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Gamma-ray Large Area Space Telescope. TEM/TPS TRR. GLAST Large Area Telescope: Presented by G. Haller SLAC haller@slac.stanford.edu (650) 926-4257. Contents. Introduction Overview Significant Changes since CDR Objectives Status Requirements/Verification EGSE and Test-Procedures
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Gamma-ray Large Area Space Telescope TEM/TPS TRR GLAST Large Area Telescope: Presented by G. Haller SLAC haller@slac.stanford.edu (650) 926-4257
Contents • Introduction • Overview • Significant Changes since CDR • Objectives • Status • Requirements/Verification • EGSE and Test-Procedures • Verification Test Plan and Flow • At Assembly Vendor • Test-plan and Flow • Facility • Man-Power • Quality Assurance • Vibration • At SLAC • Test-plan and Flow • Thermal Vacuum Test • Mass Property • EMI/EMC (at sub-contractor) • Man-Power • Quality Assurance • Equipment Calibration/Safety • Risk Assessment • Schedule • Status of Procedures • Issues and Concerns
LAT Electronics TKR Front-End Electronics (MCM) ACD Front-End Electronics (FREE) TKR CAL Front-End Electronics (AFEE) 16 Tower Electronics Modules & Tower Power Supplies CAL Global-Trigger/ACD-EM/Signal-Distribution Unit* 3 Event-Processor Units (EPU) (2 + 1 spare) • Event processing CPU • LAT Communication Board • SIB Spacecraft Interface Units (SIU)* • Storage Interface Board (SIB): Spacecraft interface, control & telemetry • LAT control CPU • LAT Communication Board (LCB): LAT command and data interface Power-Distribution Unit (PDU)* • Spacecraft interface, power • LAT power distribution • LAT health monitoring * Primary & Secondary Units shown in one chassis
TEM/TPS Mounted to CAL TKR not shown LAT GRID with 16 CAL/TEM/TPS Modules CAL TEM TPS
Tower Electronics Module EM Tower Electronics Module (TEM) before coating/staking • Main DAQ module, one on each tower • Controls and reads out data from TKR MCM and CAL AFEE front-end electronics • Zero-suppresses CAL event data • Buffers events in cable ASIC FIFO’s • Assembles CAL and TKR event fragments to tower event • Transmits data to GASU • Contains monitoring and low-rate science circuits • LVDS interface to front-end electronics and GASU TEM Assembly
Tower Power Supply EM Tower Power Supply (TPS) before coating/staking • Tower Power Supply module, one on each tower • Input 28V • Generates low-noise voltages for • TKR (2.65V analog, 2.65V Digital) • CAL (3.3V analog, 3.3V digital) • TEM (3.3V and 2.5V digital) • TKR Bias (20V-140V programmable) • CAL (20V to 90V programmable) • Temperature sensors TPS Assembly
TEM/TPS Assembly After TEM and TPS are tested individually, the two modules are mated and the TEM/TPS package is tested TPS TEM Shown upside-down TPS TEM
Changes since TEM CDR and Power-Supply Delta CDR • Power Supply Review from 9-22-03 • SLAC GLAST web-site -> Electronics & DAQ -> Reviews • TEM • Modification of FPGA code • To fix a couple of bugs • To change flow-control slightly to optimize dataflow throughout system • Code was reviewed by GSFC reviewer (Dr Rod) • Some resistor/capacitor values have changed to optimize monitoring ranges • Details of monitoring circuit have changed and a sub-set of current monitoring functions were eliminated • TPS • Resistor/capacitor changes to optimize circuit performance over temperature • Changes in poly-switch values to protect better over temperature (instead of RXE185, split the load into two paths with a RXE110 each), increased the current sensing resistor from a 1W to a 3W resistor. • Changed resistor values to • Modify TKR 2.5V to 2.65V • Decrease maximum CAL Bias from 120V to 90V • Changed Zener diodes at Bias output voltage for new max values • Changed resistor values to optimize in-rush current level • Worst Case Analysis updated to incorporate changes • Thermal Analysis from CDR/Delta-CDR remained since changes don’t impact thermal performance
Objectives • Demonstrate that hardware, software, procedures, and support equipment are prepared to support system environmental test • Demonstrate that planned and completed testing meets performance and interface requirements • Identify and understand all the risks and limitations • TRR is not intended to • Review TEM/TPS design • Review flight readiness • Buy-off hardware or software • RFA’s should only be of sufficient concern to stop test • Prior to start of an given test, any applicable TRR RFAs must be closed
Test Entrance / Exit Criteria • Entrance • All required paperwork released and in place • Procedures, drawings, etc • Test configuration verified and approved • Essential personnel in place • Pre-test TEM/TPS functional successfully passed • Exit • As-run procedures completed • Correct and accurate application of test environment • Test data acquired and archived • No damage to TPS/TEM • TEM/TPS performance within specification limits • Post-test TEM/TPS functional successful
Status • 3 TEM/TPS • Qualification unit, Tower A, and Tower B units • Assembled, • Functional tested • Ready for environmental test • Assembly of balance of 19 TEM and TPS authorized to proceed, but not started yet • All parts at assembler
Tests To-Date • TEM and TPS engineering modules were extensively tested • As EGSE in DAQ/CAL/TKR/I&T • >50 test-stands were tested with SLAC TPS and TEM Test Procedure • TEM and TPS were used to test functionality and performance of TKR and CAL sub-system electronics • Met requirements by sub-system • CAL performed vibration tests on coated/staked TEM/TPS to CAL levels, passed (exceptions were first modules in-house staked) • Additional TEM/TPS tests • Informal thermal-vacuum test -40C to 55C, passed CPT • Vibration tests of staked TEM/TPS passed DAQ qual levels • On test-bed • 16 TEM/TPS connected to EM PDU and GASU and to Front-End Simulator modules generating trigger and event-data • Run up to 10 KHz data-rates
Tests To-date (con’t) • On fully-instrumented tower • 36 TKR MCM’s • 4 CAL AFEE’s • Ran tests and passed • Test results for TEM/TPS performance tests posted for the EGSE TEM/TPS • E.g. TEM/TPS delivered to CAL: • http://www-glast.slac.stanford.edu/Elec_DAQ/EGSE/CAl-AFEE/cal.htm • IO tested to sub-system ICD‘s • Configuration and data-taking tested • Monitoring functions/performance tested • Tested over • Frequency (16Mhz to 22 MHz, 20 MHz nominal) • Temperature (-40C to 55C) • TEM supply range (3.3V +/- 10%, 2.5V +/-10%) • One flight PCB TEM/TPS was loaded at SLAC with mostly parts from flight lots, including flight-lot ACTEL FPGA‘s • Passed tests from -40C to 55C over voltage and frequency • Three TEM and TPS flight modules assembled at flight-assembly vendor individually tested with CPT procedures, over temperature, passed tests
Requirements • LAT-SS-00019 Specifications, Level 3 T&DF Subsystem Specification • LAT-SS-00284 Specifications, Level 4 Trigger • LAT-SS-00285 Specifications, Level 4 Dataflow • LAT-SS-00136 Specifications, Level 3 Power Supply System • LAT-SS-00183 Specifications, Level 4 Power Supply System • LAT-SS-05522 Specifications, Level 5 TEM Specification • LAT-SS-01281 Specifications, Level 5 TPS ICD & Specification • LAT-SS-05533 Specifications, Level 5 TEM/TPS Specification
Derived Requirements • LAT-SS-05533 TEM/TPS lists 132 requirements for TEM/TPS package (most are from TEM LAT-SS-05522 (108) with extensions (24) to include TPS requirements for the TEM/TPS package) • Verification Matrix gives approach to verify each requirement • LAT-TD-05536 • Lists verification method used • Assembly level at which requirement is verified • All TEM requirements at TEM assembly level (LAT-SS-05522) • ALL TPS requirements at TPS assembly level (LAT-SS-01281) • TEM/TPS package requirements at TEM/TPS assembly level (LAT-SS-05533)
System Performance • Level 3 and level 4 DAQ and TRG and power-system requirements are met with a combination of DAQ modules (TEM/TPS, GASU, SIU, PDU, etc), since the DAQ and trigger and power system is comprised of several sub-system module types • Level 5 TEM/TPS requirements which are verified are derived from Level 3 and Level 4 DAQ and Trigger and Power system specifications (as noted in the L5 requirements doc) • Level 5 requirement doc includes derived requirement addressing • Functionality/performance • Power • Mass/C.G. • EMI/EMC • Environmental incl temperature and vibration
Verification Status • Engineering Module TEM/TPS • EM completed full environmental/functional test program with exception of EMI/EMC, mass, and C.G. • Demonstrated compliance with specifications
EGSE and Test-Procedures • EGSE for Functional/Performance Tests • Test-Stand documented in LAT-DS-04085 • TEM (at TEM module level) • TEM Stray-Voltage-Test Procedure LAT-TD-04097 • TEM Electrical Interface Continuity and Isolation Test procedure LAT-TD-03831 • TEM Test-Procedure LPT LAT-TD-03415 • TPS (at TPS module level) • TPS Stray-Voltage-Test Procedure LAT-TD-04098 • TPS Electrical Interface Continuity and Isolation Test procedure LAT-TD-04099 • TPS Test-Procedure LPT LAT-TD-01652 • TEM/TPS (at combined unit level) • TEM/TPS Performance Test Procedure LAT-TD-01485
EGSE Test-Configuration • LAT-DS-04085
Verification Level – Module Detail • Breakout of verification at TEM/TPS Module Level • Tests to be conducted after successful TRR • At assembly vendor • Functional test • Vibration • Functional test • Thermal cycle • Functional test • Pre-ship review • At SLAC • Incoming functional test • Mass properties • Thermal vacuum (in-situ testing) • EMI/EMC • Functional test • Review • Deliver to I&T • DAQ (out-going) / I&T (incoming) test combined • In the following slides first the work/tests at the assembly vendor is defined, then the work/tests at SLAC
At Assembly Vendor • Test-Stand • Supplied by SLAC • Operated by SLAC engineers • Vibration facility at General Technology • Vibration test-procedure • http://www-glast.slac.stanford.edu/Elec_DAQ/Reviews/TEM-TRR/SK-282-SLAC-ESS-Procedure-11-03-04.pdf • Also includes • Thermal test procedures • Environmental chamber (thermal/vibration) description • SLAC engineers present for vibration tests • Work at assembly vendor specified in SOW • LAT-PS-02615
Process & Test Flow-GTC (Assembly Vendor) • See also in more detail in • http://www-glast.slac.stanford.edu/Elec_DAQ/Reviews/TEM-TRR/SK-282-SLAC-ESS-Procedure-11-03-04.pdf Assemble TEM/TPS Stake HW Functional Test Vibration Test Source inspection &EIDP review Functional test Thermal test Final functional test Pack & ship to SLAC
GTC Environmental Test Requirements Figure 1. Vibration Levels, Duration, and Spectra
Manpower & Quality Assurance at Assembly Vendor • Man-Power • Thermal and vibration test man-power provided by assembler • Test man-power supplied by SLAC • TEM: L. Sapozhnikov • TPS: D. Nelson • Test Support: J. Ludvik • Quality assurance: see below • Quality Assurance • Assembly QA by vendor as required by SOW • On-site, full-time LAT QA presence (P. Lujan) • Required changes to documentation at GTC is immediately documented on an NCMR and forwarded to SLAC for disposition • All outstanding changes to documents are incorporated and a new revision released into LAT DOCs prior to final inspection at each manufacturing/test level (CCA, Module, Top Assembly)
At SLAC • After TEM/TPS module has been shipped from assembly vendor to SLAC: • Test-Stand • Supplied by SLAC, operated by SLAC engineers • Work flow • Functional Test • Mass Property • Plus C.G. measurement • Thermal Vacuum (in-situ testing) • Functional Test • Ship to EMI/EMC vendor • EMI/EMC test • Ship back to SLAC • Final functional test • Review
Mass Property • Mass properties checked at SLAC • Procedure in progress (done at SLAC Metrology) • Measured on EM (ref LAT-TD-00564) • TEM 2.710 kg • TPS 4.340 kg • TEM/TPS Total 7,050 kg • Allocation 12% above = 7,896 kg • C.G. to be measured for the qualification unit
Thermal Vacuum Test • Thermal Vacuum facility in Building 33 at SLAC • Thermal Vacuum Chamber Operating Procedure LAT-TD-02541 (draft in review) • TEM/TPS Thermal Vacuum Test-Procedure LAT-TD-03631 ( draft in review) • Chamber was relocated to Building 33 from Central Lab • Needs earth-quake securing, in progress (by 1/10) • Needs recalibration (by 1/15)
Qual and Flight Acceptance Thermal Vacuum Test • See TEM/TPS Thermal Vacuum Test-Procedure LAT-TD-03631 At < 10-5 Torr
Manpower & Quality Assurance at SLAC • Man-Power • Thermal Vacuum test (R. Williams, J. Ludvik) • Test man-power supplied by SLAC • TEM/TPS: L. Sapozhnikov, D. Nelson, J. Ludvik • Quality Assurance • LAT QA already present at SLAC • Required changes to documentation is immediately documented on an NCMR
EMI/EMC Test • Qualification Test (Conductive & Radiative) • Sub-contracted to CK Labs • Statement of Work: LAT-PS- 04568 • CE102, CECN, CS102, CSCM, CS06, RE101, RE102, RS101, RS103 • Detailed EMI/EMC procedure deliverable by vendor (in work) • Required to be reviewed/released prior to tests • SLAC engineers present at vendor for tests • Vendor supplies test-report • LAT QA at SLAC present for tests • Flight Acceptance Test (Conductive) • Performed at SLAC • Procedure in work • Required to be reviewed/released prior to tests • CE102, CS102 • SLAC supplies test-report • LAT QA at SLAC present for tests
Problem Failure Report/ Configuration Management • Problem Failure Reporting • Via standard SLAC LAT Non-Conformance Reporting (NCR) System • NCR is entered • Reviewed/accepted/resolved • LAT engineering • LAT QC • Already exercised during past TEM/TPS assembly • Configuration Management • Via standard LATDOC system
Planned Tests • Function/Performance Tests (LAT-TD-01485) • Verifies all requirements in LAT-SS-05533 except below • Thermal Vacuum Tests • Verifies performance/function over temperature • Mass/C.G. • Verifies/measures mass and C.G. • Vibrations test • Verifies vibration performance requirements • EMI/EMC • Verifies EMI/EMC performance
Equipment Calibration • Electrical Functional Test Equipment • EGSE Test-Stand was certified by SLAC (will be posted on LAT EGSE web-site shortly) • EMI/EMC Test Equipment • Quantitative measurement equipment (sensors, antennas, etc) calibrated to NIST standards • Calibration performed annually • All item are (will be) within calibration at time of testing • Vibration Test Equipment • Accelerometers calibrated against a standard accelerometer traceable to NIST • Signal conditioners calibrated annually • TVAC Equipment • Thermocouples calibrated against standard temperature; calibrated prior to test • Thermocouple reader calibrated very 2 years
Sub-System Safety • EGSE • Safe-to-mate • Configuration control • Calibration verification • Functionality verification with “golden” TEM/TPS prior to test with flight hardware • MGSE • No custom MGSE • Environment • Temperature controlled in all test-facilities • Cleanliness actively controlled in clean-room; hardware bagged and purged when required • Training • ESD training completed • Clean room training completed
Risk Assessment • GTCC/GCCC TEM ASICs qualification program not completed at GSFC • No issue to-date • Test completion end of February • ACTEL FPGA’s • TEM’s use relatively new UMC fabrication-line space-qualified FPGA’s, no flight heritage • ESD sensitivity of ASIC’s higher than expected (200V, class 0) • Mate-demate and safe-to-mate are of concern when connecting/disconnecting TEM to front-end test (simulator) board. Keep cables as short as possible, apply handling taught in ESD-training, use de-ionizers • Schedule • Pressure to deliver flight hardware could force less than complete characterization and analysis of modules, could result in replicating a problem in follow-on modules • Performance • None known
Test-Schedule • Depending on assembly vendor, estimate as follows • 1/10/05: functional test of qual/TwrA/TwrB • 1/11-12/05: vibration test of qual/TwrA/TwrB • 1/13/05: functional test of qual/TwrA/TwrB • 1/14-15/05: TC of qual/TwrA/TwrB • 1/16/05: functional test of qual/TwrA/TwrB • 1/17-21: review/shipping • 1/24/05: functional test of qual/TwrA/TwrB • 1/25/05: mass, c.g. property test of qual/TwrA/TwrB • 1/26/05: TV start of TwrA, end Feb 2 • 2/3/05: EMI/EMC of TwrA, end 2/5/05 • 2/7/05: TV start of TwrB, end Feb 14 • 2/15/05: EMI/EMC of TwrA, end 2/16/05 • 2/15/05: TV start of Qual, end Feb 22 • 2/22/05: EMI/EMC of Qual, end 3/8/05
Status of Main Test Procedures • TEM/TPS Performance Test Procedure LAT-TD-01485: released • Vibration & thermal cycle procedure • GT procedure SK-282-SLAC: approved • EMI/EMC • Qual • CKC Lab procedure: will be started 2nd week of January • Flight • Working together with TKR to get procedure finished by 3rd week of January (procedures are similar) • Thermal Vaccum • LAT-TD-03631, in draft form • All procedures must be released before respective test
Issue & Concerns • EMI tests • Concern passing qualification tests • Schedule • Tight • Qualification and Flight acceptance tests of flight TEM/TPS are performed with front-end simulators, not with actual CAL or TKR electronics • In the planning phase: • Taking qualification module after baseline environmental testing is completed • Connect it to CAL AFEE / TKR MCM electronics • Test over temperature (no vacuum required) • Need documentation • Possible for every flight modules: schedule issues