Road vehicles — Visibility — Method for establishment of eyellipses for driver's eye location

This document establishes the location of drivers' eyes inside a vehicle. Elliptical (eyellipse) models in three dimensions are used to represent tangent cut-off percentiles of driver's eye locations. Procedures are provided to construct 95th and 99th percentile tangent cut-off eyellipses for a 50/50 gender mix, adult user population. Neck pivot (P) points are defined to establish specific left and right eye points for direct and indirect viewing tasks described in SAE J1050. These P points are defined only for adjustable seat eyellipses. This document applies to Class A vehicles (passenger cars, multipurpose passenger vehicles and light trucks) as defined in SAE J1100. It also applies to Class B vehicles (heavy trucks).

Véhicules routiers — Visibilité — Méthode de détermination des ellipses oculaires correspondant à l'emplacement des yeux des conducteurs

General Information

Status
Published
Publication Date
16-Jun-2022
Current Stage
6060 - International Standard published
Due Date
12-Apr-2021
Completion Date
17-Jun-2022
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INTERNATIONAL ISO
STANDARD 4513
Fourth edition
2022-06
Road vehicles — Visibility — Method
for establishment of eyellipses for
driver's eye location
Véhicules routiers — Visibilité — Méthode de détermination des
ellipses oculaires correspondant à l'emplacement des yeux des
conducteurs
Reference number
ISO 4513:2022(E)
© ISO 2022
---------------------- Page: 1 ----------------------
ISO 4513:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

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Published in Switzerland
© ISO 2022 – All rights reserved
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ISO 4513:2022(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction .................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ..................................................................................................................................................................................... 1

3 Terms and definitions .................................................................................................................................................................................... 1

4 Adjustable seat 95th and 99th percentile tangent cut-off eyellipses for a 50/50 male

and female gender mix .................................................................................................................................................................................. 4

4.1 Reference anthropometry ............................................................................................................................................................ 4

4.2 Axis lengths ............................................................................................................................................................................................... 5

4.3 Axis angles.................................................................................................................................................................................................. 6

4.3.1 Rear and plan view angles ......................................................................................................................................... 6

4.3.2 Side view angle, β ............................................................................................................................................................... 6

4.4 Centroid locations ................................................................................................................................................................................ 6

4.4.1 Locating formulae ............................................................................................................................................................. 6

4.4.2 Seats with vertical adjustment .............................................................................................................................. 7

4.4.3 Left, right, mid-eye centroids .................................................................................................................................. 8

5 Eyellipse locating procedure, Class A vehicles ..................................................................................................................... 8

6 Neck pivot (P) and eye (E) points: locating procedure, Class A vehicles ..................................................9

6.1 Background ............................................................................................................................................................................................... 9

6.2 Neck pivot (P) points ......................................................................................................................................................................... 9

6.3 Eye (E) points .......................................................................................................................................................................................... 9

Annex A (informative) Adjustable seat tangent cut-off eyellipses for any user population

stature distribution and gender mix ...........................................................................................................................................11

Annex B (informative) Fixed seat 95th and 99th percentile tangent cut-off eyellipses for an

adult population at a 50/50 gender mix ...................................................................................................................................18

Annex C (informative) Fixed seat tangent cut-off eyellipses for any user population stature

distribution and gender mix ................................................................................................................................................................21

Annex D (informative) Tangent cut-off eyellipses and inclusive eyellipses ...........................................................26

Annex E (informative) Eyellipses for Class B vehicles ....................................................................................................................29

Annex F (informative) Background to the revision of this document ..........................................................................33

Bibliography .............................................................................................................................................................................................................................35

iii
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ISO 4513:2022(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.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

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. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to

the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see

www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 35,

Lighting and visibility.

This fourth edition cancels and replaces the third edition (ISO 4513:2010), which has been technically

revised.
The main changes are as follows:
— added references to the annexes;
— the variables have been modified;
— editorial changes.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www.iso.org/members.html.
© ISO 2022 – All rights reserved
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ISO 4513:2022(E)
Introduction

This document describes the eyellipse, a statistical representation of driver eye locations, which is used

to facilitate design and evaluation of vision in motor vehicles. Examples of eyellipse applications include

rearview mirror size and placement, wiped and defrosted areas, pillar size and location, and general

exterior field of view. These applications are covered in other SAE and ISO practices.

This revision of the eyellipse is the most significant update to ISO 4513 since its inception. The eyellipses

differ from the previous eyellipses in the following ways:
a) the axis angles in plan view and rear view are parallel to vehicle grid;
b) the side view X-axis angle is tipped down more at the front;
c) for the 95th percentile eyellipse (99th shown in parentheses):
1) the X-axis length is 7,5 (18,9) mm longer,
2) the Y-axis is 44,6 (63,6) mm shorter,
3) the Z-axis is 7,4 (10,1) mm longer;
d) the centroid location is generally higher and more rearward;

e) the centroid location in side view is a function of packaging geometry (SgRP, steering wheel

location, seat cushion angle, and the presence or absence of a clutch pedal);
f) the eyellipse is no longer positioned according to the driver's torso angle;

g) the eyellipse for seat tracks shorter than 133 mm in length has an X-axis length unchanged from

ISO 4513:2003. The Y- and Z-axis lengths, and the centroid location, are based on the new values

and equations given in this document;

h) neck pivot (P) and eye (E) points are based on the previous plan view sight lines to rear-view

mirrors and A-pillars, but are adjusted to the shape and location of the new eyellipses.

New additions, incorporated as annexes, are summarized as follows.

a) Fixed seat eyellipses for an adult user population at a 50/50 gender mix and 95th and 99th percentile

tangent cut-offs are described (see Annex B). Fixed seat eyellipses and their locating formulae given

in Annexes B and C are based on data for second row passenger eye locations presented by UMTRI.

In addition, a procedure is provided in Annex B for locating an eyellipse in a second row seat that

has adjustable seat track travel or adjustable back angle.

b) A procedure is given for calculating adjustable and fixed seat eyellipses for any user population

stature and gender mix at selected percentile tangent cut-offs (see Annexes A and C).

Tables providing comparisons between tangent cut-off eyellipses and inclusive eyellipses are given. An

inclusive eyellipse can be constructed using these tables (see Annex D).
Eyellipses for Class B vehicles are unchanged from ISO 4513:2003 (see Annex E).
For historical background of ISO 4513 see Annex F.
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INTERNATIONAL STANDARD ISO 4513:2022(E)
Road vehicles — Visibility — Method for establishment of
eyellipses for driver's eye location
1 Scope

This document establishes the location of drivers' eyes inside a vehicle. Elliptical (eyellipse) models in

three dimensions are used to represent tangent cut-off percentiles of driver's eye locations. Procedures

are provided to construct 95th and 99th percentile tangent cut-off eyellipses for a 50/50 gender mix,

adult user population.

Neck pivot (P) points are defined to establish specific left and right eye points for direct and indirect

viewing tasks described in SAE J1050. These P points are defined only for adjustable seat eyellipses.

This document applies to Class A vehicles (passenger cars, multipurpose passenger vehicles and light

trucks) as defined in SAE J1100. It also applies to Class B vehicles (heavy trucks).

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements 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 6549, Road vehicles — Procedure for H- and R-point determination
SAE J1100, Motor Vehicle Dimensions
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 6549, SAE J1100 and the

following apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
eyellipse

contraction of the words “eye” and “ellipse” used to describe the statistical distribution of eye locations

in a three-dimensional space located relative to defined vehicle interior reference points

Note 1 to entry: See Figure 1.
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ISO 4513:2022(E)
Key
X, Y, Z ellipse axes

Figure 1 — Typical three-dimensional tangent cut-off eyellipse for the left and right eyes

3.2
mid eye centroid
mid-eye point
cyclopean eye point

midpoint between left and right eye points or left and right eyellipse centroids at the centreline of the

occupant
3.3
tangent cut-off plane
plane tangent to an eyellipse

Note 1 to entry: When projected at a specified angle or on to a specific target, a tangent cut-off plane can be

considered to be a sight plane. In a two-dimensional view, a sight plane can be considered to be a sight line (see

Figure D.1).
3.4
tangent cut-off eyellipse

three-dimensional eyellipse derived as the perimeter of an envelope formed by an infinite number of

planes dividing the eye locations so that P % of the eyes are on one side of the plane and (100 − P) % are

on the other
Note 1 to entry: See Annex D.
3.5
neck pivot point
P point
point at which a driver's head turns on a horizontal plane
Note 1 to entry: See Figure 2.
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ISO 4513:2022(E)
3.6
point P1
point P2

neck (head) pivot points used to position eye points for measuring the driver binocular obstruction due

to A-pillars at the left and right side of the vehicle
Note 1 to entry: See Figure 2.
3.7
point P3
point P4

neck (head) pivot points used to position eye points for measuring driver field of view from rear-view

mirrors located to the left and right of the driver
Note 1 to entry: See Figure 2.
Dimensions in millimetres
a) Plan view
b) Side view
Key
1 mid-eye centroid
NOTE Eyellipses are shown for reference purposes only.

Figure 2 — P point locations relative to 95th percentile eyellipse mid-eye centroid

with seat track travel >133 mm
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ISO 4513:2022(E)
3.8
eye point
E point

point representing an eye of the driver, used in conjunction with a neck pivot point to describe specific

viewing tasks
Note 1 to entry: See Figure 3.
Dimensions in millimetres
a) Plan view b) Side view
Key
E left eye
E right eye
P neck pivot point
1 driver head centreline
2 line, viewed end on, between E and E
L R
Figure 3 — Neck pivot point and associated eye points
3.9
inclusive eyellipse

eyellipse that contains a specified percentage of drivers' eyes within its boundaries

4 Adjustable seat 95th and 99th percentile tangent cut-off eyellipses for a
50/50 male and female gender mix
4.1 Reference anthropometry

These eyellipses are based on the user populations described in Table 1. Driver eyellipses for a 50/50

gender mix shall be used for designing Class A vehicles.
Table 1 — Reference anthropometry (see Reference [17])
Dimensions in millimetres
Standard deviation of
Gender Mean stature
stature
Male 1 755 74,2
Female 1 618 68,7

NOTE Standard deviations for each gender were estimated by dividing the difference

between the 95th and 5th percentiles by the difference in z-scores (3,29).
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ISO 4513:2022(E)

The 95th and 99th percentile tangent cut-off eyellipses for a 50/50 gender mix are constructed from

tables and formulae given in 4.2 to 4.3.2. These eyellipses are applicable to driver and front outboard

passenger seat locations.

NOTE 1 See Annex A for an example to determine adjustable seat tangent cut-off eyellipses for any user

population stature distribution and gender mix.

NOTE 2 See Annex B for an example to determine fixed seat 95th and 99th percentile tangent cut-off eyellipses

for an adult population at a 50/50 gender mix.

NOTE 3 See Annex C for an example to determine fixed seat tangent cut-off eyellipses for any user population

stature distribution and gender mix.
4.2 Axis lengths
Axis lengths are given in Table 2 (see Figure 4).
Table 2 — Left and right eyellipse axis lengths (true view)
Seat track travel
Percentile X-axis length Y-axis length Z-axis length
(TL23)
mm mm mm mm
>133 95 206,4 60,3 93,4
99 287,1 85,3 132,1
100 to 133 95 173,8 60,3 93,4
99 242,1 85,3 132,1

For seat track travels of 100 mm to 133 mm, the eyellipse X-axis length is unchanged from ISO 4513:2003. No new eye

position data were collected for these shortened seat track travels.
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ISO 4513:2022(E)
a) Plan view
b) Side view c) Rear view
Key
X X-axis length
a_l
Y Y-axis length
a_l
X X-axis length
a_l
Figure 4 — Adjustable seat tangent cut-off eyellipse for one eye, three views
4.3 Axis angles
4.3.1 Rear and plan view angles

The eyellipse is aligned with the vehicle axes in plan view (Z-plane) and rear view (X-plane), but it is

tilted down at the front in side view (Y-plane).
4.3.2 Side view angle, β

In side view, the angle, β, in degrees (positive, tipped down at the front from horizontal), of the eyellipse

is:
β =12,0 (1)
4.4 Centroid locations
4.4.1 Locating formulae

Formulae (2) to (5) are used to calculate the eyellipse centroid location (see Figure 5).

XL=− + 664 + 0,587 LH 0,176 − 12,5 t (2)
c1 630
YW=− 32,5 (3)
cL 20
YW=+ 32,5 (4)
cR 20
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ISO 4513:2022(E)
ZH=+ 638 + H (5)
c8 30
where
L is the x-coordinate of the BOFRP (L );
1 1
L is the x distance from the steering wheel centre to the BOFRP (L );
6 6
H is the z distance of the SgRP from the AHP (H );
30 30
t is the transmission type (1 with clutch pedal, 0 without clutch pedal);
W is the y-coordinate of the SgRP (W );
20 20
H is the z-coordinate of the AHP (H ).
8 8
4.4.2 Seats with vertical adjustment

For driver seats having vertical adjustment, Formulae (2) to (5) were developed with H30 (and SgRP)

positioned at the middle of the vertical adjustment range. Typically, this was 20 mm to 25 mm vertically

above the full down H-point travel path (Figure 5). If manufacturers define their SgRP so it is not

20 mm above the driver's full down H-point travel path, the accuracy in locating the vertical position of

the eyellipse using the manufacturer's H30 dimension in Formula (5) is reduced. If the H-point vertical

adjustment (TH21) is less than 40 mm, then H30 and the eyellipse Z centroid should be located from a

point midway between the full up and full down travel path.
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ISO 4513:2022(E)
Key
A seat track rise TL seat track travel
19 23
AHP accelerator heel point W y-coordinate of the SgRP
BOFRP ball of foot reference point X x-coordinate of the eyellipse centroid
location
H z-coordinate of the AHP Y mid-eye y-coordinate
8 cycl
H z distance of the SgRP from the AHP Z z-coordinate of the eyellipse centroid
30 c
location
L x-coordinate of the BOFRP β side view angle
L x distance from the steering wheel centre to BOFRP 1 zero X grid
L x-coordinate of the SgRP 2 zero Y grid
SgRP seating reference point 3 zero Z grid
TH H-point vertical adjustment 4 H-point travel path
Figure 5 — Eyellipse package factors, side view axis angle and centroid location
4.4.3 Left, right, mid-eye centroids

The distance between the left eye centroid, Y , and right eye centroid, Y , is 65 mm. The mid-eye

cL cR
(cyclopean eye), Y , is located on the occupant centreline at W20.
cycl
5 Eyellipse locating procedure, Class A vehicles
The steps in the procedure are:
a) determine seat characteristics A19, W20, H30, TL23;
b) determine H8 and L6;
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ISO 4513:2022(E)

c) determine t based on the percentage of vehicle production that has a clutch pedal — if 50 % or

more of anticipated production has a clutch pedal, set t = 1. Otherwise, set t = 0;

d) construct identical left and right eyellipses based on the axes given in Table 2;

e) locate the centroids using Formulae (2) to (5);

f) tilt the front of the eyellipse X-axis down in side view according to Formula (1).

NOTE See Annex E for description of eyellipses for Class B vehicles.
6 Neck pivot (P) and eye (E) points: locating procedure, Class A vehicles
6.1 Background

These points are defined to simplify application of the eyellipse for specific viewing tasks requiring

head and eye rotation in plan view (see SAE J1050). Neck pivot (P) points provide a plan view head

rotation pivot centre so the left and right eye (E) points can be repositioned for these specific viewing

tasks. These P points are derived from a 95th percentile, 50/50 gender mix eyellipse. To determine the

P points, tangents were constructed to a forward target (A-pillar or exterior rearview mirror). Each P

point was derived so that its left and right eye points were as close as possible to a tangent point on the

surface of a 3D 95th percentile eyellipse. P points were not developed for the 99th percentile eyellipse.

6.2 Neck pivot (P) points

Locate these points relative to the cyclopean (mid-eye) eyellipse centroid using values given in Table 3

(see Figure 2).

The X, Y and Z values in Table 3 may be added to Formulae (2), (3), (4) and (5), respectively, to obtain P

point locations relative to the vehicle grid.

Table 3 — Neck pivot points relative to the 95th percentile eyellipse mid-eye centroid

Dimensions in millimetres
Seat track travel Neck pivot point Y Y
X Z
(TL23) (P points) (Left-hand drive) (Right-hand drive)
>133 P1 0 −7,3 +7,3 −20,5
>133 P2 26,2 +20,6 −20,6 −20,5
>133 P3 191,0 −11,2 +11,2 +22,5
>133 P4 191,0 +11,2 −11,2 +22,5
<133 P1 16,3 −7,3 +7,3 −20,5
<133 P2 39,2 +20,6 −20,6 −20,5
<133 P3 175,0 −11,2 +11,2 +22,5
<133 P4 175,0 +11,2 −11,2 +22,5

NOTE Positive values of X are rearward of the centroid, positive values of Y are right of the centroid and positive values of

Z are above the centroid.
6.3 Eye (E) points

Position the eye (E) points relative to the P points as shown in Figure 3 and the following formulae:

EP=−98 (6)

1) P points cited in regulations differ from those in 6.1 if the regulations are based on ISO 4513:2003 or before. Use

the regulatory P points for compliance purposes.
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ISO 4513:2022(E)
EP=−32,5 (7)
EP=+32,5 (8)
EP= (9)
where
P is the x-coordinate of the P point;
P is the y-coordinate of the P point;
P is the z-coordinate of the P point;
E is the x-coordinate for the left and right eye point;
E is the z-coordinate for the left and right eye point;
E is the y-coordinate of the left eye;
E is the y-coordinate of the right eye.
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ISO 4513:2022(E)
Annex A
(informative)
Adjustable seat tangent cut-off eyellipses for any user population
stature distribution and gender mix
A.1 General

In this annex, a procedure is given for constructing eyellipses for driver populations that are different

from the standard population listed in Table 1, because the underlying stature distribution is different,

the gender mix is different, or a different tangent cut-off contour is desired. The user can apply the

formulae given in this annex for gender mixes containing 10 % to 75 % females. For larger or smaller

percentages of females in the driver population, the eyellipse side view axis angle and centroid Z

location are incorrect.
A.2 Axis angles

The eyellipse is aligned with the vehicle axes in plan view (Z-plane) and rear view (X-plane), but it

is tilted in side view (Y-plane). In side view the angle of the eyellipse is given in Formula (A.1) (see

Figure 5).
β =−18,6 A (A.1)
where A is the seat track rise angle (A19).
A.3 Reference centroid location
A.3.1 Locating formulae

The reference centroid for the normative part of this document, calculated using Formulae (A.2) to

(A.4), is based on a driver population defined by NHANES III anthropometry (see Reference [17]) and

consisting of 50 % males and 50 % females (see Table 1). The mean stature for this reference population

is 1 686 mm. A.6 describes how to adjust these formulae for other national driver populations.

XL =+ 664 +−0,,587LH 0 176 −12,5t (A.2)
cref 16 30
YW = (A.3)
cref 20
ZH =+ 638 +H (A.4)
cref 830
where
L is the x-coordinate of the BOFRP (L );
1 1
L is the x distance from the steering wheel centre to the BOFRP (L );
6 6
W is the y-coordinate of the SgRP (W );
20 20
H is the z-coordinate of the AHP (H );
8 8
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ISO 4513:2022(E)
H is the z distance of the SgRP from the AHP (H );
30 30
t is the transmission type (1 with clutch pedal, 0 without clutch pedal).
A.3.2 Seats with vertical adjustment

For driver seats having vertical adjustment, Formulae (A.2) to (A.4) were developed with H30 defined

approximately 20 mm above the driver's full down H-point travel path (see Figure 5). If manufacturers

define their SgRP at a vertical position that is not 20 mm above the full down H-point travel path, the

accuracy in locating the vertical position of the eyellipse is reduced. If the H-point vertical adjustment

(TH21) is less than 40 mm, then H30 and the eyellipse Z centroid should be located from a point midway

between the full up and full down travel path.
A.4 Axis lengths
A.4.1 X-axis length

In this subclause the term side view axis length refers to the true length of the eyellipse X-axis, not the

horizontal length in side view. Figures A.1 and A.2 illustrate the calculation of side view axis length.

Key
X eyellipse X-axis
1 male centroid
2 female centroid
3 reference centroid
4 rearward

Figure A.1 — Side view location of the male and female eye centroids relative to the reference

centroid
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ISO 4513:2022(E)
Key
L length of eyellipse X-axis
X eyellipse X-axis
1 excluded fraction of males
2 distribution of male eye locations
3 distribution of female eye locations
4 excluded fraction of females
Figure A.2 — Determination of eyellipse X-axis end points and length

The location of drivers' eyes along the side-view axis is related to their stature by a factor of 0,473.

That is, two drivers with stature differing by 10 mm have, on average, eyes located 4,73 mm apart

along the side view axis, with the taller driver rearward. Similarly, two populations with mean stature

differing by 10 mm have, on average, eyellipse centroids located 4,73 mm apart along the side view

axis. Calculation of side view axis length takes into account the eye location distributions of two sub-

populations of each driver population, one for males and one for females. Because males and females

differ in average stature, their distributions also differ in average location along the side view axis.

In addition, the variability of the underlying stature distributions should be taken into account. The

process of determining eyellipse X-axis length involves constructing the population eye location

distribution along that axis and then finding the upper and lower cut-off points that represent the

boundaries of the eyellipse along the side view axis. The underlying distribution of eye locations in side

view is a mixture of two normal distributions, one for males and one for females.

To simplify calculation of the boundaries, the reference eye centroid calculated from Formulae (A.2)

to (A.4) is treated as the zero point along the side view axis, and the boundaries are calculated as

offsets from the reference. First, the centroids of the male and female eye distributions along the side

view eyellipse axis, M and F, respec
...

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