How Many Engineers Does It Take to Count a Roundabout? UNIVERSITY OF MISSOURI-COLUMBIA

1. How Many Engineers Does It Take to Count a Roundabout?UNIVERSITY OF MISSOURI-COLUMBIA Carlos Sun, Ph.D., P.E.

2. Counting Traffic is Easy, Right?

3. A Discussion of Automated Roundabout Counting: Introduction Conservation equations Hardware Software/Algorithm

4. Quick Bio • The road to traffic nerdom • Start as electrical engineer in 1990 • hardware/software • Studied transportation engineering at UCI • ITS research at California PATH • 11 years teaching transportation, 8 at Mizzou

5. Roundabouts in the U.S. • Roundabout is one tool in a panoply of solutions for intersections • Modern roundabout: Las Vegas, 1990 • Increasing use, ~2000 as of January 2009 (RoundaboutsUSA) • 20k in France, 15k in Australia, 10k in the UK • More and more roundabouts need to be counted and studied-> job security, yeah!

6. Magic Roundabout: Magic Roundabout, Swindon, UK6 approaches/departures, 1 big and 5 kiddie roundabouts

7. Conservation Equations

8. Conservation Equations (FHWA): 4 Legged Roundabout • 4x4=16 movements • 2x4=8 count locations • Underspecified problem

9. Conservation Equations: 4 Legged Roundabout • But wait, if we neglect u-turns: • 12 movements • 12 counts: 8 entry/exit counts + 4 circulating • Problem solved?

10. Gauss and Jordan say: Denied • Not linearly independent • It’s still underspecified • We need to count specifically: • right turns, or left turns, or through movements • but at entry point, not know which way a vehicle will end up!

11. Hardware

12. Video Field of View • Apart from using cellular, bluetooth, or other AVI-type tracking • What are some achievable fields-of-view?

13. Halls Ferry, STL

14. Creasy Spring, Columbia

15. Bearfield, Columbia

16. Waldenmaier (NCHRP 572)

17. Camera Mounting Tripods, e.g. miovision Pole mount, e.g. Russell Trailer, e.g. MU

18. Mirror Remote Reality Elliptical Dome, MU NCHRP 572

19. Software/Algorithms

20. Count Estimation Systems, e.g. Eisenman and List • Additional spec. w/Time stamps • Count entrance, exits, circulating • Assume FIFO • Estimate turning movements

21. Other Estimation Procedures • Bi-Proportional: log-linear model (Van Zuylen & Willumsen, Bell, Nihan & Davis, Hellinga) • Algebraic Solution: rights turns (Robinson, Rodegerts et al.) • Sequential Quadratic: constrained least squares (Cremer & Keller, Ashok, Dixon & Rilett) • Factored Survey: surveys (Dixon)

22. Time Series Method

23. Virtual Loop Time Series, MU

24. Following Different Movements • Differentiating b/t: • Circulating • Entering • Exiting • Augment measured variables • Not longer underspecified • Problem w/tailgating

25. Tracking Systems

26. Tracking Type Systems, e.g. miovision

27. Common Tracking Algorithms (Coifman & Malik) • Model-based – detailed geometric object models • Region-based – connected region, “blob” • Contour-based – reduce to boundary • Feature-based – distinguishable pts., corners • Group rigid features moving together

28. Algorithm Step Examples • Vehicle image capture • Background subtraction • Gradient/edge detection • Feature vectors • Inter vs. intra cluster movement

29. Feature-Based Tracking

30. Multi-Detector Control

31. Multiple Cameras, e.g. Autoscope • Junction control • 8 cameras • 31 counting stations • 5000 vph • Krakow, Poland • No turning movements necessarily

32. So how many engineers does it take to count a roundabout? Assign a person to count each approach? (e.g. 4 persons for a 4-legged RA) Have an engineer design an automated system (e.g. HAL 9000)

33. Questions/Comments? FOR MORE INFORMATION PLEASE CONTACT: CARLOS SUN UNIVERSITY OF MISSOURI csun@missouri.edu Feasibility of an Automated Solution for Deriving Roundabout Turning Movements; Rescot, Sun; TRB 2008 Paper #08-0388 Automated Capturing of Roundabout Turning Movement Counts; 2008 National Roundabout Conference http://www.teachamerica.com/RAB08/ListMenu.html