integration of transportation system analyses in cube wade l. white, aicp citilabs inc
TRANSCRIPT
Integration of Transportation SystemAnalyses in Cube
Wade L. White, AICP Citilabs Inc
A comprehensive transportation planning system Cube has two parts:
Cube Base: the user interface comprised of 3 sections:
– Application Manager : flow-chart style tool for building model systems
– Scenario Manager: tool for applying the model to multiple scenarios
– Graphics: editing of all data in text, tabular and graphical form
‘Functional Libraries:– VOYAGER– TP+– TRANPLAN– TRIPS– CARGO– AVENUE– DYNASIM– Analyst– LAND (in development)– LOGIT (in development)
Cube Avenue
Transportation modeling tools
Macroscopic Modeling
Mesoscopic Modeling
Microscopic Modeling
Macroscopic Modeling
Macroscopic Models generally consider the entire system and estimate routing and flows through a network for a time period.
Currently used for almost all strategic (long-range) planning. FSUTMS Models Very fast analysis of very large areas. Models the behavior of people taking into account:
– Why people are making trips– Why they select a particular mode– Why they select a particular route
Cube Voyager
the latest technology for the forecasting of personal travel. a modular and script-based structure allowing the incorporation of
any model methodology HCM junction-based capacity restraint for highway analysis includes highly flexible network and matrix calculators for the
calculation of travel demand and for the detailed comparison of scenarios.
designed to provide an open and user-friendly framework for modeling at any level
This makes the management of data a snap, and the coding of complex methodologies simple via a step-by-step approach.
Cube Voyager Model
Highway Traffic Flow
Mesoscopic Models
MESOscopic are MORE detailed than MACROscopic travel demand models but are LESS detailed than MICROscopic simulation models.
Cube Avenue, a mesoscopic dynamic assignment model is available for CUBE.
With mesoscopic models, it is still possible to quickly analyze larger areas with a more detailed model which overcomes the pitfalls of the macroscopic travel demand models.
– Takes into account intersection configurations and controls– More detailed estimates of delay, travel time, and capacities– Enforces capacity limitations and the effects of queues ‘blocking back’– Models flow curves and changing demand throughout an analysis period– Allows vehicles to respond to traffic conditions and change their route
Cube Avenue representing vehicles as discrete packets or individual vehicles
assigning a specific time of departure from the origin point in the network to each packet or vehicle
routing the vehicles along multiple paths in response to dynamic traffic conditions
representing queues and bottlenecks including ‘blocking back’ or the formation of queues on a roadway segment or at an intersection which spill back up-stream to block roadway segments which feed into the roadway segments
Region-wide, corridor-level
Evacuation modeling, greater analysis of geometrics, traffic control and ITS strategies
Quantify impacts of upstream traffic congestion
Summary of Avenue:– Measure queuing at intersections and merge points in a network
– Isolate secondary impacts from one intersection through another
– Evaluate the benefits of ITS (intelligent transportation system) projects
– Simulate alternative infrastructure, operational, and policy changes to optimize emergency evacuation plans and strategies
– Test strategies to improve arrival and departure from stadiums and other special-event facilities
NERPM Dynamic Traffic Assignment
Build TOD Vehicle Trips
Establish Dynamic Assignment Parameters
Dynamic Traffic Assignment
NERPM DTA Animation
Microscopic Modeling
Microscopic models are VERY detailed and take into account vehicle’s interactions with the following aspects:
– The roadway geometry (lanes, turning lanes, weaving areas, exclusive lanes)– Physical size of different types of vehicles– Details of traffic control (signal timing, phasing, geometric configurations)
Microsimulations are Stochastic (contain random processes) which emulates:
– The fluctuating nature of traffic flows– Variations in human behavior and responses
Microsimulations are Multimodal and can consider the effects of traffic interacting with all other users of the transportation system:
– Pedestrians, Bicyclists, Motorcyclists– Trucks and other Heavy Vehicles– Transit vehicles, Taxis, Light and Heavy rail vehicles
Cube Dynasim
Integration with demand models– Polygon select of an area and export of data to the microsimulation. Saves enormous
time Stand alone microsimulation
– Layered approach much more intelligent than other software 2d and 3d animation
– Export of shape layers and images– Use of industry standard 3ds files for high quality 3d– True sharing of results via exportable animations
Scenario-based Simulation– Only one Dynasim project for all simulation alternatives– Eliminates redundancy– Ensures consistency
Analysis of Multiple Runs inherent to the system– Automatically performs multiple runs and summarizes results– Ensures a robust analysis with no additional burden on the user
Interactive Results– Completed simulations may be exported to a DynaViews program– Interactive Animations with the same features as Dynasim– Freely distributable
Building a Dynasim Simulation
Dynasim Simulation
Roundabout Simulation Bus Terminal Simulation
Summary Modern software platform providing:
– integrated environment for regional planning
– regional traffic simulation
– corridor level detailed project evaluation
Cube Voyager for regional planning – traffic flows
Cube Dynasim for corridor simulation = animations
Cube Avenue (DTA) for region-wide simulation – queues/ delays
Questions