GLAST LAT Project I&T Meeting – Jan 29,2004

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GLAST Large Area Telescope: GLAST Large Area Telescope:

MGSE Status Report

Eric GawehnSU-SLAC

I&T MGSE Engineer

egawehn@slac.stanford.edu650-926-3622

Gamma-ray Large Gamma-ray Large Area Space Area Space TelescopeTelescope

GLAST LAT Project I&T Meeting – Jan 29,2004

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MGSE OverviewMGSE Overview

Total of about 30 MGSE items to be produced for LAT integration

• Hardware– In this presentation only the main items will be addressed

• LAT Rotation Stand• LAT Support Fixture for the Grid Perimeter Ring (GPR) • LAT Transport Container• 90º Support for Van de Graaff (VDG) Tests

– Remaining MGSE items are about 50% complete

• Drawings– Critical Path Detail Drawings are 70% complete (goal is to have all

finished by Design Review)– Detailed drawings are 50% complete

• Remainder is being held up until formal stress analysis is completed

GLAST LAT Project I&T Meeting – Jan 29,2004

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LAT Rotation Stand – Personnel Access PlatformLAT Rotation Stand – Personnel Access Platform

• Design Philosophy– Provide more parallel work area in the Integration Hall– Minimize mechanical preparation for Flight work Ops

• Status – Two Concepts for Personal Access Platform are completed

( no major issues at this point)• Primary minimizes impact to work area, but adds about

$17K to Rotation Stand (delays final dwgs by ~ 15 days• Second impacts work area and time for mechanical

preparation Ops and may cost ~ $8K• Issues

– See Concept Views• Views do NOT imply detail dwg maturity; much work to

do

GLAST LAT Project I&T Meeting – Jan 29,2004

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2,743 mm

[ 108 inches ]

Wide

4,420 mm [ 174 inches ] Long

LAT Rotation StandLAT Rotation Stand

Interference with Grid Perimeter Ring is now

being worked out

GLAST LAT Project I&T Meeting – Jan 29,2004

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Heater Control Box Connector ClearanceHeater Control Box Connector Clearance

Heater Control BoxConnectors

Shown De-Mated

0.87”This Connector May Require a 90º Strain

Relief

Grid Perimeter Ring to Grid Bracket

Grid Perimeter Ring

- Z

GLAST LAT Project I&T Meeting – Jan 29,2004

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GPR with Heater Control Box Side ViewGPR with Heater Control Box Side View

GLAST LAT Project I&T Meeting – Jan 29,2004

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A-Frame Rotation Stand with Low Cost PAP*A-Frame Rotation Stand with Low Cost PAP*

* PAP – Pesonnel Access Platform

GLAST LAT Project I&T Meeting – Jan 29,2004

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A-Frame LAT Stand with Low Cost PAPA-Frame LAT Stand with Low Cost PAP

B-33, Rm 104 Integration Hall

Crane Structure

B-33 Beam; Not in Rm

Top Looking Down View

LAT A-Frame Integration

Stand

Low Cost Stand Takes Up Most of

the Rm

GLAST LAT Project I&T Meeting – Jan 29,2004

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Refined Rotation Stand with PAPRefined Rotation Stand with PAP

GLAST LAT Project I&T Meeting – Jan 29,2004

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Box Frame Stand with PAP, SmallBox Frame Stand with PAP, Small

GLAST LAT Project I&T Meeting – Jan 29,2004

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LAT Support Structure; GPRLAT Support Structure; GPR

• Design Philosophy– Bolt together frame with fairly precise bracketry

• Status– Concept is well understood– Stress Analysis completed and shows compliance to EWR

127.1 ( > 5 x against Ultimate )• The bracket clevice analysis needs 1 final iteration

Issues– Interference with heater control box connector is resolved

• Need to assess access for removal of Clevice Pin

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GPR CompleteGPR Complete

• Image in work

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LAT Transport ContainerLAT Transport Container

• Design Philosophy– Attempting to fit in 88” Truck

• Taller and more narrow version adds $20-30K for engineering and mass plate

– Have a concept that works but requires additional ~ $20K for non-std truck width for cross-country ride to NRL• Isolation system appears satisfactory

• Work in progress– Layout is in work; may not be available next week– Vibration report by next week – (First Iteration, expect

another iteration for final design to follow) • Issues

GLAST LAT Project I&T Meeting – Jan 29,2004

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Other Important ItemsOther Important Items

• Vibration Test Fixture– Have SC Bracket Dwg; We are building model– Stress indicates four small interface brackets to NRL shaker will

work• No need for $20K large interface plate

• Environmental Tests @ NRL– Expect MGSE Concept for TVAC and EMI ready for presentation

next week ( detail dwgs ~ 80% complete )– Need feedback from NRL

• NRL needs to define Cold / Hot Plate Heat Exchanger Sizing and plumbing

• Need sizes to determine if Heat Ex’rs can be safely slid into place ( Eric believes they can )

• Single Tower Airplane Test– MGSE on hold until PAP is more mature

• Can be worked if additional designer is available

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SummarySummary

• Need Authorization to Proceed for:– Purchase of long lead items

• GPR frame pieces• GPR to Grid attach bracketry• Support Shaft Materials and Machining• Bearings• Rotation Drive, Flex Coupling & Drive Motor

– Rotation System Weldment– LAT Lift Spreaders

• Z Axis Vertical (analysis in work)• Z Axis Horizontal (analysis in work)

– Proof Test Hardware• Design to begin after GPR ATP