1. INTEGRATING SIGNAL AND LANE CONTROL Edward Lieberman, P.E. Jinil Chang, Ph. D. 2006 Annual Meeting Panel 5: Emerging Technologies June 9, 2006

2. 2006 Annual Meeting - Panel 5: Emerging Technologies Basic Principles There are strong interactions among geometric configuration and signal timing plans which influence traffic performance Treating these elements as an integrated system can yield optimal, adaptive lane allocation and signal-timing plans that are responsive to changing conditions

3. 2006 Annual Meeting - Panel 5: Emerging Technologies

5. Intersection Design and Control Given1. Estimate traffic volumes, by movement ROW, Budget constraints Develop2. Approach configurations Rules: 100 vph, etc. Assert/3. Signal Cycle Length Compute4. Signal Phasing Plans Compute5. Signal Phase Durations 6. Signal Offsets A sequential “Waterfall” process

6. 2006 Annual Meeting - Panel 5: Emerging Technologies For a given approach width, it is possible to design a number of different lane-use configurations. For a given approach width, it is possible to design a number of different lane-use configurations. Each can support several [different] signal phases and durations. Each can support several [different] signal phases and durations. How can we determine the best combination of approach configurations, signal phasing plan and signal timing for all time periods?

8. 2006 Annual Meeting - Panel 5: Emerging Technologies Given, for every time period: Estimates of traffic volumes ROW, Budget constraints Over a selected range of signal cycle lengths… and for every viable Intersection configuration… Signal Phasing Plans Compute Signal Phase Durations Signal Offsets …and select the “best” design/lane allocation and control plan for each time period An integrated, exhaustive computational process Proposed Intersection Design Procedure

10. 2006 Annual Meeting - Panel 5: Emerging Technologies ILLUSTRATIVE CONFIGURATIONS 1 2 3 4 Case 3(a) Case 11(c) Case 3(a) Case 3(b) Configuration 1 Configuration 2 Restrict parking on east-west approaches.

11. 2006 Annual Meeting - Panel 5: Emerging Technologies Reference: Lieberman, E. and Chang, J., Ph.D., New Formulation to Analyze Signalized Approaches, paper presented at TRB, January 2006. www.kldassociates.com

12. 2006 Annual Meeting - Panel 5: Emerging Technologies

13. Evaluation 0 20 40 60 80 100 1.1 1.0 0.9 0.8 Better Solution Percent Left-Turns Protected Cycle Utilization Operations/Safety Metrics Oversaturated 0.7 1 2 3 4 5 4 6 8 1 2 3 5 7 C = 90 sec. Configuration 1 Configuration 2 Locus of Optimal Solution Configuration 1 Configuration 2

14. 2006 Annual Meeting - Panel 5: Emerging Technologies Summary 1. We can evaluate combinations of approach configurations, signal phasing and timing plans for different time periods. 2. We can extend adaptive control to include dynamic lane allocation responsive to changing traffic demand patterns over the course of a day.