ISO 4513:2010

INTERNATIONAL ISO
STANDARD 4513
Third edition
2010-05-15

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 4513:2010(E)
©
ISO 2010

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ISO 4513:2010(E)
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ISO 4513:2010(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.5
4.3.1 Rear and plan view angles.5
4.3.2 Side view angle, β.6
4.4 Centroid locations .6
4.4.1 Locating equations.6
4.4.2 Seats with vertical adjustment.6
4.4.3 Left, right, mid-eye centroids .7
5 Eyellipse locating procedure, Class A vehicles.7
6 Neck pivot (P) and eye (E) points: locating procedure, Class A vehicles .8
6.1 Background.8
6.2 Neck pivot (P) points.8
6.3 Eye (E) points.9
Annex A (informative) Adjustable seat tangent cut-off eyellipses for any user population stature
distribution and gender mix .10
Annex B (informative) Fixed seat 95th and 99th percentile tangent cut-off eyellipses for an adult
population at a 50/50 gender mix.17
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 International Standard .32
Bibliography.34

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ISO 4513:2010(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.
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 4513 was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 17, Visibility.
This third edition cancels and replaces the second edition (ISO 4513:2003), which has been technically
revised.
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ISO 4513:2010(E)
Introduction
This International Standard 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 International Standard;
h) neck pivot (P) and eye (E) points are based on the previous plan view sight lines to rearview 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 equations 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).

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INTERNATIONAL STANDARD ISO 4513:2010(E)

Road vehicles — Visibility — Method for establishment of
eyellipses for driver's eye location
1 Scope
This International Standard 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 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 International Standard 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 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 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 following terms given in ISO 6549 apply:
a) H-point;
b) seating reference point, SgRP.
For the purposes of this document the following terms given in SAE J1100 apply:
1) ball of foot reference point (BOFRP);
2) accelerator heel point (AHP);
NOTE For applications using the H-point machine described in ISO 6549, the term “operator heel point” is used
instead of “accelerator heel point”.
3) Class A and Class B vehicles;
4) H-point travel path, TL23, TH21;
5) A19 — Seat track rise;
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ISO 4513:2010(E)
6) H30 — Seat height;
7) L6 — Ball of foot reference point (BOFRP) to steering wheel centre.
For the purposes of this document the following definitions apply.
3.1
eyellipse
contraction of the words “eye” and “ellipse” used to describe the statistical distribution of eye locations in
three-dimensional space located relative to defined vehicle interior reference points
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
cyclopean eye point
mid-eye point
midpoint between left and right eye points or left and right eyellipse centroids at centreline of occupant
3.3
tangent cut-off plane
plane tangent to an eyellipse
NOTE 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
See Annex D.
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ISO 4513:2010(E)
3.5
neck pivot point
P point
point about which a driver's head turns on a horizontal plane
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
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 rearview mirrors
located to the left and right of the driver
See Figure 2.
Dimensions in millimetres


a)  Plan view
Key
b)  Side view
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 4513:2010(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
See Figure 3.
Dimensions in millimetres


a)  Plan view b)  Side view
Key
E left eye 1 driver head centreline
L
E right eye 2 line, viewed end on, between E and E
R L R
P neck pivot point
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
Gender Mean stature Standard deviation of 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
equations given in 4.2 to 4.3.2. These eyellipses are applicable to driver and front outboard passenger seat
locations.
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ISO 4513:2010(E)
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
Z Z-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).
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ISO 4513:2010(E)
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 equations
Equations (2) to (5) are used to calculate the eyellipse centroid location (see Figure 5).
X = L1 + 664 + 0,587 L6−−0,176 H30 12,5 t (2)
c
Y=W20 −32,5 (3)
cL
Y=W20 +32,5 (4)
cR
Z = H8 + 638 + H30 (5)
c
where
L1 is the x-coordinate of the BOFRP;
L6 is the x distance from the steering wheel centre to the BOFRP;
H30 is the z distance of the SgRP from the AHP;
t is the transmission type (1 with clutch pedal, 0 without clutch pedal);
W20 is the y-coordinate of the SgRP;
H8 is the z-coordinate of the AHP.
4.4.2 Seats with vertical adjustment
For driver seats having vertical adjustment, Equations (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 Equation (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 4513:2010(E)

Key
A19 seat track rise TL23 seat track travel
AHP accelerator heel point W20 y-coordinate of the SgRP
BOFRP ball of foot reference point X x-coordinate of the eyellipse centroid location
c
H8 z-coordinate of the AHP Y mid-eye y-coordinate
cycl
H30 z distance of the SgRP from the AHP Z z-coordinate of the eyellipse centroid location
c
L1 x-coordinate of the BOFRP β side view angle
L6 x distance from the steering wheel centre to BOFRP 1 zero X grid
L31 x-coordinate of the SgRP 2 zero Y grid
SgRP seating reference point 3 zero Z grid
TH21 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 4513:2010(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 Equations (2) to (5);
f) tilt the front of the eyellipse X-axis down in side view according to Equation (1).
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 Equations (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 X Y Y Z

(TL23) (P points) (Left-hand drive) (Right-hand drive)
>133 P1 0 −7,3 +7,3 −20,5
P2 26,2
>133 +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
P2 39,2
<133 +20,6 −20,6 −20,5
P3 175,0
<133 −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.

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 4513:2010(E)
6.3 Eye (E) points
Position the eye (E) points relative to the P points as shown in Figure 3 and the following equations:
EP=−98 (6)
xx
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

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ISO 4513:2010(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 equations 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 Equation (A.1) (see Figure 5).
β=−18,6 A19 (A.1)
where A19 is the seat track rise angle.
A.3 Reference centroid location
A.3.1 Locating equations
The reference centroid for the normative part of this International Standard, calculated using Equations (A.2)
to (A.4), is based on a driver population defined by NHANES III anthropometry (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 equations for other national driver populations.
X =+L1 664+ 0,587 L6− 0,176 H30− 12,5 t (A.2)
cref
YW=20 (A.3)
cref
ZH=+8638+H30 (A.4)
cref
where
L1 is the x-coordinate of the BOFRP;
L6 is the x distance from the steering wheel centre to the BOFRP;
W20 is the y-coordinate of the SgRP;
H8 is the z-coordinate of the AHP;
H30 is the z distance of the SgRP from the AHP;
t is the transmission type (1 with clutch pedal, 0 without clutch pedal).
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ISO 4513:2010(E)
A.3.2 Seats with vertical adjustment
For driver seats having vertical adjustment, Equations (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 section 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
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ISO 4513:2010(E)
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 Equations (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 Equations (A.5) and (A.6).
M0=−,473S S (A.5)
()
MR
F=−0,473 S 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 Equations (A.7) and (A.8).
22 2
σ= 0,473 σ + 41,87 (A.7)
EM M
22 2
σ= 0,473 σ + 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 Equations (A.9) and (A.10) to determine lower
(forward) and upper (rearward) eyellipse boundaries.
⎛⎞ ⎛ ⎞
CF−−M CF F
1q− =p ×Φ +1−p ×Φ (A.9)
()
⎜⎟ ⎜ ⎟
MM
σσ
⎝⎠EM ⎝ EF⎠
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ISO 4513:2010(E)
⎛⎞ ⎛ ⎞
CM−−M CM F
qp=×Φ +1−p ×Φ (A.10)
⎜⎟()⎜ ⎟
MM
σσ
EM EF
⎝⎠ ⎝ ⎠
where
p is the proportion of males in the population;
M
CF is the forward boundary of the eyellipse along the side view axis, relative to the reference centroid;
CM is the rearward bound
...