1K. Artoos CTC 27/07/2010

News from Stabilisation WGMain Beam Quadrupole Stabilisation

News from LAPP

News from CEA

News from CERN

2K. Artoos CTC 27/07/2010

News from LAPP

• Meeting 15th July (Andrea, Claude, Kurt)

• MBQ Eigen mode analysis:http://hal.in2p3.fr/in2p3-00480244/fr/Report:

Pole modal measurements ongoing

Free-free 279 Hz first bending frequency. Some uncertainties for supported MBQ (depends on boundary conditions). First bending modes around 250 Hz

• Active foot :PI capacitive gauges purchasedActuators installed + testedRole and behaviour elastomer not fully understood yetFirst stabilisation results foreseen in September

• More regular meetings LAPP/CERN planned from September on Closer collaboration to improve “critical mass”

• Cross check between seismometer and MONALISA

• Decision « baseline stabilisation MBQ » for CDR ?

3K. Artoos CTC 27/07/2010

News from IRFU CEA SACLAYPurchase of SIOS Triple axis interferometer 0.1 nm resolution

Borrowed device now available

Final delivery in September

Measurement through 3 mm hole confirmed

Measurement of pole tip vibrations with respect to yokeMeasurements vibrations coil and yoke water coolingCalibration actuators + hexapodCalibration tilt meters

Preparation measurements started (mirrors etc)

4K. Artoos CTC 27/07/2010

News from CERNOverall approach and work plan : See CTC # 22 Talk C. Hauviller

Claude HauvillerKurt ArtoosChristophe CollettePablo Fernandez CarmonaMichael GuinchardStef JanssensAndrey KuzminRaphael LeuxeAnsten Slaathaug

This talk: status, ongoing work and outlook

5

1. Stabilisation single d.o.f. with small weight (“membrane”)

End April CERN 2010

K. Artoos IPAC10

Steps toward performance demonstration RIGID option

Piezo actuator ( PI™): Resolution 0.1 nm Stiffness 24 N/µmMeasured vertical resonant frequency ~ 300 Hz

2.5 kg

Objective reached

6K. Artoos CTC 27/07/2010

Input from Pablo Fernandez Carmona:

Systematic study and improvement of noise levels:

Power supply seismometers

Cabling to seismometer

Noise level acquisition systemsNoise level output

Result last week on membrane:

0.6 nm at 1 Hz from 2 nm

1 nm at 1 Hz from 5 nm

P. Fernandez CarmonaS. JanssensC. Collette

« Nano-positioning »

Or “Modify position quadrupole in between pulses (~ 5 ms) “

“Range 10 μm, steps 10 to 50 nm, precision 2nm ”

Demonstration nano-positioning single d.o.f. :

For FREE

10 nm, 50 Hz

S. Janssens

Measured with capacitive gauge 0.1 nm resolution open loop

7K. Artoos IPAC10

< 1 Hz Beam based feedback: BPM + corrector dipoles

Remark: Measuring < 0.1 nm relative displacement

Catalogue products

Steps toward performance demonstration RIGID option

2. Stabilisation single d.o.f. with type 1 weight (“tripod”)

actuator

Preliminary result in noisy environment

S. Janssens

2 rigid feet

No flexural guide yet so can be improved

30 nm at 50 Hz

100 kg

Expected

Requirements for the actuating support

• Stiff• Degrees of freedom: 6 d.o.f. ?

• 0.1 nm resolution vertical• Precision and repeatability 1 – 2 nm

Flexural hinges instead of rotary joints

9K. Artoos IPAC10

Natural frequencies > 200 Hz

Parallel structure

Concept drawing

Piezo actuators

Blocking force 12.5 kNStiffness 480 N/μm *Resolution 0.15 nm

PI P-225.10

• Precise

Integrated sensor 0.3 nm

G

G

G

G

10K. Artoos IPAC10

Design 2 d.o.f. flexural hinge

Number and orientation of legs

K axial : ~ 300 N/μmK α : ~ 200 Nm/rad

Structural stiffness

Induced stresses in piezo

Inclination Resolution, structure stiffness, forces

Number # D.O.F. , COSTResonant frequency

Difficulty assembly

FE model with parameters available

11K. Artoos CTC 27/07/2010

Steps toward performance demonstration RIGID option

3. Stabilisation two d.o.f. with type 1 weight (“tripod”)

Test assembly done, this week assembly with real actuators

12K. Artoos IPAC10

Actuator pairs in same planeBlock longitudinal

Block Roll X- Y guidance

y v

Video modes singularity

13K. Artoos CTC 27/07/2010

Design x-y guide: statusConcept: hyperguided table with 8 flexural beams

Designing for a low x-y rigidity and high longitudinal and torsional rigidity

Type 1

14K. Artoos CTC 27/07/2010

Additional functions x-y guide:

• Add a direct measurement of the x-y displacement with respect to intermediate platform

To replace instrumentation in legsHas a zero position (reference mark on grating) !Sensitivity and noise level does not change with

position (unlike capacitive gauges)Less strict alignment requirements sensorCould become low cost for large serie

LIP 281 Linear encoder 1 nm/TTL

• Introduce the possibility to protect piezo actuators during transport

• Should make it possible to reduce the number of actuators.

• The x-y guides can be built together to form a girder around the magnet as the intermediate platform between alignment and stabilisation

15K. Artoos IPAC10

Alignment :

Stiffness other components: magnet and support

F. LacknerEccentric cams. First prototype based on SLS (PSI)

• Beam height reduced to 620 mm

• Alignment with Eccentric cams at Airy points

• Stabilisation actuator pairs above cams

Ground broadband excitation amplified at support and magnet resonances

16K. Artoos CTC 27/07/2010

Steps toward performance demonstration RIGID option

4. Stabilisation two d.o.f. with type 4 weight

Type 2 to type 4 will be an extension/duplicate of type 1.

Price enquiry for 6 actuators being prepared.

Too late for CDR draft end september.

17K. Artoos CTC 27/07/2010

Stabilisation control strategy Christophe ColletteStef Janssens

Comparison different control/sensor strategies

Contact with seismometer companies to produce a « inertial reference mass » to replace the broadband seismometers or to remove their inconveniences

To be presented in September ISMA conference + ref. MEDSI presentation 2010Force sensing methods at higher frequencies

Controller for 2 degrees of freedom for stabilisation and nano positioning.

Ongoing work:

Improvement stability + increase the performance

Model for 6 degrees of freedom type 4 for interaction with BBF.

Publication in Physical Review, special topics: accelerator and beam.

18C. Collette MEDSI

19K. Artoos CTC 27/07/2010

Sensor characterisation:

« Bungee table » for noise characterisation seismometers

Ansten SlaathaugMichael Guinchard

Characterisation and research noise and sensitivity seismic accelerometers, low noise amplifiers, Conditionners,…

Ongoing:

20K. Artoos CTC 27/07/2010

Vibration source characterisation:

Ongoing:

• Ground excitation by shaker with a known frequency/spectrum and amplitude and propagation measurement in different floors. • Planned measurements surface CMS for final focus

• As soon as MBQ prototype is available we can do measurements with water cooling: vibrometer + LASER interferometer will be available.

Michael GuinchardAnsten Slaathaug

• Possibility to do vibration measurements for module, but Measurement Lab highly loaded with other CERN projects: ressource critical.

• Planned measurements of efficiency passive damping systems for pumps etc.

21K. Artoos CTC 27/07/2010

Conclusions

Steady progress on steps towards demonstration of feasibility.

Not at the same pace as CDR. Importance to have convincing intermediate steps.The schedule is not always in our hands + too many CLIC meetings… (?)

The team put in place begins to pay off, important to keep continuity long enough (WP).

It would help to have a dedicated work space as can be found in other places doing this kind of work: temperature stable, low vibration back ground, « clean » electrical network, cooling water network, lifting and handling,…. ***