PRIORITIES FOR EU MOTOR VEHICLE SAFETY DESIGN

esponse was generally favourable, and users were particularly positive about the potential
for the prevention of theft and unauthorised driving. Some reliability issues were raised by
the study, but the conclusion was that these could be solved with a different type of smart
card. Further trials with the alcohol interlock are planned. It has yet to be established
whether such systems would be accepted by non-offenders.
Recommendations
• Further work is required to develop practical systems and to understand their
effectiveness and acceptability
• Consideration should be given to developing such systems in combination with an
electronic driving licence system.
(e) Collision avoidance systems
Research on collision warning and collision avoidance systems is taking place in Japan, the
United States and Europe. Very large estimates of the safety potential of such systems have
been claimed but there are a lot of difficulties in many of the concepts for collision warning
and avoidance, both in technical and in behavioural terms. Most of the proposed systems
require a well controlled traffic situation, such as that found on motorways, to be practical. To
be effective in addressing significant accident problems, consideration needs to be given to
extending the systems to work on urban and rural, non-motorway roads. In considering
collision avoidance systems, it is important to be aware of possible driver behaviour
adaptation. Such adaptation may negate some of the effectiveness.
Forward collision avoidance: Systems that apply the brakes automatically may avoid some of
the problems caused by long driver reaction times.
Lane-change warning: Times to collision in safety-critical lane changes are normally much
less than one second. Since mean driver reaction time is about one second, there is not
sufficient time for a driver to respond to a warning before crashing. Because there is
insufficient time for reaction to a warning, lane change and merging crashes can probably
only be avoided by intervening systems. But these have their own problems: how to detect
driver intentions and how to intervene. This may be by taking over the steering from the
driver or by providing feedback through the steering wheel.
The technical and operational feasibility of such systems has still to be demonstrated and
there is a long way to go before collision avoidance systems could offer an effective route to
safety improvement.
(f) Anti-lock braking systems
The most widely used driver assistance system is the anti-lock braking system (ABS) which
is now fitted to many new cars.
Prospective accident studies suggest that ABS should reduce relevant severe and fatal
accidents by around 5-7%, since the driver is still capable of braking and steering. However,
studies have also indicated that such benefits might be reduced or negated by behavioural
adaptation.
Recommendation
As recommended by ETSC’s last vehicle safety review in 1993, further European research
would help to ascertain whether ABS alone has a role to play in accident reduction.
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