1

ProposalProposal for for ECEECE R17R17--0808Dynamic Dynamic BacksetBackset Option Option withwith BioRID IIBioRID II

JASIC/Japan

Dec. 2008

Informal document No.GRSP-44-24(4４th GRSP, 10-12 Dec 2008,agenda item 12b))

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Some cr iter ia with BioRID IIUntil BioRID II requirementsare included in this gtr or

adopted in the national r egulation of a Contracting Par ty, head restraints shall comply with any or all static r equirements.

R-point with Backset < 45mm

Static Dynamic Option

OR*

Backset Requirements in Head restraint gtr phase1

Head Restraint gtr , WP29/2008/54 and /55, was agreed at #144 WP29 in March. ’08,

Contracting Par ties may allow manufacturers to choose

*: Manufacture’s choice

H-point with Backset < 55mmContracting Par ties choice

HY-IIIHead rotation < 12 deg HIC < 500

OR

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The number of The number of permanent permanent disabilities due to disabilities due to rearrear--end collisions end collisions have been have been significantly significantly increasingincreasing in Japanin Japan..The countermeasure should be effective and quick.The countermeasure should be effective and quick.

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

H4 H5 H6 H7 H8 H9 H10 H11 H12 H13 H14

年

後遺障害者数

（人

）

人対車両

正面衝突

追突

出会い頭

右左折時

相互その他

車両単独

その他

Human-vehicle

Full-frontal crash

Rear-end collision

Head-on collision

During right/Left turn

Othermulti-vehicle

Single vehiclecrash

Others

Num

ber o

f Dis

abili

ties

(per

son)

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

Motivation of this Amendment proposal

Yearly Change in the Number of permanent Disabilities by Accident Type in Japan (Total Disabilities in 1992-2002)

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BioRID II requirement[Reserved for future use when dummy and criteria are agreed.]

R-point with Backset < 45mm

Static Dynamic Option

OR*

Motivation of this Amendment proposal

ECE R17-08 ser ies amendment, GRSP/2008/11 has been proposed as follows.

manufacturers to choose

*: Manufacture’s choice

H-point with Backset < 55mm

Active or r eactive head restraints are not required to comply with Backset requirements.

Japan would like to proposeJapan would like to proposeBBio RID IIio RID II requirement requirement becausebecauseof following reasons. of following reasons.

--to assure active or reactive to assure active or reactive head restraints performancehead restraints performance..

--to avoid active, reactive andto avoid active, reactive andprepre--activeactive definition trouble definition trouble and design restriction. and design restriction.

--to provide equal dynamic to provide equal dynamic option opportunity for all seat option opportunity for all seat types. types.

50 10 20 30 40 50 60 70

Number of seats

Good

Acceptable

Marginal

Poor

Static backset:58mm - 152mm

Motivation of this Amendment proposal

Performance levelPerformance level of of reactive head restraints are not always GOOD reactive head restraints are not always GOOD according to IIHS test results. according to IIHS test results. ““PoorPoor”” ranking seats are out of static ranking seats are out of static backset requirement. backset requirement.

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WhiplashPhenomenon

Phase I:Before Head/Head restraint contact

Phase II:AfterHead/Head restraintcontact

Phase III:Rebound

contactBackset extension flexion

Condition of Dynamic Test for gtr phase1

••Dynamic test for Head restraint gtr Dynamic test for Head restraint gtr Phase1Phase1 should be an alternative should be an alternative test for static Backset, and had better to equivalent to static test for static Backset, and had better to equivalent to static backset.backset.••It is considered to evaluate following phase I stage of whiplashIt is considered to evaluate following phase I stage of whiplashphenomenon.phenomenon. gtr Phase1

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Condition of Dynamic Test for gtr phase 1

•• BioRID II is promising with its high biofidelity to the human boBioRID II is promising with its high biofidelity to the human body, dy, but still need to study injury criteria indicators, reference vabut still need to study injury criteria indicators, reference values, lues, test pulse, etc. for appropriate dynamic test as we propose as itest pulse, etc. for appropriate dynamic test as we propose as in n phase 2 activity.phase 2 activity.

•• EEVC WG20 and Japan have recognized that a Geometrical EEVC WG20 and Japan have recognized that a Geometrical indicator of BioRID II is feasible now. indicator of BioRID II is feasible now.

T1G

MyFx

FzHead G

Phase2Phase2NIC, Nkm, Nij, LNL,NDCNIC, Nkm, Nij, LNL,NDC……..

X

Phase1Phase1Geometric indicatorGeometric indicator

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Proposal for Dynamic Test for ECE R17-08

HybridHybrid--IIIIII BioRIDBioRID IIII RID3DRID3D

VolunteerVolunteerBioRIDBioRID IIII

The head The head O.C. (O.C. (Occipital Condyle) xx--axis displacement with respect axis displacement with respect to T1 was proposed as a candidate of geometric indicator from thto T1 was proposed as a candidate of geometric indicator from the e result of result of EEVCEEVC WG12WG12 and Japanand Japan（（JARI)JARI) joint assessmentjoint assessment of Rear Impact Dummy Biofidelity.

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Definition of Dynamic Backset

Proposal for Dynamic Test for ECE R17-08

))(),(())(),((1))(),((1

))(),(())(),(())(),((tZtXSBLtZtXTtZtXT

tZtXSBLtZtXOCtZtXOC

SBL

SBL

initialtt )()(

)(sin1)(cos1)('1

)(sin)(cos)('tZTtXTtXT

tZOCtXOCtXOC

SBLSBLSBL

SBLSBLSBL

)('1)(')( D T1-OC tXTtXOCt SBLSBL

Dynamic backset , maximum OC-T1 relative displacement, shall be calculated as the maximum absolute value of D’OC-T1(t) , whichever is larger between both seat sides.

Note: The measurements data shall be considered for evaluation until the point in time at which the head rebounds from the head restraint or at 300 ms after T-zero, whichever occurs first.

DOC-T1 (0) DOC-T1 (t )θ(t )

θ(t )

-: t = 0-: t = t

D’OC-T1 (t) = D OC-T1 (t) － D OC-T1 (0)

))(())(())(())((tan)( 1

tXSBLtXSBUtZSBLtZSBUt

+X

+Z

+θ

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①:Set BioRID II head with +15+/-2mmdistance to static backset

Proposal for Dynamic Test for ECE R17-08

②:Measure “Dynamic backset” at △V＝16km/h sled test

Sled Pulse

・Head O.C. （Occipital Condyle)・Head C.G. (Centre of Gravity)

O.C.O.C.

T1T1

SBUSBU

SBLSBL

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Coefficient of determination Relation between static backset and various BioRID II indicators

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0.99

0.96

0.93

0.76

0.89

0.75

0.89

0.72

0 0.2 0.4 0.6 0.8 1

Dynamic Backset

T-HRC

Rebound V

NIC

Nkm

T1G

UNFX

UNFZ

““Dynamic backsetDynamic backset”” shows the highest coefficient rate (Rshows the highest coefficient rate (R22) among ) among all indicatorsall indicators by MADYMO simulation study.by MADYMO simulation study.

Coefficient Rate (R2)

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Sensitivity analysis by MADYMO simulation

Dynamic backset has a potential to show the effect of Dynamic backset has a potential to show the effect of passive, active and WHIPS type antipassive, active and WHIPS type anti -- whiplash seatswhiplash seats. .

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50

55

60

65

70

80% 90% Base 110% 120%Factor

Dyn

amic

Bac

kset

[mm

]

Horizontal distance between head andhead restraint ( Static backset + 15mm )Distance from top of head

Seat hinge stiffness

Seat back contact stiffness

Effect of WHIPS seat

Effect of Active & Reactive HR

Effect of Passive seat

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Repeatability, Reproducibility and Threshold Evaluation Tests

33 seats were tested at 6 different laboratories in cooperation with EEVC WG20.

IIHS Ranking Seat Type Number (*:EEVC data)

Good

Normal 4Reactive 2(3*)Passive 2WHIPS (1*)

AcceptableNormal 1

Reactive (1*)Passive 2

MarginalNormal 1

Reactive 1Passive 4

PoorNormal 5

Reactive 5Passive 1

Total 33

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BioRID-II

Repeatability EvaluationTest method

The repeatability of following indicators were evaluated by 3 seats about 3 seat types. ・Dynamic backset (Head O.C. –T1), Fx, My, etc.

X = Mean value of each indicator maximum value

Sd ＝ Standard deviation of each indicator maximumvalue

Method of evaluation

Comparison of coefficient of variation （CV）

Criteria Admissible level: CV≦10

Repeatability C.V = 100 (%) XXS d

15

0.0

5.0

10.0

15.0OC-T1

Hx Acc .

T1-R Acc.

T1-L Acc.

UpperFX

UpperFZ

UpperMY-Flx.

UpperMY-Ext.

Normal Passive Re-Active

Upper Neck-MY

-30

-20

-10

0

10

20

30

40

0 50 100 150 200 250 300Time[ms]

Mo

me

nt[

Nm

]

0 809-B-01 0809-B-02

0809-B-03

Upper Neck-FX

-200

-100

0

100

200

300

400

0 50 100 150 200 250 300

T ime[ms]

Fo

rce

[N]

0 809-B-01

0809-B-02

0809-B-03

Upper neck MY show slight variation.

Repeatability EvaluationDynamic backset showDynamic backset showss goodgood repeatabilityrepeatability..

Dynamic Backset Head O.C.-T1

-100

-80

-60

-40

-20

0

20

40

60

80

0 50 100 150 200 250

Time[ms]

Rela

tive D

ispla

cem

ent[

mm

]

0809-B-01 0809-B-020809-B-03

Normal 4.3Passive 1.6

Re-Active 2.5

OC-T1 (mm)Standard Deviation

Dynamic backset

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BioRID-II

Reproducibility EvaluationTest method

The reproducibility of following indicators were evaluated by 3 dummies about 3 seat types. ・Dynamic backset (Head O.C. –T1), Fx, My, etc.

X = Mean value of each indicator maximum value

SB ＝ ［ ］

Method of evaluation

Comparison of coefficient of variation （CV）

Criteria Admissible level: CV≦10

Reproducibility C.V = 100 (%) XXSB

nMSB - MSW 1/2

MSB = Square average of Maximum value and Minimum valueMSW = Square average of All valuen = number of tests

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0 .0

5 .0

10 .0

15 .0OC-T1

Hx Acc .

T1-R Acc.

T1-L Acc.

UpperFX

UpperFZ

UpperMY-Flx.

UpperMY-Ext.

Normal Passive Re-Active

Upper Neck-MY

-30

-20

-10

0

10

20

30

40

0 50 100 150 200 250 300T ime[ms]

Mo

me

nt[

Nm

]

0 809-B-01 0809-B-020809-B-03 0809-B-040809-B-05

Upper Neck-FX

-200

-100

0

100

200

300

400

0 50 100 150 200 250 300

T ime[ms]

Fo

rce

[N]

0 809-B-01

0809-B-02

0809-B-03

0809-B-04

0809-B-05

Fx and Upper neck MY show large variation.

Reproducibility EvaluationDynamic backset showDynamic backset showss good good reproducibility.reproducibility.

Dynamic Backset Head O.C.-T1

-100

-80

-60

-40

-20

0

20

40

60

80

0 50 100 150 200 250

Time[ms]

Rela

tive D

ispla

cem

ent[

mm

] 0809-B-01 0809-B-02

0809-B-03 0809-B-04

0809-B-05

Dynamic backset

180

10

20

30

40

50

60

70

80

0 20 40 60 80 100 120Static Backset（HRMD) [mm]

Dynam

ic b

ackset

[mm

]

Normal

Reactive

Passive

WHIPS

Dynamic Backset shows Dynamic Backset shows correlationcorrelation between normal seat static backset , between normal seat static backset , and show the effect of reactive, passive and WHIPS type seats.and show the effect of reactive, passive and WHIPS type seats.About About [48mm] [48mm] dynamic backset isdynamic backset is equal to achieve equal to achieve 55 mm HRMD static 55 mm HRMD static backset requirementbackset requirement. .

Normal seat correlation line

48

55

Threshold study for Static Backset

＊EEVC WG20data

190

10

20

30

40

50

60

70

80

ＩＩWPG　Ranking

Dynam

ic B

ackset

[mm

]

Normal

Reactive

Passive

WHIPS

Threshold study for IIWPG Ranking About About [4[488mm]mm] Dynamic backset is Dynamic backset is equivalent to equivalent to aachieve chieve minimum performance levelminimum performance level ofof IIWPG IIWPG ““GOODGOOD”” rating. rating.

Poor Marginal Acceptable Good

＊EEVC WG20data

48

20

Max. OC-T1 vs Hybrid Ⅲ Head Angle

0

10

20

30

40

50

60

70

80

0 5 10 15 20 25 30 35Hybrid Ⅲ Head Angle [deg]

Max

. H

ead

O.C

.Move

ment

[mm

]

Normal

Reactive

Passive

WHIPS＊

＊

Threshold study for Hybrid III head rotation

＊

48

＊

12

＊EEVC WG20data

＊

[48mm][48mm] Dynamic backset is Dynamic backset is equivalent to equivalent to achieve 12 achieve 12 degree head rotation angle with Hybrid III. degree head rotation angle with Hybrid III.

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Bio RID II Dynamic backset < [52mm]

R-point with Backset < 45mm

Static Dynamic Option

OR*

Proposal for ECE R17-08

*: Manufacture’s choice

H-point with Backset < 55mm

OR*

Japan has proposed following manufacturerJapan has proposed following manufacturer ’’s option for all type of seats. s option for all type of seats. Dynamic backset threshold is proposed [52mm] (=48mm + 4mm var iatDynamic backset threshold is proposed [52mm] (=48mm + 4mm var iat ion).ion).

220

10

20

30

40

50

60

70

80

0 20 40 60 80 100 120Static Backset（HRMD) [mm]

Dynam

ic b

ackset

[mm

]

Normal

Reactive

Passive

WHIPS

This proposed threshold could be excluding lower performance This proposed threshold could be excluding lower performance reactive type head restraints.reactive type head restraints.

52

55

Effect of this proposed Threshold

＊EEVC WG20data

Excluding lower performance reactive HR

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Conclusion

Dynamic backset (Maximum x displacement of Head Dynamic backset (Maximum x displacement of Head O.C.O.C.-- T1) is considered as a reasonable dynamic T1) is considered as a reasonable dynamic geometric indicator for BioRID II geometric indicator for BioRID II forfor following reasons. following reasons.

Reasonable repeatReasonable repeataability and reproducibilitybility and reproducibility

Correlation with static backset, Correlation with static backset, IIIIWPGWPG ranking and ranking and field long term injury evaluations.field long term injury evaluations.

Reflection of passive,Reflection of passive, reactive and WHIPS type seats reactive and WHIPS type seats effect. effect.

Dynamic backset threshold is proposed as a Dynamic backset threshold is proposed as a equivalent equivalent level for level for static backset, IIWG GOOD ranking and Hybrid static backset, IIWG GOOD ranking and Hybrid III head rotation requirements with 4mm measurement III head rotation requirements with 4mm measurement variation, and excluding lower performance active HR.variation, and excluding lower performance active HR.

Dynamic backsetDynamic backset << [52[52]]mmmm

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Thank You