Numerical study of an informative motorway traffic control system.
Proceedings of the 5th IMA Conference on Mathematics in Transport.
The Institute of Mathematics and its Applications
The paper studies qualitative properties of reactive and predictive informative control applied to a simple 2 element network. The model includes two links of different length with identical constant-flow in-ramps acting as bottlenecks. A simple relation is used for modelling drivers reaction on travel time information. Actual travel time, frozen-field travel time and modelled travel time with fixed link demand are calculated. A first order continuous traffic flow model (LWR model) is used for modelling network links and for the simulating module of a predictive control system. A second-order numerical scheme with fine temporal and spatial discretization is used to model the actual network and a first-order scheme with much larger time and space steps for the modelling block. It is demonstrated that the control based on frozen-field travel time estimates leads to long-period flow oscillations with re-appearing traffic congestions in front of bottlenecks. Application of predictive control solves this problem. However the system still exhibit oscillations which period approximately equals to the delay between starting modelling and releasing travel time information.
|Title:||Numerical study of an informative motorway traffic control system|
|Event:||5th IMA Conference on Mathematics in Transport|
|Dates:||2010-04-12 - 2010-04-14|
|UCL classification:||UCL > School of BEAMS
UCL > School of BEAMS > Faculty of Engineering Science
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