Pedestrian simulation models are generally described as agent based computational models for simulating the actions and interactions of autonomous individuals with a view to assessing their effects on the system as a whole.
Agent based modelling mimics the simultaneous operations of multiple agents in an attempt to re-create and predict the actions of complex phenomena. The process is one of emergence from the lower (micro) level of agents to a higher (macro) level system. As such, a key notion is that simple behavioral rules generate complex behavior; that the whole is greater than the sum of the parts.
Each agent in a model will typically have a range of physical attributes for example size and desired walking speed. In addition each agent will maintain a range of behavioral characteristics that may change as they move through the model space for example ultimate destination point, aversion to local obstacles, pull towards intermediate points along their journey etc. Finally the space that agents move through will have a number of characteristics i.e. areas of free flow space and areas which contain obstacles that agents must navigate around. The combination of the agents physical characteristics, behavioral rules and goals and the restrictions placed on the agents by the space they move through combine to produce the “system” or model as a whole.
Pedestrian models are an important tool in assessing the efficiency and safety of pedestrian facilities and urban spaces and form an integral part in the planning and design of modern cities and the structures within. Typical output from a pedestrian model will include measures of how easy or difficult it is for people to move through different areas of space, be it a complex internal structure or an open plan urban space. In addition many standardised metrics are available to inform model builders on the “quality of experience” that people are receiving from the space they move through, for example areas of high density, packing, frustration, delay and the potential for crushing or safety concerns.
Lastly, pedestrian simulation models can be used to assess the interactions between people and traffic in urban areas focusing on safety prevention and accident analysis.