Vehicle Countermeasures Against Incompatible Crashes

Stewart Wang, UMPIREPaul Weber, Breed UMPIRE Fellow

Val Bellora, Johnson Controls UMPIRE Fellow

Safety Improvement

Understand ProblemFi ld DATAField DATA

Way to EvaluateInjury Criteria

ATDTest Procedure

Design Countermeasure

EngineeringManufacturingRepeatability

Half the vehicles sold in the USA SUV li ht t kare SUVs, light trucks or vans

Vehicle IncompatibilityVehicle Incompatibility

Mass Stiffness GeometryMass, Stiffness, Geometry

Vehicle IncompatibilityWorst Case Scenario

Safety Improvement

Understand ProblemFi ld DATAField DATA

Way to EvaluateInjury Criteria

ATDTest Procedure

Design Countermeasure

EngineeringManufacturingRepeatability

LTV Front to Car Crashes (NASS 1997-2001)

R ll

(NASS 1997-2001)Frequency

FrontRear

Rollover2%

Front22%

Rear29%

Side47%

LTV Front to Car Crashes (NASS 1997-2001)(NASS 1997 2001)

Distribution of Occupants with MAIS>=3

Rear5%

Rollover2%

SideFront43%

Side50%

LTV Front to Car Crashes (NASS 1997-2001)

Rear Rollover

Distribution of Occupant Harm

Rear8%

2%

Front33%33%

Side57%57%

Test Modes/Regulations

• FMVSS 214 (Dynamic)• Roll-out began in MY 1994, applied to all passengerRoll out began in MY 1994, applied to all passenger

cars starting in MY 1997

• LINCAP

• ECE R95

• FMVSS 201FMVSS 201• Upper interior requirements: Roll-out began in MY

1999 (Free Motion Headform)D i P l t t ti f hi l ith id• Dynamic Pole test option for vehicles with side curtain airbag systems

• IIHS LTV Side Impact TestIIHS LTV Side Impact Test

ATD’s for Side ImpactATD s for Side Impact

Several ATD’s and multiple injury criteria are being used to p j y gassess lateral impact injury.

– SID (or US-SID) (FMVSS 214)

S 1– Euro-SID1 (ECER95)

– ES-2 BioSID– BioSID

– SID-IIs (IIHS test ATD)

– US-SID with the Hybrid III head and neckUS SID with the Hybrid III head and neck (LINCAP, FMVSS 201)

– World SID

Every ATD style has advantages & disadvantages in testing & bio-fidelity

FMVSS 214 Load Case

• FMVSS 214I t Di ti C b

Wheelbase (W)

940mm

Struck Vehicle0.5W

– Impact Direction:Crab– Impact Speed: 33.5 mph

Barrier Bumper is 13”

SIDS

– Barrier Bumper is 13 (330 mm) above Ground

– 2 US SIDs– Requirement:

• TTI <= 85 G

Moving DeformableBarrier

Direction of• Pelvis Acc. <= 130 G27

Direction of

Thoracic Trauma IndexThoracic Trauma Index

Thoracic Trauma Index (TTI)

TTI = ½ (GR + GLS)

GR - Greater of the peak acceleration

TTI ½ (GR GLS)

R pof either the upper or lower rib

GLS - Peak acceleration of the lower spinespine

Side Impact Dummy (SID)

LINCAP Load Case

• LINCAPImpact Direction:Crab

Wheelbase (W)

940mm

Struck Vehicle0.5W

– Impact Direction:Crab– Impact Speed: 38.5 mph– Barrier Bumper is 13” (330

SIDS

mm) above Ground– 2 US SIDs– Rating: Starsg

Moving DeformableBarrier

Direction of

5 Star TTI57

4 Star 57<TTI 72

27

Direction of3 Star 72<TTI 91

2 Star 91<TTI 98

1 Star TTI>981 Star TTI>98

Pelvis G’s noted if exceeding 130g’s

Fatal Injuries: Near-Side Occupants

FARS 1993 1999 Model Years 1994 19991 0

FARS 1993-1999, Model Years 1994-1999

ed

6

8

on R

egis

tere

4

6

ity p

er M

illio

ehic

le Y

ears

2

cupa

nt F

atal

iVe

0

I mp a c t b y

C a r

L e s s T h a n

I mp a c t b y

C a r

3 5 0 0 lb s o r

I mp a c t b y

L ig h t T r u c k

L e s s T ha n

I mp a c t b y

L ig h t T r u c k

3 5 0 0 lb s o r

Occ

3 5 0 0 lb s . H e a v ie r 3 5 0 0 lbs . H e a v ie r

P r e - F M V SS2 1 4 D C a r s P o s t - F M V SS2 1 4 D c a r s L i g h t T r u c k s

Fatal/Major Injuries: Near-Side Occupants

Five States (AL FL ID MD NC) 1994 1999Five States (AL, FL, ID, MD, NC) 1994-1999, Model Years 1994-1999

250

200

per M

illio

n

100

150

al o

r Maj

or In

jury

ed

Veh

icle

Yea

rs

50

100

upan

ts w

ith F

ata

Reg

iste

red

0

Occ

u

Impact byCar

Less Than

Impact byCar

3500 lbs or

Impact byLight TruckLess Than

Impact byLight Truck3500 lbs orLess Than

3500 lbs.3500 lbs orHeavier

Less Than3500 lbs.

3500 lbs orHeavier

Pre-FMVSS214D Cars Post-FMVSS214D Cars Light Trucks

Velocity Time History – FMVSS 214 Side Impact Test (Mid-size Sedan)

Side Impact Energy Management

Body Side StructureDOORB

A

Utilize structural load paths to re-direct the energy

STRU

ARRIE

CTURE

R

Manage the energyEAE

Door Structure

Body Side Structurey

C iC-PillarB-PillarA-Pillar

RockerFront Body Lock PillarHinge Pillar

Lock Pillar

Passive Countermeasures (CM)

Safety Improvement

Understand ProblemFi ld DATAField DATA

Way to EvaluateInjury Criteria

ATDTest Procedure

Design Countermeasure

EngineeringManufacturingRepeatability

The Problem for Interior:• Occupant is ACCELERATED by application of FORCE• Contact from Vehicle, Tree, Door or Header

Understanding the Problem - Doors

• Example of low application of force through door.• Hips are accelerated first followed by the shoulders.• Application of force to abdomen through armrest is not desired• Application of force to abdomen through armrest is not desired.

Passive side impactPassive side impact Countermeasures - Door

FMVSS201 Requirements

• Free Motion Headform (FMH)• 10 lb• 10 lb• 15 mph• HIC number calculated from

AccelerationAcceleration.• Phase-in (MY 1999-2002) will be

complete by 2003

Formula from FMVSS201

t 5.2

2

restt ttdtaHIC

12)(

12

12

Maximumt

1

Average Acceleration Duration

•Regulation HIC below 1000•Regulation HIC below 1000•Target HIC below 800

FMH Impact Locations

Theoretical Relations• We analyzed mathematically what drives the HIC number so that we could understand how to lower the

number. We also studied the theoretical responses of various acceleration waveforms.

HIC for Haversine Wave (8 ms Duration)V i ATC ith 800 HIC(d)

1000

HIC for Haversine Wave (8 ms Duration)

800-1000

Various ATC with 800 HIC(d)

75

100

125

150

175

200

cele

ratio

n (g

's)

RectangleTriangleHaversine

Trapezoid

400

600

800

1000

HIC

600-800

400-600

200-400

0

25

50

0 1 2 3 4 5 6 7 8 9 10

Time (ms)

Acc

4 87.2

.85.66.

47.2

8

0

200 0-200Various FDC with 800 HIC(d)

4

5

6

7

8

9

orce

(kN

)

RectangleTriangleHaversineTrapezoid

02.4

4.8

00.81.

62.43.

2

44.

t2 (ms)t1 (ms)0

1

2

3

0 5 10 15 20 25 30 35

Displacement (mm)

Fo

Space is Required

35

40 Ideal Rectangular Wave with No Rebound Ideal Rectangular Wave with 1 m/s ReboundAverage of Actual Vehicle Testing

25

30

on (m

m)

g g

Inefficient Zone

ign

Zone

20

25

Def

lect

io

Desired Zone

Des

i

Mass

Mass

SystemDeflection(32 mm)

10

15 Impossible Zone FMH CM Steel

Mass

700 800 900 1000 1100 1200 1300 1400HIC(d)

Force vs. Deflection CurvesEnergy Absorbers

2500

12FM20 (793) (950) 62FMO (940) 63FMO

Flat plate, Infinite background @ 13.5 mph

2000

1000

1500

Forc

e (lb

f)

500

00 0.2 0.4 0.6 0.8 1 1.2

Displacement (in)

Pillar Countermeasures

Countermeasure Materials

Case History 1: No Countermeasure

• 1998 Caravan• Object: 2000

Taurus• PDOF: 270• 13 mph delta Vp• 68 yo Male• Restrained• 172 lb 5’ 10”• 172 lb, 5’ 10”

(50%)

Case History 1: No Countermeasure

Impact

Interior Surfaces

CONTACT

Head & Neck Injuries

•Medical data has been removed to protect patient confidentiality

Case History 2

• 1999 Intrepid• Object: Tree

PDOF 290• PDOF: 290• 15 mph delta V• 36 yo Male• Restrained• 165 lb, 6’ 2”• 26 cm @ sill26 cm @ sill• 56 cm @ roof

Damage

Damage

Significant Injuries

• Medical data has been removed to protect patient confidentiality

Head Contact

Contact

Side Impact Air Bag Countermeasures

• This section will focus on development of inflatable technology and addressing what inflatable restraintstechnology, and addressing what inflatable restraints can do to offer “self -protection” in lateral “incompatible” crashes.

Side Air Bag EvolutionSide Air Bag EvolutionSide Air Bag EvolutionSide Air Bag EvolutionMY ’95 MY ’96 MY ’97 MY ’98 MY ’99-00 MY ’01-02 MY ’03 MY ’04

• Thorax System• 214 / 95 Requirements• Europe Leading

(Volvo Mercedes)

• Head/Thorax System• Due Care

(Pole High Hood)• Curtain / Thorax • Low Risk OOP • Rollover

5 7 h ld ti

• Curtain + Pelvic/ Thorax • Low Risk OOP

(Volvo, Mercedes) 5-7sec hold time

• Thorax System• U.S. Following• Due Care Considerations

• Head/Thorax System• Tuned Inflator

• ITS• Europe (BMW)

• Thorax/Pelvis Bag

Field Data

• To date, relatively little field crash experience is available with inflatable lateral protection devices. Th d t th t i il bl d t i i l h i• The data that is available does suggest minimal harm is being induced in field, and there is limited evidence of at least some benefits from lateral inflatables.

What does an airbag do?

Frontal:The occupant is effectively accelerating towards Steering Wheel / IP as

vehicle is deceleratingThe frontal airbag:• Offers increased loading area• Energy Absorbing (transfers KE into Work through vent holes or

fabric) => gradual decelerationfabric) => gradual deceleration• Prevents hard contacts with wheel, IP, Windshield, Pillars

Lateral:Lateral:The vehicle is effectively accelerating towards occupantThe airbag:• Prevents hard contacts between head & barrier/pole• Offers stability for Head / Neck / Shoulder complex• Reduces acceleration for Thorax / Abdomen/ Pelvic complex

Frontal and lateral airbags operate differently in how they mitigate injury

Side Impact Air Bag ConsiderationsConsiderations

Additional Considerations for side vs frontal airbags:

4 there is little vehicle crush space to accelerate the occupant compartment before occupant loading.

44 The occupant is impacted by the striking object with a portion of his vehicle side structure around it.

4 The location of a side impact relative to the occupant has a major effect on the p p jseverity of the crash as seen by the occupant

Vinitial

striking

Narrow “Crush zone”

striking

Vbetween occupant and vehicle

Voccupant

Lateral Airbag SystemDesign Iteration/Balance

Static Out ofOut of

Position

In-position

Packaging Constraints

AIRBAG DESIGN p

DynamicCYCLE

Establish Coverage

for OccupantOccupant

Sizes

Example of Side Airbag ModuleExample of Side Airbag Module

Side Airbag Module:

Inflator:• Hybrid BREED HSI-140

Cushion:• 11 litre single chamber rollfold• ventholes according to performance• 700 dtex fabric uncoated with reinforcement and heatshíelds

Housing:• single injection TPEE (Multiflex)• single injection TPEE (Multiflex)• colour black

Cover:• single injection TPEE (Multiflex), grained A-surface unpainted• colours:

• natural (Lancia 839 invisible)• black (Alfa 932 / Fiat 244 visible)black (Alfa 932 / Fiat 244 visible)• grey (ALFA 932 visible)• leather covered (blue / red / beige) (Alfa 932 visible)

• opening by tearing 4 pins (ultrasonic welded)

Curtain Airbag ModuleSide Airbag Module Curtain Airbag (Product Description)Description)

oof R

ail-A

B M

odul

(CAD

)

oof R

ail-A

B M

odul

(Det

ail)

Curtain Airbag Module:

Inflator:• Inflator Cold gas• Filling 100%He

Module Concept:

• Deployment zone between A and C / D pillar.

• Maximum mass approx 1600 gr

Ro Ro

• Filling - 100%He• Pressure - 600bar• Gas filling weight adjustable

Rollover Cushion:• Silicone coated, 470dtex, PA 6.6.• Volume 30-35 ltr.• Sewn bag design liquid silicone

• Maximum mass approx. 1600 gr• Manifold: steel tube• Filltime max 25ms @-30°C

Standard Cushion:• Uncoated 470dtex PA 6.6.• Volume 30-35 ltr.• Sewn bag design • Sewn bag design, liquid silicone

sealing or OPW coated or STC

Cover:• soft pack (pocket)

• Sewn bag design,

3 year old HIII Seating Position in Mid-Sized Sedan

6 year old HIII Seating Position in Mid-Sized Sedan

5th%ile (SID-IIs) Seating Position in Mid-Sized Sedan

50th% (EuroSID) Seating Position in Mid-Sized Sedan

Mid-Seat Euro-SID

▶ Coverage Zone Concept

“A-C” Pillar Protection Coverage

Full ForwardSID-IIs Rear Euro-SID

Static Out of Position

• A Technical Work Group (TWG) - IIHS, Alliance, AIAM, AORC, Transport Canada - has developed voluntary OOP procedures and injury targets for:

4SID-IIs (5th%ile HIII) w/ instrumented arm4Hybrid III, 6 year old sized44Hybrid III, 3 year old sized

• Evaluations vary by type of side impact air bag.4Door mounted4Seat mounted4Roof rail mounted curtains and inflatable tubular structures

Out Of Position Test Configurations7 static positions to assess SAB OOP performance.

3.3.2.1/5 Forward-3.3.2.1/5 Forwardfacing 3Y & 6Y HIII

3.3.2.2 Rearward facing

3Y ld HIII3Y old HIII

3.3.2.3 Lying on seat, head on

3year old 6year old

,armrest 3Y HIII

3.3.2.4 Lying on seat 3Y HIII

3.3.2.6 Inboard facing SIDIIs

3.3.2.7 SIDIIs with instrumented arm

TWG injury values Reference values

Hybrid III3-Yr Old

HEAD

Hybrid III6-Yr Old

Hybrid IIISm. Fem.

SID IIs

HEAD570 723 779 779

UPPER NECK

15ms HIC

UPPER NECK

Nij(Ft/Fc/Mf/Me )

1 1 1 12120/2120/68/27 2800/2800/93/37 3880/3880/55/61 3880/3880/155/61

Tension (N)Comp. (N)

THORAX

20702520

1130 1490 20701380 1820 2520

Defl. (mm)Defl. Rate (m/s)

THORAX

36 40 ——

348.0 8.5 8.2

Side Impact Air Bag Ch llChallenges

• Crash sensing:4Distinguishing the various side impact events (pole, car, truck) in time

fi h l l i b d i i i i i fto fire the lateral airbag, and maintaining immunity from non-severe events (door-slam, ball-hit, bicycle etc.)

44 In general, lateral airbags need to begin deploy about 4 - 8 msec after initial contact . This is about 1/3rd the time: to sense the crash, process the algorithm, and initiate a fire-command , as compared to frontal impact air bagsimpact air bags.

4Thorax cushion requires about ~ 10msec to fill4C t i Ai b i b t 25 t fill4Curtain Airbags require about ~ 25 msec to fill.

Side Impact Air Bag Ch llChallenges

• Thorax bags must deploy in gap between seat bolster and door trim, and occupant.door trim, and occupant. 4Gap is small on small cars4Occupant size can affect deployment

• Curtain airbags must deploy over the B- pillar trim, belts, and often over rapidly deforming sheet metal.and often over rapidly deforming sheet metal.4There is often opportunity for Curtain to interact negatively with

structure

Packaging: Decreased packaging volume due to f t i i th f ilpresence of curtain in the roofrail area

increases the challenge of meeting FMVSS 201 type head impacts

FMVSS 214 Barrier vs IIHS LTV Barrier Height

IIHS LTV

FMVSS 214

Comparison of IIHS High Hood and Regulatory Testsg y

Description IIHS High Hood FMVSS 214 ECE R95I t A l 90 d 63 d 90 D

Side Impact Crash Test Configurations

Impact Angle 90 degrees 63 degrees 90 DegreesBullet Weight 1,500 kg 1367 kg 950 kg

Bullet Speed 50 kph54 kph in 63 deg. Direction(or 48 kph lat./ 24 kph long.) 50 kph

Front edge of barrier face Middle plane of barrier face in lineImpact Location 300 mm rear of FMVSS 214

Front edge of barrier face@940 mm from half wheelbase plane

Middle plane of barrier face in linewith front row SRP

Barrier Face Size 762 mm H x 1,676 mm W withtapered on both side edges 559 mm H x 1,676 mm W 500 mm H x 1,500 mm W

Ground Clearance 381 mm 279 mm 300 mmGround Clearance 381 mm 279 mm 300 mm

Seating Position UMTRI positionDesigned seatback angle

Mid- seat travel lowest seat cushion.

Designed torso angle (25 ifunknown) , mid seat travel,same heightas non-adjustable, or mid height.

Dummy SIDIIs front and rear US SID front and rear EuroSID front only

Because IIHS LTV crash test specifies heavier barrier mass and higher d l th FMVSS 214 th i j l

Dummy SIDIIs front and rear US SID front and rear EuroSID front only

ground clearance than FMVSS 214, the injury values are more severe.

Regulations / T t M dTest Modes

From the inflatable restraint viewpoint, the IIHSFrom the inflatable restraint viewpoint, the IIHS test protocol is the primary method to assess & improve “self-protection” for “incompatible” lateral crash modes.

The IIHS LTV (incompatibility) test modehas several additional challengeshas several additional challenges

for “Self - Protection” injury mitigation:

• Likely head-to-barrier contact requires inflatable head protection:4Curtain or Head cushions

Hi h ATD l d Th / Abd / P l i (th ith LINCAP)• Higher ATD loads on Thorax / Abdomen / Pelvis (than with LINCAP)4 Improved door padding4 Structural stiffness4 Increased Airbag pressures and/or hold times in order to offer some c eased bag p essu es a d/o o d t es o de to o e so e

protection for thorax / abdomen / pelvis.

• Sensor Fire time:4 Current sensor are either acceleration or pressure based4 Current sensor are either acceleration or pressure based4 Current sensor are typically located at bottom of B- (and C-) pillar / rocker

panel

Un-deformed B-pillar

Transport Canada, 2002

Comparison of IIHS High Hood vs.US SINCAP Door Motion

An Example of Generic Mid-Sized Sedan IIHS High Hood Full Scale vs. TestDoor at Belt Line Velocity Pulse

14

12

IIHS High Hood

8

10

y (m

/s)

4

6Vel

ocity

US SINCAP

2

IIHS High Hood test is much more severe when compared toUS SINCAP in the speed of intrusion (thus intrusion amount) and slightly worse in initial intrusion during which side airbag is being fired.

00 10 20 30 40 50 60 70 80 90 100

Time (ms)

IIHS High Hood Barrier Ford Focus

SAB vs. No SAB

200%

250%

100%

150%

% IA

RV

No SABSAB

50%

100%

0%

HIC15

ck Ten

sion (

kN)

X mom

ent (N

m)x Rib

defl.

(mm)

b defl.

rate (

m/s)ax

Rib

V*C (m

/s)mina

l defl

. (mm)

alde

fl. rat

e (m/s)

minal V

*C (m

/s)Pub

ic for

ce (k

N)Ilia

c forc

e (kN

)bu

lum fo

rce (k

N)

Nec

Neck X Max

Max R

ib MaxMax

. Abd

omMax

. Abd

omina

l Max

. Abd

om P

Acetab

u

Side Air Bag EvolutionSide Air Bag EvolutionSide Air Bag EvolutionSide Air Bag EvolutionMY ’95 MY ’96 MY ’97 MY ’98 MY ’99-00 MY ’01-02 MY ’03 MY ’04

• Thorax System• 214 / 95 Requirements• Europe Leading

(Volvo Mercedes)

• Head/Thorax System• Due Care

(Pole High Hood)• Curtain / Thorax • Low Risk OOP • Rollover

5 7 h ld ti

• Curtain + Pelvic/ Thorax • Low Risk OOP

(Volvo, Mercedes) 5-7sec hold time

• Thorax System• U.S. Following• Due Care Considerations

• Head/Thorax System• Tuned Inflator Future (MY 06+)

• ITS• Europe (BMW)

• Thorax/Pelvis Bag Designs for IIHS LTV,“new” FMVSS 214

Safety Improvement

Understand ProblemFi ld DATAField DATA

Way to EvaluateInjury Criteria

ATDTest Procedure

Design Countermeasure

EngineeringManufacturingRepeatability