ISO 15623:2013

INTERNATIONAL ISO
STANDARD 15623
Second edition
2013-07-15
Intelligent transport systems —
Forward vehicle collision warning
systems — Performance requirements
and test procedures
Systèmes intelligents de transport — Systèmes d’avertissement
de collision frontale du véhicule — Exigences de performance et
modes opératoires
Reference number
©
ISO 2013
© ISO 2013
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ii © ISO 2013 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 4
5 Specifications and requirements. 5
5.1 System functionality . 5
5.2 Necessary functions . 5
5.3 Operating model . 5
5.4 Warning functionality . 6
5.5 Warning elements requirements . 7
5.6 System Classification . 9
5.7 Obstacle vehicle detection area and performance .10
5.8 FVCWS performance on curves .11
5.9 User safety requirements .12
5.10 Human interface requirements .12
5.11 Awareness of system limitations .13
6 Evaluation test method for measuring detection performance .13
6.1 Test target specification .13
6.2 Environmental conditions .13
6.3 Test method for detection zone .13
6.4 Test method for warning distance range and accuracy .14
6.5 Test method for target discrimination ability .15
Annex A (informative) Basic consideration of collision warning .18
Annex B (informative) Obstacle detection along curves .23
Annex C (informative) Laser radar — Coefficient of test target .25
Annex D (informative) Radio wave radar test target geometry .29
Bibliography .30
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. 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. 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.
The committee responsible for this document is ISO/TC 204, Intelligent transport systems.
This second edition cancels and replaces the first edition (15623:2002), which has been technically revised.
iv © ISO 2013 – All rights reserved

Introduction
The main system function of a forward vehicle collision warning system (FVCWS) is to warn the driver
when the subject vehicle encounters the situation of a forward vehicle in the subject vehicle’s trajectory
becoming a potential hazard. This is done by using information such as: (1) the range to forward vehicles,
(2) the relative velocity of the forward vehicles with respect to subject vehicle and (3) whether a forward
vehicle is in the subject vehicle trajectory. Based upon the information acquired, the controller identified
as “FVCWS target selection and warning strategy” in Figure 1 produces the warning to the driver.
Figure 1 — Functional forward vehicle collision warning system’s elements
Automobile manufacturers and component suppliers throughout the world have been vigorously
pursuing the development and commercialisation of these FVCWS systems. Systems of this type have
already been introduced on to the market in some countries. Thus the standardization efforts began
in 1994 amongst interested countries. This International Standard is composed to address only the
basic performance requirements and test procedures for the FVCWS type systems. This International
Standard may be used as a basis by other standards for systems which have more features and may
extend beyond this International Standard.
INTERNATIONAL STANDARD ISO 15623:2013(E)
Intelligent transport systems — Forward vehicle
collision warning systems — Performance requirements
and test procedures
1 Scope
This International Standard specifies performance requirements and test procedures for systems
capable of warning the driver of a potential rear-end collision with other vehicles ahead of the subject
vehicle while it is operating at ordinary speed. The FVCWS operate in specified subject vehicle speed
range, road curvature range and target vehicle types. This International Standard covers operations
on roads with curve radii over 125 m, and motor vehicle including cars, trucks, buses, and motorcycles.
Responsibility for the safe operation of the vehicle remains with the driver.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
IEC 825-1:1993, Safety of laser products — Part 1: Equipment classification, requirements and user’s guide
(includes update of 1994)
3 Terms and definitions
For the purpose of this document, the following terms and definitions apply.
3.1
collision warning
information that the system gives to the driver indicating the need for urgent action to avoid or reduce
the severity of a potential rear end collision with another forward vehicle
Note 1 to entry: This warning is issued in the advanced stages of a dangerous situation to warn the driver of the
need to perform emergency braking, lane changing or other emergency manoeuvres in order to avoid a collision.
3.2
reflection coefficient of test target
RCTT
optical radar reflectivity of the target, which is defined as the radiated intensity towards the receiver (Iref
- W/sr) measured at target level, immediately after the reflection; divided by the intensity of irradiation
received from the transmitter (Et - W/m ) measured at target level, immediately before the reflection
Note 1 to entry: The units for RCTT value are in m /sr (see Annex C).
3.3
forward vehicle
vehicle in front of and moving in the same direction and travelling on the same roadway as the subject vehicle
3.4
forward vehicle collision warning system
FVCWS
system capable of warning the driver of a potential collision with another forward vehicle in the forward
path of the subject vehicle
3.5
obstacle vehicles
vehicles, both moving and stationary, considered potential hazards that can be detected by this system
EXAMPLE Motor vehicles only, that is cars, trucks, buses, and motorcycles.
3.6
preliminary collision warning
information that the system gives to the driver in the early stages of a potentially dangerous situation
that may result in a rear end collision.
Note 1 to entry: The system may provide this warning prior to the collision warning.
3.7
radar cross section
RCS
measure of the reflective strength of a radar target measured in square meters, and defined as 4π times
the ratio of the power per unit solid angle scattered in a specified direction to the power per unit area in
a radio wave incident on the scatterer from a specified direction
3.8
visibility
distance which the illuminance of a non-diffusive beam of white light with the colour temperature of
2700 K is decreased to 5 % of its original light source illuminance
3.9
adaptive Cruise Control
ACC
enhancement to conventional cruise control systems which allows the subject vehicle to follow a forward
vehicle at an appropriate distance by controlling the engine and/or power train and optionally the brake
Note 1 to entry: See ISO 15622.
3.10
adjacent lane
lane of travel sharing one lane boundary with the lane in which the subject vehicle is traveling and
having the same direction of travel as the subject vehicle lane
3.11
clearance
x (t)
c
distance x (t) from the target vehicle trailing surface to the subject vehicle leading surface
c
x (t)
c
3.12
cut-in vehicle
forward adjacent vehicle that has a lateral component of motion towards the path of the subject vehicle
3.13
jerk
third derivative with respect to time of the position of an object; equivalently the rate of change of the
acceleration of an object; considered a measure of harshness of vehicle motion
3.14
minimum velocity
V )
min
minimum subject vehicle (SV) speed for which the FVCWS must be capable of initiating a warning
2 © ISO 2013 – All rights reserved

3.15
rear-end collision
forward vehicle collision in which the front of the subject vehicle strikes the rear of the forward vehicle
3.16
relative velocity
v (t)
r
difference between the longitudinal velocities of the subject vehicle (SV) and
...