The Technology Side of the Sydney Coordinated Adaptive Traffic System (SCATS)

1. The Technology Side of the Sydney Coordinated Adaptive Traffic System (SCATS) Presented by: Betsy Williams TransCore

2. SCATS Background • The Roads and Traffic Authority of New South Wales (RTA) • Developer and primary user of SCATS • Continued innovation through user group involvement • Extensive user base • Effective, mature, practical system • Worldwide - over 21,000 intersections under SCATS control in 71 installations

3. SCATS Worldwide System Installations Dublin Waterford Rzeszow Gresham Park City Menlo Park Sunnyvale Detroit Shenyang Tehran Mashhad Delaware Durham Cobb Co Shijuazhuang Israel Yanbu Chula Vista Yichang Tianjin Shanghai, Ningbo Suzhou Hangzhou Pasco Co. Guangzhou Doha Mexico City Toluca Hong Kong Manila Cebu Dacca Hanoi Pattaya Vietianne Kuala Lumpur Seremban Singapore Brunei Sandakan Jakarta Bandung Suva Fiji Darwin Perth Adelaide Sydney Melbourne & many other cities Pietermaritzburg Concepcion Auckland Wellington Christchurch + 11 cities

4. SCATS US Installations

5. Benefits of SCATS • Reduces need/effort for updating signal timing • Accommodates traffic fluctuations • Allow special functions to be installed for event centers • Assist maintenance of signals via monitoring features • Collect volume counts for planning purposes

6. Typical Adaptive vs. TOD Graph

7. SCATS Objectives Select cycle length, splits and offsets to achieve • Minimum stops with light demand • Minimum delay with normal demand • Maximum throughput with heavy demand

8. SCATS Detection

9. SCATS Detection Requirements NO • Advanced • Upstream • Downstream • Mid-block YES • Stop bar

10. SCATS Detector Requirements • Presence detection • Optimal strategic SCATS detectors are 6 ft x 15 ft located at the stop line for all lanes • Detectors can be longer or shorter if needed, however shorter is better than longer • Local actuation detectors may be used at minor intersections and can be varying in size

11. Typical Detector Layout

12. SCATS Detectors • SCATS operates by looking at “space” between vehicles • Eliminates vehicle length from equation • Graph is linear with no double curves Loop Space Time (secs)

13. SCATS Equipment

14. SCATS Controllers • SCATS uses 2070 controllers • 2070 Lite – no VME backplane • Eagle and Econolite 2070s • 2070N – reuse of existing cabinets • Eagle M-50 series • 170 E controllers • SafeTran or McCain controllers

15. Hardware Requirements • Server Requirements • Minimum 400 MHz Intel processor – 128M RAM • Windows NT or 2000 • Laptop and Workstation Requirements • Minimum 400 MHz Intel processor – 128M RAM • Windows NT, XP or 2000 • Dial-in access • 56K modem • VPN access

16. Communications • Leased line, twisted pair copper, fiber optic, spread spectrum radio • 300 bps per controller • Point-to-point communication • Point-to-multipoint communication • Ethernet/IP communications

17. SCATS Operation

18. SCATS Modes • Adaptive Mode • Traffic adaptive coordination mode • Time-of-Day Mode • Fixed-time coordination fallback mode • Free Mode • Vehicle actuated operation • Master Free Mode • Vehicle actuated with SCATS calculated splits • Flash

19. SCATS GUI • Familiar Windows interface • Pull down menus • Real-time information

20. Active Time-Space Monitor

21. Reports

23. For additional information contact:Betsy Williams TransCore(770) 293-1920betsy.williams@transcore.comorTravis White TransCore(801) 293-1920travis.white@transcore.com

25. Proven Performance • Chula Vista, CA • Travel Time Reduced By Up To 15% • Travel Speed Increased By Up To 18% • Delay Reduced By Up To 43% • Menlo Park, CA • Stops Reduced By Up To 24% • Travel Time Reduced By Up To 28% • Delay Reduced By Up To 44%

26. Proven Performance • Road Commission For Oakland County, Michigan • Corridor Travel-Time Reduction Range 6.56% To 31.8% • Average Travel-Time Improvement 7.8% For Peak Traffic During Peak Periods • Broward County, Florida • Stops Reduced By Up To 28% • Travel Time Reduced By Up To 20% • Delay Reduced By Up To 42%

27. SCATS Functions - CYCLE LENGTH • Automatically calculated to try to maintain Degree of Saturation between 80% and 90% on the lane with the highest DS • Lower and upper limits are user definable (20 secs to 190 secs) • Can vary by up to 21 seconds per cycle – usually only 2 to 5 seconds

28. SCATS Functions - SPLITS • Varied automatically by up to 4% each cycle. • Tries to maintain equal Degree of Saturation on competing approaches. • Minimums are user definable. • Maximums are limited by cycle length and minimum requirements of other phases.

29. SS 2 SS 3 SS 1 SYSTEM SCATS Functions - Linking • Intersections can "marry" or "divorce " with each other • Married intersections operate on a common cycle length (and offset plan) • Intersections marry: • when their CL's are within 10 sec or • when one-way volume exceeds a configured threshold or • when a “forced” / continuous “marriage” is required

30. SCATS Functions – OFFSETS • The best offsets are selected for the high flow movements. • Preset offset plans automatically vary to compensate for varying cycle lengths. • Directional bias based on measured flows.

31. Intersection Display Currently activated detectors shown blue. Shown red if faulty

32. Alarm Display All operator actions and alarms can be sorted, filtered and printed