www.ptvag.com Macroscopic and Microscopic Simulation for the Evaluation of People Mover Systems Dr. Peter Mott, Sven Beller PTV AG 2010
Contents Why Transport Planning & Simulation? The Macroscopic View (VISUM) Microscopic Simulation (VISSIM) Summary and Outlook PTV AG 2010 2
Why Transport Planning & Simulation? Sophisticated transport systems require sophisticated tools for their evaluation. Several subsystems and many parameters form a complex system: > System operation (incl. empty vehicle management) > Temporal and spatial variation of passenger demand > Passenger interaction > Interdependencies between transport modes (e.g. at transfer stations) > Vehicle attributes (incl. capacity, safety systems) > Simulation is a powerful tool to comprise all this into a single, realistic model for technical and economical assessment. PTV AG 2010 3
Example 1: Metro connects with People Mover PTV AG 2010 4
Example 1: Metro connects with People Mover Frequency: 10 mins Capacity: 4 x 80 = 320 pax Frequency: 5 mins Capacity: 2 x 20 = 40 pax PTV AG 2010 5
Example 1: Macroscopic view (VISUM) Static assignment of passenger flows (no temporal variation) Apparently no capacity problems PTV AG 2010 6
Example 1: Macroscopic view (VISUM) Time dynamic approach: Passenger flows vary in time Capacity problems in peak period! PTV AG 2010 7
Microscopic simulation (VISSIM) > Public and private traffic > Scientifically approved models for car following, lane change and pedestrian movements. > From one intersection to medium-sized cities > Priority rules and signal control This video file can be downloaded at www.ptvag.com/vissim_avi PTV AG 2010 8
Microscopic simulation (VISSIM) How to implement a PRT system? > Modelled directly in VISSIM: > Network infrastructure > Passengers > Vehicles and vehicle interaction > Modelled by scripting through VISSIM s API (application programming interface): > Passenger flow control > Vehicle allocation and routing > Empty vehicle management APIs expand VISSIM s capabilities beyond what comes out of the box PTV AG 2010 9
Example 2: Demand-responsive PRT system Idea > Idle vehicles are allocated in a depot or at stops > Passengers trigger trip request at a station to their destination > Free vehicle is assigned to trip, switches are set to direct the vehicle automatically to destination along the shortest path 4.7 km Guideways 17 Branches 7 Stations 1 Depot PTV AG 2010 10
Example 2: Demand-responsive PRT system Simulation principle (in brief): 1. Passengers demand trip at a station 2. Idle vehicle is assigned for that trip (inside/outside station) 3. Vehicle travels to destination on shortest route, interacting with other vehicles 4. At destination, passengers exit at alighting position 5. Empty vehicles either > stay at station > are relocated to another station > return to depot Special thanks to ULTra PRT Ltd. for providing the 3D model of the pod vehicle PTV AG 2010 11
Example 2: Demand-responsive PRT system Performance indicators recorded (extract): > System response time (passenger waiting time) > Total trip time > Vehicle kilometres (occupied/unoccupied) Testing different scenarios by varying e.g. > Passenger demand > Total no. of PRT vehicles > Station layout > Empty vehicle management PTV AG 2010 12
3D-View of the Simulation of a Demand-responsive PRT System This video file can be downloaded at www.ptvag.com/vissim_avi PTV AG 2010 13
Summary & Outlook The impact of People Mover and PRT systems can be assessed by PTV Vision software tools. > The macroscopic approach (VISUM) provides time-dynamic methods for large, multi-modal networks. > The microscopic simulation (VISSIM) allows for detailed modelling and analysis of the system operation down to each passenger and vehicle. > Interfaces support the application of both tools. The application of such tools > contributes to an efficient, straight-forward planning process > provides a solid base for financial and economic decisions PTV AG 2010 14
www.ptvag.com PTV. Planning Transportation Visions. PTV AG 2010 15