC chamber on solid stack. Chains then aligned to each other and to the table cloth with auto-collimator. 12 local control osems installed and aligned. All of the global control osems at UI and Pen stage aligned and tested. DOCUMENTS 1) SUSPENSION CONTROLS PROTOTYPE TEST PLAN 2) ASSEMBLY DOCUMENT, LIGO-T060039 (does not include any pre-assembly) -ACTION: Need to add effort to align chains and work done with auto collimator! ACTIONS MAIN ITEMS TESTS a) Damping tests with local control -ACTION: - (Brett) z mode and roll node slightly un-stable! x mode (main chain) on the ilog (gain up too high? servo on d-space? open loop xfer func) http://www.ligo.mit.edu/ilog b) Suspension and structural frequency measurements -ACTION: - (Brett) Structure resonance's tests with Brett and Calum have been completed. - DONE!! c) transfer function tests with local control -ACTION: - (Brett) Brett has driven each osem and measured the response. This needs to be repeated in degree of freedom to allow a stable control filter to be created OTHER DOG CLAMPS a) 8 (out of 16) Dogs need to be modified to fit with Ken's temp table. -ACTION: (Brett) 4mm removed from end closest to table (8 DOGS)! - DONE!! OSEMS & ALIGNMENT Checked it is possible to align all of the osems, local and global and have arranged all of the osems in the order they are referenced by the LIGO electronics. - DONE!!! Gain differences between LIGO I and GEO electronics have been corrected and are now understood. - DONE!! -ACTION: All of the osems will need re-aligned once the quad is inside the chamber. The local control damping filter has still to be finalized. I know Jay would like to discuss this further. -ACTION: sat amp need to be changed (discuss with Jay) -ACTION: upper left osem on L2 cable issue? (investigate) -ACTION: Is there an OSEM with its backward polarity? Repeat test to check polarity. Positive offset turn it on and make sure all osems move the same way SUSPENSION a) UI and Top stage, screws need to be trimmed! -ACTION: Calum - DONE!! Parts & hardware being cleaned and baked!! Installed. - DONE!! OSEMS BRACKETS Why no slot in LIGO-D040357 (MPL), when there is a slot in drawing? Think revision issue! Need to clean and ship correct revision. ACTION: Calum - DONE!! Part being cleaned and baked! Not needed. left as spares! - DONE!! spare OSEMS and magnet assemblies were checked and repaired where necessary DONE!! UI MASS MAGNET HOLDERS reference attached pictures Could not see problem? - DONE! -ACTION: Before re-suspending the quad work needs to be done on HEPI -ACTION: The suspension eddy current dampers will be installed by Janeen next week -ACTION: One global control magnet assembly has to be added. -ACTION: If the quad is still locked down it will have to be re-suspended, reference notes from Calum. ELECTRONICS & LED's (out of date refer to work by Ben Abbott) Status. 12 LC at Top mass, 4 GC at Pen mass (Now 3!) and 4 at UI mass, could be cabling issue, see below? -ACTION: Ben to act as investigator & to contact Honeywell! (Stuart offering help!) a) Noise on global control at pen stage? b) wiring to UI mass osems? (At first we thought it was LED but after replacing with 2 osems thoughts moved to something else?) ALL LED's AT UI MASS NOW WORKING! c) Washer a useful addition behind magnet on pen mass to make alignment easier! d) Should we install a bleed wire? e) LED drive (GEO electronics) being replaced? f) side osem main chain - cut wire? - OSEM REPLACED!! Repair of electronics being carried out by Jay! ACTION: (Brett / Rich) Use ESD transfer functions to investigate shielding questions?

STATUS

Quad successfully assembled, aligned, suspended and installed in BSC chamber on solid stack. Chains then aligned to each other and to the table cloth with auto-collimator. 12 local control osems installed and aligned. All of the global control osems at UI and Pen stage aligned and tested.

DOCUMENTS

1) SUSPENSION CONTROLS PROTOTYPE TEST PLAN
2) ASSEMBLY DOCUMENT, LIGO-T060039 (does not include any pre-assembly)
-ACTION: Need to add effort to align chains and work done with auto collimator!

ACTIONS
MAIN ITEMS

TESTS

a) Damping tests with local control -ACTION: - (Brett)
           z mode and roll node slightly un-stable!
           x mode (main chain) on the ilog (gain up too high? servo on d-space? open loop xfer func)
                http://www.ligo.mit.edu/ilog
b) Suspension and structural frequency measurements -ACTION: - (Brett)
Structure resonance's tests with Brett and Calum have been completed. - DONE!!

c) transfer function tests with local control -ACTION: - (Brett)
Brett has driven each osem and measured the response. This needs to be repeated in degree of freedom to allow a stable control filter to be created

OTHER

DOG CLAMPS

a) 8 (out of 16) Dogs need to be modified to fit with Ken's temp table.

-ACTION: (Brett) 4mm removed from end closest to table (8 DOGS)! - DONE!!

OSEMS & ALIGNMENT

Checked it is possible to align all of the osems, local and global and have arranged all of the osems in the order they are referenced by the LIGO electronics. - DONE!!!

Gain differences between LIGO I and GEO electronics have been corrected and are now understood. - DONE!!

-ACTION: All of the osems will need re-aligned once the quad is inside the chamber.
The local control damping filter has still to be finalized. I know Jay would like to discuss this further.
-ACTION: sat amp need to be changed (discuss with Jay)
-ACTION: upper left osem on L2 cable issue? (investigate)
-ACTION: Is there an OSEM with its backward polarity? Repeat test to check polarity. Positive offset turn it on and make sure all osems move the same way

SUSPENSION

a) UI and Top stage, screws need to be trimmed! -ACTION: Calum - DONE!! Parts & hardware being cleaned and baked!! Installed. - DONE!!
OSEMS BRACKETS Why no slot in LIGO-D040357 (MPL), when there is a slot in drawing? Think revision issue! Need to clean and ship correct revision. ACTION: Calum - DONE!! Part being cleaned and baked! Not needed. left as spares! - DONE!!
spare OSEMS and magnet assemblies were checked and repaired where necessary DONE!!

UI MASS MAGNET HOLDERS reference attached pictures Could not see problem? - DONE!

-ACTION: Before re-suspending the quad work needs to be done on HEPI
-ACTION: The suspension eddy current dampers will be installed by Janeen next week
-ACTION: One global control magnet assembly has to be added.
-ACTION: If the quad is still locked down it will have to be re-suspended, reference notes from Calum.

ELECTRONICS & LED's (out of date refer to work by Ben Abbott)

Status. 12 LC at Top mass, 4 GC at Pen mass (Now 3!) and 4 at UI mass, could be cabling issue, see below?
-ACTION: Ben to act as investigator & to contact Honeywell! (Stuart offering help!)
a) Noise on global control at pen stage?

b) wiring to UI mass osems? (At first we thought it was LED but after replacing with 2 osems thoughts moved to something else?) ALL LED's AT UI MASS NOW WORKING!

c) Washer a useful addition behind magnet on pen mass to make alignment easier!

d) Should we install a bleed wire?
e) LED drive (GEO electronics) being replaced?
f) side osem main chain - cut wire? - OSEM REPLACED!!

Repair of electronics being carried out by Jay!
ACTION: (Brett / Rich) Use ESD transfer functions to investigate shielding questions?