A recursive method for traffic management through a complex path network

Many simulation models contain one or more transport systems where some type of vehicle, perhaps an AGV, a fork truck, a shuttle, or a human being, travel along predefined paths. Locations along the paths may specify where loads carried by the vehicle transfer to or from it, where some activity takes place requiring the vehicle\´s presence, or where vehicle routing logic executes. This paper focuses on the last topic, the routing of vehicles along a path system where alternate paths exist and path selection is determined at so called "routing nodes" based on a dynamic analysis of traffic congestion along each possible route towards some destination. Other routing nodes further along each path present more combinations of possible interim paths. A recursive search algorithm is presented to iteratively evaluate each possible route when a vehicle encounters a routing node. The vehicle is directed along a path with the least overall congestion towards its destination. A sample model demonstrating this algorithm implemented in the AutoMod software is used for illustration. Other simulation products may have the features to support this type of vehicle routing control algorithm.