1 Frontal Accident Research Data in Japan Frontal Accident Research Data in Japan JASIC 29 January 2014

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Frontal Accident Research Frontal Accident Research Data in JapanData in Japan 　　

JASIC29 January 2014

Purpose

• To use the AF05 dummy in the passenger seat for the full frontal impact test was agreed at IWG.

• The criteria for the AF05 dummy’s chest deflection are not agreed yet.

• To confirm the validity of the criteria of the AF05 dummy’s chest deflection, we conducted research on frontal crash accidents in Japan.

Data

• Five years of macro data from 2007 to 2011 were obtained from ITARDA (Institute for Traffic Accident Research and DATA Analysis).

• In the accident, the front area of the vehicle was deformed (vehicle to vehicle crash, and single crash)

• The occupants were fastened by the seatbelts.• The vehicles were equipped with airbags.• Multiple-impact accidents were excluded.

Age and Sex

Male 18-64 Male over 65Female 18-64 Female over 65

0% 20% 40% 60% 80% 100%

Minor

Serious

Fatal

0% 20% 40% 60% 80% 100%

Minor

Serious

Fatal


Driver Passenger

• 76% of the fatalities in the passenger seat were females.• 52% of the fatalities in the passenger seat were females over 65

years old.• It is very important to prevent elderly female passengers from

fatal and serious-injury accidents.

* Fatal : within 24 hours after the crash * Serious : visiting a hospital for at least a month

Definition of Quasi-ΔV

Quasi-ΔV1 = V1 - (M1 V1 + M2 V2) / (M1 + M2)

V: travel speed

ΔV is about 70-80% of quasi-ΔV.

Conversion-ΔV = 0.8 Quasi-ΔV

V1 V2

M1M2

0%

5%10%

15%

20%

25%30%

35%

40%45%

～30 30～40Quasi-ΔV (km/h)

40～50 50～60 60～70 70～80 80～

～24 24～32Conversion-ΔV (km/h)

32～40 40～48 48～56 56～64 64～

Ratio

in fa

tal a

nd

seri

ous

inju

red

acci

dent

Ratio of the Most Injured Body Region in Fatal and Serious-Injury Accidents per Quasi-ΔV

• In fatal and serious-injury accidents whose ΔV were below the regulatory level, the head-injury cases accounted for 5.5% and chest-injury cases for 38.7%. Therefore, the ratio of chest injuries is seven times higher than head injuries.

• It is very important to reduce chest-injury serious accidents and fatal accidents.

ΔV of Regulation Level Head/Face Chest Abdomen

0%5%

10%15%20%25%30%35%40%45%

Quasi-ΔV (km/h)～60

～48Conversion-ΔV (km/h)

Ratio

in fa

tal a

nd

serio

us in

jure

d ac

cide

nt

Ways of Reducing the Number of Chest-Injured Elderly Occupants

• Reduce the force level of the seat belt force limiter.

• Control the airbags (power, shape and so on). ⇒ These reduce the number of chest- injured occupants (elderly and young, male and female) in fatal and serious-injury accidents at speeds below the speed limit.

Summary• This research shows it is very important to prevent elderly

female passengers from fatal and serious-injury accidents.

• In fatal or serious-injury frontal accidents at speeds below the speed limit, head-injury passengers accounted for 5.5%, the chest for 38.7% and the abdomen for 7.9%. Thus, reduction of chest-injury accidents is more important than those of other body regions.

• Therefore, it is valid to use the AF05 dummy in the passenger seat, and to determine the thorax injury criteria based on the risk of injury to elderly occupants.

Supplement• There is a concern that the use of a female dummy with a different seat belt load

might cause a male occupant to dash against the dashboard in a secondary collision. However, we find it appropriate to use an elderly female dummy and focus on preventing accidents among this age gender group, because the increase in the number of deaths by such a secondary collision is unclear, and the number of injuries in the head, presumably the most probable damage area in such a secondary collision, is 16% of the number of injuries in the chest (14% if within the speed limit), and hence we can expect more effect among this group than others.

• To eliminate the above concern, it will also be possible to continue testing a male dummy in parallel with the female dummy and explore solutions with airbags, etc. However, considering that we are using a male dummy in the passenger seat in the offset collision test and that the effect of conducting a dual full-lap test with both female and male dummies is unclear, further examination will be necessary before determining whether or not to add a male dummy test.

AppendixAppendix

0

20

40

60

80

100

120

140

Num

ber o

f fat

aliti

es a

nd s

erio

us in

jure

d


40～50 50～60 60～70 70～80 80～

～24 24～32 32～40 40～48 48～56 56～64 64～Conversion-ΔV (km/h)

• In fatal and serious-injury accidents whose ΔV were below than the regulatory level, the number of head-injury cases was 52, chest-injury cases was 363 and abdomen-injury cases was 74 (five years).

• In fatal and serious-injury accidents whose ΔV were over the regulatory level, the number of head-injury cases was 17, chest-injury cases was 60 and abdomen-injury cases was 33 (five years).

Head/Face Chest Abdomen

Most-Injured Body Region in Fatal and Serious-injury Accidents per Quasi-ΔV (Passenger)

ΔV of Regulation Level

0

50

100

150

200

250

300

350

400


～48

Num

ber o

f fat

aliti

es a

nd s

erio

us in

jure

d

Conversion-ΔV (km/h)

60～

48～

Definition of Fatal and Serious Injured Rate

Fatal and serious injured rate

= ( Numbers of fatalities and serious injured persons)

/(Numbers of fatalities, serious and minor injured persons)

Quasi-ΔV1 =V1 - (M1 * V1 + M2 * V2)/ (M1 + M2)

V ： travel speed

ΔV is about 70-80% of quasi-ΔV.

Conversion-ΔV = 0.8 * Quasi-ΔV

V1 V2

M1 M2

0%

2%

4%

6%

8%

10%

12%

14%


Fata

l and

Ser

ious

inju

red

Rate

40～50 50～60 60～70 70～80 80～


32～40 40～48 48～56 56～64 64～

Fatal and Serious Injured Rate per Most Injured Body Region and Quasi-ΔV (Passenger)

• Fatal and serious injured rate of chest was higher than head or abdomen.• Fatal and serious injured rate of chest at lower ΔV than the regulation

level is higher.

Head/Face Chest Abdomen ΔV of Regulation Level

0

20

40

60

80

100

120

140

Num

ber o

f fat

aliti

es a

nd s

erio

us in

jure

d


40～50 50～60 60～70 70～80 80～

～24 24～32 32～40 40～48 48～56 56～64 64～Conversion-ΔV (km/h)

• In fatal and serious-injury accidents whose ΔV were below than the regulatory level, the number of head-injury cases was 52, chest-injury cases was 363 and abdomen-injury cases was 74 (five years).

• In fatal and serious-injury accidents whose ΔV were over the regulatory level, the number of head-injury cases was 17, chest-injury cases was 60 and abdomen-injury cases was 33 (five years).

Head/Face Chest Abdomen

Most-Injured Body Region in Fatal and Serious-injury Accidents per Quasi-ΔV (Passenger)


0

50

100

150

200

250

300

350

400


～48

Num

ber o

f fat

aliti

es a

nd s

erio

us in

jure

d

Conversion-ΔV (km/h)

60～

48～

0%10%20%30%40%50%60%70%80%90%

100%


Fata

l and

Ser

ious

inju

red

Rate

40～50 50～60 60～70 70～80 80～


32～40 40～48 48～56 56～64 64～

0%5%

10%15%20%25%30%35%40%45%50%


40～50 50～60


32～40 40～48

Fata

l and

Ser

ious

inju

red

Rate

Fatal and Serious Injured Rate per Most Injured Body Region and Quasi-ΔV (Age and Sex)

• Fatal and serious injured rate of elderly and female occupants was higher than younger and male occupants.

• Fatal and serious injured rate at lower ΔV than the regulation level is not so small as though the younger occupants.

ΔV of Regulation LeveltotalMale 18-64 Male over 65

Female 18-64 Female over 65

0

500

1000

1500

2000

2500

3000

3500

4000

Num

bers

of t

he to

tal o

f fat

aliti

es,

serio

us a

nd m

inor

inju

re


40～50 50～60 60～70 70～80 80～


32～40 40～48 48～56 56～64 64～

0

5000

10000

15000

20000

25000

Num

bers

of t

he to

tal o

f fat

aliti

es,

serio

us a

nd m

inor

inju

re


40～50 50～60 60～70 70～80 80～


32～40 40～48 48～56 56～64 64～

Numbers of Fatalities, Serious and Minor Injured per Quasi-ΔV (Age and Sex)


• The numbers of lower speed accidents were very large.

Driver Passenger


0

20

40

60

80

100

120

140

160

Num

bers

of t

he to

tal o

f fat

aliti

es a

nd s

erio

us in

jure


40～50 50～60 60～70 70～80 80～


32～40 40～48 48～56 56～64 64～

0

100

200

300

400

500

600


40～50 50～60 60～70 70～80 80～


32～40 40～48 48～56 56～64 64～

Num

bers

of t

he to

tal o

f fat

aliti

es a

nd s

erio

us in

jure


• Numbers of fatalities and serious injured at lower ΔV than regulation level were lager.

Driver Passenger

Numbers of Fatalities and Serious Injured per Quasi-ΔV (Age and Sex)


DriverAM50

PassengerAM50

50km/h

50 km/h FWRB test

Full Vehicle FWRB Test

0

1

2

3

4

5

6

7

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150

Forc

e(k

N)

Time (ms)

Driver Passsenger

Shoulder Outer Belt Force

Injury Criteria unit D P

Chest Rib Deflection mm 31.2 25.2

Injury Measures

• The chest deflection of passenger was lower than driver without airbags conditions, and probably one of the reasons was the difference of the force limiter.

Documents

1 Frontal Accident Research Data in Japan Frontal Accident Research Data in Japan JASIC 29 January 2014