1. ACS Lite Overview – NTOC Webinar Aug06 U.S. Department of Transportation Federal Highway Administration FHWA Contract No.DTFH61-02-C-00047 Slide 1 ACS-Lite Adaptive Control Software for Closed-loop Traffic Control Systems Raj Ghaman, P.E. Operations Team Leader FHWA RD&T

2. ACS Lite Overview – NTOC Webinar Aug06 U.S. Department of Transportation Federal Highway Administration FHWA Contract No.DTFH61-02-C-00047 Slide 2 Adaptive in the U.S. (FHWA) 1970s-1980s: UTCS / TRPS –Second by second central 1990s: Predictive control (ACS) –FHWA ACS: RHODES, OPAC, RTACL –Second by second distributed 2002: Controller-based Adaptive –FHWA ACS Lite –Leverage existing hardware / infrastructure –Download new controller parameters every five-fifteen minutes

3. ACS Lite Overview – NTOC Webinar Aug06 U.S. Department of Transportation Federal Highway Administration FHWA Contract No.DTFH61-02-C-00047 Slide 3 FHWA Goals for ACS-Lite Low cost design Leverage existing infrastructure Standard US-style actuated controllers and logic (rings, phases, splits, barriers, gap- out/extension, etc.) Standard fully-actuated detector layouts Standard NTCIP Communications Retro-fit with major US signal system vendors

4. ACS Lite Overview – NTOC Webinar Aug06 U.S. Department of Transportation Federal Highway Administration FHWA Contract No.DTFH61-02-C-00047 Slide 4 Project Team

5. ACS Lite Overview – NTOC Webinar Aug06 U.S. Department of Transportation Federal Highway Administration FHWA Contract No.DTFH61-02-C-00047 Slide 5 Field trials Peek/Quixote Bradenton (St. Petersburg/Tampa), Florida Econolite Gahanna (Columbus), Ohio Eagle/Siemens Houston, Texas McCain El Cajon (San Diego), California

6. ACS Lite Overview – NTOC Webinar Aug06 U.S. Department of Transportation Federal Highway Administration FHWA Contract No.DTFH61-02-C-00047 Slide 6 Gahanna, OH field test results Results - Number of Stops

7. ACS Lite Overview – NTOC Webinar Aug06 U.S. Department of Transportation Federal Highway Administration FHWA Contract No.DTFH61-02-C-00047 Slide 7 Gahanna, OH field test results 1 Peak hours = Average savings*(Average Corridor Peak Hour Volume*4 peak hours) Unit Costs: Total Delay – $12.10 per hour Stops – $0.014 per stop Fuel Consumed – $0.59 per liter ($2.25 per gallon) Before (per veh) After (per veh) Savings (per veh) Peak Hours (all vehs) Peak Hours Savings Total Delay (hour)0.037610.037580.000030.15588$1.89 Total Stops3.52.90.63117.6$43.65 Fuel (Liters)0.3900.3730.01789.287$53.08 Peak Hours Benefit $98.61 Daily Benefit $340.03 Annual Benefit $88,500.00

8. ACS Lite Overview – NTOC Webinar Aug06 U.S. Department of Transportation Federal Highway Administration FHWA Contract No.DTFH61-02-C-00047 Slide 8 Houston, TX field test results Results - Travel Time

9. ACS Lite Overview – NTOC Webinar Aug06 U.S. Department of Transportation Federal Highway Administration FHWA Contract No.DTFH61-02-C-00047 Slide 9 Houston, TX field test results Before (per veh) After (per veh) Savings (per veh) Peak Hours (all vehs) Peak Hours Savings Total Delay (hour)0.018560.012140.0064239.16252$473.87 Total Stops1.71.20.53051.6$42.72 Fuel (Liters)0.4900.4550.035214.837$127.71 Peak Hours Benefit $644.30 Daily Benefit $2,221.72 Annual Benefit $577,648.12 Unit Costs: Total Delay – $12.10 per hour Stops – $0.014 per stop Fuel Consumed – $0.59 per liter ($2.25 per gallon)