A mesoscopic model of the Aimsun hybrid simulator showing a microscopic pocket of greater detail
Transport and traffic analysis nowadays tends to switch between static analysis modelling for large scale studies and microsimulation for finer grain work, with perhaps the mesoscopic model also finding a place for mid-level. Most producers make software tools at all three levels and increasingly package them together.
Spanish firm TSS (Transport Simulation Systems) has gone one better with its latest release Aimsum 7, by giving it the capacity to "zoom in" from a larger scale mesoscopic model to a smaller area that need microsimulation work, all on the one screen.It calls the concept the "hybrid simulator" which combines an event-based mesoscopic model with a more detailed time-sliced microsimulation.
This marks a sea change in how traffic models will be conceived, the firm claims, declaring that the method means models will not simply be built once and then discarded. "The hybrid makes it possible for the first time to build demand models on a larger and larger scale using a single all-in-one package,” claimed TSS managing director Jaime Ferrer “with no cumbersome manual interfacing between macroscopic and microscopic models and no need to be updating and revising separate models with independent networks and databases."
Another new feature is the FZP exporter, which exports simulations to
