- 1. SAR-LINE Method - A new method forSqueak & Rattle
simulation and testdeveloped at SAABJens Weber, Ismail
BenhayounSaab Automobile AB5th European HyperWorks Technology
ConferenceBonn, Germany 2011November 8th 9th Page 1
2. Squeak & Rattle (SAR) causesManufacturing Material
pairsAssembling Surface finishing Relative displacement Temperature
TolerancesRoad load Humidity Jens Weber, Ismail BenhayounPage 2
Ref: SAE 2010-01-1423 3. Instrument panel (IP) assemblySAAB 9-5
Jens Weber, Ismail BenhayounPage 3 Ref: SAE 2010-01-1423 4. IP
assembly on quiet shaker F(t) Deformation scale factor 50 !Jens
Weber, Ismail BenhayounPage 4Ref: SAE 2010-01-1423 5.
ParametersGlobal stiffnessLocal stiffnessClips/snaps
stiffnessContact / gapLoad Rel disp in local Coordinate System (CS)
LoadRelative displacement SAR-LINESAR evaluation Jens Weber, Ismail
BenhayounPage 5 Ref: SAE 2010-01-1423 6. Global stiffnessModal
correlation Test - FEM123 7 4 6 89 5 10MAC 12 11 1413271516 20
263228 1721 29 1819 2233 23 3024 31 25- Only the lowest modesFoil
(shell)are represented- Improved material data for plasticand
foam/foil (Youngs modulus)Foam (solid) Jens Weber, Ismail
BenhayounPage 6 Ref: SAE 2010-01-1423 7. Modal correlationLaser
Scanning Vibrometer Jens Weber, Ismail BenhayounPage 7 Ref: SAE
2010-01-1423 8. Local stiffness MAC valueSimulation with shell
elements:- thickness: t ~ k(E,t)/m - mass: m - Youngs modulus:
EMode # Simulation [Hz] Simulation [Hz] Test [Hz] MAC value [ -
]2130 MPa2600 MPaTest 113.815.3 15.0 0.98 218.920.9 21.2 0.95
324.126.6 25.7 0.98 431.434.7 35.3 0.98 542.246.4 46.3 0.98
648.653.7 54.9 0.89 761.668.1 68.4 0.94 865.172.0 72.9 0.93
978.386.5 87.5 0.841085.093.9 95.0 0.87 Jens Weber, Ismail
Benhayoun Page 8 Ref: SAE 2010-01-1423 9. S&R Cockpit test on
quiet shakerGlobal stiffnessLocal stiffnessClips/snaps stiffness
LoadContact / gap LoadRelative displacement Rattle v Squeakw
[m/s2][mm]Part I uQZ P T [s]YT [s] GAP Part II Samplings frequency
SFXJens Weber, Ismail BenhayounPage 9Ref: SAE 2010-01-1423 10.
Contact / gapSAR-LINE method Local CS: x rattle- aligned to master
surface - assigned as analysis CS to node # 1001 and 2001Master
surfacez squeak1001RBE33D line (SAR line path)RBE3 Slave surfaceTCL
script in HyperMesh 2001SAR line numbering convention:SAR line #
1065: 1001 / 2001 to 1065 / 2065SAR line # 3099: 3001 / 4001 to
3099 / 4099 ....Jens Weber, Ismail Benhayoun Page 10Ref: SAE
2010-01-1423 11. Contact / gapSAR line RBE3Local CS RBE3SAR lines
Jens Weber, Ismail Benhayoun Page 11 Ref: SAE 2010-01-1423 12.
Input signalPSD load definitionfor quiet shaker tableTime signal
length? Time signalJens Weber, Ismail BenhayounPage 12Ref: SAE
2010-01-1423 13. Time length of input signal vs relative
displacement Jens Weber, Ismail Benhayoun Page 13 Ref: SAE
2010-01-1423 14. Post processing relative displacement using
HyperGraph Rel disp in node 1001-2001Max value 0.45 mm + Gap
closing - Gap opening T=3s Ranking the peak amplitudes Mean value
0.19 mm20 % Mean value of 20 % of highest peak amplitudesJens
Weber, Ismail BenhayounPage 14Ref: SAE 2010-01-1423 15. Analysis
processFFT - Frequency response - iFFTdelta f = f(SF, T, 2n)TLOAD
(random signal) Displacement in local CS (LCS)in time domainin time
domain on SAR lineRADIOSSModal transient analysis Load TSTEP = 1/SF
Displacement in LCS[m/s2][mm] T [s] T [s] Samplings frequency
SFJens Weber, Ismail Benhayoun Page 15Ref: SAE 2010-01-1423 16.
SAR-LINE evaluation process InputOutputNode pairs on SAR lines:
Relative displacement (max or % value of highest peak
amplitude)*.dat file Purpose Comparing design variants : material,
mounting points Correlation to rattle and squeak occuranceGRID node
#X Y Z 3D contour plot of all SAR lines showing the magnitude of
rel disp Global Ranking all SAR lines (Histogram)Results on SAR
line Relative displacement along the SAR line (in LCS)*.pch
*.matLine User option: Magnitude, Squeak, RattleDisp T1/T2/T3 in
LCS Relative displacement at each node pair in time domain
PointTime = time length of input signal Ranked amplitudes Jens
Weber, Ismail BenhayounPage 16 Ref: SAE 2010-01-1423 17. Global
level - Contour plotJens Weber, Ismail BenhayounPage 17Ref: SAE
2010-01-1423 18. Global level - Ranking SAR Line ranking -
Magnitude - Mean over 30% highest values (HV) 0.141 mmLine
13094Jens Weber, Ismail BenhayounPage 18Ref: SAE 2010-01-1423 19.
Line level zLocal CS in each ySAR line point 70017027 Node 7001
Node 7027Node 7001Node 7027Jens Weber, Ismail BenhayounPage 19Ref:
SAE 2010-01-1423 20. Point levelNode 7015 and 8015 z y Mean value
over 30 % HVJens Weber, Ismail BenhayounPage 20Ref: SAE
2010-01-1423 21. Ranking comparison of design variantsVariant
1Remove mountingpointVariant 2Change material fromPP-LGF30 to ABS
PC Jens Weber, Ismail Benhayoun Page 21 Ref: SAE 2010-01-1423 22.
Line - comparison of design variantsVariant 1Node 3035Remove
mountingpoint Node 3001Variant 2Change material from Node 3001 Node
3035PP-LGF30 to ABS PCJens Weber, Ismail Benhayoun Page 22Ref: SAE
2010-01-1423 23. Gap line vs contact lineContact line Gap
lineRattle correlation Squeak correlationPeak amplitude > Gap
size Peak to peak amplitude > 1/Impulse ratePeak to peak
amplitude Gap sizeRel disp in contact plane Jens Weber, Ismail
BenhayounPage 23 Ref: SAE 2010-01-1423 24. Rattle correlationRel
disp in node 1001-2001 gap = meancrit Ranked peak amplitudes when
rattle sound starts?% Rattle occurs when gap = meancrit value of ?
% hightest peak amplitudes TEST SIMULATION Displacement measured
with Displacement simulated with 3D Laser Vibrometermodal transient
solverF (t) F (t)Jens Weber, Ismail BenhayounPage 24Ref: SAE
2010-01-1423 25. Rattle correlationJens Weber, Ismail BenhayounPage
25Ref: SAE 2010-01-1423 26. Rattle correlationJens Weber, Ismail
BenhayounPage 26Ref: SAE 2010-01-1423 27. Squeak
correlationdate10.08.2007time12:19:02 stick-slip test
standparameters15 20 normal force50,3 Ntemperature25,09 Chumidity
54,06 % rel. F. 15rel. velocity5,8 mm/sRelative velocity10 10
stick-slip riskRPZ10 512 3 456 7 8 9 105grade groan rate 10,33
00grade acceleration 27,00grade impulse rate5,72 - 5-5 max. accel.
22,1 ggroan rate0,10 kHz -0 1impulse ratetesting duration 1,426,1
1/mm s Impulse rateimpulses 212-01 -5 1dyn. frict. force8,3 Ndyn.
COF0,17-51-0 2 -0 2 -5 1-01- 5 - 0stat. frict. force13,4 N acce e r
ton [ ]l a i g r se t f rce N ]eo [ m o t rs t t s o ausstat. COF
0,27version 2.00Jens Weber, Ismail BenhayounPage 27Ref: SAE
2010-01-1423 28. in contact planeSqueak correlation Relative
displacement (in contact plane)Peak to peak amplitude 1/Impulse
rate < peak to peak amplitude0.44 mm Relative velocityMax value
Relative velocity max relative velocity22 mm/s Jens Weber, Ismail
BenhayounPage 28 Ref: SAE 2010-01-1423 29. SAR-LINE applications
interior / exteriorJens Weber, Ismail BenhayounPage 29Ref: SAE
2010-01-1423 30. SAR-LINE applications interior / exteriorVolvo
3PBy courtesy of Volvo 3P Jens Weber, Ismail BenhayounPage 30 Ref:
SAE 2010-01-1423 31. Interior design processStart of
productionVirtual engineering ValidationModal analysis Pulse
analysis (Global CS) SAR-LINE analysisRoot cause analysis / test
supportJens Weber, Ismail BenhayounPage 31Ref: SAE 2010-01-1423 32.
Tack s mycket!Jens Weber, Ismail BenhayounPage 32Ref: SAE
2010-01-1423
