ISO/TR 13330:2013

Road vehicles — Calculation processes for the neck injury criteria in rear impact

ISO/TR 13330:2013 recommends calculation procedures for several neck performance criteria for low-severity rear impact that are found in the literature. ISO/TR 13330:2013 does not recommend any particular criteria or provide injury risk curves since the mechanisms of whiplash injury are neither proven nor validated. Calculations given in ISO/TR 13330:2013 apply to mid-size adult male dummies only.

Véhicules routiers — Méthodes de calcul des critères lésionnels au cou en choc arrière

General Information

• Status: Published
• Publication Date: 15-Jan-2013
• ICS: 43.020 - Road vehicles in general
• Technical Committee: ISO/TC 22/SC 36 - Safety and impact testing
• Drafting Committee: ISO/TC 22/SC 36/WG 6 - Performance criteria expressed in biomechanical terms
• Current Stage: 6060 - International Standard published
• Due Date: 31-Jan-2013
• Completion Date: 16-Jan-2013

Standards Content (Sample)

TECHNICAL ISO/TR
REPORT 13330
First edition
2013-02-01
Road vehicles — Calculation
processes for the neck injury criteria
in rear impact
Véhicules routiers — Méthodes de calcul des critères lésionnels au cou
en choc arrière
Reference number
ISO/TR 13330:2013(E)
©
ISO 2013

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ISO/TR 13330:2013(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2013
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any
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Published in Switzerland
ii © ISO 2013 – All rights reserved

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ISO/TR 13330:2013(E)

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 General recommendations . 1
4 Calculation process defined for each criterion . 2
4.1 Upper neck loads . 2
[1][2] 3
4.2 NIC .
[3] 4
4.3 Nij .
[4] [5]
4.4 Nkm ( , ).14
[6]
4.5 LNL ( ) .16
Bibliography .19
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ISO/TR 13330:2013(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International
Standards adopted by the technical committees are circulated to the member bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the member bodies
casting a vote.
In exceptional circumstances, when a technical committee has collected data of a different kind from
that which is normally published as an International Standard (“state of the art”, for example), it may
decide by a simple majority vote of its participating members to publish a Technical Report. A Technical
Report is entirely informative in nature and does not have to be reviewed until the data it provides are
considered to be no longer valid or useful.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO/TR 13330 was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 12,
Passive safety crash protection systems.
iv © ISO 2013 – All rights reserved

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TECHNICAL REPORT ISO/TR 13330:2013(E)
Road vehicles — Calculation processes for the neck injury
criteria in rear impact
1 Scope
This Technical Report recommends calculation procedures for several neck performance criteria for
low-severity rear impact that are found in the literature. This Technical Report does not recommend any
particular criteria or provide injury risk curves since the mechanisms of whiplash injury are neither proven
nor validated. Calculations given in this Technical Report apply to mid-size adult male dummies only.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 6487, Road vehicles — Measurement techniques in impact tests — Instrumentation
SAE J211-1:2003, Instrumentation for Impact Test —Part 1: Electronic Instrumentation
3 General recommendations
Raw data (unfiltered) must be used as input in the calculation process (including filtering as a first step)
described below in this Technical Report.
Sign conventions and the reference frame are those described in SAE J211-1 and shown in Figure 1.
+Y
+X
+Z
Figure 1 — Reference coordinate system
The positive x-axis will be directed forward.
The positive y-axis will be directed from the dummy’s left to its right side.
The positive z-axis will be directed downward from head to toe.
For neck loads, polarities should be checked with the following manipulations:
— Fx > 0: head rearward, chest forward;
— Fy > 0: head leftward, chest rightward;
— Fz > 0: head upward, chest downward;
— Mx > 0: left ear toward left shoulder;
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ISO/TR 13330:2013(E)

— Mx > 0: left ear toward left shoulder;
— My > 0: chin toward sternum;
— Mz > 0: chin toward left shoulder.
The neck forces and moment can be divided in several portions:
— The anterior portion of the neck force about the x-axis is defined as the positive portion of the neck
force about the x-axis measurement. The posterior portion is defined as the negative portion.
— The extension portion of the neck force about the z-axis is defined as the positive portion of the neck
force about the z-axis measurement. The compression portion is defined as the negative portion.
— The flexion portion of the neck moment calculated at the occipital condyles about the y-axis is
defined as the positive portion of the measurement, while extension portion is considered as the
negative portion.
Film or animation video should be available in order to check the main events, such as head contact with
the head rest.
4 Calculation process defined for each criterion
4.1 Upper neck loads
4.1.1 Measurements used
F ()t : Upper neck force about the x-axis in N.
xu__pper neck
F ()t : Upper neck force about the z-axis in N.
zu__pper neck
4.1.2 Measurement filtering
The raw data are filtered using the filters as indicated in Table 1.
Table 1 — Filtering of the measurements used in the calculation process of the upper neck loads
following ISO 6487 or SAE J211-1
CFC Measurements
F ()t
F ()t
1000
xu__pperneck zu__pperneck


4.1.3 Zero offset measurements
Remove the offset of the filtered channels described in 4.1.1 “Measurements used”. The offset is defined
as the mean calculated over the last 10 ms of the measurement before the time of impact, i.e. the last
100 points for a data acquisition of 10 kHz.
4.1.4 Time window to define criteria for maximum/minimum value
The whole time window available is used to determine the minimum and/or maximum values.
4.1.5 Calculation process description
fo&
F =max [F ()t ]
xu__pper neck_max time_window
xu__pperneck
fo&
F =max [F ()t ]
zu__pper neck_max time_window
zu__pperneck
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ISO/TR 13330:2013(E)

fo&
F =min [F ()t ]
xu__pper neck_min time_window
xu__pperneck
fo&
F =min [F ()t ]
zu__pper neck_min time_window
zu__pperneck
where
fo& fo&
F ()t and F ()t are the upper neck forces in x and z directions after the
xu__pper neck zu__pper neck
filtering and correction of zero offset.
4.1.6 Dummy for which this criterion is calculated
This criterion can be calculated for any dummy for which measurements described above are available.
[1][2]
4.2 NIC
4.2.1 Measurements used
2
γ ()t : Head linear acceleration about the x-axis measured at the centre of gravity in m/s .
xh_ ead
2
γ ()t : T1 linear acceleration about the x-axis in m/s .
xT_ 1
4.2.2 Measurement filtering
The raw data are filtered using the filters as indicated in Table 2.
Table 2 — Filtering of the measurements used in the calculation process of the NIC according to
ISO 6487 or SAE J211-1
CFC Measurements
γ ()t
1000
xh_ ead

γ ()t
180
xT_ 1

4.2.3 Zero offset measurements
Remove the offset of the filtered channels described in 4.2.1 “Measurements used”. The offset is defined
as the mean calculated over the last 10 ms of the measurement before the time of impact, i.e. the last 100
points for a data acquisition of 10 kHz.
4.2.4 Time window to define criteria for maximum value
The time window to evaluate maximum NIC is until the time of end of head restraint contact.
4.2.5 Calculation process description
2
t
fo& fo& ffo& fo&
NICt=−max(02.* γγ() ()t +[(γ ()tt−γ ( ))] )
()
time_window
xT_ 11xh_ ead xT_ xh_ ead
∫
0
where
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ISO/TR 13330:2013(E)

fo& fo&
γ ()t and γ ()t are the T1 × and head x linear accelerations after the filtering and
xT_ 1 xh_ ead
correction of zero offset.
If T1 × is measured at two locations, e.g. left and right, T1 × is the mean of the two location measurements.
Firstly, filter each T1 × channel with CFC180, then calculate an average channel by adding both channels
and dividing by 2. Finally, determine the positive maximum between time zero and the time of end of
head restraint contact.
Constants of integration at time zero are 0 m/s.
4.2.6 Filtering after calculation process
NIC should not be filtered after calculation.
4.2.7 Dummy for which this criterion is calculated
This criterion can be calculated for any mid-size male dummy for which measurements described above
are available.
[3]
4.3 Nij
4.3.1 Measurements used
F ()t : Upper neck force about the x-axis in N.
xu__pper neck
F ()t : Upper neck force about the z-axis in N.
zu__pper neck
M ()t : Upper neck moment about the y-axis in N.m.
yu__pperneck
4.3.2 Measurements filtering
The raw data are filtered using the filters as indicated in Table 3.
Table 3 — Filtering of the measurements used in the calculation process of the Nij according to
ISO 6487 or SAE J211-1
CFC Measurements
F ()t F ()t
1000
xu__pperneck zu__pperneck

M ()t
600
yu__pper neck
4.3.3 Zero offset measurements
Remove the offset of the filtered channels described in 4.3.1 “Measurements used”. The offset is defined
as the mean calculated over the last 10 ms of the measurement before the time of impact, i.e. the last 100
points for a data acquisition of 10 kHz.
4.3.4 Time window to define criteria for maximum value
The maximum of the Nij components should be calculated on the whole time window available.
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4.3.5 Calculation process description
fo&
fo&
F ()t
MOC ()t
zu__pperneck y
Nij=+max ( )
time_window
Fzc Myc
where
is the upper neck force about the z-axis either in compression or in tension
fo&
F ()t
zu__pper neck after the filtering and correction of zero offset;
fo&
is the moment calculated at the occipital condyles about the y-axis either in
MOC ()t
y
flexion or in extension after the filtering and correction of zero offset;
F and M are the critical values for upper neck force about the z-axis and for the
zc yc
moment calculated at the occipital condyles about the y-axis.
The critical values (intercepts) used are included in Table 4.
Table 4 — Critical values used in Nij calculation for mid-size male
F tension (N) F compression (N) M flexion (Nm) M extension (Nm)
zc zc yc yc
6806 -6160 310 -135
 
fo& fo& fo&
=− ()
MOC ()tM ()tD*F t
 
y
yu__pperneck xu__pperneck
 
where
is the upper neck force about the x-axis after the filtering and correction of
fo&
F ()t
zero offset (see Figure 2);
xu__pper neck
fo& is the upper neck moment about the y-axis after the filtering and correction
M ()t
yu__pperneck
of zero offset (see Figure 3);
D is the distance between the measurement centre of the upper neck load cell
and the occipital condyles about the z-axis.
Checking the value of D distance relevant for the sensor model used with the sensor manufacturer is required.
fo&
MOC ()t should not be filtered after calculation.
y
Examples of upper neck forces and upper neck moments are given in Figures 2 and 3.
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ISO/TR 13330:2013(E)

Y
700
600
500
400
300
200
100
0
X
-100
-0,02 0,08 0,18 0,28 0,38
Key
X time in seconds
Y upper neck force
fo&
Figure 2 — Example of F ()t (upper neck force about the z-axis after the filtering
zu__pper neck
and correction of zero offset)
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Y
10
5
0
X
-5
-10
-15
-20
-25
-0,02 0,08 0,18 0,28 0,38
Key
X time in seconds
Y upper neck moment
fo&
Figure 3 — Example of M ()t (upper neck moment about the y-axis after the
yu__pperneck
fo&
filtering and correction of zero offset) (black curve) and MOC ()t (moment calculated at the
y
occipital condyles about the y-axis either in flexion or in extension after the filtering and
correction of zero offset) (green curve)
To determine the Nij maximum value, four intermediate calculations must be made. These calculations
fo&
use the upper neck force about the z-axis F ()t (in tension or in compression) with the
zu__pper neck
fo&
moment calculated at the occipital condyles about the y-axis MOC ()t (in flexion or extension). This
y
results in four combinations of the two data channels:
fo& fo&
Ncf where F ()t is in compression and MOC ()t in flexion;
y
zu__pper neck
fo&
fo&
Nce where F ()t is in compression and MOC ()t in extension;
y
zu__pper neck
fo&
fo&
Ntf where F ()t is in tension and MOC ()t in
...