GLAST LAT Project Peer Review, March 24-25, 2003
7E2 1
Gamma-ray Large Gamma-ray Large Area Space Area Space TelescopeTelescope
7E2: EM test plans
GLAST Large Area GLAST Large Area Telescope:Telescope:Tracker Subsystem
Nicola MazziottaUniversity and INFNBari - [email protected]
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 2
OutlineOutlineTest strategiesFirst resultsPanel vib planTray thermal
planTower vib planTower thermal
planEM Matrix planReference LAT Documents:
1. LAT-MD-00408, LAT Instrument Performance Verification Plan2. LAT-SS-00788, LAT Environmental Specification3. LAT-TD-01005, Thermal Test Results on Thick Converter Mock-up
Trays4. LAT-TD-01249, Thermal Test Results for Pre-Engineering Model
Trays5. LAT-PS-01584, LAT Tracker Tray SSD Ladder Panel Assembly
Procedure6. LAT-TD-01004, EM Tray Vibration Test Plan 7. LAT-TD-01037, EM Tray Thermal Test Plan
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 3
Tray assembly&test sequenceTray assembly&test sequence
Tray factory (panels)
Vibration test
Ladder factory
Tray assembly: ladders and MCMs on trays
Thermal cycles
Stacked cosmic rays*
Electrical test
Fast electrical test*
Tower assembly* Live trays
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 4
Tray vib levelsTray vib levels
Frequency (Hz)
ASD QualLevel
(g2/Hz)
ASD AcceptLevel
(g2/Hz)
ASD LaunchLevel(g2/Hz)
20 0.026 0.013 0.0065
20-50 +6 dB/oct +6 dB/oct +6 dB/oct
50-800 0.16 0.08 0.04
800-2000 -6 dB/oct -6 dB/oct -6 dB/oct
2000 0.026 0.013 0.0065
Overall 14.0 grms 10.0 grms 7 grms
Duration 2 min 1 min 1 min
Random vibration
Frequency
(Hz)
ASD WN Level(g2/
Hz)
Overall
grms
Duration
(min)
20 ÷ 2000 10-4 0.45 1
White NoiseFrequency
range20 2000 Hz
Sweep rate 2 oct/min
Target Amplitude
0.5 g0-pk
Sine sweep
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 5
Tray vib set upTray vib set up
Accelerometers position:
•Control: two mono-axial accelerometers positioned on two of the four L-shaped block TP1&TP2
•Fixture: three mono axial accelerometers placed on a corner on one of the four L-shaped block TP6
•Tray: one three-axial accelerometer in the middle TP5
Centrotecnica set up:
- 1 LDS V864LT shake table
- 2 fixtures
- 9 read out channels
- 4 trays/day test rate capability
W side on the top
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 6
Tray vib sequence thrust Tray vib sequence thrust axisaxis
Step Description Test Level
1 Fixture, tray and accelerometers
mounting
2 Fixture calibration and tray resonance
searchSine sweep 0.5 g 0-pk
3 Pre-random vibration White noise 0.45 grms
4 Random vibration Random vibration
Launch
5 Post/Pre-random vibration
White noise 0.45 grms
6 Random vibration Random vibration
Acceptance
7 Post/Pre-random vibration
White noise 0.45 grms
8 Random vibration Random vibration
Qualification
9 Post-random vibration White noise 0.45 grms
10 Normal mode check Sine sweep 0.5 g 0-pk
11 Dismounting
12 Test completion
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 7
First results – TG07 (1)First results – TG07 (1)
Sine sweep before/after random Random vibration + White noise
Resonance search:
0= 815 Hz, Q 51
Resonance check:
0= 809 Hz, Q 49
Z accelerometer response
X accelerometer response
Y accelerometer response
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 8
Light
≈ 1000Hz
≈ 800Hz Heavy tray
Mid tray
Last Vib Runs (Mar, 17-19) (1)Last Vib Runs (Mar, 17-19) (1)
≈ 660Hz
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 9
Last Vib Runs (Mar, 17-19) (2)Last Vib Runs (Mar, 17-19) (2)
“Watch-dog”Input-notched: 13.6 grms
Output-notched: 59.6 grms
Applied notching on qual ASD: output ≤ 16 g2/Hz ( Q=10) “Watch-dog”
Heavy tray (TS05) Q=100 @ 660Hz Output-expected: 140.4 grms
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 10
EM Vib Runs Summary (16 trays)EM Vib Runs Summary (16 trays)
All trays first mode › 500 Hz
No relevant changes in the resonance frequency after the
random
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 11
Thermal tests on pre-EM trays: set-Thermal tests on pre-EM trays: set-upup
Wheatstone bridge
configuration(Labview)
Si Strain gauge
Reference Strain gauge on quartz
1 m3
Procedures: LAT-TD-1037; Pre-EM Results: LAT-TD-1249
Service box
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 12
Thermal tests on pre-EM trays: some Thermal tests on pre-EM trays: some resultsresults
Silicon temperature delay 45 min
Stability @ plateau: dT/dt < 3°C/hrTchamber
Tsilicon
plateau 5 hr
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 13
Tray thermal levelsTray thermal levelsAcceptance Qualification/Survival
Temperature Range -20°C 35°C -30°C 50°C
# of cycles 4 4
Temperature rate 20°C/hr 20°C/hr
Pressure 1 atm T-C‹ 10-5 Torr T-V
1 atm T-C‹ 10-5 Torr T-V
Duration @ T extreme
5 hr 5 hr
Total Duration 62 + 2 hr 72 + 2 hr
T-C: Thermal cycle (dummy trays)
T-V: Thermal vacuum (live tray)
On orbit temperature range -15°C 30°C
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 14
Tray thermal Tray thermal sequencesequence
Step Description Level
0 Strain gauges and thermocouple set
up
1 Chamber set up
2 Strain gauges calibration
3 Thermal cycles Qualification
4 Dismounting
5 Test completion
The EM dummy trays will be tested at ambient pressure into the service
boxes
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 15
Tower vib levelsTower vib levels
Frequency(Hz)
ASD Acceptance
Level (g2/Hz)
ASD Qualification Level (g2/Hz)
20 0.01 0.02
20-50 +5.9 dB/oct +5.9 dB/oct
50-800 0.06 0.12
800-2000 -5.9 dB/oct -5.9 dB/oct
2000 0.01 0.02
Overall 8.7 grms 12.3 grms
Duration 1 min/axis 2 min/axis
Low frequency sine sweep
Frequencyrange
20 2000 Hz
Sweep rate 2 oct/min
Target Amplitude
0.5 g0-pk
High frequency sine sweep
Frequency
(Hz)
ASD WN Level(g2/
Hz)
Overall
grms
Duration
(min)
20 ÷ 2000 10-4 0.45 1
White Noise
Random vibration
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 16
Tower vib set upTower vib set up
Accelerometers set up (TBR):1. 3 axial on the shaker table (control accelerometer) 2. 3 axial on the center of the bottom tray lower surface 3. 3 axial on the center of the top tray upper surface 4. 3 axial accelerometer +X sidewall center of the thermal
boss tray number 12;5. 3 axial accelerometer +Y sidewall near the center of the
tray number 10;6. 3 axial accelerometer +Y sidewall center of the thermal
boss of the tray number 1;7. 3 axial accelerometer +Y sidewall center of the thermal
boss of the tray number 19;8. 3 axial accelerometer -X sidewall center of the thermal
boss of the tray number 10;9. 3 axial accelerometer -Y sidewall near the center of the
tray number 10, on the center plane;
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 17
Tower vib sequence X,Y,Z Tower vib sequence X,Y,Z axisaxis
For each axisStep Description Test Level
1 Fixture, tower and accelerometers mounting
2 Fixture calibration High frequency sine sweep
0.5 g 0-pk
3 Normal mode search High frequency sine sweep
0.5 g0-pk
4 Pre-random vibration White noise 0.45 grms
5 Random vibration Random vibration -6 dB Qual
6 Post/Pre-random vibration White noise 0.45 grms
7 Random vibration Random vibration -3 dB Qual
8 Post/Pre-random vibration White noise 0.45 grms
9 Random vibration Random vibration 0 dB Qual
10 Post-random vibration White noise 0.45 grms
11 Normal mode check High frequency sine sweep
0.5 g0-pk
12 Low frequency test Low frequency sine sweep
Qual
13 Dismounting
14 Test completion
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 18
Tower thermal levelsTower thermal levels
Thermal-Vacuum cycling/Qual-Surv level
Ranges -30°C 50°C
# of cycles 8 (12)
Temp. rate 20°C/hr
Pressure 10-5 Torr
Duration @ extreme 12 hr
Total Duration 256 (384) hr + stabilization
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 19
Tower thermal set upTower thermal set up
Additional thermocouples (TBR):1.+Y sidewall center of the thermal boss of the tray number 1;2.+X sidewall center of the of the tray number 1, on the center plane;
3.+Y sidewall center of the thermal boss of the tray number 19;4.+X sidewall center of the of the tray number 19, on the center plane;
5.-X sidewall center of the thermal boss of the tray number 10;6.-Y sidewall near the center of the tray number 10, on the center plane
The tower has a large number of thermocouples in the read out cables that can be acquired by using the TKR DAQ system.
The temperature control point for the cold part of the cycle will be the coldest thermocouple, while
the control point for the hot part of the cycle will be the hottest one.
Tower covered with a thermal blanket during T-V cycles.
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 20
Tower thermal Tower thermal sequencesequence
Step Description Level
0 (Strain gauges and) Thermocouple set up
1 Chamber set up
2 (Strain gauges calibration)
3 Thermal vacuum cycles Qualification/Survival
4 Dismounting
5 Test completion
GLAST LAT Project Peer Review, March 24-25, 2003
7E2 21
EM matrixEM matrix
Item
Qu
an
tity
Qu
an
tity to
test
Hig
h fre
q s
ine
Sw
eep
20-2
000 H
z
Ran
dom
Vib
e
Wh
ite n
ois
e
Low
freq
sin
e
Sw
eep
5-5
0 H
z
Fu
nctio
nal
Th
erm
al C
ycle
Th
erm
al V
acu
um
Test s
ite
Panels
24 24 QualZ axis
QualZ
axis
Centrotecnica (vib)
Live Trays
5 1 QualZ axis
QualZ
axis
Qual Centrotecnica (vib)
Alenia (thermal-vac)
Dummy Trays
19 5 vib19 ther
QualZ axis
Qual Z
axis
Qual Centrotecnica (vib)
INFN Perugia (in Terni) (thermal)
Tower 1 1 QualX,Y,Z
QualX,Y,Z
Qual Alenia