RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
RULE-BASED OBJECT-ORIENTED MODELLING OF
PUBLIC TRANSPORT SYSTEMS
Otto Anker Nielsen ([email protected])
Research Professor, Ph.D.
Centre for Traffic and Transport
Technical University of Denmark
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
The Presentation• The project• Background• Object oriented approaches• The data model• Elements of the Transport Object Platform• Examples• Utilising TOP in transit assignment
procedures• Advantages / summary
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
The project
• Internally funded development project
• Developed in cooperation between WS Atkins, the Technical University of Denmark and ESRI
• Aim: Making it possible to handle complex, multi-modal transportation data in a GIS
• On top of that: Advanced analysis and modelling tools
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Background
TOP
Market Opportunity
Research (BRIDGES)
Technology Available(ArcGIS)
Practical Experience
(CRM)
Research (SPOTLIGHT)
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Typical problems in prior GIS
a) Network represen-tatiton by pseudo links and nodes whicheach are digitised
Line a,b Line a
Line b, c
Line c
Network withbusroutes:
Line a Line aLine a Line a
Line b
Line b
Line b
Line b
Line c
Line c
Line cLine c
Line aLine a Line a
Line b
Line b
Line b
Line c
Line c
Line cLine c
b) Network represen-tation with turn tables:
Line a
Line bTurn table for each node with transfers between
lines who each have been digitised
Line a,b Line a
Line b, c
Line c
c) Network representationby dynamic segmentation and transfer table
Each route is described by dynamic segmentation
(data-base tables maintained by the GIS)
Transfers are described by database tables (not
maintained automatically by the GIS)
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
• A detailed traffic model covering half of Denmark
• Timetables (all runs with about 2,500 lines ~ 0.4 mio. stops, 30,000 stop groups and 4 mio. pseudo arcs)
Background – East Denmark Model (CRM)
The CopenhagenRegion
Funen
Germany
Other areas
Zealand
Sweden
N
EWS
0 20
Jutland
FixedLink
Ferry orboat
40 60 km.
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
• Complex dataflow, Difficult to maintain consistency• Separate models used proprietary data formats
Background - CRM
Timetables fromRail and bus co.
Punctuality data
Results
Plan ofoperation
Timetableinterpreter
Frequency-basedtime-tables
Geographic datamodel
Data integrationmodule
Timetablegenerator
Main data model
Bus stops andstations
Road-, metro-and rail links
Zonal map
Supply- andassignment models
Demand models
Reference data
Relational Database Geographical Information System
Data generating module
Traffic forecasting system
Other data
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Background - Technology
Newest generation of GIS is:
• Object Oriented
• Flexible - new and customisable data models, etc.
• Extensible & Programmable - embedded functionality
• Open - Standard DBMS, COM, VBA etc.
• Offers advanced features - tools, versioned editing etc.
It is now possible to create new topological objects,
design new data models and embed functionality!
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Object oriented approaches (1)
Objects encapsulates:
– Properties
– Functionalities
– Events
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Object oriented approaches (2)
Objects can:
– Inherit properties and functionalities– Be grouped together (within or between
classes)– Be related to each other (within or between
classes)– In ArcInfo they can also follow connectivity
rules to each other
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
The Transport Object Platform consists of
• Conceptual model
• Data model
• Programmed functionality in data objects
• Editing and Visualization tools
• Advanced modelling and analysis tools
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Data model (1)
L1
L2
Network NetworkLR between features in networks
1 Feature = Sequence of features
+
Infrastructure NetworkRoads, Rail, Tram, Bike,Walk, Intersections, etc.
Basic Public NetworkStops, Terminals, Transfers,Route-building blocks (Route Segments)
Detailed Public Network
Features + Tabular data
Route as sequence of Route Segments
Detailed time-table data in tabular form
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Data model (2)TOP Conceptual Overview
RouteSegment
RouteGroup
TimePattern
Route
ROUTES
FrequencyRun
TransportJunction
TransportEdge
Turn
PHYSICALNETWORK
Terminator
Zone
Matrix
Connector
DEMAND
Terminal
Stop
StopGroup Transfer
TERMINALS
DiscreteRun
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Data model (3)TOP Conceptual Overview
Terminator
Matrix
Connector
TransportJunction
TransportEdge
Turn
RouteSegment
Terminal
Stop
StopGroupTransfer
RouteGroup
Route
DEMANDTERMINALSROUTESPHYSICAL NETWORK
FrequencyRun
TimeTable
CatchmentArea
To
From
From/to To
To
From/to
From/to
To
At
From/to
From/toSequence of
Sequence of
For Belong to
From/to
Fulfil
Belong to
Belong to
From/to
From/to
DescreteRun
Fulfil
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Data model (4)
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Data model (5)
TimePatternDiscreteRun
FrequencyRun
«RelationshipClass»RouteDetail
Route
«RelationshipClass»TimePatternDetail
Turn
StopRouteSegment StopJunction
TransportEdgeMatrixMatrixElement
Terminator
«RelationshipClass»RouteSegmentDetail
StopEdge
ESRI Classes::Object
Run
ESRI Classes::Feature ESRI Classes::SimpleEdgeFeature
ESRI Classes::SimpleJunctionFeature
ChangeEdgeConnector
TransportJunction
DEMAND
ROUTENETWORK
PHYSICALNETWORK
Terminals
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Stops
TransportEdge
TransportJunction
Stop
StopJunction
StopEdge (default)Linear Reference
Off
set
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
A Road Network
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Stops are added,they automatically connect to the roads
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Draw bus routes by clicking nearStopJunctions, where the bus stops and near roads to guide
the bus
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
The Route automatically swapsto the road network, builds
relationships to the roads and creates Timepatterns
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
A road is modified…
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
…and the Route changes.Drivingtime in the TimePatterns is likewise
changed
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Grab a Stop and move it…
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
The Stop triggers move of the StopJunction, which in turn shortens the Route and changes
TimePatterns.
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Modifying a road with Stops…
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
…will modify the Route and TimePatterns and move the StopJunctions, but leave
the Stops
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Moving a road and rubberbanding..
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
…also changes Routes andStopJunctions and TimePatterns
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
In addition complex schedulingdata like these…
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
..can be presented in 3D.
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Utilising TOP in Public transport assignment models
Different conceptual levels of networks:
• Geographic network
• Organisational network
• Calculation network (logical network, not only a graph)
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Multi-modal modelling – extracting the logical network from TOP
Terminator
Transport-Junction
Stop
Stop.Route.Arrival.Run
Stop.Route.Departure.Run
Connector(to Stop)
TransportEdge.Forward
TransportEdge.Backward
AccessEdge.ToStop
AccessEdgeFromTransportJunction
AccessEdge.FromStop
TransportEdge
Stop.Route.Continue.Run
Stop.Route.Enter.Run
Stop.Route.Exit.Run
Route.FromStop.Run
Route.ToStop.Run
STOP
StopGroup
TransportJunction
Connector (to TransportJunction)
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Rule based assignment models
• The graph is built dynamically (graph pruning)
• Search algorithms utilise the hierarchical structure of the network
• Á priori knowledge and geographical information can be used in label correction methods
• Refer to paper at TRISTAN IV
RULE-BASED OBJECT-ORIENTED MODELLING OF PUBLIC TRANSPORT SYSTEMS
Centre for Traffic and Transport (CTT), Technical University of Denmark (DTU)
Advantages and summary
• GIS Environment is easy to use & intuitive• Open, Extensible & Programmable• Handles multiple layers of data, maintains
consistency• By using consistent and detailed data, better
and faster models can be implemented • Cut data-handling efforts significantly• Facilitate work with more detailed data