The basic traffic model ruling the movement of vehicles was developed by Rainer Wiedemann in 1974 at Karlsruhe University. It is a car-following model that considers physical and psychological aspects of the drivers. The model underlying pedestrian dynamics is the Social Force Model by Dirk Helbinget al. from 1995. "Microscopic simulation", sometimes called microsimulation, means each entity of reality is simulated individually, i.e. it is represented by a corresponding entity in the simulation, thereby considering all relevant properties. The same holds for the interactions between the entities. The opposite would be a "macroscopic simulation", in which the description of reality is shifted from individuals to "averaged" variables like flow and density. The corresponding product from the same manufacturer is called Visum.
Transport modes
In Vissim the following types of traffic can be simulated, and mutually interact:
In VISSIM, vehicle conflict points can be modelled using Priority Rules, Conflict Areas or Signal Heads. Signals can be modelled with fixed-time plans, or various modules such as VAP are available to model on-demand signals and other types of control and coordination.
Versions and associated files
Versions up to 5.40 created.INP files which used a proprietary language. Versions 6 and later created.INPX files which use an XML-based language. Both produce human-readable code:
.INP example
CONNECTOR 10011 NAME "West Road" LABEL 0.00 0.00 FROM LINK 30 LANES 1 AT 34.905 OVER 574805 165119 0.00000 OVER 574805 165119 0.000 OVER 574805 165120 0.000 OVER 574805 165120 0.000 TO LINK 2 LANES 1 AT 0.358 BEHAVIORTYPE 1 DISPLAYTYPE 1 ALL DX_EMERG_STOP 5.000 DX_LANE_CHANGE 200.000 GRADIENT 0.00000 COST 0.00000 SURCHARGE 0.00000 SURCHARGE 0.00000 SEGMENT LENGTH 10.000 ANIMATION
.INPX example
Further Literature
R. Wiedemann, Modelling of RTI-Elements on multi-lane roads. In: Advanced Telematics in Road Transport edited by the Commission of the European Community, DG XIII, Brussels, 1991.
M. Fellendorf, VISSIM: A microscopic simulation tool to evaluate actuated signal control including bus priority. 64th ITE Annual Meeting, 1994.
L. Bloomberg and J. Dale, Comparison of VISSIM and CORSIM Traffic Simulation Models on a Congested Network. Transportation Research Record 1727:52-60, 2000.
D. Helbing, I. Farkas, and T. Vicsek, Simulating dynamical features of escape panic. Nature, 407:487–490, 2000.
M. Fellendorf and P. Vortisch, Validation of the microscopic traffic flow model VISSIM in different real-world situations. Transportation Research Board, 2001.
D. Helbing, I.J. Farkas, P. Molnar, and T. Vicsek, Simulation of Pedestrian Crowds in Normal and Evacuation Situations. In Schreckenberg and Sharma editors. Pedestrian and Evacuation Dynamics, Duisburg, 2002. Springer-Verlag Berlin Heidelberg.
B.B. Park and J.D. Schneeberger, Microscopic Simulation Model Calibration and Validation: Case Study of VISSIM Simulation Model for a Coordinated Actuated Signal System. Transportation Research Record 1856:185-192, 2003.
G. Gomes, A. May, and R. Horowitz, Congested Freeway Microsimulation Model Using VISSIM. Transportation Research Record 1876:71-81, 2004.
R. Jagannathan and J.G. Bared, Design and Operational Performance of Crossover Displaced Left-Turn Intersections Transportation Research Record 1881:1-10, 2004.
M.M. Ishaque and R.B. Noland, Trade-offs between vehicular and pedestrian traffic using micro-simulation methods. Transport Policy 14:124-138, 2007.
W. Burghout, J. Wahlstedt, Hybrid Traffic Simulation with Adaptive Signal Control Transportation Research Record 1999:191-197, 2007.
A. Johansson, D. Helbing, and P.K. Shukla, Specification of the Social Force Pedestrian Model by Evolutionary Adjustment to Video Tracking Data. Advances in Complex Systems 10:271–288, 2007.