Transport systems

The transport supply consists of several transport systems. Links, turns and connections can be attributed subject to the transport system ("transport system-based"). In particular, it is possible to specify whether a transport system is allowed to traverse one of these network objects or not. For example, links can only be opened for the transport system Car, but not for the transport system HGV. Furthermore, the impedance functions (Impedance and VD functions) are defined for the assignment transport system dependent.

A transport system has the following properties:

  • Transport system type (available are PrT, PuT, PuTWalk. PuT-Aux or Sharing)
  • Means of transport (= vehicle type), for example car, tram, taxi, wheelchair

Note: The number of modeled transport systems, modes or demand segments is not limited.

The types of transport systems are distinguished as follows:

  • PrT

Travel times of a private transport system depend on the following attributes:

  • Maximum speed of the means of transport for example 100 km/h for HGV
  • Permitted speed of the traversed link for example 80 km/h
  • Capacity of the traversed link
  • PuT

Run times of vehicles of a public transport system and the dwell times at stops are determined by the timetable.

  • PuTWalk

This mode serves to model entrance and exit paths for public transport and walking transfer links between stop points of a stop or several stops. In order to calculate a public transport assignment, at least one transport system of type PuTWalk must exist. Several transport systems of type PuTWalk can be defined.

  • PuTAux

This type describes subordinated PuT transport systems without a specified timetable. It is suitable for the following use cases.

  • Modeling lower-ranking public transport supply:

In large networks, for example in train networks, one often does not want to enter the reachability of long-distance stations by means of a connector, but in instead one wants to roughly display the available public transport supply. For a simple representation such as this, it makes sense to define one or several PuT Aux transport systems. In this case, the successive public transport supply is only described as a link network with run times. Line routes and timetables are not used.

  • Modeling different types of public transport connectors:

A zone is connected to the PuT supply via one or several PuT systems. In many cases, passengers not only select nearby start stops for their PuT journey that can be reached on foot, but they also select distant stops that can be reached by bicycle or car (Park&Ride, Kiss&Ride, Bike&Ride). In order to be better able to model these alternatives, for connectors it is possible to disable individual transport systems of type PuTWalk or to define different connector times. Two modes can then be defined for the PuT assignment: one mode that is only used if the stop is reached on foot and one mode that can be used if the stop is reached by car or bicycle.

  • Sharing

A public transport system of the type Sharing is required to account for sharing models in timetable-based assignment.

The Table 4 provides an overview of properties of the transport system types:

Table 4: PrT transport systems properties

 

TSys type

Comment

Example

PrT
  • Transport system for private transport
  • Capacity-dependent travel times resulting from link speed and turn times

Car,

HGV, Bicycle

PuT
  • PuT with timetable
  • Run times from timetable
  • Transport system is not valid for transfer walks or on a connector

Bus,

Tram,

Train

PuTAux
  • Public transport system without timetable or PrT access system to PuT
  • Run times result from links
  • Transport system is not valid for transfer paths within a stop - just between stops

Bus,

Taxi,

P&R access

PuTWalk
  • Transport system for
  • access/egress paths from/to stops or
  • transfer paths within a stop or between stops
  • Travel times from links or from a transfer walk time matrix of the stop

Footpath,

Escalator,

Lift

Sharing

Car sharing

Bike sharing