1. AN INTRODUCTION TO

2. Outline
 Example of systems & definition
 How did Sain get involved?
 Scan Tour & ALDOT’s reaction
 How it works
 Different systems
 Graphs
 Status of ALDOT Projects
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3. Example of Systems
 InSync
 SCATS
 SCOOT
 ACS Lite
 Several others…
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4. Definition
 Traffic signal timing control technology
that has the ability to utilize real-time
traffic information to adjust traffic signal
system timings in an effort to reduce
congestion and delay.
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5. How did we get involved?
 FHWA Every Day Counts (EDC)
 EDC is designed to identify and deploy
innovation aimed at shortening project delivery,
enhancing the safety of our roadways, and
protecting the environment.
 Adaptive Signal Control Subcommittee
 Members consist of ALDOT, FHWA, City of
Montgomery, and Sain Associates
 Sain is the only consultant on the committee!
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6. Committee Members
 FHWA
 Jeff Dogan
 ALDOT
 Stacey Glass, Gary Moore, Kim Norton,
Robert Blankenship
 City of Montgomery
 Bubba Bowden, Tim Foster
 Sain Associates
 Jeff Stephenson
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7. Scan Tour: Sep. 12-14
2011
 Visited 3 locations in GA
 (1) City of Alpharetta
3 1
○ Tested InSync, SCOOT 2
 (2) Columbia County
○ Running InSync
 (3) Cobb County
○ Running SCATS
 Group recommended SCATS to ALDOT
front office for initial implementation in AL
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8. ALDOT Initial
Implementation
 (1) Montgomery
 Southern Boulevard/Eastern Boulevard
 (2) Birmingham area
 US-280 3
2
1
 (3) Huntsville
 Governors Drive
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9. Signal Timing Methods
 Free/Isolated
 Time Based Coordination
 Traffic Responsive
 Adaptive Control
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10. Adaptive Control – How?
 The tactics of different systems work
different ways, however…
 The general idea is that data being
collected by the vehicle detectors is
being used in real time to determine the
signal timings.
 Wide range of % reductions in delay
reported by various adaptive signal
controls
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11. SCOOT
 Split Cycle Offset Optimization Technique
 Used worldwide, a lot in Great Britain
 Uses data from advance detectors, models
progression from detector to stopline
 Factors for queuing
 Central server and on-street firmware
 Requires communication
 Need computer programming background
to understand system commands required
to operate and maintain the system
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12. InSync
 Rhythm Engineering
 Plug-and-play
 Controller set in free mode using
existing firmware
 Detector data taken, analyzed, and
sends calls to controller
 Requires communication
 Newer program, still customizing on the
fly to meet customers needs
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13. SCATS
 Sydney Coordinated Adaptive Traffic System
 Originated in Australia, found worldwide,
about 1/3 are in Australia
 Uses stopline video detection (6 x 15 zones)
to detect/measure gaps
 Central server selects pre-determined
cycle/split/offsets
 Communication required
 Synchro still needed!
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15. SCATS (Cont’d)
 Certain models of controller are required to
run SCATS
 US-280 getting Eagle M50 model
 Governors Drive getting 2070
 SCATS firmware installs alongside
traditional firmware on street controller
 Any mode of detection works, but video is
recommended
 Engineering design element of project is
generally required for implementation of
equipment modifications
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16. “Never retimed” to
“Adaptive”
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17. “Retimed” to “Adaptive”
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18. Savings
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19. Adaptive vs. TOD
140
120
100
80
Adaptive Cycle
60 TOD Cycle
40
20
0
12 2 4 6 8 10 12 2 4 6 8 10 12
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20. ALDOT Project Status
 Montgomery
 PS&E held Jan 4
 May 25 2012 Project Letting
 Birmingham
 PS&E is Jan 26
 May 25 2012 Project Letting
 Huntsville
 PS&E TBD (Feb 8 or Feb 9)
 May 25 2012 Project Letting
 ALDOT Transportation Director wants all
implemented by June 2012
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