GLAST LAT Project March 2005 LAT Environmental Test

GLAST LAT Project March 2005 LAT Environmental Test Planning Meeting 14 -16 March 2005 Environmental Test MGSE Design Concepts Rev 1 Martin Nordby Systems Integration Mike Foss 1

GLAST LAT Project March 2005 Outline • • • Environmental test sequence Sine Vibe test MGSE and configurations EMI/EMC test MGSE Acoustic test MGSE T-Vac test MGSE and configuration High-Bay operations – Options for rotating the LAT – Transport Container – Cart design concepts Systems Integration 2

GLAST LAT Project March 2005 Environmental Test Sequence: Working Baseline Receive, Unpack Reference CPT Performed at SLAC C Sine Vibe L L Modal Survey T-Bal L A Install Radiators T-Cycle C M L L C Final CPT EMI/EMC L Remove Radiators C Acoustic L Weight, CG L Pack LAT A Ship to GD Aliveness Limited Performance C Comprehensive Performance M Muon Survey C Systems Integration 3

GLAST LAT Project March 2005 Sine Vibe: Test Configuration LAT appears to clear rotation of expander head Test Interface Plate fits completely on expander head Check on clearance to off-load frame LAT on Expander Head (with auxiliary support) LAT on Shaker Table Systems Integration 4

GLAST LAT Project March 2005 Sine Vibe: Test Configuration (cont. ) Check on clearance and access around underside of GPR Systems Integration Check on total height of 4 x 4 Lift Fixture lifting GPR over top of ACD LAT on Expander Head Showing GPR Lift with 4 x 4 Lift Fixture 5

GLAST LAT Project March 2005 Sine Vibe: MGSE Concept • Test Interface Plate – Provides single interface for LAT in all test configurations – Mimics SC top deck – Ensures accurate alignment of SC flexures Plate serves only to accurately position brackets, not to carry vibe loads Test Interface Plate with SC Flexures (on expander head) Mount brackets transfer load from flexure directly to table Systems Integration Test Interface Plate with SC Flexures (on slip table) 6

GLAST LAT Project March 2005 Sine Vibe: MGSE Mount Detail Systems Integration 7

GLAST LAT Project March 2005 Sine Vibe: Mechanical Issues • • Known issues to be worked – Clearance to off-load frame on expander head – Verify that Test Interface Plate fits completely on expander head – Verify that LAT clears bracket parts on slip table – Complete and release drawings/model of slip table and expander head – Complete detailed design and analysis of TIP and flexure mount brackets – Check on hook height in vibe room to ensure we can remove GPR when LAT is on expander head – Develop paper doll work-up to verify we have floor space for 2 carts, GPR, and 4 x 4 Lift Fixture – Develop requirements for Radiator simulator for sine vibe – Lay out EGSE cable routing and locate EGSE crates – Identify what contamination and humidity control is needed in vibe facility MGSE Requirements List – Test Interface Plate • • Light enough to allow for using GPR to lift LAT+TIP within its current rated load (3000 kg) Accommodates Spectrum-specified flexure mounting procedures – Contamination/environmental Systems Integration 8

GLAST LAT Project March 2005 Sine Vibe: Action Item Status • • • V 100: strain gauges on SC flexures – They will fit easily on flexures using TIP interface concept – OK to leave in place for acoustic testing and LAT turn-over, if desired V 101: clearance to rotate shaker head – Appears to be adequate clearance to the LAT – Current plan is to set LAT back on cart while shaker is being re-configured, so this action is moot V 102, V 114: provide CAD file of vibe table and facility – Second draft of table, expander head, and entire vibe set-up, and facility in-hand at SLAC – Final check and release in-process V 110: SC interface definition from Spectrum – Test Interface Plate is intended to allow us to integrate SC flexure just like Spectrum does – Need to work with GSFC and Spectrum to transfer detailed procedures from Spectrum for our use V 115: Logistics of using flexures and TIP – TIP and flexures will be mounted at SLAC, and used for transport and all tests – This means that they have to be light enough so GPR can pick up the LAT+TIP load V 117: LAT cleanliness during vibe testing – We are carrying an option for a Dust Tent that can be moved around with the LAT – Still need to specify what cleanliness requirements are Systems Integration 9

GLAST LAT Project March 2005 EMI/EMC Test: Test Configuration and MGSE This configuration is identical to Acoustic Test configuration Clear access to perimeter of LAT for placing antennas Systems Integration LAT on Test Stand (Vertical Configuration) 10

GLAST LAT Project March 2005 EMI/EMC Test: Mechanical Issues • • Known issues to be worked – Identify antenna size and placement and check orientations around LAT – How to get LAT on Test Stand into chamber – Chiller lines electrical resistance to ground along lines: TBD – Antenna placement/angles around LAT: for finalizing MGSE footprint – Contamination: cleanliness during move and in chamber; humidity under any clean tent – Test Stand grounding: how to ground test stand Requirements List – Provide grounding caps for thermal and accel instrumentation – Chiller lines electrical resistance to ground along lines: TBD – Antenna placement/angles around LAT: for finalizing MGSE footprint – Contamination: cleanliness during move and in chamber; humidity under any clean tent – Test Stand grounding: how to ground test stand Systems Integration 11

GLAST LAT Project March 2005 EMI/EMC Test: Action Item Status • • • E 103: terminate test instrumentation at EMI Shield for thermal and accel’s – Grounding caps will be available for this instrumentation E 110: chiller lines need electrical break – No progress, but this should not be an issues – Need definition of resistance to ground along lines E 112, E 113: moving LAT to and into chamber – Test Stand concept is much more transportable than previous design – Plan to use Cart into chamber, or add pads for casters or air-bearings – No progress on developing route from High-Bay E 114: develop CAD model of chamber – First draft sent to SLAC – Plan to complete and release next E 115: work out needed antenna orientations around MGSE – Current MGSE leaves LAT much more open around base perimeter – Still need requirements on antenna placement to finalize MGSE design E 116: clean tent around LAT in EMI chamber – Incorporated provision for tent on Test Stand, but no progress on this – Still need to define cleanliness requirements Systems Integration 12

GLAST LAT Project March 2005 Acoustic Test: Test Configuration and MGSE This configuration is identical to EMI Test configuration Test Interface Plate mounts LAT to Test Stand Facsimile SC struts support Radiators with comparable stiffness Need to establish required height off ground—can be handled by a separate stand Systems Integration LAT on Test Stand (one Radiator removed 13

GLAST LAT Project March 2005 Acoustic Test: Mechanical Issues • • Known issues to be worked – Is a dust tent needed around LAT in acoustic chamber – What type of panels are needed in/around LAT to simulate SC response – Accommodation for moving Test Stand over ½” door sill – How high does Radiator need to be off the floor: affects Test Stand spacer height MGSE Requirements List – Radiator strut stiffness: need input from Spectrum – Contamination: is tenting needed; humidity Systems Integration 14

GLAST LAT Project March 2005 Acoustic Test: Action Item Status • • A 101: supporting LAT at SC flexures vs Radiator Mount Brackets – No longer an issue. Test Stand concept preserves flight-interface A 102: add sheet under LAT – Is this needed and/or feasible – May not work given Test Stand design, since it blocks free-dropping of particulates A 104: Radiator support strut stiffness – Need to get stiffness from Spectrum – Test Stand can accommodate/tune support strut mount to simulate flight-like stiffness A 106: horizontal vs vertical orientation – Test Stand is designed to allow for either, but default is vertical – Open issue is how far off the ground the bottom of the Radiators should be A 109: LAT clean tent in acoustic chamber – Test Stand can accommodate a clean tent – Need to work the requirements for this A 110: moving LAT into chamber over ½” door sill – Test Stand can accommodate large casters or air bearings – Need to add accommodation for multiple positions of these, since Stand only has 4 feet A 111: acoustic chamber CAD model – Preliminary layout sent – Next step is to complete layout and release it Systems Integration 15

GLAST LAT Project March 2005 Thermal-Vacuum Test: Test Configuration Port plate for LAT elec, gas feedthroughs LAT rolls into chamber on floor Systems Integration LAT on Test Stand Oriented Horizontally 16

GLAST LAT Project March 2005 Thermal-Vacuum Test: Test Configuration Chamber Plan View (PDF file) SIIS, thermal sensor cable routing Front View with Chamber Cut Away View from Inside Chamber Systems Integration 17

GLAST LAT Project March 2005 Thermal-Vacuum Test: MGSE Concept Upper extension beams are used for lifting LAT into place, then removed Radiators mounted to Test Stand in vertical orientation Extension beams double as support legs Systems Integration LAT on Test Stand (Horizontal Configuration) 18

GLAST LAT Project March 2005 Thermal-Vacuum Test: MGSE Concept (cont. ) ACD Sink Plates on an independent support frame Possible hydraulic assist for rotating detaches for T-Vac LAT on Test Stand (Horizontal Configuration) Systems Integration 19

GLAST LAT Project March 2005 Thermal-Vacuum Test: Mechanical Issues • • Known issues to be worked – Trapped air volumes: contamination issue – Thermal stability of support: how level will it keep the LAT and what is requirement – Sink panel design and support: 5 ACD, 3 SC, 2 Rad Requirements list – Leveling: what is accuracy and precision needed for heat pipes; any stability req’s? – Test Stand allowed temps: temperature range that Test Stand may see – Allowed parasitic conduction and radiation to/from Test Stand other MGSE Systems Integration 20

GLAST LAT Project March 2005 Thermal-Vacuum Test: Action Item Status • • • T 102, T 114: clearances in and around T-Vac chamber and chamber dimensions – Chamber model delivered to SLAC and incorporated – Clearance evaluations are in the works T 110, T 137, T 138: define leveling requirements for heat pipes, any muon surveys; inclinometers needed? – No progress T 118: MGSE temperature requirements – Agreed to keep Test Stand in a ~-10—+20 deg. C range – Still working details of heating/cooling/isolation needed T 126: agree to structural supports of LAT in T-Vac – Test Stand provides flight-like structural and thermal interface for LAT – Eliminated all options using GPR T 127: develop T-Vac STE list – Started list of MGSE, but not complete Systems Integration 21

GLAST LAT Project March 2005 High-Bay Operations • • • LAT handling Options for rotating the LAT Other MGSE – Transport Container – Carts – Dust Tent Lists – Known issues to be worked – Open issues – Requirements list Action item update Systems Integration 22

GLAST LAT Project March 2005 LAT Handling and Lifting Extension beams bolt to Test Stand to allow for over-the-cg lift Will likely need spreader bars or frame to close out extensions LAT on Test Stand with Extension Beams for Lifting Systems Integration Need 4 pick points for crane lift in horizontal configuration LAT on Test Stand with Extender Beams Horizontal Lift and Feet 23

GLAST LAT Project March 2005 Options for Rotating the LAT • • The LAT needs to be rotated twice; both times with the Radiators attached – Rotate down to +Z-horizontal in preparation for T-Vac testing – Rotate back up to +Z-vertical after T-Vac, before removing Radiators Three options for rotating LAT – Rotate over-center (PDF file) • • Crane pick points to hold LAT while it rotates over-center Fixed pivot on Test Stand Uses hydraulic-assist damping – Rotate under-pivot • • • Fixed pivot on Test Stand CG swings down, under the pivot point to prevent over-center problems Requires spacer stands – Two-hook crane pick (PDF file) • • Use two crane hooks Rotate LAT while hanging Pivot points built into Test Stand Systems Integration Hydraulic cylinders are passive dampers, not active assist devices LAT Being Rotated over-center rotation using hydraulic damping 24

GLAST LAT Project March 2005 Other MGSE for LAT Handling Operations Systems Integration 25

GLAST LAT Project March 2005 High-Bay Operations: Mechanical Issues • Known issues to be worked • Requirements list Systems Integration 26