OPAC Adaptive Engine Pinellas County Deployment Farhad Pooran Telvent Transportation North America Baltimore Regional Traffic Signal Forum May 25, 2011
Presentation Agenda Adaptive control systems - expected benefits An overview of OPAC Case Study Pinellas County Project 2
Expected Benefits Mitigate effects of the capacity reduction through efficient use of the existing capacity (Proactive traffic management) Adjusts to traffic fluctuations and surges Continuously adjust signal timing parameters Reduce stops/delay, fuel consumption, and emissions 3
Adaptability - Cycle Optimization Mill Plain Blvd / 104th-105th Ave 200 190 180 170 Vehicle Counts 160 150 140 OPAC Cycle Length (Sec) 130 120 110 100 Pretimed Cycle Length (Sec) 90 16:30 16:34 16:38 16:44 16:49 16:54 16:59 17:04 17:09 17:15 17:20 17:27 17:33 17:38 17:43 17:48 17:52 17:56 18:00 18:05 18:11 18:16 18:21 18:26 Time 4
Adaptability - Cycle Optimization Cycle (sec) 200 190 180 170 160 150 140 130 120 110 100 7:007:308:008:309:009:3010:0010:3011:0011:3012:0012:3013:0013:3014:0014:3015:0015:3016:0016:3017:0017:3018:00 Time of Day 4500 4000 3500 3000 2500 2000 1500 1000 500 veh/hr TBC OPAC Total Volume 5
Adaptive Control Systems Design Fully Adaptive vs. Partially Adaptive Centralized vs. Distributed Proactive vs. Reactive Traffic Responsive (TRSP) is not an adaptive system 6
OPAC Adaptive Control Optimized Policies for Adaptive Control (OPAC) A fully adaptive, proactive, and distributed real time traffic control system Deployed as part of FHWA 1992-1995 RT-TRACS program 7
OPAC Fundamental Features Optimization of any or all phase splits designed to minimize total intersection delay and/or stops Support for phase skipping in the absence of demand Multiple sets of configuration parameters for customizing the resulting timing to weight certain movements for special circumstances or by time of day Configurable to respond to changes in left turn lead/ lag phasing by time of day Special considerations for phase timing in the presence of congestion (high detector occupancy) 8
Control Layers in OPAC Coordination Layer Split Distributed to each intersection Offset Distributed to each intersection Cycle Length Section-wide; calculated at central Background cycle (Dominant intersections) 9
Performance Measures Real-time estimates of phase-specific parameters such as queue length, speed, travel-time from detectors to standing queues, delay and stops Logged measures of effectiveness, including average cycle lengths, vehicle counts by phase, and average phase green times and estimated speeds. 10
Data Requirements Upstream detectors on each lane Once/sec vehicle count and occupancy data 11
Hardware Requirement Advanced traffic controllers, NTCIP (e.g., 2070 or NEMA TS-2) Communication media: copper, fiber, wireless Serial or Ethernet communications Local processor board (Distributed system) 12
Integration with Current Infrastructure Traffic Management System 13
Case Study City of Clearwater, Pinellas County, FL 25 intersections along US-19 Corridor 29 intersection along McMullen Booth Corridor 7 intersections along 49 th St (to be installed this year) Initial Deployment: 2006 Installed as part of FHWA 1996 RT-TRACS project Currently runs OPAC and RHODES under MIST platform 14
Project Area 15
Communications Communications Initial deployment: serial comm Communication media: fiber Converted to Ethernet based comm since 2010 Detections Technologies: Magnetic loops, RTMS, Sensys Signal System Platform MIST traffic management platform 2070 controllers with Econolite ASC/3-2070 firmware 16
Success of the system * Independent before/after study to determine the RT- TRACS software operation versus traditional time-of-day signal plans started October 2006 and was completed in 2007 Study determined that OPAC US19 travel times were reduced by an average of 7.5%, with peak travel times dropping 25% The results determined there was over $1 million in annual fuel savings alone as a result of the new system, and a benefit/cost ratio of approximately 7:1 * Courtesy of Pinellas County Public Works 17
Success of the system * (don t stop there!) 2008 changes to adaptive parameters resulted in an additional reduction of 10%, on average, to the travel times across the corridors What about safety? Total accidents are down by 30%, pre-adaptive year crash data vs. post-adaptive year crash data Rear-end accidents decreased by 18% Serious injuries have been reduced by 40% * Courtesy of Pinellas County Public Works 18
Green Corridors: Adaptive Control and Air Quality Traditional approach: travel time & stops/delays Environmental evaluation: Air quality parameters 19
Initial Results: OPAC Adaptive vs. TOD Particulate Matter (PM) PM Weekly 45 40 PM (micro grams/m3) 35 30 25 20 15 10 5 0 Avg Weekly Improvement: 17.56% OPAC 3/2-3/8 TOD 3/9-3/15 Day & Time 20
Initial Results: OPAC Adaptive vs. TOD Carbon Monoxide (CO) CO Emission - Weekly 14 12 OPAC 3/2-3/8 TOD 3/9-3/15 10 CO (ppm) 8 6 4 2 Avg Weekly Improvement: 11.04% 0 Day & Time 21
Conclusions Growing interest in deployment of adaptive signal systems Proven technologies for effective arterial corridor management Enhanced features utilizing on going advancements in communication systems, detection technologies and traffic control devices Given the appropriate technical staff and an eagerness to learn, one cannot deny the benefits adaptive signal control software can provide. Pinellas County Public Works 22
Thank You Farhad Pooran, Ph.D., P.E. Vice President, Engineering Telvent Transportation North America Rockville, Maryland Phone: +01 301 354 1376 E-mail: farhad.pooran@telvent.com