Modeling vehicle compositions

You define vehicle compositions for vehicle flows that consist of one or multiple vehicle types. If you are not using dynamic assignment, you must define vehicle compositions based on vehicle types to have vehicles generated for vehicle inputs. As a rule, there will be several vehicle compositions, consisting of different shares of vehicle types, for example Only cars, Cars with a 5% share of trucks. There are also vehicle compositions that include pedestrians on links (Modeling links as pedestrian areas). For the latter, you define relative volumes for the vehicle types Man or Woman. You define pedestrian compositions for pedestrian flows used on surfaces. Do not define vehicle compositions for pedestrian flows on surfaces, as these would be bound to links and the model of the flow of traffic according to Wiedemann (Operating principles of the car following model).

For vehicles, which only drive in PT routes, no vehicle compositions are necessary, for example, for public transportation by trams and city buses (Modeling short-range public transportation).

The number of vehicles used at a pedestrian input is defined by the Volume attribute and influenced by the Volume type attribute (Attributes of vehicle inputs). You can allocate one or several vehicle compositions to a vehicle input (Attributes of vehicle inputs). If for a link, you allocate a vehicle composition with one vehicle type each to several vehicle inputs and select Volume type > Exact, you can define the exact number of vehicles used on this link.

You allocate a relative volume and desired speed distribution to each vehicle type (Using desired speed distributions).