[email protected] Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS Undulator Systems

LCLS Undulator Systems Review, 3-4 March 2004LCLS Undulator Systems Review, 3-4 March 2004 Robert Ruland, SLACRobert Ruland, [email protected]@slac.stanford.edu

Linac Coherent Light Source Stanford Synchrotron Radiation LaboratoryStanford Linear Accelerator Center

Magnetic Measurements and Alignment

Robert Ruland & Zack Wolf

Magnetic Measurements and Alignment

Robert Ruland & Zack Wolf

Magnetic MeasurementsImplementation of MMFUndulator TuningFiducialization

Overview of Alignment Strategy

Magnetic MeasurementsImplementation of MMFUndulator TuningFiducialization

Overview of Alignment Strategy

I would like to acknowledge Isaac Vasserman’s and Joachim Pflüger’s indispensable help and expert advice. I would like to acknowledge Isaac Vasserman’s and Joachim Pflüger’s indispensable help and expert advice.

http://www-ssrl.slac.stanford.edu/



SLAC LCLS Magnet Measurements Facility

SLAC presently does not have a facility to perform the magnetic measurements tasks necessary for LCLS with the required accuracy: Need to build new facility.Proposed Location: Bldg 81, about 0.8 km away from tunnel

Sufficient power for CCNo heavy machinery nearbyNo space constraints

SLAC presently does not have a facility to perform the magnetic measurements tasks necessary for LCLS with the required accuracy: Need to build new facility.Proposed Location: Bldg 81, about 0.8 km away from tunnel

Sufficient power for CCNo heavy machinery nearbyNo space constraints




Construction & Design Goals

FundingLLP Funds Building & Climate Control K$1200 + K$300 ContingencyMeasurement Equipment K$784 +K$336 Contingency

Construction ScheduleT1 June 04 (Engineering)T2 Oct 04 (Contract Procurement)T3 Jan 05 (Construction)Beneficial Occupancy July 05

Design SpecificationsTemperature stability of 0.1ºC, short term temperature swings of up to 0.3 ºC with less than 1 hour duration are acceptableFull set of specs: LCLS-TN-04-1 Z. Wolf, R. Ruland, "Requirements for the Construction of the LCLS Magnetic Measurements Laboratory“. The specs were reviewed and approved by our advising experts I. Vasserman, APS and Dr. Pflüger, DESY

FundingLLP Funds Building & Climate Control K$1200 + K$300 ContingencyMeasurement Equipment K$784 +K$336 Contingency

Construction ScheduleT1 June 04 (Engineering)T2 Oct 04 (Contract Procurement)T3 Jan 05 (Construction)Beneficial Occupancy July 05

Design SpecificationsTemperature stability of 0.1ºC, short term temperature swings of up to 0.3 ºC with less than 1 hour duration are acceptableFull set of specs: LCLS-TN-04-1 Z. Wolf, R. Ruland, "Requirements for the Construction of the LCLS Magnetic Measurements Laboratory“. The specs were reviewed and approved by our advising experts I. Vasserman, APS and Dr. Pflüger, DESY




Magnetic Measurements Capabilities

Undulator Test Bench 7 mUndulator Prototype Bench 4 mHall Probe Calibration SystemQuadrupole Field Meas. BenchQuadrupole Fiducialization PlatformFiducialization CMM 4.2 mTemp. Storage, 10 Undulator Segments

Undulator Test Bench 7 mUndulator Prototype Bench 4 mHall Probe Calibration SystemQuadrupole Field Meas. BenchQuadrupole Fiducialization PlatformFiducialization CMM 4.2 mTemp. Storage, 10 Undulator Segments




Undulator Test Bench

Implementation ScheduleUndulator delivery commences in May 2006Expected delivery of bench and components in August 2005

Too late to complete integration, software development, testing and commissioning by 5/06, Upgrade 4m bench obtained from APS with equivalent hardware as 7m bench to serve as test bed for software development and procedure testing. New components:

Etel Linear Motor with integrated Heidenhain encoderX and Y Cross-slides with Heidenhain encodersServo Motors and controllersHall Probes and Hall Probe Calibration System (will also be used with 7m bench)

Implementation ScheduleUndulator delivery commences in May 2006Expected delivery of bench and components in August 2005

Too late to complete integration, software development, testing and commissioning by 5/06, Upgrade 4m bench obtained from APS with equivalent hardware as 7m bench to serve as test bed for software development and procedure testing. New components:

Etel Linear Motor with integrated Heidenhain encoderX and Y Cross-slides with Heidenhain encodersServo Motors and controllersHall Probes and Hall Probe Calibration System (will also be used with 7m bench)




Undulator Test Bench Design

The LCLS Bench is modeled after the APS and the more recent DESY 12m bench.

Critical Design ParametersThe proposed critical design parameters for the LCLS Magnetic Measurements Bench were reviewed by Isaac Vasserman, APS, and Joachim Pflüger, DESY. Field measurement precision of 1.5*10-4 required, this translates for the LCLS undulator into a Hall probe position accuracy of

dZ 3 µmdX 300 µmdY 60 µm

These values drive the bench design as they represent the total error budget.Bench Travel Length, Undulator 3.4m + carriage 1m + zero gauss chamber 0.5m + 2*fiducialization fixture 1m + 2*over travel 0.6m = 6.5 m

The LCLS Bench is modeled after the APS and the more recent DESY 12m bench.

Critical Design ParametersThe proposed critical design parameters for the LCLS Magnetic Measurements Bench were reviewed by Isaac Vasserman, APS, and Joachim Pflüger, DESY. Field measurement precision of 1.5*10-4 required, this translates for the LCLS undulator into a Hall probe position accuracy of

dZ 3 µmdX 300 µmdY 60 µm

These values drive the bench design as they represent the total error budget.Bench Travel Length, Undulator 3.4m + carriage 1m + zero gauss chamber 0.5m + 2*fiducialization fixture 1m + 2*over travel 0.6m = 6.5 m




Bench Specifications

Total travel length in Z 6500 mm.Make carriage as long as cost wise reasonable to minimize yaw, at least 1000 mmMake bench cross-section as large as reasonable, min 800 mm wide, 500 mm highTravel length in X as much as bench width permits, min 100 mmTravel length in Y: 100 mm or more if w/o loss of accuracyGranite base straightness in Z and X: <10 µm, if possible 5µmPosition accuracy at probe tip in Z, X, Y: 3 µm, 10 µm, 10 µmZ-axis drive linear motor with 1 µm positioning resolutionX, Y axes drive lead-screw with 1 µm positioning resolutionNo stepping motor on any axisZ position measurement with incremental encoder type Heidenhain LIDA, a second encoder on opposite side of bench could be considered to monitor yaw rotation of carriage, Agilent interferometer could be integrated for encoder calibration)X, Y axes motion measured with Heidenhain glass scale encodersPerpendicularity of X and Y axes to be better than 0.1 mradProbe axis be equipped with rotary stage with 0.01º resolution and 4-axes goniometerSupport bench on foundation separate from laboratory floorSupport undulator independent from bench on common foundationSupport cable carrier independent from bench on common foundationEquip cable carrier with drive system synchronized as slave to Z-axis drive

Total travel length in Z 6500 mm.Make carriage as long as cost wise reasonable to minimize yaw, at least 1000 mmMake bench cross-section as large as reasonable, min 800 mm wide, 500 mm highTravel length in X as much as bench width permits, min 100 mmTravel length in Y: 100 mm or more if w/o loss of accuracyGranite base straightness in Z and X: <10 µm, if possible 5µmPosition accuracy at probe tip in Z, X, Y: 3 µm, 10 µm, 10 µmZ-axis drive linear motor with 1 µm positioning resolutionX, Y axes drive lead-screw with 1 µm positioning resolutionNo stepping motor on any axisZ position measurement with incremental encoder type Heidenhain LIDA, a second encoder on opposite side of bench could be considered to monitor yaw rotation of carriage, Agilent interferometer could be integrated for encoder calibration)X, Y axes motion measured with Heidenhain glass scale encodersPerpendicularity of X and Y axes to be better than 0.1 mradProbe axis be equipped with rotary stage with 0.01º resolution and 4-axes goniometerSupport bench on foundation separate from laboratory floorSupport undulator independent from bench on common foundationSupport cable carrier independent from bench on common foundationEquip cable carrier with drive system synchronized as slave to Z-axis drive




Implementation Schedule




Undulator Prototype Bench




Undulator Test Bench Implementation




Undulator Fiducialization

Proposed Procedure

Align the poles of the undulator to the test stand using capacitive sensors.Move the Hall probe to the mid-plane of the undulator. This is done by performing scans at different heights, fitting the K value as a function of y, then finding the y value that minimizes K.Tune the undulator. Fine tuning of the gap is required in advance.Repeat step 2 to make sure the mid-plane hasn’t moved during tuning.Scan at different x positions. Move to the x value that gives the desired K.The Hall element is now moving on the ideal beam axis of the undulator. Move to pointed magnets attached to the undulator ends.Find the offset from the ideal undulator axis to the center of the pointed magnets.Move the undulator to a CMM.Locate the pointed magnets relative to tooling balls on the undulator.Apply the offset from the pointed magnets to the ideal beam axis.

Proposed Procedure

Align the poles of the undulator to the test stand using capacitive sensors.Move the Hall probe to the mid-plane of the undulator. This is done by performing scans at different heights, fitting the K value as a function of y, then finding the y value that minimizes K.Tune the undulator. Fine tuning of the gap is required in advance.Repeat step 2 to make sure the mid-plane hasn’t moved during tuning.Scan at different x positions. Move to the x value that gives the desired K.The Hall element is now moving on the ideal beam axis of the undulator. Move to pointed magnets attached to the undulator ends.Find the offset from the ideal undulator axis to the center of the pointed magnets.Move the undulator to a CMM.Locate the pointed magnets relative to tooling balls on the undulator.Apply the offset from the pointed magnets to the ideal beam axis.




Quadrupole Fiducialization

Finding the axisBased on Vibrating Wire or Pulsed WireHave Pulsed Wire prototype setup. Routinely achieve repeatabilities even in environment with wide temperature swings of better than 5 µmAlso haveVibrating Wire prototype set-up. It promises better yaw and pitch resolution. Implementation based on setup by Dr. Temnykh from Cornell

Transfer onto quadrupole fiducialsUse Wire Finders (developed for VISA) to locate wire and reference to its tooling ballsUse Coordinate Measurement Machine (CMM) to transfer information from WF to Quad fiducials.Vibrating Wire system will be mounted onto optical table which can be set-up on undulator fiducialization CMM

Finding the axisBased on Vibrating Wire or Pulsed WireHave Pulsed Wire prototype setup. Routinely achieve repeatabilities even in environment with wide temperature swings of better than 5 µmAlso haveVibrating Wire prototype set-up. It promises better yaw and pitch resolution. Implementation based on setup by Dr. Temnykh from Cornell

Transfer onto quadrupole fiducialsUse Wire Finders (developed for VISA) to locate wire and reference to its tooling ballsUse Coordinate Measurement Machine (CMM) to transfer information from WF to Quad fiducials.Vibrating Wire system will be mounted onto optical table which can be set-up on undulator fiducialization CMM




Cradle Assembly

After fiducialization, undulators, quadrupoles, and BPMs as well as the vacuum chamber with its strong back will be assembled into one unit and aligned with respect to each other.Total vertical alignment budget is 50 µm. This is comprised of (adding in quadrature):

Quadrupole offset (20 µm)Quadrupole fiducialization (15 µm)Undulator fiducialization (40 µm)Relative alignment (20 µm)

After fiducialization, undulators, quadrupoles, and BPMs as well as the vacuum chamber with its strong back will be assembled into one unit and aligned with respect to each other.Total vertical alignment budget is 50 µm. This is comprised of (adding in quadrature):

Quadrupole offset (20 µm)Quadrupole fiducialization (15 µm)Undulator fiducialization (40 µm)Relative alignment (20 µm)




Undulator Measurement Schedule

Undulator #1 from vendor A to SLAC July 1, 2006, after initial learning curve schedule accelerated to one undulator every 10 days, undulators from vendor B will follow with a 10 day phase shift.

Undulator #1 from vendor A to SLAC July 1, 2006, after initial learning curve schedule accelerated to one undulator every 10 days, undulators from vendor B will follow with a 10 day phase shift.




Undulator Measurement Schedule, Undulator #1 & 33

Undulator #115 days soaking15 days Magnetic Measurements13 days Fiducialization & Assembly5 days Set-up & Handling

Undulator #3315 days soaking5 days Magnetic Measurements4 days Fiducialization & Assembly1 days Set-up & Handling




Manpower Requirements

The MMF implementation schedule is adjusted to the present staffing in SLAC’s Magnetic Measurements Group and to allow the conventional work to continue.LCLS Development

2 Senior Physicists1.5 Engineering Physicists1 Metrology Engineer2 Technicians

Conventional Work1 Senior Physicist0.5 Engineering Physicist1 Technician1 Research Assistant

Will be able to handle LCLS Production Measurements with existing manpower, supplemented with help from the Alignment Engineering and Quality Inspection Groups. There is no other significant competing work scheduled.

The MMF implementation schedule is adjusted to the present staffing in SLAC’s Magnetic Measurements Group and to allow the conventional work to continue.LCLS Development

2 Senior Physicists1.5 Engineering Physicists1 Metrology Engineer2 Technicians

Conventional Work1 Senior Physicist0.5 Engineering Physicist1 Technician1 Research Assistant

Will be able to handle LCLS Production Measurements with existing manpower, supplemented with help from the Alignment Engineering and Quality Inspection Groups. There is no other significant competing work scheduled.




Global Alignment

BO of the undulator hall is earlier (01/07) than BO of LTU cannot establish direct connection to LINAC coordinate systemEstablish global alignment reference by connecting undulator hall reference network through vertical survey shafts at both ends of hall to surface monumentsSurface monument coordinates are determined using differential GPS and levelingExpected tolerance for global coordinates in undulator hall: dX, dY, dZ < 1 mm

BO of the undulator hall is earlier (01/07) than BO of LTU cannot establish direct connection to LINAC coordinate systemEstablish global alignment reference by connecting undulator hall reference network through vertical survey shafts at both ends of hall to surface monumentsSurface monument coordinates are determined using differential GPS and levelingExpected tolerance for global coordinates in undulator hall: dX, dY, dZ < 1 mm




Component Alignment Procedure

Proposing to use same alignment sequence as successfully done with PEPII and SPEAR3:

Install and measure networkMark Anchor positions on floorDrill, set Anchors and install mounting platesPre-align mounting plates to 0.5 mm in X, Y and ZInstall Granite tables which are referenced to mounting platesAlign mounting tables in Y to 100 µmAlign Cam Mover pairs in X to 200 µmInstall Hydrostatic Level SystemInstall Undulator Cradle AssemblyInstall Stretched Wire Monitoring System Fine align assemblies Y to 50 µm, X to 80 µm

Proposing to use same alignment sequence as successfully done with PEPII and SPEAR3:

Install and measure networkMark Anchor positions on floorDrill, set Anchors and install mounting platesPre-align mounting plates to 0.5 mm in X, Y and ZInstall Granite tables which are referenced to mounting platesAlign mounting tables in Y to 100 µmAlign Cam Mover pairs in X to 200 µmInstall Hydrostatic Level SystemInstall Undulator Cradle AssemblyInstall Stretched Wire Monitoring System Fine align assemblies Y to 50 µm, X to 80 µm




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Documents

[email protected] Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS Undulator Systems