Extending microscopic traffic modelling with the concept of situated agents

In the traffic simulation field, there is a general agreement that microscopic simulation is becoming more viable, improving the way in which system elements are represented. However, even with more powerful computational resources made available trading off between realism and too much abstraction is an important issue to overcome, as traditional micro-simulation approaches still fail to profit from all benefits that realism could offer to traffic modelling. In this work we bring this discussion forward and propose a multi-agent model of the traffic domain where integration is ascribed to the way the environment is represented and in which agents interoperate in microscopic simulations. While most approaches still deal with drivers and vehicles indistinguishably as a single entity, in this work vehicles are merely moveable objects whereas the driving role is played by an agent fully endowed with different cognitive abilities situated in the environment. We start by discussing on the role of the environment dynamics in supporting a truly emergent behaviour of the system, and then on an extension of the traditional carfollowing and lane-change models with the concept of situated agents. A physical communication model is proposed to explore the different perception abilities of each single driver agent as the basis for different interactions and overall system behaviour. Some performance issues are also identified and the result is a more flexible structure that allows for a more realistic representation of drivers’ behaviour in microscopic simulation models.