ISO 4513:2022

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 2022
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ii
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
Foreword
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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.
iv
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.
v
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.
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.
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
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
L
E right eye
R
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).
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
a
100 to 133 95 173,8 60,3 93,4
a
99 242,1 85,3 132,1
a
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.

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
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.
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
c
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;
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.
1)
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)
xx
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.
EP=−32,5 (7)
ly
EP=+32,5 (8)
ry
EP= (9)
zz
where
P is the x-coordinate of the P point;
x
P is the y-coordinate of the P point;
y
P is the z-coordinate of the P point;
z
E is the x-coordinate for the left and right eye point;
x
E is the z-coordinate for the left and right eye point;
z
E is the y-coordinate of the left eye;
l
E is the y-coordinate of the right eye.
r
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
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
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, respectively, are calculated relative to the reference eye centroid using
Formulae (A.5) and (A.6).
MS=−0,473()S (A.5)
MR
FS=−0,473 S (A.6)
()
FR
where
S is the mean male stature;
M
S is the mean female stature;
F
S is the mean stature of the reference driver population.
R
The standard deviation of each component distribution is calculated using Formulae (A.7) and (A.8).
22 2
σσ=+0,,473 41 87 (A.7)
EM M
22 2
σσ=+0,,473 41 87 (A.8)
EF F
where
σ is the standard deviation of the male eye location distributions along the side view axis;
EM
σ is the standard deviation of the female eye location distributions along the side view axis;
EF
σ is the standard deviation of the male stature distribution;
M
σ is the standard deviation of the female stature distribution.
F
The two means and standard deviations define two overlapping normal distributions along the side
view eyellipse X-axis (see Figure A.2). These may then be used with Formulae (A.9) and (A.10) to
determine lower (forward) and upper (rearward) eyellipse boundaries.
bM− bF−
   
f,c f,c
11−=qp ×ΦΦ+−()p × (A.9)
M   M  
σσ
   
EM EF
bM− bF−
   
re,c re,c
qp=×ΦΦ+−()1 p × (A.10)
   
M M
σσ
 EM   EF 
where
p is the proportion of males in the population;
M
b is the forward boundary of the eyellipse along the side view axis, relative to the reference
f,c
centroid;
b is the rearward boundary of the eyellipse along the side view axis, relative to the reference
re,c
centroid;
q is the eyellipse cut-off percentile;
Φ is the cumulative normal distribution;
M is the mean male eye centroid along the side view axis, relative to the reference centroid;
F is the mean female eye centroid along the side view axis, relative to the reference centroid;
σ is the standard deviation of the male eye location distribution along the side view axis;
EM
σ is the standard deviation of the female eye location distribution along the side view axis.
EF
To find the upper and lower boundaries of the eyellipse along the side view axis, Formulae(A.9) and
(A.10) should be solved iteratively for b and b . Breaking the formula down, the portion inside
f,c re,c
parentheses that appears twice in each formula is the z-score of the lower or upper boundary with
respect to the male or female eye position distribution (along the side view axis). The cumulative
normal distribution returns the proportion of the distribution that lies below (forward) of the upper or
lower boundary. In Formula (A.9), for example, there is an expression for the proportion of the female
population whose eyes lie below the lower cut-off, and an expression for the proportion of the male
population whose eyes lie below the lower cut-off. These proportions are then combined in a weighted
average based on the relative proportions of males and females in the driver population.
The last step is to compute the X-axis length, X , which is simply the difference between b and b .
a_l re,c f,c
Xb=−b (A.11)
a_lre,cf,c
where
b is the forward boundary of the eyellipse along the side view axis, relative to the reference
f,c
centroid;
b is the rearward boundary of the eyellipse along the side view axis, relative to the reference
re,c
centroid.
A.4.2 Y- and Z-axis lengths
Since stature distribution does not affect axis length along the other two axes, their calculation is
relatively simple. The only variable is the eyellipse cut-off percentile. The distributions along these
two axes are modelled as single normal distributions with fixed standard deviations. Finding the axis
endpoints is simply a matter of using the inverse normal cumulative distribution to solve for the cut-off
points that exclude the appropriate proportion of the population. Formulae (A.12) and (A.13) contain
the specific formulae.
−−11
 
Yq=×18,34 ΦΦ−−1 q (A.12)
() ()
a_l
 
−−11
 
Zq=×28,39 ΦΦ()−−()1 q (A.13)
a_l
 
where
q is the eyellipse cut-off percentile;
−1
Φ is the inverse cumulative normal distribution.
A.5 Final centroid location
The forward and rearward boundaries of the eyellipse X-axis were computed relative to the eyellipse
reference centroid. The boundaries may not be symmetrical around the reference centroid location.
Thus, the final centroid should be computed according to Formulae (A.14) to (A.16). These formulae
place the final centroid in vehicle grid at the midpoint between the two side view axis cut-off points and
along the centreline of occupant.
bb+
f,cre,c
XX=+ ×cos β (A.14)
ccref
YY= (A.15)
ccref
bb+
f,cre,c
ZZ=+ ×sin β (A.16)
ccref
where
b is the forward boundary of the eyellipse along the side view axis, relative to the reference
f, c
centroid;
b is the rearward boundary of the eyellipse along the side view axis, relative to the reference
re, c
centroid.
A.6 Eyellipses for selected world populations
Stature values given in Table A.1 may be used to construct eyellipses for the specified populations by
using the formulae given in this annex.
CAUTION — These eyellipses have not been verified by field testing.
Table A.1 — Population anthropometry
Dimensions in millimetres
Standard deviation
Country Gender Mean stature Mean seated height
of stature
USA (reference) Males 1 755 74,2 922,1
Females 1 618 68,7 859,7
Japan Males 1 672,7 62,4 901,3
Females 1 544,8 61,2 838,4
Netherlands Males 1 806,2 80 944
Females 1 690 70 887
NOTE   Data for Japan supplied by Toyota; data for Netherlands supplied by TNO; data for USA from Reference [17].
A.6.1 Axis lengths
Eyellipse axis lengths for a driver population consisting of an equal number of males and females, and a
seat track length >133 mm, are given in Table A.2.
Table A.2 — Left and right eyellipse axis lengths
X-axis length Y-axis length Z-axis length
Country Percentile
mm mm mm
Japan 95 195,1 60,3 93,4
99 271,5 85,3 132,1
Netherlands 95 202,0 60,3 93,4
99 283,1 85,3 132,1
Reference (Table 1) 95 206,4 60,3 93,4
99 287,1 85,3 132,1
NOTE   The difference in X-axis lengths among the reference population, Japanese and Dutch populations is very small,
indicating that the 95th or 99th percentile eyellipses given in Table 2 are sufficient for most design purposes.
A.6.2 Centroid location
Compared to North American and European populations, Japanese are shorter in average stature and
have a larger average ratio of sitting height to stature. These anthropometric differences likely require
an adjustment to the location of their eyellipse centroid. Testing with Japanese drivers is necessary to
derive or validate a formula for locating the centroid.
Similarly, because the Dutch population is taller on average than the reference (USA) population,
resulting in higher seated eye heights, a different formula for locating the eyellipse centroid may also be
needed for that population.
One approach, based strictly on anthropometry, is to adjust the eyellipse centroid Z value (from SgRP)
proportionate to the ratio of average seated heights of the target country's population to seated heights
of the reference population, as follows:
h
T
ZH=+H +638 (A.17)
cref 830
h
R
where
H is the z-coordinate of the AHP (H );
8 8
H is the z distance of the SgRP from the AHP (H );
30 30
h is the target population mean seated height;
T
h is the reference population mean seated height.
R
Adjust the eyellipse centroid X value from the BOFRP using Formula (A.5) (which is based on the
difference between average stature of the target population and average stature of the reference
population), as follows:
XL=−12,,5tL++()664 0 587 −0,,176HS+−0 473()S cos β (A.18)
cref 16 30 TR
where
L is the x-coordinate of the BOFRP (L );
1 1
t is the transmission type (1 with clutch pedal, 0 without clutch pedal);
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
S is the target population mean stature;
T
S is the reference population mean stature.
R
Table A.3 gives the adjustments in centroid location from the reference centroid for a population having
an equal mix of males and females, using anthropometry values from Table A.1 and Formulae (A.17)
and (A.18).
Table A.3 — Change in eyellipse centroid location (50 % male population)
Dimensions in millimetres
Country X Y Z
Japan −37 0 −15
Netherlands 29 0 18
NOTE  Positive numbers are rearward and up from reference centroid.
Annex B
(informative)
Fixed seat 95th and 99th percentile tangent cut-off eyellipses for
an adult population at a 50/50 gender mix
B.1 Background
Fixed seat eyellipses apply to seated positions with no H-point or torso angle adjustment. The eyellipse
centroid is located relative to the fixed seat H-point (SgRP). The only vehicle factor affecting location
of the fixed seat eyellipse is the torso angle, A . Other seat adjustments are assumed fixed at the
manufacturer's design specifications.
These eyellipses are based on the user populations described in Table 1. The 95th and 99th percentile
eyellipses are constructed from tables and equations described in B.2 and B.3. Fixed seat eyellipses for
other percentile tangent cut-offs and gender mixes can be calculated using procedures in Annex C.
Key
X eyellipse X-axis 1 zero X grid
Z H-point to eye line (eyellipse Z-axis) 2 zero Y grid
δ angle of the eyellipse Z-axis from vertical 3 zero Z grid
X x-coordinate of the eyellipse centroid location 4 torso line
c
Y mid-eye y coordinate
cycl
Z z-coordinate of the eyellipse centroid location
c
Figure B.1 — Fixed seat eyellipse side view axis angle and centroid location
B.2 Axis angles
B.2.1 Plan and rear view axis angles
The eyellipse is aligned with the vehicle axes in plan view (Z-plane) and rear view (X-plane).
B.2.2 Side view axis angle
Unlike the adjustable seat eyellipse, the longer primary axis of the fixed seat eyellipse is the Z-axis.
This primary Z-axis is tilted back from vertical along a line from the centroid to the H-point called the
“H-point to eye line”. The side view angle of the eyellipse Z-axis, positive, tipped back at the top from
vertical, δ, in degrees, depends on the torso angle (see Formula B.1 and Figure B.1).
δ =×0,,698 A −909 (B.1)
where A is the torso angle (A40).
NOTE The dimension code for torso angle depends on the passenger seat position under study. A40-2 refers
to passenger second row seating and A40-3 refers to passenger third row seating as defined in SAE J1100.
B.3 Axis lengths
Axis lengths are shown in Figure B.2 and listed in Table B.1.
Table B.1 — Fixed seat eyellipse axis lengths
X-axis length Y-axis length Z-axis length
Percentile
mm mm mm
95 93,5 104,1 130,7
99 132,3 147,3 179,0
a) Plan view
b) Side view c) Rear view
Key
X X-axis length
a_l
Y Y-axis length
a_l
Z Z-axis length
a_l
Figure B.2 — Fixed seat tangent cut-off eyellipse for one eye — True views
B.4 Centroid location
B.4.1 Locating formulae
Formulae (B.2), (B.3), and (B.4) are used to calculate the eyellipse centroid location. Laterally, the
cyclopean (mid-eye) location, Y , is at W20, which normally coincides with the seat centreline (see
cycl
Figure B.1). In side view the centroid is located to vehicle grid using L31 for SgRP x-coordinate and H70
for SgRP z-coordinate.
XL=+619×sin δ (B.2)
c 31
YW= (B.3)
cycl 20
ZH=+619×cos δ (B.4)
c 70
where
L is the SgRP x-coordinate (L );
31 31
W is the SgRP y-coordinate (W );
20 20
H is the SgRP z-coordinate (H );
70 70
δ is the side view angle of the eyellipse Z-axis, in degrees (positive, tipped back at the top
from vertical).
NOTE The dimension codes selected for SgRP coordinates (to grid) depend on passenger seat position under
study: L31-2, W20-2 and H70-2 refer to second row passenger seating; L31-3, W20-3, and H70-3 refer to third
row passenger seating.
B.4.2 Left and right centroids
The left and right eyellipse centroids are 65 mm apart, 32,5 mm either side of the mid-eye location.
B.5 Seats with limited H-point adjustment
If a second or succeeding row seat has fore and aft H-point adjustment, with a back angle that is either
fixed or adjustable, there are no field data available on which to base a procedure for selecting or
locating an eyellipse. Until such data are available, select the 95 % fixed seat eyellipse, locate it from
the manufacturer's SgRP and torso angle, and then sweep the eyellipse along the range of normal
riding fore and aft seat adjustment. The swept volume defines the range of rider eye locations. If the
manufacturer's SgRP or torso angle is unknown, use the rearmost, lowest normal riding position and a
torso angle of 25°.
Annex C
(informative)
Fixed seat tangent cut-off eyellipses for any user population
stature distribution and gender mix
C.1 General
Fixed seat eyellipses should be calculated from equations given in this annex when the user population
is different from the reference population listed in Table 1, because the underlying stature distribution
is different, the gender mix is different, or a unique cut-off contour is needed.
C.2 Axis angles
C.2.1 Plan and rear view 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).
C.2.2 Side view angle
The side view angle of the eyellipse Z-axis (positive, tipped back at the top from vertical), δ, in degrees,
depends on the torso angle (see Figure B.1):
δ =×0,,698 A −909 (C.1)
where A is the torso angle (A40).
C.3 Axis lengths
C.3.1 Eyellipse Z-axis length
The following calculations are required to determine the Z-axis length.
C.3.1.1 Mean male and female H-point-to-eye distances
These values are calculated from the mean statures for the selected male and female population.
Formulae (C.2) and (C.3) are used to calculate the H-point-to-eye distance.
h = 67,0 + 0,351 S – 1,613 A (C.2)
M M 40
h = 67,0 + 0,351 S – 1,613 A (C.3)
F F 40
where
S is the mean population stature for males;
M
S is the mean population stature for females;
F
h is the mean H-point-to-eye distance for males;
M
...