Brief Instructions

To construct barriers to simulate weaving and so on, do the following: click and hold mouse button down while moving mouse on roadway. Release the button when you are happy with the region chosen. This highlighted rectangular area can have its max speed modified or have barriers erected along any of its four edges. Properly constructed barriers can simulate roadway accidents, merging on- or off-ramps and so on.

Detailed Instructions and Examples

More detailed directions on constructing roadways are given on this page.

Vehicles are color coded by lane of destination so that weaving rules can be observed. At higher volumes, note that vehicles occasionally give up and travel to a wrong destination.

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Note: "Simulation Speed" on the button just above adjusts the rate at which simulation time steps proceed in actual time. This does not affect roadway speed limits. Roadway speed limits can be adjusted as explained on the examples page.


When developing this simulator, we referenced that found in the web site of The program posted on the same site was used for the flow simulation of the two-lane case. We modified the code as described at on this page.