This paper describes the KNOSIMO simulation model, developed on behalf of the West German Ministry of Transport, which makes it possible to model the traffic flow at unsignalized intersections on a personal computer. Its traffic flow simulation is based on a microscopic event-oriented approach; the elements of the model are the individual vehicles taking certain actions at certain events. The vehicle headways in the model have a Hyper-ERLANG-Distribution, to represent the occurrence of vehicle platoons, and the behaviour of individual vehicles is described in terms of their critical gaps and move-up times. The KNOSIMO program is written in PASCAL, and has different versions for different personal computer systems; its data is input through an interactive dialogue, directed by a menu of choices, where the user is asked to enter various characteristics of the traffic. The results are presented as the means and standard deviations of various delay and congestion quantities for all traffic streams in all time intervals, together with various other statistics of these quantities. The model can be applied to both urban and rural intersections with priority controlled according to specific West German road traffic regulations. The results of the simulation usually agree well with those of corresponding theoretical and empirical studies. As KNOSIMO realistically describes the traffic conditions at unsignalized intersections, it can support the design of existing and new intersections, together with decisions about the necessity of traffic signals.
Abstract