Cohue Example

These crisis simulation results have been obtained using a simple scenario: a terrorist attack in a train station. Trains run in opposite directions (toward the city or the suburbs). Several ticket offices or vending machines are located in the station. The station has two entrance doors. Agents enter into the station, coming from trains or the outside, then, at each instant, try to satisfy their own motivations.

The figure represents the train station model, with agents trying to satisfy their motivations.The agents colors represent the value of a specific state variable, with a shading from blue to red. For example, the agent motivation is satisfied for agents in blue, not satisfied for agents in red.

Each agent is defined using general motivations and behaviors (such as life-saving motivations and behaviors), depending on stress-related state variables. The station everyday life is modelled by attributing to individuals various motivations related to the chosen scenario. For example: “buying a ticket”, “taking a train”, etc.

DirectIA® allows the emergence of compromise behaviors, when the strengths propagated through each behavioral subgraphs are comparable. For instance, in a normal situation, an agent could wait in a ticket office queue because of a higher motivation for buying a ticket than for taking a train. But if he has a higher motivation to take a train, the agent could then leave the waiting queue in order to run after the current train, which is on his own schedule.

Our scenario defines events that occur at specific times, and thus activate interactive objects in the scene. These objects trigger stimuli, and the agents react to them through an emotional transfer function. For example, when a ticket office opens, this stimulus calms down the people waiting in the queue, by changing their “edginess” state variable.

Depending on the object, the triggered stimulus can be spread over time, and also distance. As a result, it can have an immediate and strong influence on agents close to the object and a delayed and weakened influence on agents further away.

These parameters, the strength of the stimulus, and the impacted area, are specified within the scenario. These stimuli have an influence on the crowd motivations, thus triggering new reactions from agents.

This sequence of images shows the activation of an object, thus propagating a stimulus of danger through the train station. This demonstrates the escape phenomenon of the agents in reaction to this unexpected event.