RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise...

25
2.10.2007 MTE Analysis of Gears RotasPro Gear Test and Noise Analysis

Transcript of RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise...

Page 1: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

MTE Analysis of Gears

RotasPro Gear Test and Noise Analysis

Page 2: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

The company was founded in 1985. It is situated in Göttingen in the heart of Germany. Since 1989 the main product are measurement system for the acoustical quality analysis. There are 24 employees and more than 400 test systems deployed.

Base system are ROTAS and MESAM-4 (a joint development with DaimlerChrysler). Build on top of them are APAS for the cabin noise analysis, ROTAS-GP for the analysis of gearboxes and transmissions, ROTAS-ZP for the gear test, ROTAS-TMO for the test of tapered roller bearings.

MESAM 4

APAS-II

Base System Gearboxes and ComponentsCabin noise

ROTAS-Mobil

Discom Industrial Measurement Inc.

Page 3: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

ZF DGear Testers 4 Systems

Volkswagen D,SA,AR, China,B,SK,BRGearboxes, Transmissions, Gear Testers, Cabin Noise Production Database, 165 Systems

Tongil, KoreaAxles, Durability test Stand, 1 System

SFT, Magna Stey PowertrainAxles and gearboxes 28 Systems

Skoda, CzGearboxes, 7 Systems

SAIC Shanghai Automobile InternatiolCorp.Gearboxes test systems, 4 Systems

SKF D, USA, India, UkraineTapered Roller Bearings, 26 Systems

Robert Bosch Starters, injection pumps, production database 6 Systems

Renault, PeugeotTransmissions, 5 Systems

GM, USA, Opel D and AGearboxes 14 Systems and Axle Testers 25 Systems

Jatco, JapanCVT Transmissions

Discom: Customers and Applications

Fiat, Iveco, TataManual Transmissions 7 Systems

Getrag, USA Sc, Single Flank Gear Tester for Cummins Engine Gears with Tors. Acceleration

Graziano, Italy Gearboxes and Axles for Audi, Aston Martin, Ferrari, Lamborghini, Maserrati

Gearbox, SPgearboxes, gear testers 12 Systems

Ford, DGear Testers 4 Systems

First Automobile Works, ChinaGearboxes 1 System

DaimlerChrysler D, US Cooperation MESAM4, gearboxes, transmissions and engines. 36 Systems

Borg-Warner, USA,UK Transmissions und Axles 8 Systems

Bentley, UKCabin Noise Analysis APAS, 2 Systems

American Axle, USAFront and Rear Axles, 5 Systems

Hyundai, KoreaGear tester 2 Systems

Cummins

Page 4: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

MTE/Torsional Acceleration Measurement

n

M

3000

0

0

50 60 70 80 90 100 110 120 130 Ord

40

50

60

70

80

dBV

Mix

Antrieb

GM

2 *GM

GhostOrders

Test Sequence is steady speed or ramp

Mechanical Layout of Test MachineRotas NVH Analysis

TorsionalAccelerometer

40 Nm 10-40 Nm

Tested Gear

t

t

15-20 s

Page 5: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Revolution Synchronous Transmission Analysis

Input Shaft Interm. Shaft Output Shaft

The transmission noise is the sum of the noise originating from the individual mechanical components.

For the gear noise components, the individual sources can be isolated by the transmission ratio.

Synchronousorder analysis:The signals are acquired synchronousto the inner shafts.AcousticalStroboscope

Input Shaft

Interm. Shaft

Output Shaft

Page 6: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

400 800 1200 1600 2000 2400 2800 3200 3600m Rev

-16.0

-8.0

0.0

8.0

16.0

g

ZwAn

-16.0

-8.0

0.0

8.0

16.0

g

ZwAb

-16.0

-8.0

0.0

8.0

16.0

g

TsAb

Synchronous Averaging II

Nicks are shown in the synchronous channel that is synched with the offending shaft.The nick detection is based on the Crest value

Crest = Peak value/RMS value

AG4 V4.0 Typ 39 Unit 67 04.Jun'2000,17:10:16-------------------------------------------------------------------Code Description Gear Is Lim Av Unit Kx448 NICK 3.-Gear / Up 3-Z 16.8/ 12.0/ 9.5 Crest ZwAn--------------------------------------------------------------------

AG4 V4.0 Typ 39 Unit 67 04.Jun'2000,17:10:16-------------------------------------------------------------------Code Description Gear Is Lim Av Unit Kx448 NICK 3.-Gear / Up 3-Z 16.8/ 12.0/ 9.5 Crest ZwAn--------------------------------------------------------------------

Page 7: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Torsional Accelerometer

gez.:J. Lorenz

Rotierender SensorAbmaßeAluminium/Kunsstoff

ZEICHN.NR.041220-0MASSTAB 1:1 2004-12-20

BLATT 1 von 1

DIS COMMATERIAL:

Tel=0551/548330Fax=0551/5483343

Sender

Empfänger

Lagergehäuse

20,0

0

Ø70,00

Ø22,00

Øyxx

38,00

32,0

0

Sensor

110,

00

125,00

35,00

25,00

45,0

0

90,0

0

10,00 10,00

Rotational ensorAccelerometers

LED Sender

Optical Receiver Power TransformerInto Rotator

gez.:J. Lorenz

Rotierender SensorEmpfänger- Gehäuse

AluminiumZEICHN.NR.050103-6MASSTAB 1:1 2005-01-03

BLATT 1 von 1

DIS COMMATERIAL:

Tel=0551/548330Fax=0551/5483343

90,00

35,00

110,

0090

,00

R 12,00

R 14,00

R 13,00R 16,00

R 2,00

Nut 1x2

Nut 2x2

35,0

0

24,0

0

2,50

10,0010,00

10,0

010

,00

4x d=5,1

R 4,00

2x M2,5

30,0

0

5,00

Deckel 10x34,8x5

R 35,00

Nut 1x2

30,0

0

2x Bohrung u. Senkung M2,5

1,002,005,00

20,0

0

10,0

0

Ansicht von oben

2,50

53,00

10,00

3,00

3,00

18,5

0

R 35,00

R 32,50

Page 8: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Torsional Accelerometer

Rotating Sensor

Accelerometers measure the deviation from uniform circular motion

Optical SenderOptical Receiver Power TransformerInto Rotator

Accelerometers

Page 9: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Test gear

Master Gear

Torsional Accelerometer

Single Flank Gear Tester Linnenbrink

Page 10: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Engine Gear Tester Getrag / Cummins

Page 11: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Results from Crank/Cam Gear pairs

0.00.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Rev

V.V

-0.3

-0.2.-0.2

-0.1.-0.1

0.0.0.0

0.1.0.1

0.2.0.2

Crank

0.00.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Rev

V.V

-0.3

-0.2.-0.2

-0.1.-0.1

0.0.0.0

0.1.0.1

0.2.0.2

Cam_Shaft

0.00.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Rev

V.V

-0.3

-0.2.-0.2

-0.1.-0.1

0.0.0.0

0.1.0.1

0.2.0.2

Crank

0 00 0 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 9 Rev

V.V

-0.3

-0.2.-0.2

-0.1.-0.1

0.0.0.0

0.1.0.1

0.2.0.2

Cam_Shaft

Good Gear Set

Crank Gear

Cam Gear

0.00.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Rev

V.V

-0.24

-0.16.-0.16

-0.08.-0.08

0.00.0.00

0.08.0.08

0.16.0.16

Crank

0.00.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Rev

V.V

-0.24

-0.16.-0.16

-0.08.-0.08

0.00.0.00

0.08.0.08

0.16.0.16

Cam_Shaft

Eccentricity onCam Gear

Nick on Cam Gear

Graphs show one revolution of the crank and the cam gear when run as pairs on the single flank gear tester. The faults can be easily detected.

Page 12: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Comparing DIN 3960 composite inspection

Fi’ tangential composite deviationLong wave component

Fi’Fi’

fk’ tooth to tooth deviationshort wave component

fk’ fk’

Good Gear Set Eccentricity onCam Gear

Graphs show one revolution of the cam gear when run as pairs on the single flank gear tester. The good and the bad gear set show less variation with this method. Fi’ is even smaller for the bad gear

Page 13: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Separation of Gear Errors

The acoustical signal holds the components of both gears.

Knowing the transmission ratio, the periodicity of each gear can be found. Gear mesh components only depend on the pairing of the gears.

Eccentricities and surface errors can be separated because they have a cycle that corresponds to the originating gear. The following errors can contributed individually:

� Eccentricities, � Deviation from circular shape� Tooth spacing� Surface waves (Ghost Orders)� Nicks

Z1

16

Z2

20

Z1

16

Z2

20

The gear mesh componentdepends on the pairing

Eccentricities and surfaceerrors can be contributedindividually.

16

20

16

20

Page 14: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

50 60 70 80 90 100 110 120 130 Ord

40

50

60

70

80

dBV

Mix

Antrieb

Revolution synchronous averaging gives periodic (cyclic) signals. This corresponds to the cyclic nature of the gear sets.

These signals can be transformed into the spectral domain without any time domain leakage windows.

This allows for high spectral resolution. Eccentricities can be easily distinguished from the gear mesh orders. The noise components can be attributed to their origins.

Blue: Conventional order spectrum with Kaiser Bessel Window

Green: Revolution synchronous order spectrum without window function

Synchronous Averaging III

GM 2 *GM

Ecc.. GhostOrders

Page 15: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Results from Single Flank Gear Tester

und PrüftechnikIndustrielle Meß-

Crank No 30-4005.04.05 10:19

0 20 40 60 80 100 120 Ord 10 15 20 25 30 35 40 45 50 55 60 65

dBV

Spectra / Pz1 / SK1 / SpecReport

0 40 80 120 160 200 240 Ord 10 15 20 25 30 35 40 45 50 55 60 65

dBV

Spectra / Pz1 / SK2 / SpecReport

0 20 40 60 80 100 120 Ord 10 15 20 25 30 35 40 45 50 55 60 65

dBV

Spectra / Pz2 / SK1 / SpecReport

0 40 80 120 160 200 240 Ord 10 15 20 25 30 35 40 45 50 55 60 65

dBV

Spectra / Pz2 / SK2 / SpecReport

Drive Coast

Crank

Cam

H1 H2

H3

Various filed units shown as stray bands. The gear mesh energies are clearly seen.

Page 16: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Evaluation of Order Spectra

10 20 30 40 50 60 70 80 90 Ord

45

60

75

90

105

dBgVGW

VGW-lim

The order spectra of the synchronous channelsand of the mix channel are compared with a

limit curve. Every order of the limit curvehas an underlying error code. This error codeis generated from transmission ratios in a semiautomatic fashion. If the limit curveis exceeded, the error code gives rise to anerror message in plain text.

The limit curves consist of portions, whichare generated by a learning process and ofportions which are set to fixed values.

The learn rnode is used for those spectralportions, where there are results from driving experiments available yet. Generally thisholds true for tooth spacing problems,ghost orders and bearing noise (in themix channel).Fixed limits are adopted from driving experiments,usually for the gear mesh and for the side bands.

Page 17: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

10 20 30 40 50 60 70 80 90 Ord

20

40

60

80

100

dBg

MaxBnd

MinBnd

StdDev

AW-avg

SK1-lim

Spectral Limits

Limit curve from Average + Offset + n times standard deviation. Overridden by minimum and maximum polygons and by the fixed hats.

Hats for gear mesh orders and their side bands

Page 18: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Learning

For all measurements, the following statisticalproperties are computed:

Average (AV) undStandard deviation (STD)

From these numbers, a limit L is generatedaccording to

L = AV + Offset + n* STD.

The offset and the multiplier of the standard deviation is selectable. For spectral measures,an offset of 5 dB and a std-factor of 3 is normally used. Maximum and minimum values set upper and lower bounds for the limit L.

A new learn consist of a base learn (usually 5 units), where all units are accepted that are below maximum polygons and below hats.

The base learn is followed by an additional learning (usually 100 units). Here every unit is evaluated against the already established limitcurves. Only error free units will be added to the learning sample.

Another available choice consists of a indefinite learn process with a selectable time constant.

During the whole learning process, the fixed limits apply. This assures, that all known data (like limits from car experiments) will be used as a guidance during the process.

What is learned Learning methods

Page 19: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Intranet Statistics

The information of the SQL measurement database can be retrieved via the intranet.

The production results and the measurements can be seen online.

An arbitrary time interval can be selected for the analysis.

Page 20: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Reject Analysis, Top n and Type Specific

The results are shown both in tabular and in graphical form

Page 21: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Measurement Statistics and Bench Comparison

Over 300 individual measurement results can be evaluated.

The comparison of test benches makes it easy to administer large production facilities.

Page 22: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Order spectra of production units can be displayed in Campbell or in 3-D graphs. Cuts in the order or in the unit direction show order amplitude versus units or the spectrum of one unit. The pictures show the order spectra of 300 production units. A ghost order of 118 is present in the first 40 units tested.

Spectral Statistics

Page 23: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Cabin noise components

Noise sources

There are many different transfer paths for the sound and the vibration from the gearset to the drivers ear.

Each path has its own frequency dependent transfer function

Noise from the motor, wind and tires may mask certain frequency bands from the gears.

These effects induce the speed, torque and vehicle dependent noise perception of the gear sets.

Transfer paths

Page 24: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Order spectrograms

Order spectrograms are recorded for the gearbox vibration signal and for the cabin sound field.

From these order tracks for arbitrary orders and order spectra for arbitrary speeds can be generated:

1) Ordnungs-Spektrogramm 4. Gang Zug

Order track for the 65. order

2) Order spectrum at 2241 RPM

Page 25: RotasPro Gear Test and Noise Analysis - Discom · PDF fileRotasPro Gear Test and Noise Analysis. ... CVT Transmissions ... Graphs show one revolution of the cam gear when run as pairs

2.10.2007

Vehicle: Accelerometer at Gearbox and Sound in Cabin