Intermodal journey planner

An Intermodal Journey Planner (IJP), or Trip Planner is computer system which can provide a traveller with an itinerary for an intermodal passenger transport journey. The system can provide timetable, routing and other travel information. A single journey may use a sequence of several modes of transport, meaning that the system must know about public transport services (bus, train, aeroplane, tram, metro) and about transportation networks (roads, footpaths, cycle routes) for private transportation (automobile, walking, bicycle).

Basic features

Fundamental to an IJP is a journey planner engine with public transport timetable and road routing information and knowledge of the stops and interchanges: it may also be able to supply maps. An IJP will also have one or more user interfaces optimised for different purposes, for example, for online self-service use with a Web browser, for call centre agents, for use on mobile devices, or special interfaces for visually impaired users. An IJP will provide specific journey plans made up of one or more journey legs. It may also support other representations such as full timetables, stop departures boards, etc.

Fully featured IJPs are capable of incorporating real-time information along with the planned timetable, for example to provide live departures from a particular stop, to include incident information about situations that may affect a journey, or to compute journeys that take into account predicted delays, allowing the user to perform journey repair to recover from a disruption to normal services. IJPs may also cover road-real time data and may be considered part of an Intelligent Transportation Systems.

An intermodal journey planner (IJP) calculates the best overall journeys between origin and destination for the user's preferred modes.

Public transport routing

For public transport routing, the engine will consider journeys that combine different public transport modes, constrained by times of arrival or departure. It may support different optimisations - for example, fastest, least changes, with constraints to go via or to avoid specific way points.

Most engines are not capable of multimodal fare optimisations (e.g. cheapest, or most flexible) but may be able to advise fares for a single mode.

Car routing

The planning of road legs is usually done by a separate subsystem within an IJP, but may consider both single mode trip calculations (e.g. with private traffic and/or public transport) as well as intermodal scenarios (e.g. Park and Ride, kiss and ride, etc.). Typical optimisations for car routing are shortest route, fastest route, cheapest route and with constraints for specific waypoints.

Some advanced IJPs can take into account average journey times on road sections, or even real-time predicted average journey times on road sections.

Pedestrian routing

An IJP will be able to provide detailed path routing for pedestrian access to stops, stations, points of interest etc. This will include options to take into account accessibility requirements for different types of user, for example; 'no steps', 'wheelchair access', 'no lifts', etc.

Bicycle routing

Some IJP systems can calculate bicycle routes, integrating the off-road path network as well as the road network. Advanced systems allow the user to specify preferences for quiet or safe roads and may also support contour optimisation to minimise the effort needed to overcome vertical differences.

User interfaces

An IJP will typically comprise one or more back-ends (exposed as web services which may be used by different front-end applications which manage interaction with the user). Interaction will be optimised for different types of user and device, for example:

Interactive channels

Printed output

IJP may also provide multiple printed output, for example:

Public transport data

An IJP integrates a number of different types of data about the planned services for the Public Transport system, including:

In order to develop data sets that can be integrated economically and robustly, data standards and conceptual models, such as Transmodel are used.

Private transport data

An IJP also integrates a number of different types of data about the transport networks available for use by private vehicle and pedestrian access,

Real-time data

Advanced IJP engines are capable of integrating Real-time Information into their computations. This may be of two main types

Real-time prediction information

Automatic Vehicle Location (AVL) Systems know the actual position of their vehicles compared to the timetable and can pass on the real-time and forecast information to the IJP system. The IJP engine incorporates this up-to-date information into its database and considers it in all requests. Based on this information IJP is able to indicate the punctuality or delays for each mode of transport in a departure monitor. An IJP will use a real time interface such as Service Interface for Real Time Information to obtain this data.

Real time Road Information may come from systems such as UTMC

Situation information

A Situation is a software representation of an Incident (for example security alert, cancellation or bad weather) or Event that is affecting or is likely to affect the transport network. An IJP can integrate Situation information and use it both to revise its journey planning computations and to annotate its responses so as to inform users through both text and map representations. An IJP will typically use a standard interface such as SIRI, TPEG or DATEX2 to obtain Situation information.

Incidents are captured through an Incident Capturing System (ICS) by different operators and stakeholders, for example in Transport Operator Control Rooms, by broadcasters or by the emergency services. Text and image information can be combined with the trip result. Recent incidents can be considered within the routing as well as visualized in an interactive map.

See also

Examples of IJP systems

Large scale Examples of IJP systems include

Some of these systems are based on open source applications

References