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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Automatic Transmission Modeling for Shift Quality using Adams/Driveline

Paul Erlandson & Jack S. P. LiuFord Motor Company

Livonia, Michigan(734) 523-5484

Abstract: This paper introduces the use of Adams/Driveline to create a more streamlined approach to full-vehicle modeling for shift quality and transient NVH.

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Presentation Outline

Why Adams/Driveline for Automatic Transmission?

Key Adams/Driveline Features

Typical Adams/Driveline Automatic Transmission Model

Exporting to Adams/Chassis

Sample analysis for shift quality

Conclusions

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Why Adams/Driveline ?

Template-based. Seamless integration of transmission and driveline models.Quicker time to integrate trans/driveline assembly with vehicle model (compared to previous A/View-based method).“Re-integration” is sometimes necessary!Bottom line: Turnaround time to produce integrated Vehicle/Transmission model is reduced by > 70% !

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Key A/Driveline FeaturesConceptual Wet ClutchTorque ConverterPlanetary GearsetRavigneaux Gearset

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Conceptual Wet ClutchAllows relative slip when torque capacity is exceeded.“Locks” when torque demand is less than torque capacity.Torque capacity is calculated from parameters in the clutch property file.Open clutch drag can be modeled.Timing of clutch element is handled via spline data in the clutch property file.

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Conceptual Wet Clutch

Clutch Torque (SFORCE)RoRi

D

dFp

Clamping force:

Piston force:

APF ss =

4)(

)()(2

paap

DtpAtPtF

π==

spc FtFtF −= )()(

Spring preload:

2io

mRR

R+

=

Effective radius:

(s)NRstFtT cmcc sgn)()()( µ=

-1

0.20

-0.2

1

sgn(s)

s

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Conceptual Wet Clutch (property file)

$------------ CLUTCH_DATA

[CLUTCH_DATA]

N_OF_SURFACE = 10 (Nc)

EFFECTIVE_RADIUS = 58.67 (Rm)

PRESSURE_AREA = 11755 (A)

TURNING_POINT_PRESSURE = 0.0 (Ps)

CLUTCH_MU = 0.11 (µ)

OPEN_CLUTCH_DRAG_GAIN_FACTOR=0

TIME_OFFSET = 0

$----------- CLUTCH_PRESSURE[CLUTCH_PRESSURE]{ time pressure}-5.0 500.0-2.0 500.0-1.0 500.00.0 500.01.0 500.03.2 500.05.0 400.08.5 300.08.7 0.010.0 0.020.0 0.0

Clutch Pressure Spline (Pa)

0

100

200

300

400

500

600

-5 -2 -1 0 1 3.2 5 8.5 8.7 10 20

Time (sec)

Pres

sure

(psi

)

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Torque Converter

Models torque multiplication of the converter.

Relates turbine speed and torque to impeller speed and torque.

Uses standard converter performance tables, stored in the property file.

Lockup Clutch Modeling.

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Torque Converter

Engine Torque (SFORCE)

)1,01.1,1,99.0,(2 −= r

ri

ii SSTEP)

)(sK(t)N((t)T

1

-1

0sr

)1,01.1,1,99.0,( −rSSTEP

1

FUNCTION = AKISPL (time, 0, id)

Torque Converter:Impeller Drag (Impeller-Turbine)

Ni(t) = engine rpmKi(sr) = capacity factor (K-curve)rt(sr) = torque ratio curve

Turbine Torque (Turbine - Case)

)()1)(()( tTsrtT irto −=

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Torque Converter

Lockup Clutch (SFORCE)

Tp (t) = Tp(t) sgn(s) STEP(sr , s1-,0, s1

+,1)

•

−−= θθ CKTd

Spring-damper Assembly (SFORCE)

-1

0.20

-0.2

1

sgn(s)

s

1

0sr

s1

STEP(sr , s1-,0, s1

+,1)

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Torque Converter (property file)

$-------TORQUE_RATIO{speed_ratio torque_ratio}0.0 1.90.1 1.80.25 1.70.4 1.60.5 1.50.6 1.40.7 1.30.8 1.10.9 0.99

$--- CAPACITY_FACTOR{speed_ratio capacity_factor}0 176.00.1 174.00.2 174.00.3 175.00.4 176.00.5 183.50.6 191.40.7 200.40.8 218.10.9 272.5

Torque Converter K Curves

150

175

200

225

250

275

0 0.5 1 1.5Speed Ratio (Sr)

K-fa

ctor

@M

p200

0176K

Torque Ratio Curves

0.0

0.5

1.0

1.5

2.0

0 0.5 1 1.5 2Speed Ratio (Sr)

Torq

ue R

atio

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Planetary Gear Set

Kinematic coupling between Sun, Carrier, and Ring parts.

Uses Adams COUPLER statement, based upon tooth number for each element.

Planetary set backlash is modeled through use of a “dummy” sun and “dummy” ring part.

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Planetary Gear Set

0332211 =++ qqq λλλPlanetary gear set: (3-way Coupler)

S

R

P

C

Where λ1, λ2, λ3 are related to the tooth numbers of sun (S) and ring (R) gears

RandRSS =+−== 321 )(, λλλ

Gear Lash: (Rotational SFORCE)

0θθ0

•

−−= Te

Tl CKT

FUNCTION = BISTOP (AZ (I, J), WZ (I, J, R), θ1, θ2, KT, e, CT, d)

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Ravigneax Gear SetKinematic coupling between Sun, Carrier, and Ring parts.Similar to Planetary Gearset element.

Sun Gear 2

Long Pinion

Short Pinion

Sun Gear 1

Common Ring Gear

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Typical A/Driveline Automatic Transmission Model

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Typical A/Driveline AWD Driveline Model

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Assembled Transmission and Driveline Model

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Exporting to Adams/Chassis

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Integration in Adams/Chassis

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Sample Analysis for Shift Quality

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MSC.Software VPD Conference | July 17-19, 2006 | Huntington Beach, California

Conclusions

Transmission-specific elements in Adams/Driveline make auto trans model creation easier.

Seamless integration with driveline subsystems.

Export to Adams/Chassis speeds up creation of vehicle/transmission model.

Bottom line: Same great results as with our previous Adams/View-based method, but in less time. Internal customers get results more quickly!