W/NSA...V2 "A" latch random input auto spectral density 48 68. V2 c.g. response auto spectral...
Transcript of W/NSA...V2 "A" latch random input auto spectral density 48 68. V2 c.g. response auto spectral...
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NASATechnicalMemorandum
NASA TM- 86454
W/NSA
RADIAL SI LATCHES VIBRATION TEST DATA REVIEW
By Phillip M. Harrison and James Lee Smith
Systems Dynamics Laboratory
July 1984
National Aeronautics andSpace Administration
George C. Marshall Space Flight Center
MSFC - Form 3190 (Rev. May 1983)
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TECHNICAL REPORT STANDARD TITLE PAGE1. REPORT NO.
NASA TM-864542. GOVERNMENT ACCESSION NO. 3. RECIPIENT'S CATALOG NO.
4. TITLE AND SUBTITLE
Radial SI Latches Vibration Test Data Review
5. REPORT DATE
July 19846. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Philip M. Harrison and James Lee Smith8. PERFORMING ORGANIZATION REPORT ff
9. PERFORMING ORGANIZATION NAME AND ADDRESS
George C. Marshall Space Flight CenterMarshall Space Flight Center, Alabama 35812
10. WORK UNIT NO.
1 1. CONTRACT OR GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
13. TYPE OF REPORT & PERIOD COVERED
Technical MemorandumNational Aeronautics and Space AdministrationWashington, B.C. 20546 14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
Prepared by Systems Dynamics Laboratory, Science and Engineering
16. ABSTRACT
Dynamic testing of the Space Telescope Scientific Instrument Radial Latcheswas performed as specified by the designated test criteria. No structural failureswere observed during the test. The alignment stability of the instrument simulatorwas within required tolerances after testing. Particulates were discovered aroundthe latch bases, after testing, due to wearing at the "B" and "C" latch interfacesurfaces. This report covers criteria derivation, testing, and test results.
17. KEf WORDS
Space Telescope Scientific InstrumentsRadial Latches
Vehicle TransientsRandom Vibration
18. DISTRIBUTION STATEMENT
Unclassified-Unlimited
19. SECURITY CLASSIF. (of thU report!
Unclassified20. SECURITY CLASSIF. (of this page)
Unclassified21. NO. OF PAGES
68
22. PRICE
NTIS
MSFC - Form 3392 (May 1969)For sale by National Technical Information Service, Springfield. Virginia 22151
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TABLE OF CONTENTS
Page
I. INTRODUCTION 1
II. DESCRIPTION OF TEST ITEMS 1
III. TEST CRITERIA AND DEVELOPMENT 1
A. Sinusoidal Diagnostic Survey 21. 0.1 G Level 22. 0.25 G Level 2
B. Vehicle Transient 21. Half Level 32. Full Level 3
C. Random Vibration 31. Half Level 32. Full Level 3
IV. TEST APPARATUS 4
V. TEST PROCEDURE 4
VI. DATA AND EVALUATION 4
A. Sinusoidal Diagnostic Survey 5B. Vehicle Transient 5C. Random Vibration 5
VII. SUMMARY AND CONCLUSIONS 6
A. Summary 6B. Conclusions 6
APPENDIX A - DATA AND ILLUSTRATIONS 7
APPENDIX B - DATA ANALYSIS PLOTS 33
APPENDIX C - ANALYSIS EQUATIONS 59
ill
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LIST OF ILLUSTRATIONS
Figure Title Page
1. Test configuration 8
1.1. Latch A, FPS half 9
1.2. Latch A, SI half 10
1.3. Latch B 11
1.4. Latch C, SI half 12
1.5. Latch C, FPS half , 12
2. Vehicle transients 13
3. Vehicle transients 13
4. VI axis transient criteria 14
5. V2 axis transient criteria 14
6. V2 axis transient criteria 15
7. V3 axis transient criteria 15
8. V3 axis transient criteria 16
9. Random vibration criteria - 145 dB basis 16
10. Space shuttle cargo bay acoustic criteria 17
11. Random vibration criteria - 139 dB basis 17
12. Random vibration criteria 18
13. Test configuration 18
14. VI axis sine sweep control average 19
15. VI axis e.g. pre- and post-test data 19
16. VI axis transient control average 20
17. VI axis e.g. transient response 20
18. VI axis random control average 21
19. VI axis e.g. random response 21
20. V2 axis sine sweep control average 22
IV
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LIST OF ILLUSTRATIONS (Continued)
Figure Title Page
21. V2 axis e.g. pre- and post-test data 22
22. V2 axis transient control average - test 1 23
23. V2 axis e.g. transient response 23
24. V2 axis transient control average - test 2 24
25. V2 axis e.g. transient response 24
26. V2 axis random control average 25
27. V2 axis e.g. random response 25
28. V3 axis sine sweep control average 26
29. V3 axis e.g. pre- and post-test data 26
30. V3 axis transient control average - test 1 27
31. V3 axis e.g. transient response 27
32. V3 axis transient control average - test 2 28
33. V3 axis e.g. transient response 28
34. V3 axis random control average 29
35. V3 axis random response 29
36. "A" latch random input 30
37. "B" latch random input 30
38. "C" latch random input 31
39. VI "A" latch random auto spectral density 34
40. VI inside "A" latch random auto spectral density 34
41. "A" latch transfer function 35
42. "A" latch coherence 35
43. VI "B" latch random auto spectral density 36
44. VI inside "B" latch random auto spectral density 36
45. "B" latch transfer function 37
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LIST OF ILLUSTRATIONS (Continued)
Figure Title Page
46. "B" latch coherence 37
47. VI "C" latch random auto spectral density 38
48. VI inside "C" latch random auto spectral density 38
49. "C" latch transfer function 39
50. "C" latch coherence 39
51. VI "A" latch random input auto spectral density 40
52. VI e.g. response auto spectral density 40
53. VI "A" latch input versus e.g. transfer function 41
54. VI input versus e.g. coherence 41
55. V2 "A" latch random auto spectral density 42
56. V2 "A" latch inside random auto spectral density 42
57. V2 "A" latch transfer function 43
58. V2 "A" latch coherence 43
59. V2 "B" latch random auto spectral density 44
60. V2 "B" latch inside random auto spectral density 44
61. V2 "B" latch transfer function 45
62. V2 "B" latch coherence 45
63. V2 "C" latch random auto spectral density 46
64. V2 "C" latch inside random auto spectral density 46
65. V2 "C" latch transfer function 47
66. V2 "C" latch coherence 47
67. V2 "A" latch random input auto spectral density 48
68. V2 c.g. response auto spectral density 48
69. V2 input versus e.g. transfer function 49
70. V2 input versus e.g. coherence 49
vi
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LIST OF ILLUSTRATIONS (Concluded)
Figure Title Page
71. V3 "A" latch random auto spectral density 50
72. V3 "A" latch inside random auto spectral density 50
73. V3 "A" latch transfer function 51
74. V3 "A" latch coherence 51
75. V3 "B" latch random auto spectral density 52
76. V3 "B" latch inside random auto spectral density 52
77. V3 "B" latch transfer function 53
78. V3 "B" latch coherence 53
79. V3 "C" latch random auto spectral density 54
80. V3 "C" latch inside random auto spectral density 54
81. V3 "C" latch transfer function 55
82. V3 "C" latch coherence 55
83. V3 "A" latch random input auto spectral density 56
84. V3 c.g. response auto spectral density 56
85. V3 input versus e.g. transfer function 57
86. V3 input versus e.g. coherence 57
Vll
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TECHNICAL MEMORANDUM
RADIAL SI LATCHES VIBRATION TEST DATA REVIEW
I. INTRODUCTION
A dynamic test program of the Space Telescope Scientific Instruments Latcheswas requested by the Marshall Space Flight Center Latch Design Audit Team. Thetest program included random vibration, transient shock, and modal testing on thelatches for the axial and radial scientific instruments. The test program was requiredfor flight qualification of the SI latches.
This report describes the criteria development, types of testing, purposes fortesting, test apparatus, test procedure, and results and analysis of test data for theradial SI latches.
II. DESCRIPTION OF TEST ITEMS
Latch "A" (Figs. 1, 1.1, and 1.2) consists of two parallel interfaced plates.A threaded ball is permanently bound within a socket between the two plates. Inlatching, a threaded rod is secured to the ball. Latch "A" will accept loads in allthree directions.
Latches "B" and "C" are pin-and-socket configurations. Each latch consists oftwo halves that interface perpendicularly. Latch "B" (Figs. 1 and 1.3) accepts loadin the VI direction only. Latch "C" (Figs. 1, 1.4, and 1.5) accepts loads in the VIand V2 directions.
To securely latch a radial scientific instrument to the Space Telescope, the pinsof latches "B" and "C" are pulled into their receptors as the threaded rod isscrewed into latch "A".
III. TEST CRITERIA AND DEVELOPMENT
The test criteria for the series of dynamic tests to be performed on the radialSI latches is designed to evaluate the dynamic response of the test article and toexpose the test article to the simulated flight dynamic environments. The test criteriawill be notched if necessary to avoid exceeding the following maximum design loads:
Axis Peak G's
VI 6.23V2 2.33V3 3.11
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A. Sinusoidal Diagnostic Survey Test Criteria
Sinusoidal test criteria levels were chosen at levels and sweep rates to precludeexceedance of the above designated maximum design loads. Natural frequencies anddamping of the test article were predicted and the test level was determined suchthat the loading of the test article would not be significant during the sine sweeptests.
1. 0.1 G Level
A 0.1 g sine sweep from 5 to 2000 Hz at 3 octaves/min was used to identifyfundamental frequencies, to determine the damping factor, and to determine ifnotching was required in the 0.25 g sine sweep. This test also allowed checking ofcontrol and center-of-gravity (e.g.) accelerometers before beginning the 0.25 g sinesweep. This was the initial vibration test in each axis. A 0.1 g sine sweep wasselected at random for convenience because of its low level. A 0.05 g or 0.15 g testcould have been used.
2. 0.25 G Level
A 0.25 g level test was chosen because it produced the desired response level.The 0.25 g sine sweep was conducted at 3 octaves/min from 5 to 2000 Hz before andafter the random and the transient vibration tests. The vibration "signatures" fromthe pre- and post-test sine sweeps were analyzed to determine if any changesoccurred in the latches due to random or transient testing. Changes in the "signa-tures" usually indicate some structural change in the test specimen (broken or over-stressed members, loose bolts and nuts, binding, or work interfaces).
B. Vehicle Transient Criteria
Shock spectra and time histories were calculated by space shuttle coupled loadscomputer simulation analysis. Five liftoff and five landing cases were selected as"worst" cases. Forcing functions used in the computer model included space shuttlemain engine (SSME) thrust, solid rocket booster (SRB) thrust, SRB internal pressure,SRB ignition overpressure, SSME side loads, steady state wind and gusts, groundreactions at the base of the SRB's, and in landing: angle of attack, cross winds,horizontal velocity, and sink speeds. Figures 2 and 3 are examples of the shockspectra and time histories. See NASA memorandum ED22-84-25 for all of the data.
Neither the response time histories nor the shock response spectra could bereproduced in the test laboratory due to test equipment limitations. Consequently,a fast sinusoidal sweep in the appropriate frequency range was chosen to simulate thetransient environment. Amplitudes for the test were obtained from the peak valuesof the calculated response time histories. Frequency ranges were determined fromthe shock response spectra of the transient time histories. Sinusoidal sweep rateswere adjusted to produce a factor of 3 on the number of peaks (between the maximumamplitude and six decibels below maximum amplitude) from the transient time histories.The resulting test criteria are presented in Figures 4 through 8.
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1. Half Level
A half-level transient test was conducted as a calibration run. Data from thistest were evaluated to determine if the desired response amplitude and number ofcycles would be achieved during the full-level transients. Adjustments were made,if necessary, to the amplitude and sweep rate of the full-level transient test criteria,to achieve the desired response.
2. Full Level
A full-level transient test was then conducted at levels and sweep rates formu-lated from the half-level transient test data. The purpose of this test is to simulatethe liftoff vehicle transients of actual flight.
C. Random Vibration Criteria
The original predicted cargo bay acoustic criteria for the space shuttle was145 dB. Space Telescope (ST) random criteria were based on measured vibrationdata from the ST-Structural Dynamic Test Vehicle (SDTV) vibroacoustic test. Theresulting random criteria for the scientific instruments were 9.5 grms, as shown inFigure 9.
Based upon the data from the first four shuttle missions, the cargo bay acousticcriteria were revised downward to 139 dB. Figure 10 compares 145 dB and 139 dBacoustic levels. Likewise, the random criteria were scaled downward to 4.6 grms, asshown in Figure 11.
Evaluating STS flight payload data from missions 1 through 9 indicated thatstructure-borne excitation exceeds acoustically induced vibration in the 20 to 200 Hzfrequency range. A third criteria modification was made to include this low frequencyexceedance. Figure 12 illustrates the modified criteria used in the latch test.
1. Half Level
A half-level random test was conducted to verify control system capability, todetermine magnification factor (Q) at the fundamental frequency, to check cross axisresponse, and to determine if notching is required to stay within the maximum designloads.
2. Full Level
A 60-second full-level random test was conducted to qualify the latches for themaximum expected flight random vibration environment. Single mission random vibra-tion test time is based upon the actual time the environment is present times a factorof three (a factor of safety on the quality of the test article); however, a minimumtest time of 1 min is recommended for adequate equalization of the control system andto provide sufficient time for data acquisition. Test time for the SI latches is set bythe 1 min minimum.
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IV. TEST APPARATUS
Figure 1 illustrates the scientific instrument simulator. Attached to the simu-lator are the latches. Also the latches are attached to the test fixture. Figure 1also illustrates the locations of the control and response accelerometers.
Figure 13 illustrates the test fixture and shaker table configurations for thethree axes. In the VI axis only one shaker is used. The latches, simulator and analuminum plate attach directly to the shaker. In the V2 and V3 axes, the followingconfiguration is used: two large granite "team" tables mount onto a concrete floor.A 2-in. thick magnesium plate is mounted upon the team tables. This plate is oillubricated. A 6-in. thick aluminum plate is bolted to the mangesium plate. Thisaluminum plate is machined out and foam filled. Another 2-in. thick aluminum platebolts above. The latches then bolt to this plate. Four shakers attach to the 6-in.aluminum plate at the four corners as indicated in the figure. A computer systemcontrols and monitors the shakers and processes data.
V. TEST PROCEDURE
The various tests were performed in the following order in each axis.
1) 0.1 g sine sweep
2) 0.25 g sine sweep
3) Low level random vibration
4) Full level random vibration
5) -6 dB transient
6) Full level transient
7) 0.25 g sine sweep
For a detailed list of test procedures see ST-SIL-TCP-001, December 15, 1982.
VI. TEST DATA AND EVALUATION
Figures 14 through 35 present the control average and e.g. response in eachaxis for the 0.25 g sine tests (pre- and post-), the full-level transient tests, andthe full-level random tests.
Figures 14 through 19, 20 through 27, and 28 through 35 are data from the VI,V2, and V3 axes, respectively.
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A. Sinusoidal Diagnostic Survey
Figure 21 illustrates the center-of- gravity (e.g.) response for the V2 axis forinput in the V2 axis. The fundamental response frequency is 34 Hz. The magnification factor (Q) can be calculated as follows:
Q _ Peak Response Level^ Input Level
0.25 - 2 4~ 2'4
Examining e.g. response data of VI axis, VI input and V3 axis, V3 inputreveals a system response frequency of approximately 35 Hz and a magnificationfactor, Q = 3.
Comparison of the V2 axis pre- and post-test 0.25 g sine sweep data indicatesa positive frequency shift in the post-test data, as in Figure 21. Examination of the"B" and "C" latches after V2 axis testing revealed degradation of the internal inter-face surfaces of the latch halves and particulates in the area around these interfaces.Contact marks were observed on the point "C" bases — SI and FPS (focal planestructure) halves.
B . Vehicle Transient
Figure 16 is an example of the VI axis input for the 5 to 14 Hz vehicle tran-sient test. Figure 17 is the e.g. response for the above input in the VI axis. TheVI e.g. response, 4.17 g's, is well within the fifth cycle load limit of 6.23 g's. Thenumber of cycles is a factor of 3 to 4 due to test control system limitations (sweeprate, rise rate, and control feedback loop).
C. Random Vibration
In each axis the -6 dB random test indicated that notching of the full levelrandom vibration input criteria was not required to maintain e.g. response loadswithin the maximum design limits. Figures 36, 37, and 38 illustrate the inputs intoeach latch for the full level random VI axis test. Fixture resonances resulted inover testing at some frequencies, this may be seen in Figures 26 and 34 — the V2and V3 control averages. In addition, there was over testing resulting from cross-axis fixture resonances at some frequencies above 400 Hz. However, these exceed-ances are narrow band and well above the first fundamental frequency of the testarticle and are not considered significant.
The figures in Appendix B illustrate auto spectral density, transfer function,and coherence plots for selected random vibration time histories. Appendix Cdescribes how the plots in Appendix B were calculated. The following descriptiondescribes the results of frequency domain analysis for the "A" latch in the VI axis:
Figure 39 is an auto spectral density plot for the R2 accelerometer , locatedoutside of the "A" latch. Figure 40 is an auto spectral density plot for the R5
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accelerometer, located inside of the "A" latch. Figure 41 is a transfer function plotfor the energy transfer between the R5 and R2 data. This describes the energytransfer through the latch. Notice that negligible energy transfer occurs above200 Hz. However, below 200 Hz considerable energy transfer occurs. Figure 42illustrates the coherence of the transfer of energy through the latch. Notice thatconsiderable energy transfer occurs only at particular frequencies.
In examining the other H(f) plots and coherence plots, one can see that at somelocations energy transfer was minimal, while at other locations energy transfer wasas much as 95 percent.
VII. SUMMARY AND CONCLUSIONS
A. Summary
Dynamic testing of the space telescope scientific instruments radial latches wasperformed as specified by the designated criteria. The specified test procedure wascarefully followed. No failures were discovered in testing. The alignment stabilityafter exposure to the dynamic environments was within the required tolerances.Participates were discovered in the latch interfaces after testing.
B. Conclusions
Pending positive dye penetrant test results, the latches are considered struc-turally qualified for the flight dynamic environment.
Increased friction due to the worn latch surfaces may account for the frequencyincrease in the V2 axis post-test 0.25 g sine sweep. Another possibility is increasedfriction due to binding produced by misalignment in the V2 axis. The random vibra-tion time history data recorded during the V2 axis test indicated that impactingoccurred at the point "B" and "C" latches. This is attributed to setup error whichcaused the clearance between the bases to be below the minimum allowable. Thesetup error was corrected before proceeding with the V3 and VI axes. No furtherimpacting of latch half bases was observed.
A lubricant must be added to trap participate matter that was produced bywearing of the latch registration interfaces. This lubricant is necessary sinceparticipate contamination of the Space Telescope optical surfaces could render ituseless.
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APPENDIX A
DATA AND ILLUSTRATIONS
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B
i.j
ol
A
C
V2/N
V10
3V3'
A - T R I A X I A L RESPONSE ACC EUE ROMETER
• - U N I A X I A L CONTROL A C C E LEROME TER
Figure 1. Test configuration,
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RADIAL, PT "A", FPS HALF
SHEAR SLUGCOMPRESS IVE STRESSULT LOAD(NOT SHOWN)
BOLTISOLATOR
BALL
BASE 6 AL-4V679-3973
[ \ x-
\ \ \ \ \ i \ \ \ \xx x x x x xx
\FLEXUREBENDING STRESULT LOAD
FPS HUB
STEM.INVAR
"XXX
ALUM. COVERBEARING STRESSULT LOAD
COVER, ALUM." CENTER
Figure 1.1. Latch A, FPS half.
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RADIAL SI, PT "A", SI HALF
ADJ ROD
BOLTISOLATORS
SHEAR PINISOLATION
Figure 1.2. Latch A, SI half.
10
-
CQ^3o-i->03
;.©:; O
f-i
bD
oin
• CN
11
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RADIAL SI, PT "C", S1 HALF
BOLT ISOLATOR
FLEXURE
FLEXURE
BOLT ISOLATORS
SHEAR SLUG
Figure 1.4. Latch C, SI half.
MYKROY AROUNDSLEEVEBEARING STRESSULT LOAD -675
FLEXUREBENDING STRESSULT LOAD
BEARING IN ALUM.COVERULT LOAD
Figure 1.5. Latch C, FPS half.
12
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LIFTOFF COLD CASE LOB37 -- ACCEL. UFPC C.C. — Ul-AXIS
G'S
C'S
C'S
5.B —
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10
FREQUENCY IN HERTZ
5.00 Hz 6 0.10 Cph5.00- 7.30 Hz S 0.078 INCHES D.A. DISPLACEMENT
7.00 Hz S 0.75 CpK7.00- M.30 Hz S 0.300 INCHES D.A. DISPLACEMENT
14.00 Hz ® 3.88 Cpk
Figure 4. VI axis transient criteria.
V2 AXIS TRANSIENT TEST »1SWEEP RATE = 20 OCTAVES/MIN
6.5FREQUENCY IN HERTZ
5.00 Hz 6 0.60 CpK5.00- 5.50 Hz S
5.50 Hz 65.50- 6.50 Hz @
6.50 Hz 6
0.470 INCHES D.A. DISPLACEMENT0.80 GpK0.518 INCHES D.A. DISPLACEMENT1.50 Gpk
Figure 5. V2 axis transient criteria.
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V2 AXIS TRANSIENT TEST "2SWEEP RATE = 24 OCTAVES/MIN
16
16.00 Hz 616.00- 20.00 Hz 8
20.00 Hz S20.00- 22.50 Hz @
22.50 Hz §22.50- 23.00 Hz S
23.00 Hz 6
FREQUENCY IN HERTZ
0.08 CpK0.006 INCHES D.A.0.64 GpK0.031 INCHES D.A.1.00 CpK0.039 INCHES D.A.0.90 CpK
23
DISPLACEMENT
DISPLACEMENT
DISPLACEMENT
Figure 6. V2 axis transient criteria.
V3 AXIS TRANSIENT TEST »2SWEEP RATE = 24 OCTAVES/MIN
18FREQUENCY IN HERTZ
5.00 Hz 65.00- 7.03 Hz 6
7.00 Hz @7.00- 8.00 Hz e
0.60 GpK0.470 INCHES D.A. DISPLACENENT
I.75 GpKI.75 GpK
Figure 7. V3 axis transient criteria.
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V3 AXIS TRANSIENT TEST «|SWEEP RATE = 21 OCTAVES/MIN
X*»
tM
in0.
10.0
1.0
0.1
0.01
0.001
0.0001
FREQUENCY IN HERTZ
II.00 Hz S 0.17 CpKH.00- 14.00 Hz S 0.027 INCHES D.A. DISPLACEMENT
14.00 Hz 6 1.60 CpK14.00- 18.00 Hz S 1.60 CpK
Figure 8. V3 axis transient criteria.
Xf
r"\7
r\ni
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r i i\i
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V
1\
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CRITERIA COWOSHI
95 PERCENTILEDATA
0 100 1000
FREQUENCY (HZ)
Figure 9. Random vibration criteria - 145 dB basis.
16
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130
120
01>01
01ua.
c
I
90
80
70
I 'I I I I I I I I I I I I I I I I I I I 'I
— ORIGINAL CRITERIA
REVISED CRITERIA
10 20 100 1000 10.000
1/3 Octave Frequency (Hz)
Figure 5-2-1: Orblter Cargo BayAcoustic Spectrum
Figure 10. Space shuttle cargo bay acoustic criteria.
1.0
~ 0.1N
•s.»40"̂
QC/JDL
0.01
0.001
0.00011C
X"S"
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FREQUENCY ( H Z )
CRITERIA COHPOSIT!4.6 GRMS
95 PERCENTILEDATA
Figure 11. Random vibration criteria - 139 dB basis.
17
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/RADIAL SI RANDOM.VIBRATION CRITERIA
COMPOSITE: 3.34 Grms0. 1
1 .0E-3
1 0E-4
1 [ 1 1 1 1 1 1
! /:
-
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10 100 1000FREQUENCY IN HERTZ
20 Hz 6 0.00240 g2/Hz20- 90 Hz 6 +5.0 dB/oci90- 200 Hz 6 0.03000 g2/Hz200-2000 Hz S -5.0 dB/oct
2000 Hz S 0.00060 g2/Hz
COMPOSITE = 3.34 Crms
Figure 12. Random vibration criteria.
D>
V2 RADIAL
/ / / / / / T VVI RADIAL
Figure 13. Test configuration.
18
-
CONtROl AWtRACE
POST TEST SUEEP I 1 UP
k^
18 °HZ LOO Sr SI RADIAL LATCHES Ul 55C
Figure 14. VI axis sine sweep control average.
R22 VI CGflCAS DATA' CH 1 • POST TEST SHEEP I 1 UP
an*ST SI RADIAL LATCHES VI .25C
Figure 15. VI axis e.g. pre- and post-test data.
19
-
COKTROL MJfXME
fOST TEST SUEIP t 1 UP
SM
ST SI RMIAl LATCHES VI 5-H HZ VO
Figure 16. VI axis transient control average.
92.2 VI CG R.Tint: CM.n UTHl
20
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. : . M i . i I i ..- : ; | . : - i i : i H.:I : . I J l.i . i
Figure 17. VI axis e.g. transient response.
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-4
CONTROL AUERACEPOST TEST
RltS LEUEl • 3.3*7 G
a SOR/HZ
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ia " ci
5.M
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2889
Figure 20. V2 axis sine sweep control average.
R24 V8m*S DATA< CM SUEEP * 1 UP
It * UNITS
1* * HZ LOG LATCtCS .2SC
Figure 21. V2 axis e.g. pre- and post-test data.
22
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COKTROt AMMCC
POST TEST SHEEP I 1 UP
-1
SM*-3I* "J HZ UK UtTCHES U2
Figure 22. V2 axis transient control average - test 1.
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tej...jj. j/...'.i i.. .*ib
i -:";
i t gHi
.798r -, •-.
. •_. • .' f-
.266y
- ?f-;i':;
- .?332
",73!:!
1 Ml~-
•1 .33
Figure 23. V2 axis e.g. transient response.
23
-
CONTROL AVERAGE
POST TEST SUEEP t 1 UP
1»
-1
1EM 33M
LATCHES U2
Figure 24. V2 axis transient control average - test 2.
K24 V? CG 1G-23 Hz FUN ! I-v-TI '.'2I'lMF.'. CH.H RF.RL V ax is: G" s
i
J
;!
1
•
't -\
!
ij... jj'i
i
!....
-
CONTROL MOMG£POST TtST
RRS LEW. • 3.S73 C'S
ELAPSED TIKE • El SCCS AT .M Dl
DELTA f • 4.883 OOF. 745
-3
aeoaID " HZ IOC ST SI RADIAL LATCHES U2
Figure 26. V2 axis random control average.
-a
-3
R24 U2 CG
POUCR SPECTRAL DENSITY
RRS LEUEL * 3.083
G2'HZ
2MI
II * HZ IOC ST SI RMIAL LATOCS U3
Figure 27. V2 axis e.g. random response.
25
-
CONTROL AVERAGE
POST TEST 5UEEP 1 1 UP
*O* V1
16 ' HZ LOG ST SI RADIAL LATCtCS V3 .3SC POST TE
Figure 28. V3 axis sine sweep control average.
R23 V3 CO
KEAS DATA' CH 2 • POST TEST SJEEP t 1 UP
It ° HZ LOG ST SI RADIAL LATCHES U3 .BC
Figure 29. V3 axis e.g. pre- and post- test data.
26
-
Cl A UTCH 5x2 > 1 UP
-2
s»«e geee-31* JH2 LOtt ST SI RAD101 UTCHES U3 5-8 HZ FULL
Figure 30. V3 axis transient control average - test 1.
R23 V3 CG FULL LEVEL 5-8 Hz V3TIME CH.R RERL Y axis: G's
X axis: s
(Ti c spac i ng: .1 )
Figure 31. V3 axis e.g. transient response,
27
-
Cl A LATCH S/24/I4
POST TEST SUEEP t 1 -UP
1*
18M
ST SI MO LATCHES W II-18H2
Figure 32. V3 axis transient control average - test 2.
:^3 V.;i = . .G n.JI. I.. LEVEL 11-10 Hz V-:i 1NE Ci i .H REHL Y "ax' is: G
X ax i s : s
III I
l . G
.'1
13
•A- .a- 1 . 2
i i.: sp:!it: i 1 )
Figure 33. V3 axis e.g. transient response.
28
-
CONTROL MKBME T8
POST TEST
BIS LCUCL - 3.ttt fl-t
c SOB/HZ
EUPSEO T1IC • 4J 5ECS *T .«* tl
OEIT* F • 4.883 MF> 743 MJF' 32
/\
X
19. S
1* * « LOG ST SI RUIM. LATCHES FULL LEVEL V3
Figure 34. V3 axis random control average.
R23 VI C6
POUER SPECTRKl DENSITY
UK ICVEL • 1.919
GZ/N2
X
-3
HI*
1* ' HZ LOG ST SI RIU)I«l UTOCS FULL LEVEL
-
Ct A LATCH
POUER SPECTRAL DENSITY
RW LEVEL • 3.4M
tt/HZ
_ / \ A
-i
-J
ai i* HZ LOC ST SI RADIAL LATCHES FULL LEVEL VI
Figure 36. "A" latch random input.
C3 I LATCMPOWER SPECTRAL DENSITY
RRS LEVEL • 3.51}
G2/HZ
W
ait!• * HZ LOG ST SI RADIAL LATCHES FULL LEVEL VI
Figure 37. "B" latch random input.
30
-
C3 C LATCHPOUei) SPCCTRAL OENSITV
RRS LEUEl • 3.444
It
-3
it 'HZ ST SI RAOIAl LATCHES FULL LEVEL Ul
Figure 38. "C" latch random input.
31
-
blank
Page /
-
APPENDIX B
DATA ANALYSIS PLOTS
33
-
:.:' Vi M Li l i 'CH n.. RRHOOfl VII ' / K ' '.:.pi::c UM.H v a x i s : (is.':.: I.I X a x i s : Hz
# Mvq: 381
j
i '. ..'.'.'.'.'.'.',''.i
' .
t -
!
1
: :.I
'n
j',
,•,..'
_1 1
I
-
.1.1
f \
It
>
- •
...
'. t; n c. i-;i
% .̂..ft.|...ji
r .i |I T
,'
|V'
ana
•• ivu* w .,
J-fo
1 t:.
|lli
I.....L.ti '
11t 1'()'
,-
i;'.i i£) r i Z
iW !A ! :
Jf ' L •VI '' LTjb^ i «• ) •% 1 ? i
1 v k j l j! iNJ :'l
•.:-.:•::: ::::::!::":?-.:i|51:?.'
: T ' - F f - '"
• • • • i i • • • • : • • '. :•i i : •-- : :•
1000
Figure 39. VI "A" latch random auto spectral density.
l '5 VI. IMS IDE R L.F1TCH f"L RRNDOM VIi liJ ! 0 of- ' f 'C CM. B 'V ax i s : G?.i'.S.'.'i X a x i s : H?.
. ,;:'I ;1 drms b e t w e e n 20 and Ih0y'"hz
• -t
•
- •!
•-
>::.:|1
|
t\ •
f~ ' '
• • ••
[j
= =
:::
...
X
...
!r
|::::
...
...
._
I:::
...
W=f.J
->
' 1
:::̂ ::1.;|l̂|/
J.r i'luv/tw
— •
;•!Jt %^
.. ..
« -T —
1 1
f
1 1
i i i
Mb*i j.-Wl
I i
::::
ft
. .,
*:;'".:.;
....;,..
=
:tVi
.;..
. t.'Li •:.
i:< i
Figure 40. VI inside "A" latch random auto spectral density.
34
-
R'5 VI H LFITCHESP HI
Fl RF1NDOM VIY ax i s :X a x i s : Hz* Flvq: 381
clj
Figure 41. "A" latch transfer function.
--.? ;;:/ -- . ' I R LHTCH \ - \ . RiiNDufi vi
'•'
•;. ~i•-* n./g: 3:3
i - ' , /.s&m
1000
ga
Figure 42. "A" latch coherence.
35
-
-•':.: VI P, I..IHCFI FL RRNDOri VIr i I'O i:;L'L( (":H.R V axis: Q?.,
•-' •.-;!:! X axis: H?-ft Hvg : -123
'! .-f:-:! !it in? between 20 and 1C MM bz
1008
Figure 43. VI "B" latch random auto spectral density.
i - 'M VI ING1DE B LRTCII FL RRMJX.UI VInuro v-;r^:c CM. B
X ax i •'.• : Hzt R \ / c :
••i . U4 Gr-ms be tween ^Q and 1600"!
Figure 44. VI inside "B" latch random auto spectral density.
36
-
:: v& Rll VI B LflTCHPi;'-' RC'SP Ml HUG
FL RFlNDOfl VIY a x i s :X ax i s : Hz:# Rvg: 423
Figure 45. "B" latch transfer function.
] VI (3 I...ill CM FL HRNin. iM V
i
1
1
1
£Q
! I..I
,'
\ j
JU-
i
1111
|
1
*! 1
/[
|
| .
.
f| '
,'
1
fit*\
\
...
...
1
'/
••
.... 4it
IU''
\
A{
\]
i
iji
i;
!
, :
J|
1 fiill
It 1 1II ij' i
a xaxRv
i s ::J :
1:
. . . :
ii1! IS
1; t\.r :ii *3 :!JM ):li;jt
Hz
t I
1Jj
i
1 ?lî-.1
;lPi
Figure 46. "B" latch coherence.
37
-
! • ' ! ' ? VI C I RICH FL RFINDOM VI• s | - , , •".-; j.•:.[:: f ,;;| j _ j. ( V ax i S :
• Ti X a x i s :* Rvg:
•'•'. H .'•"' 'T: ins hetujeen 20 andI
Figure 47. VI "C" latch random auto spectral density.
° i i - Vi !N \JJ ] )E C LHTCI1 FF RRr-llJOH VIax s: j:-.
X a x i s : Hz# flvcj: 42P1
CntT!!5 ; be tween ^0 and 1600 hz
Figure 48. VI inside "C" latch random auto spectral density.
38
-
vs R17 VI C I..RTCH PL RRNDOI1 VIA RflSP HI NRG Y ax is:
X ax i s: Hztt Rvg: '120
rn 'J ! '1
Figure 49. "C" latch transfer function.
\ < } 7 '••?'[ c i . - i 1 1
t-Iz£01
Figure 50. "C" latch coherence.
39
-
..i VI .M UTTCHI ' i i G SPCC CH.fl
.:! . •! Gi i'iV:": bet i.uee
..
1
i
i
...,-. .• ll1'
: i-...|....|...
....j i.U.'.U/
J
f4
tt
... .
J
....
...
"
FL ^'FIND-ON VIY a x i sX ax i ;-:t Rvq
n 20 and 1600 hi
|...J
ii
••••* •>
Ml ': I
M f1L"|-: I 1: [ j
: |J
i
1
V::::::̂ r
nf\
: 0. : 1-
4c
•"tc" •-7
f j
.. .A... j... ;..
J
\\
. . .
(L i
ll
.f...ft10013
Figure 51. VI "A" latch random input auto spectral density.
G r m x
FL RHNDON -VICH.B V a x i s :
X ax i s :t llvq:
between 2(!\ a n d I '
Figure 52. VI e.g. response auto spectral density.
40
-
( .1 22 V )RF.SP HI
FL RRNDOM VIMRG Y axis:
X axis: Hz# Hvg: 428
• i ii,
'•-̂ .n?1 000
Figure 53. VI "A" latch input versus e.g. transfer function.
1 II. RRNMON V iY ax i sX ax i st Rvq :
Hz
•V
1809
Figure 54. VI input versus e.g. coherence.
r;
4
41
-
R •! V? R LRTCH PL RHNDOM V2nuro SPEC CH.R Y a:
# Rvq: 381• " ! . f - - i ? ( T i m s between 20 .^nd 1G0U l..i
? PI
Figure 55. V2 "A" latch random auto spectral density.
Pb V2 JNGIDE R LRTCM Fl. RRNUON V?MI..HO SPEC CH.B Y axis: r;£i'-'SU X axis: Hz
t Rvq: 381S . f t H Grins between £0 and IGOy hz
Figure 56. V2 "A" latch inside random auto spectral density.
42
-
RG- V? R LRTCH:•?!•: o Rf-:f.;;p HI MRG
f:L KRNDOM Vi?V ax i s :X axis: Hz* Rvg: 391
Figure 57. V2 "A" latch transfer function.
.' " 11 '.
• r - l ,-!•
;ii " 1:
*t• • •'• .- . ••
i! ;
i • i'
.. , i
| :T. f
11
!i(\
i
'"!I
- ..
. 1 :
1 r ""-. i "»
••CI
''•
i «
~]!
r
ii (
• ._
..f l l 'CI-
::lCn ;/\i
!1
i " l . Pl lV
stti1
IIt
J^
f ••! 1 1
Hv
1i i
II
I •-
t;
XA
1iI
i r
• •
, j1
h.i
|
fl
li. I
:-?M !;il"lt"l
Figure 58. V2 "A" latch coherence.
43
-
.' '? '. V
I IJIO:'SJJ
"; . :'-: 1
..-•—•--.
;.' B LRTCH I"!. RRNDOM V2SPEC CH.FI Y a x i s : G
X ax is: Ht- R v y : 42
Grrns between 20 and 1G80 hz
,
• • "i •:•- ••-! - - - i - - - i - - - i - - - - :•
_.•-"'.1 •• i
,'•••
<
,'\
...
,
:::::::::;;:::::::::::ft/ L! "i
'i /V'J ii[i ,.<
i i i-
^iMi i" ;if flAfl
i1 il i ff i L i J
i\V'
•• :
J
1
• i::
C.
"i.1
t
•1 !
cU
Figure 59. V2 "B" latch random auto spectral density.
- ' i ' J ' - . • • : I f . l ' j l JJE B [..RICH /I. RRNDOM Vr:R U I O sPSrr t :H. B Y ax i s : G?/!kr-'3i:i X ax i s : Hz
* Rvq: 423'":• , ' . - -1 Grnr>; b e t w e e n 20 acid IGMO'hz
Figure 60. V2 "B" latch random auto spectral density.
44
-
R,1 vs RIO V2 B I..HTCHFfciro RIL'SF* HI MflG
' l i
FL RhHDOrV ax i s•
Vc'
I 1,
Figure 61. V2 "B" latch transfer function.
B I...HTCH FL r'RNlJON V.1V . a x i s :X a x i s : Hz* rivci 423
Figure 62. V2 "B" latch coherence.
45
-
ifri o' 'SD
'-'I '•".
" "--••:.
V? C 1 IT! CH FL RRNDOM '•/?.SPEC CH.H ' V a x i s
X ax i s# _ Hvg
Gria;~ between 20 and Ib 00 h.
,-?
..'"
fJ
f
..-
,'
1 '
• •
v1'1 |l'4
...
f\ Ltr-;- "Virrl
L i\ j 1 IV
ijLr K ,fV
rr •• i
'b fit I.
:
:i":i:||I|::.::..:.::. :::.:.] . :.|.
•
z
ll
hiz"i r*ir> t.i
V '11 t
1I100
Figure 63. V2 "C" latch random auto spectral density.
R : ' G ' V ? INSIDE C I .RICH Fl. . R R f J D O M VPH I ! T O SPEC C M . B V a x i s : G?/'l!;"oIJ X a x i s : l-lz
t R v q : -r.;:^•i , 1 J Grrns be tween 'dR and 1 6 0 W " h 2 . ' j 4 Q
* i _ ~ L '
. nn i :;if-;
Figure 64. V2 "C" latch inside random auto spectral density.
46
-
U!13 vs RJb V2 C LRTCH FL RRNDOH V2!>?rn RTSF'1 111 MRG V a x i s :
X ax i s : Hzt Rvq: 43ft
Figure 65. V2 "C" latch transfer function.
RJB V:-? C I..RICH F"L RRNIi'.'
.5
1UU0ii
Figure 66. V2 "C" latch coherence.
47
-
'1 '« '
:•: . \?.
' .- "
L'-n
? .i'i 1..H
!. i r ! ri 5
. ....,'.
_.!'
•TV ... .f
f i
TCH FL RRNDOM V2•Jl-!. R Y a x i s
X ax i st Rvq
b e t in e e r i 20 a n d 1 6 0 0 " 1
>
•••••-•:• - -
>v'/
.'i
—
...
...
...
1 J1 \ • i
M'\, I'V1 f Iau• "J
i :::::::::::
,::":::::::::::.:... .:...j •I,!il nlTra llj 1
l/» HiM tlB .1.
....
11
•
1 Z
I"
;_
10f
Hz98
J1ft
'1
*|
. £?. ':i:.:.i
;:;^j . HHU;-T,f-30 - - -
Figure 67. V2 "A" latch random input auto spectral density.
tt?.'t V? CG FL. RflNDOM V2MUTO Si-EC CH.B Y a x i s : G2-r'-JU X ax is: Hz
# Rvg: 398_'• i ' L"' i""" .- «.-. ... I.. — -L . . —, _ ... ""i i"Ti _ ... _1 1 i"' f~Jti~T-t I.. .._
*"'.
"\
\...\
" "
"
....
...
—
L-'
. .,
-
....
£
....
—
•-
:f
/'...
...
...
P.
Alr.V./ . ..,.
,::::::::f::-.::::l:-:::j
:̂:::=--
'
,1 if
;.'lil:::"
J:::Mm1 lii
::::::::::::.:::|
1
.I::::::,:::,
t::::- : :
..11 1
..%fl?
-i i-- -- i • • • • j
•
. : i •::
:i:l:::n;inIt
i'l frJi
= 1•!v:: ''
|
•:
~ .:.....;...
48
Figure 68. V2 e.g. response auto spectral density.
-
FLRHNnOH V211
_I IMG a x i s :
X ax i s : Hz# Rvg : 39o
1000
Figure 69. V2 input versus e.g. transfer function.
.ONE U'LNct:F'l. PRNDOM V;'1
Figure 70. V2 input versus e.g. coherence.
49
-
R 2 r 3 ' V 3 R LFITCH F'L RHNDOM V3FlUTO SPL'C CH.R Y a x i s : G2-I'-'SD X ax i s : Hz
* Rvg: 315' • ••- . . '~>' .- \ Ojrrns between 2W and 1GOW hiz
Figure 71. V3 "A" latch random auto spectral density.
•1 V:-; INS I LIE R LFITCHU4u sr;'i:C CH.B
F'L RHNUOM V_Y ax i s : Qc
>ii X ax i s : Hi# Hvg: 31
' j 5 Ci r • i i i s b e t u.i e e n 2 0 a n d 1 G Q H f't 7.l t '3
nf-u:i: :Sh
Figure 72. V3 "A" latch inside random auto spectral density.
50
-
.3 R4 V3 R LHTCHRP'SP ill MRG
Ft. RflNDOM V3V a x i s :X a x i s : Hz# Rvg
1000
Figure 73. V3 "A" latch transfer function.
K?5 vs R4 V3 R LRTCHco i I[.:RQ,ICE
X ax i s : Hz* Rvci US
, C J
. 1
H
Figure 74. V3 "A" latch coherence.
51
-
RM V3 B LRTCHi-iuro SPEC CH.R
PL RRNDOM V3Y a x i sX a x i st Flvq:
Hz3.8B
- -. c• . i -. i G r- in s b e t w e e n 2 0 a r "i d 1 R l/i 0" I ( z
Figure 75. V3 "B" latch random auto spectral density.
Ric V3 INSIDE B LRTCH PL RRNDOM V3i'UJ'IO SPEC CH.B Y axis: G5/1P'Sl.'i )( ax i s : Hz
* Rvq: 28G:•'. II 'or ms between 20 and H.-i00 hz
n
. i-!C20 1000
Figure 76. V3 "B" latch inside random auto spectral density.
52
-
R12 V3 B L..RTCHRE3P HI NRG
FL RRNDOM V3Y ax i i? :X ax i s : Hzt Rvq
Figure 77. V3 "B" latch transfer function.
RH v- R12 V3 B LilTCH PL. RRNIJOM V:, . ' , ' i - i l :
.
. ..':•--.. ii *
?y
KI- . . I
r. 1'i /
I1 •.1- .t
Ii1*J1
I/
t
'
,'1
AV\ 1 i1
'l
|
1
.I1
\||'
i Li'in i1'.\ \
••• iilln
i\ f
j* .jM
•-j. X
?i >.'
1, J.•w
i :--: -
ilP
\%
n
;;
,i
I'J
i :
IIk"Jlf
1I
(nJ If f
1
l \
1 1. l.l
. !
V.
.1. 1
.•)
K 1.
1, I.1-1
Figure 78. V3 "B" latch coherence.
53
-
;M VJ C I .RICH El.. RfiNDOM V3|!.iTO SPEC CH.R . Y ax i s : Gel.'SP X a x i s : I-la
=11= Rvq: 260
/'.•
u r
i ...-
• I l l - :
i1*
.. ..%
,-••
D C
>.... .
• -^
r'
1 1 LI.
....|....
•^
— i —
....!• ..
.(...
....|....
F
...
t)'
...
• -•...
e n c w
,rj..̂
a n a
•;
%::::wfl
1 b
i,M »r
^n
Lll
::|
ll
1V
... .
... .
:J
••
-•
••
I
• -
n zi
1 4
! ! i
I
k(1̂ - 4
T
...,.;.-...
,.....>..̂
> ...fr--'
.... A ...
1 iif:.:
riP,ll
^ - >
J1
I IB
IE
Figure 79. V3 "C" latch random auto spectral density.
RIO V3 INSIDE C I..HTCH Kl Rnt--inon .nUIC' SPEC CH.B Y ax is : GXpr.^D X ax is: |-!y.
* Rvq: : -?eS-py1:' Grrtis between ^0 and "
Figure 80. V3 "C" latch inside random auto spectral density.
54
-
;-:H vs RIO vs c LfiTci-i!"kl::0 'RCSP HI MflG
FL RRNDOM v;7;Y axis:
ax i *L
• n
Figure 81. V3 "C" latch transfer function.
RJ8 V3 C LHTCI-I F"L RRNDOM V:1.!JCL Y ax i s- :
X ax i s : hlz* R v q : 268
10UU
Figure 82. V3 "C" latch coherence.
55
-
Cl V3 R LRTCH F~L RRNDOM V3MUTO SPEC CH.R Y axis: G2P'-P X axis: Hz
* Rvcj: ?7b':j.:"'3 Grms between c(3 and 1G00 h?
Figure 83. V3 "A" latch random input auto spectral density.
!:VJ V3 CG FL RRNDOM V3HI.I"10 Spf-'C CH.B V axis: G2.PSD X ax i s: Hz
# Hy9 : ^?flI . !'-!:fi i.ir'Tiis be tween i-ilU and 1UW0 hz
1000
Figure 84. V3 e.g. response auto spectral density.
56
-
P23 V3 FL RRNDOM V3ESP 111 NRG Y axis:
X axis: Hz# RYU: 276
Figure 85. V3 input versus e.g. transfer function.
KL RflNJ'iOHax i •ax iRvt]
.11
Figure 86. V3 input versus e.g. coherence.
57
-
Page intentionally left blank
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-
APPENDIX C
ANALYSIS EQUATIONS
59
-
Correlation is a measure of similarity between two vibration waveforms. It isused to detect hidden periodic signals in noise and to determine other informationsuch as energy transfer, etc.
An autocorrelation analysis multiplies the ordinates at time, t, and t + T (a timeshift), then time averages. Autocorrelation is defined mathematically as follows:
RXX(T) =^m Y f X(t) X(t + T) dt
T/2
f-T/2
An autocorrelation of a random signal using a small T will tend to highlight theresonances of the system. Cross correlation is a correlation between two differentwaveforms. It is defined mathematically as follows:
RX Y(T) = f X(t) Y(t + T) dt
T/2
f-T/2
Once time domain analysis is completed, frequency domain analysis can begin.The auto spectral density (a power spectral density of the autocorrelation) is definedas follows:
G x x ( f ) = 2 /Rx x(T)e-i 2 r f T
The cross spectral density is defined as follows:
Gxy(f) = 2 / RX Y(T) e ""il dt
The cross spectral density determines frequencies of greatest transfer.
Coherence, in the frequency domain, is analogous to the correlation coefficiento
in the time domain. Coherence values of YXY < 1 indicate that the response is not
attributable to the input. Coherence describes the percentage of energy transfer atany particular frequency. It is defined as follows:
60
-
" GXX< f ) Gyy(1) *
A transfer function describing energy transfer through a system can be cal-culated as follows:
GXY ( f )
Gu
61
-
APPROVAL
RADIAL SI LATCHES VIBRATION TEST DATA REVIEW
By Phillip M. Harrison and James Lee Smith
The information in this report has been reviewed for technical content. Reviewof any information concerning Department of Defense or nuclear energy activities orprograms has been made by the MSFC Security Classification Officer. This report,in its entirety, has been determined to be unclassified.
G. F. McDONOUGHDirector, Systems Dynamics Laboratory
62•&U.S. GOVERNMENT PRINTING OFFICE 1984-746-070/10012