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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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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