Vechile Dynamics Simulation

of a Racing Car by NISMO of a Racing Car by NISMO

Nissan Motorsports International Co.,Ltd.

Yasuharu Kamei

Toshiyuki Takahashi

Contents

• NISMO and Racing activities

• Transition/History of Circuit simulation

• Case study with “VI-Sports Car”

• The advanced simulation technology for • The advanced simulation technology for

vehicle dynamics performance

• Summary

NISMO and Racing activities

Why does NISMO participate in or support various domestic and international races?

Contribution to establishment of Nissan Brand Identity

NISMO is a subsidiary of Nissan Motor Co., Ltd. of motorsports business. Its main business activities are to design and sell motorsport vehicles as well as its parts, and to manage domestic and international racing promotional activities. NISMO actively participates in or supports various domestic as well as international races.

NISMO and Racing activitiesFIA GT1

NISMO participates in FIA GT1 which is an ideal racing category as a constructor and provides GT-R to SUMO POWER GT and SWISS RACING TEAM

2010 Series(Total 10 Race/7 races finished）SUMO POWER GT ⇒ Point Ranking 3rd (Rd.2 Winner））））SWISS RACING ⇒ Point Ranking 11th

#22, #23

NISMO and Racing activities

FIA GT1

LengthWidthWheel baseWeightENG Max. PowerENG Max. TorqueSuspension Type

4730 mm2040 mm2780 mm1250 kg （Y2010 Formulation）600 ps650 Nm overDouble Wishborn(Front)

Providing racing cars and introducing the high level technology of Nissan

#22, #23 SUMO POWER GT

#3, #4SWISS RACING TEAM

Suspension Type

Tire Size

Double Wishborn(Front)Multi Link(Rear)31/71-1831/71-18

NISMO and Racing activities

SUPER GTParticipated in SUPER GT GT500 class as a works teamAcquired many wins and podiums in 2008 series with new GT-R

’08 Series(9 races)#22, #23 :Qualification 1st/4time 2nd/twice

Result 1st /3times 2nd /twice �Series Champion’09 Series(9 races)

#1 : Qualification 1st/3timesResult 1st/twice 2nd/once � Point Ranking 3rd Rd4 SepangResult 1st/twice 2nd/once � Point Ranking 3rd

’10 Series(8 races/6races finished)#23 : Qualification 1st/once 2nd/once

Result 2nd/twice � Point Ranking 6th

Rd1 Okayama

Rd2 Rd6 Suzuka

Rd3 Rd7 Fuji

Rd8 Motegi

Rd5 Sugo

Rd4 Sepang

2

3

前後

+横方

向 加

速ベクトルの

大きさ [G]

G Tカー

市販車

高G走行

NISMO and Racing activities

GT-R GT500

4695 mm2000 mm

Maximize the vehicle ability of “accelerating, cornering and braking”

High Performance of GT-R

LengthWidth

・GT-R・Commercial GT-R

The

Nor

m o

f lon

. and

lat.

Acc

.(G

)

High G

0

1

0 100 200 300

車速 [km /h]

前後

+横方

向 加

速ベクトルの

大きさ [G]

高速走行

High potential GT car is developed by Nismo’s effort

2000 mm2720 mm1100 kg450 ps over48 Kgm overDouble Wishborn330/40R18330/45R17

WidthWheel baseWeightENG Max. PowerENG Max. TorqueSuspension TypeTire Size

Speed (km/h)

The

Nor

m o

f lon

. and

lat.

Acc

.(G

)

High Speed

Transition/History of Circuit Simulation

Issues

1. Short Development Period

2.Limitation of the circuit test

Development of GT Car and Vehicle Dynamics Simulation

Using simulation technology is very efficient to solve the multiple problem of special GT Car development Design

Vehicle Dynamics Simulation

8

2.Limitation of the circuit test

Nismo is focusing on technical improvement of vehicle performance simulation to achieve a higher performance of GT car.

Adopting and utilizing simulation technology in order to smoothly pursue the development cycle of design and tests.

Counter Plan

3.Changing of preconditions for study

Test

Simulation

Transition/History of Circuit Simulation

Transition/History of Circuit Simulation in Nismo

1990199019901990 2000200020002000 2010201020102010

Quasi-static

Circuit Simulation

Circuit simulation is very important part in vehicle dynamics simulation to pursue the vehicle maximum performance

9

Quasi-staticLinear

Quasi-staticNon-linear

Dynamics including transient behaviorNon-Linear

VI-SportsCar including detailed component and driver model

<Input>Vehicle Spec.EngineAerodynamicsSupension・Tire

Lap TimeSpeedLon./Lat. Acc.・・・・

<Output>

<Input>Vehicle Spec.Engine(Non-linear)AerodynamicsSuspensionTire(Non-linear)

<Output>Lap TimeSpeedLon./Lat. Acc.Engine RpmThrottle Open・・・

Transition/History of Circuit SimulationVI-SportsCar Overview

・Non-linear characteristics of component for a racing car・Transient Behavior including a driver input・Reaction force which is applied to each component

Laptime simulation software by VI-gradeDetailed vehicle model based on MSC.AdamsTM

Maximized the vehicle performance using virtual vehicle and circuit

<Input>Vehicle Spec.

<Output>LaptimeVehicle Spec.

EngineAerodynamicsSuspension Char.Braking Char.Steering Char.TireDriver Model �

Most of components are specified by non-linear characteristics.

LaptimeSpeedLon./Lat. Acc.Yaw RateVehicle PathTire ForceTire StatePosture TransitionSWABrake ForceReaction force at suspension, damper and spring mount・・・・

Case study with VI-SportsCarCase Study1

Lap Time Fast

Testing an actual car is required enormous amount of time for the development process, such as building prototype parts, preparing for tests and

Simulation Case Study)Laptime study beteen vehicle wieght balance and downforce balance

Investigating the influence of the vehicle setting parameters for unit characteristics within short timeframe.

Lap Time Slow

prototype parts, preparing for tests and others.

Utilizing the VI-SporsCar dramatically upgrade the efficiency of development process.

Case Study 2

Case study with VI-SportsCar

Extracting the vehicle states that are difficult to measure from an actual car and comparing the influence of these parameters in VI-SportsCar.

Difficulty of comparison of vehicle performance between difference settings in a actual car.-- Case of Body Stiffness by stiffening --•Measurement noise is so big and comparison of time axis is misleading and confusing.•Measurement noise is so big and comparison of time axis is misleading and confusing.•Almost impossible to have exactly the same condition of climate, road condition and tire wear and others.•it is impossible to measure the performance tradeoff between rigidity improvement and weight increase

Temperature of tire, Wear, Fuel Mass Transition

Case study with VI-SportsCar

Simulation Case Study)Body Stiffness vs Yaw Acceleration under the same steering wheel input.

The body stiffness effect of yaw accelerationincreasedecrease

Simulating the complex problem which is effected by multiple parameters.The simulation can extract the slight changes by just changing and reviewing the focused settings in simulation.

Case Study 2

Steering Wheel Angle

Ste

erin

g W

heel

Om

ega

Possible to review the complex phenomenon in real world using the vehicle dynamics simulation.

Increasing of the yaw acceleration under the same condition because of the body stiffness.

↓Difficult for a actual car to change only stiffness.

The advanced simulation technology for

vehicle dynamics

1) Applying the optimized automatic calculation algorithm

A number of parameters which affect laptimeCombination of component characteristics

Problem• Huge number of parameters for simulation model.• Needs enormous time to run the parameter study manually and find out the best design.

Component A

A A A A ---- 1111

A A A A ---- 2222

A A A A ---- 3333

A A A A ---- aaaa

・・・

Component B

B B B B ---- 1111

B B B B ---- 2222

B B B B ---- 3333

B B B B ---- bbbb

・・・

Component C

C C C C ---- 1111

C C C C ---- 2222

C C C C ---- 3333

C C C C ---- cccc

・・・

Combination of component characteristics

Ex.)Huge time to run all combination manually.Unreasonable system(manual running) under the development process of the racing car.

・・・

・・・

・・・

・・・

・・・

Automatic running system is required to speed up

The advanced simulation technology for

vehicle dynamics

1) Applying the optimized automatic calculation algorithm

Design parameters and characteristics which are defined by user⇒ Automatic Running

Multi objective optimization algorithm for circuit simulation

1. Extracting the component sensitive to lap time.2. Extracting the characteristic bands sensitive to laptime.3. Finding out the best design for the fastest lap.

VI-CarRealTime

Component A

A A A A ---- 1111

A A A A ---- 2222

A A A A ---- 3333

A A A A ---- aaaa

・・・

Component B

B B B B ---- 1111

B B B B ---- 2222

B B B B ---- 3333

B B B B ---- bbbb

・・・

Component C

C C C C ---- 1111

C C C C ---- 2222

C C C C ---- 3333

C C C C ---- cccc

・・・

Component D

D D D D ---- 1111

D D D D ---- 2222

D D D D ---- 3333

D D D D ---- dddd

・・・

Component E

E E E E ---- 1111

E E E E ---- 2222

E E E E ---- 3333

E E E E ---- eeee

・・・

・・・・

・・・・

・・・・

・・・・

・・・・

Ex.)

3. Finding out the best design for the fastest lap.

The advanced simulation technology for

vehicle dynamics

• Momentarily sensing or recognizing the occurring vehicle motion changes, make a judgment, and then feedback the data to be input.• Optimizing the stability and maximum performance of GT car.

To represent a human professional

Representing a professional driver who drives GT car.

sense

2) Driver Model

16

To represent a human professional driver

・・・・Response Speed・・・・Max. Steering Wheel Omega・・・・Stability・・・・Coupling Control

・・・・・・・・

NISMO aims to develop the modeling of the driver- machine interface at its maximum running capability and also to perform the vehicle dynamics simulation in higher dimension.

sense

judge

drive

Vehicle Behavior

Summary

Advantage• Investigating component effects in short time• Easy to measure any vehicle states• Sensing the slight difference change of parameters• Parameter study using huge number of design and characteristics parameters

Future Technology

• Accuracy of the absolute value(Laptime)• Rolling over a kerb and response to irregularity of road• Representing human driver effect

The simulation is efficient tool for the relative changes between combination of component characteristics. And the correlation with the testing is required to estimate the absolute value of the simulation results.

Thank you