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Charlie Wetzel, PE, PTOE County Traffic EngineerSeminole County Florida

10/18/11

• Who is Seminole County? • Why SynchroGreen?• SynchroGreen Basics• SR 436 Project• Future Projects• Questions

Outline

210/18/11

• County located between Orange County (Orlando), Volusia County (Daytona Beach) and Brevard County (Cocoa Beach)

• Population: 422,718 (2010)• Area: 345 sq. miles• 7 Cities• Varying traffic – tourists, events, retail,

business

Who is Seminole County?

310/18/11

• Traffic signals – own/partially own 240, maintain 370 (all but 7 in the County)

• Communications – 99% with comm., 33 signals on radio, rest on fiber (350+ miles), 4 with no comm.

• Detection – primarily loops, 8 with full video, 12 with partial video (adaptive project)

• Controller equipment – Naztec NEMA TS2, ATMS.Now central software

• Staff – 9 in Signal Section, 7 in Fiber Section • Retiming activities – goal once every 3 years, funding:

$190k from MPO, $150k from County funds• ATMS Grants (MPO/FDOT) - $3M in 1999, $4M in 2011

Who is Seminole County?

410/18/11

• Looking for alternatives to TOD plans – varying traffic, pedestrian and pre-emption issues

• Waiting for developments in adaptive, as opposed to going responsive

• Only other adaptive in the area is SCOOTS in Orange County (mixed results)

• Familiar with Trafficware - we use SynchroTM and SimTrafficTM

• Learned that Naztec and Trafficware wanted to team up and we offered to implement and test the first SynchroGreen system

Why SynchroGreen?

510/18/11

• Utilizes standard NTCIP • No hardware – no “black box” or anything needing FDOT

approval• Uses SynchroGreen “MIB” inside the controller• Adjusts signal timings based on real-time traffic • Can use existing infrastructure (controllers, detection)• Can turn on/off by time-of-day• Will revert to time-of-day plan when off or loss of comm.• Considers overall network delay; not just main street

SynchroGreen Basics

610/18/11

• Uses central WindowsTM based PC or server

• Collects detector data from local intersections– Occupancy (stop bar detection)– Platoon behavior/distribution (free

flow detection)• Communications via Ethernet• Performs calculations to

determine optimal timing parameters

• Uploads timings and continues to monitor local intersections

SynchroGreen Basics

710/18/11

• Can turn on/off adaptive mode instantly• Local controller setup is minimal

(existing settings remain – phase and clearance times)• SynchroGreen does not modify sequences; this is

handled by background time of day sequences • Detection:

– Any reliable technology (loops, video, wireless, radar)– Stop bar

• All lanes must have stop bar detection– Advanced (free flow)

• Advanced detection on main street only• Behind 85th percentile queue

SynchroGreen Basics

810/18/11

• Splits – Phase Allocations• Cycles – Periods• Offsets – Start Times

Optimization

910/18/11

• Occupancy of detection zone is measured during the effective green of that phase yielding a green utilization

• Detector calibration factor, based on characteristics of detection zone (length, type, grade), is applied to green utilization

• Target (desired) phase allocation is then calculated in real-time

Optimization - Phase Allocations

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Optimization – Periods

Sample phase targets used to determine the period plan (cycle) below

Note that 149 second period was selected for all locations based on the target value of the highest intersection

10/18/11

• Adjusted based on platoon behavior/distribution using advanced detectors

• Transition-less adjustment• Start times recalculate due to:

– Period changes– Traffic flow changes

• Lag Time – Reacts to queues– Reacts to platoon arrival

Optimization - Start Times

1210/18/11

• SynchroGreen Balanced Mode– Minimizes network delay

• SynchroGreen Progression Mode– Favors progression along the corridor

• SynchroGreen Critical Movement Mode– Focuses on critical movements, while minimizing delay

Optimization Strategies

1310/18/11

Interface

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STARTUP

MONITOR

SETUP

10/18/11

• Integrates with SynchroTM and SimTrafficTM

• Can model adaptive traffic control• Calibrate adaptive settings before deployment• Compare adaptive system to TOD operation

Simulation

1510/18/11

• 12 Signalized Intersections on State Road 436 • Previously actuated/coordinated system• 1.7 miles• 59,600 ADT• Heavy Pedestrian Activity (>1,100 peds/day)• Preemption requests (>150 requests/day)• Challenging corridor to test SynchroGreen

SR 436 Project

1610/18/11

SR 436 Deployment

1710/18/11

• Deployed May 2011• Naztec 980 TS2 Controllers• Used existing inductive loops

(side streets and left turns)• Installed new video detection

(main street stop bar andadvanced)

• Received in-field training on operation and calibration

SR 436 Deployment

1810/18/11

• Travel Time (AM: -6%, MD: -26%, PM: -12%)• Delay (AM: -12%, MD: -42%, PM: -19%) • Stops (AM: -25%, MD: -36%, PM: -20%)• Side-street Delay (-19% ave. at 2 sample locations)• Environmental MOEs

– Fuel consumption (AM: -10%, MD: -22%, PM: -12%) – HC, CO, NOx Emissions – similar to other results

• All determined using Tru-Traffic, with exception of side-street (HCM)

SR 436 Before/After Study

1910/18/11

SR 436 Results

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AM 150 -> 142MD 160 -> 141PM 200 -> 155

10/18/11

• Traffic conditions were difficult; however, SynchroGreen showed improved operations (decreased travel time, delay and stops)

• Greatest improvements during non-peak periods• Significant improvements for pedestrian and pre-

emption transitions• We are still experimenting with the system. • Many options haven’t been tried yet (start time

modifications, different mode types, calibration using Synchro and SimTraffic)

• Expanding SR 436 by 4 additional signals

SR 436 Project Summary

2110/18/11

• Base price - $13,500 per intersection• Initial Corridor Setup/Training – Varies depending on

# signals/complexity, available Synchro models, etc. ($5k to $12k)

• Extras:– Additional training (estimate $7,500)– Server (estimate $8k)– Before/after studies (estimate $5k)– Detection (varies)

SynchroGreen Costs

2210/18/11

• Implementing on other corridors (Lake Mary Blvd, SR 46, CR 46A, US 17/92 and other sections of SR 436).

• Installing at 43 additional locations using our $4M grant

• Considering alternate detection methods (wireless, loops)

• New loop standard in the County to accommodate adaptive

• Working with Bluetooth technology to monitor the corridor

Future Projects

2310/18/11

Questions or Comments

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Charlie Wetzel, PE, PTOE cwetzel@seminolecountyfl.gov

10/18/11