HARP-NEF Front End Assembly · - Inner Surfaces of Each Prism Pair Parallel Mounted & Perpendicular...

HARPS-NEF PDR and TIMDecember 6 & 7, 2007

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HARP-NEFFront End Assembly

HARPN Front End AssemblyHARPN Front End Assembly

( w/ Partial Cover Plates )

Calib Fibers

Science Fibers


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Roger Eng

December 6, 2007


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1. Atmospheric Dispersion Compensator (ADC) Assy

2. Tip Tilt Mirror & Stage Assy

3. Guide Camera & Re-Imaging Optics Assy

4. Calibration Light Projection Optics Assy

5. Calibration Fibers Assy

6. Calibration Fold Mirror Translation Assy

7. Neutral Density Filter

8. Focal Plane Fibers Assy

1

2

4

5

3

6

7

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HARPN Front End w/ Partial Cover Plates


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Atmospheric Dispersion Compensator (ADC) Assy

- 2 Prism Pairs in Assembly

- Each Prism Pair – Glass Material:Glass 1 : OHARA PBL6YGlass 2 : OHARA S-FSL5Y

- Inner Surfaces of Each Prism Pair Parallel Mounted &Perpendicular to Optical Axis

- Prism Pairs Counter Rotate fromEach Other

- Rotating Motion -Ring & Pinion Gears and Drivenby NEMA-17 Stepper Motors

- Rotary Encoder w/ Home Switch per Prism Assy for Positioning Control

ADC Assy ( Telescope Side )

ADC Assy ( Front End Side )

FWD Prism Pair

AFT Prism PairDrive Motor FWD Prism

Drive Motor AFT Prism


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Mechanism – ADC Assy

• Requirement:

Controlled Counter Rotating Motion between Both Prism Pairs

• Accomplished:

Counter Rotating Motion -Ring & Pinion GearDriven by Stepper Motor w/ Rotary Encoder & Home Switch Respectively

• Angular Positioning Accuracy:

Requirement: +/- 0.50 Degree Capability: +/- 0.14 Degree

FWD Prism Pinion & Ring Gear Drive

AFT Prism Pinion & Ring Gear Drive


6

Tip-Tilt Mirror & Stage Assy

• Tip-Tilt Mirror to Re-Direct Telescope Light to Focal Plane Fibers & to Compensate Guiding Errors

• Mirror is Elliptical Shape, 190 mm x 140 mm

• Mirror Bonded on Interface Plate which is Mounted on Tip-Tilt Stage

• Mirror and Stage Assy Mounted on Rigid Structure of Front End Support

• Tip-Tilt Stage & Controller:

By Physik Instrumente ( PI )Stage – P558 TCDController – E710Both Are Off the Shelf Items

Tip-Tilt Stage

Tip-Tilt Mirror

Mirror & Stage Mount Plate


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Guide Camera & Re-Imaging Optics Assy

• For Objects Acquisition, Centering & Guiding of the Telescope

• Guide Camera Design – Heritage

Projects: TRES &MAGELLAN

• A Self-Contained Unit with:

Vacuum WindowVacuum PortCCD Thermal Electric Cooler

• Re-Imaging Optics Group –

Canon - EF 100 mm, f/2.8 Macro USMOff the Self Commercially Available UnitRemotely Adjustable Focus Capability

Guide Camera Assy

Re-Imaging Optics

Camera & Optics Mount


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Mechanism - Guide Camera & Re-Imaging Optics Assy

• Requirement:

Focus Adjustment forGuide Camera Re-ImagingOptics Group

• Accomplished:

Focus Motion –Timing Belt & SprocketDriven by Stepper Motorw/ Rotary Encoder & Home Switch


Requirement: +/- 1.00 Degree

Capability: +/- 0.42 Degree

Guide Camera Assyptics

Step Motor w/ Encoder

Re-Imaging O

Focus Belt & Pulley Drive

Camera & Optics Support Structure


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Calibration Light Projection Optics Assy

• Heritage of HARPS at La Silla Design

• Located Between Calibration Fibers and Calibration Fold Mirror

• Contains 2 Separate Optical Paths of 2 Calibration Beams @ 16 mm Apart

• 2 Sets of Identical Optics –

Entrance & Exit Sets

• Entrance Lens Adjustable by Linear & Rotational Motions

• Pupil Mask Installed at End of Entrance Lens Mount Tube

• Exit Lens Sets Fix Mounted

• Both Calibration Light Beams Contained in the Projection Optics Housing Adjustable Bi-Directionally by Eccentric Cam Motions

Projection Optics Beam Housing

Entrance Optics

Exit Optics

Optics Holders Provide Rotational & Linear Adjustment


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Calibration Fibers Assy

• Heritage of at La Silla Design & A Direct Duplication

• Consists of 2 Fibers @ 16 mm Apart

• Each Calibration Fiber Adjustable Tri-Directionally with Micrometer Head Fine Tuning

• Calibration Light Source - Located Remotely Away from Telescope & Instruments

• Hollow Cathode Lamps & Halogen Lamp Provide Visible Light Source Through Calibration Fibers to the Focal Plane Fibers

• Fiber Illuminator to Provide External Light Source

HARPS - South Calibration Fibers Assy

Calibration Fiber Location


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Calibration Fold Mirror Translation Assy

• Fold Mirror Steers Calibration Light Onto the Focal Plane Fibers

• All 4 Configurations Achieved by Linear Motion Translation to Selected Position of Mirror

• Linear Motion Components:THK Linear Motion Stage Spur Gears & CouplingNEMA-17 Stepper Motor Rotary Encoder & Limit Switches

Calibration Fold Mirror

Step Motor w/ Encoder

THK Stage

Calibration Fold Mirror Translation At True Location


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Mechanism – Calibration Fold Mirror Translation

Requirement:

Four Configurations –1. All Sky Light 2. Sky Light & Calibration Light3. Both Calibration Light4. Sky Light & Other Calibration Light

Accomplished:

All Four Configurations Met –Translation Stage to Move Calibration Fold Mirror to the Appropriate Position

Translation Motion Driven by Step Motor w/ RotaryEncoder & Limit Switches for Homing & Safety

Linear Positioning Accuracy:

Requirement: +/- 0.005 mmCapability: +/- 0.0025 mm

( Based on 10 mm Lead Screw Pitch of Drive Motor )

Config. 1

Config. 2

Config. 3

Config. 4


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Neutral Density Filter

• Located Between Calibration Fibers & Projection Optics

• Mounted Perpendicular to the Calibration Light Beams

• Allows For Adjustments of Flux Exposure of a Calibration Source

• Directly Coupled and Driven by NEMA-17 Stepper Motor through Reduction Gear Head, w/ Home Reference & Rotary Encoder for Accuracy

• Variable Neutral Density Filter:

Reynard CorporationSubstrate: BK-7176 mm Diameter x 2 mm Thick

Variable Neutral Density Filter

Step Motor

w/ Gear Head w/ Encoder


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Mechanism – Neutral Density Filter

• Requirement:

Adjustment of the Flux of a Calibration Source Injected intothe Focal Plane Fibers

• Accomplished:

A Variable Neutral Density Filteris Mounted In Line of CalibrationSource, Driven by Stepper Motorw/ Rotary Encoder & Home Switch


Requirement: +/- 0.10 Degree

Capability: +/- 0.01 Degree ( w/ Gear Reduction )

Neutral Density Filter

Direct Drive Step Motor w/ Gear Head & Encoder


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Focal Plane Fibers Assy

• Heritage of HARPS at La Silla Design

• 2 Fibers Separated by 16 mm

• Fibers Mounted Parallel in Housing Through 2 Pierced Holes

• Angled Reflective Mirror on Front Face of Housing

• Angled Mirror Re-Directs Light from Telescope to the Guide Camera Through Its Front End Lens Group

• Fiber Protector for Protection of theFocal Plane Fibers When Instrument Not In Use

Focal Plane Fiber Holder At True Location

Angled Reflective Surface

Focal Plane Fiber Holder


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Mechanism – Focal Plane Fiber Protector

Focal Plane Fibers Protected

Focal Plane Fibers Exposed

Fiber Protector

Material: Delrin, Black•Requirement:Provide Protection to Science Fibers when not in Use

•Accomplished:A Protective Shield Rotated into Position to Shield the Fiber Head, Driven by a Stepper Motor w/ Rotary Encoder & Home Switch

•Angular Positioning Accuracy:Requirement: +/- 2.0°Capability: +/- 0.9°


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Front End Assembly Handling

• ADC Installation

- Handled Manually- Mechanical Handles Provided- Standard Hardware & Tools Used

• Front End Assembly

- Mechanical Handles Provided forBuild-Up Handling

- Lift Rings & Slings Provided for Hoist Lift & Handling

- Facility Hoist and Man Lift Used for Integration Installation

- Standard Hardware and Tools Used

ADC Assembly

Mechanical Handles for Manual Handling

Front End Assembly ( w/o ADC )

Hoist Ring

Manufacturer: JergensCapacity: 1900 kg ea

Hoist Point

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HARP-NEF Front End Assembly · - Inner Surfaces of Each Prism Pair Parallel Mounted & Perpendicular...

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