CTR Research Themes
Dynamic modelling of road traffic
CTR works with microscopic and mesoscopic simulation models of road
driver-vehicle units as well as hybrid combinations of such models. We
have developed microscopic models of Swedish motorway traffic and
calibrated and applied several other microscopic models. Our in-house
mesoscopic simulator MEZZO is the platform applied in several of our
research projects.
Driving behaviour
We have access to the instrumented vehicle from the Traffic and Logistics division, which logs detailed behavior of its
driver and that of other vehicles in front and behind the instrumented
vehicle. Logged data is a basis for development of microscopic
simulation models of driver-vehicle behaviour in relation to other
vehicles.
Driver choice behaviour
Based on Stated Preference interviews and interactive games we model
driver choice of routes and departure times. Of special interest is
driver reactions to information on traffic incidents.
Traffic information and control
Based on traffic simulation and driver choice modelling we study the
effect of traffic information on queue development and dissipation
after incidents.
Effects of ITS
Using microscopic simulation we evaluate effects of Intelligent Traffic
Systems and especially Driver Support such as intelligent speed
adaptation and lane departure warning.
Congestion charging
Stockholm recently introduced a system for congestion charging in the
central area. Before and after studies are used to model impacts on
choice of routes and departure times. Differentiated charges over
locations and time would further impact choice behaviour.
Fuel consumption, emissions and noise from cars depend heavily on interactions in traffic causing braking and accelerations. Microscopic simulation is used to analyse network effects.
Public transport operation
Where public transport operates in mixed traffic it interacts with
other traffic. Mesoscopic simulation is used to study effects of bus
bays, bus lanes, signal priorities and operations strategies on public
transport and on other traffic.
VTI in Linkoping has several advanced moving-base driving simulators. Microscopic traffic simulation is developed to create realistic surrounding traffic in driving sÃmulators.
Data collection, processing and analysis
Our knowledge of traffic behaviour is based on observations collected
by different sensor devices such as inductive loops, radar, cameras
etc. This data needs to be fused and processed to estimate flows, speed
and travel times.
OD estimation
Traffic assignment and studies of alternative routes depends on
knowledge of origins and destinations of vehicles and how they vary
over time of day. So called OD matrices are estimated based on home
surveys and traffic counts.