The pedestrian demand on a site is expressed in terms of the flow of pedestrians between all pairs of origins and destinations (for example, Entrances and Exits or Populated Zones and Exits). A single origin, like the entrance to a station, may have many possible destinations for the pedestrians using it (several station exits or platforms) just as one exit or destination may be ‘targeted’ by several origins.

These demand patterns are typically presented in the form of an Origin-Destination matrix (OD matrix), which is a table mapping either the absolute number of pedestrians moving between each of the respective origin and destination pairs, or the percentages thereof.

Demand is also expressed in terms of pedestrians entering a site over time and this is typically reflected in the form of an Arrival Profile. The Arrival Profile defines the arrival of pedestrians distributed along a ‘timeline’.

To define the demand within a LEGION model, object pairs from the OD matrix are combined with Arrival Profiles (each Entrance in the model must have at least one Arrival Profile associated with it).

As you will see in Data profiles worksheet , LEGION Model Builder comes with a spreadsheet template that can generate Arrival Profiles from an OD matrix.