Agent-based modelling of pedestrian movements: the questions that need to be asked and answered

Vulnerable road users have steadily attracted increased importance in transport and planning. The behaviour of pedestrian movements (especially in the areas off but adjacent to roads) requires improved tools to address the issues now being raised. Such behaviour and interactions can now be modelled by using a combination of massively parallel processes simulating individual pedestrians, and a series of behaviours of these simulated pedestrians in the interactions with each other and their environment. The PEDFLOW model has been implemented in the parallel processing language Occam as an agent-based evolutionary system, which allows extensive modelling of detailed pedestrian behaviour with minimal complication. The principles and methodology of its development and application are specified.