french institute of science and technology for transport ... - Ifsttar

2_SCIENTIFIC AND TECHNICAL ACTIVITIES
Trams and road users
A dangerous mix?
The tram networks that are springing up in more and
more cities on the grounds of sustainable development
have a drawback − an increasing number of collisions
between trams and other road users.
Two studies which were financed by the DGITM and
completed in 2011 have examined the interactions between
road users and trams, from the standpoint of tram drivers
(Study 1) and of road users (Study 2). They both make recommendations
for improving safety.
The main difficulties encountered by the tram drivers are due
to antisocial behaviour, a failure to comply with regulations
and poor concentration on the part of the other road users
(motorists, pedestrians, the users of 50 cm 3 motorized twowheelers
and cyclists).
In addition, 19% of road users are unaware of the priority rule
for trams and do not see them as a potential danger due their
low speed. This could partly explain their risky behaviour at
locations of interaction with trams.
The situation calls for increased communication about the
regulations that apply to tramways. In addition, an action plan
that sets out to modify attitudes and subjective norms would
be helpful. More broadly, in the current economic and financial
crisis, it is essential to examine the collective dimension of
safety and the energy-related and social implications of urban
public transport policies.
@ CONTACTS
patricia.delhomme@ifsttar.fr & françoise.paran@ifsttar.fr
a
b
a. A tram with priority.
b. A wrong-way vehicle
on the left.
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d’infos
Find out more about
the MOCoPo research
programme at
http://mocopo.ifsttar.fr/
One of the zones on
the N87 where a
helicopter was used
to measure vehicle
trajectories.
MOCoPo
Traffic under surveillance
How can we forecast traffic congestion on motorways
and measure how it will affect the level of pollution?
This is the topic covered by the three-year PREDIT-funded
MOCoPo (1) research programme which got under way
in 2011.
The first year of research has been devoted to collecting
a large amount of data in the area near a highly congested
motorway (the N87) in the Grenoble region. Pollution and extremely
detailed traffic data were collected.
In order to measure the traffic, a helicopter was positioned for
one hour above three zones on the N87 on five consecutive
days. The resulting 15 hours of footage are currently being
processed by software developed by the Delft University of
Technology in the Netherlands. This outputs the longitudinal
and lateral positions of all the vehicles on the lane more than
20 times a second by reidentifying vehicle trajectories over a
(1) Measuring and Modelling Congestion and Pollution.
length of 500m. The resulting data can be used to analyze car
following behaviours, lane changes, acceleration and deceleration,
none of which are accessible from conventional spot
measurements.
The pollution measurements were also highly sophisticated,
combining very detailed knowledge of the vehicle fleet with
knowledge of the emissions during fifteen days in each of the
seasons at three points on the ring road with differing congestion
levels.
2012 and 2013 will be spent validating and improving our
congestion and pollution forecasting models. The project will
end with the drafting of a series of recommendations for minimizing
the possible adverse impacts (delays, pollutant emissions,
safety problems) of traffic on high speed urban roads.
@ CONTACT
christine.buisson@ifsttar.fr
ifsttar French Institute of Science and Technology for Transport, Development and Networks