1. Micro-Simulation of Automated Vehicles with Minimal Central Control Advanced Transit Association Annual Technical Meeting January 12, 2008 Washington, DC Robert Johnson R. E. Johnson Consulting Rockville, Maryland www.REJConsult.com

2. 2 Different Types of Automated Transit Vehicles Track based –Run on special track that provides lateral guidance and power (most People Movers are in this category) Automated Road Vehicles –Steer themselves along a flat surface without mechanical guidance –Have a self-contained power supply –Max speed 20 - 25 mph (32 - 40 kph) on exclusive roadway

3. www.REJConsult.com3 Examples of Small Automated Road Vehicles CyberCab: proposed by 2getthere which operated the first public ARV ULTra: scheduled to begin service in 2009 at Heathrow airport, London

4. www.REJConsult.com4 Presentation: Three Related Topics Micro-simulation model for Automated Road Vehicles Using the model to demonstrate a simple vehicle- based control strategy Simulation of a shuttle application

5. www.REJConsult.com5 Simulation represents guideway as straight segments alternating with circular arcs

6. www.REJConsult.com6 Library of Special Guideway Elements (in Various Stages of Development) End-of-line station Center platform station “T” Intersection

7. www.REJConsult.com7 Vehicle-based Control System: How to Handle Conflicts Vehicles know the complete layout of the system, and know exactly where they are At each merge or crossing point, one lane always has priority If a vehicle is in the low priority lane, it uses its sensors to scan the high priority lane, and yields if a vehicle is detected

8. www.REJConsult.com8 Vehicle in Low Priority Lane Yields

9. www.REJConsult.com9 Vehicle-based Control System (cont.) Vehicles use sensors to watch for objects in their path (another vehicle or foreign object) If unexpected object detected, vehicle stops and notifies human operator at central control Central control computer: –Assigns destinations to vehicles –Holds vehicles at stations to smooth system flows –No safety-related functions

10. www.REJConsult.com10 Example Application - Shuttle Two-way guideway with a station at each end Six-passenger, shared vehicles 5 second minimum headway Maximum passengers per hour per direction –4320 theoretical (6*3600/5) –Practical maximum is probably between 1000 and 2000 Better than conventional people mover shuttle since can give riders very short wait times (say, 60 sec max)

11. www.REJConsult.com11 (Very Short) Shuttle Using Automated Road Vehicles

12. www.REJConsult.com12 End-of-Line Station Outbound paths

13. www.REJConsult.com13 End-of-Line Station Inbound paths - Vehicles back into berths

14. www.REJConsult.com14 Path-Crossing Conflict Vehicle Leaving Berth Yields

15. www.REJConsult.com15 Merge Conflict Vehicle From Berth Nearer Exit Yields

16. www.REJConsult.com16 Merge Conflict Leaving Station Click image at left to play video if.WMV file was downloaded OR Press button below to play video from web

17. www.REJConsult.com17 Vehicles Crossing Paths Click image at left to play video if.WMV file was downloaded OR Press button below to play video from web

18. www.REJConsult.com18 Simulation of Complete Shuttle Click image at left to play video if.WMV file was downloaded OR Press button below to play video from web

19. www.REJConsult.com19 Conclusions and Future Work Vehicle-based control seems feasible, at least in simple systems Shuttle systems could be implemented at very low cost, after development of electronics for vehicle Next step: develop detailed operating rules for vehicles in T intersections and center platform stations