1 / 20

SIGNAL TIMING WITHOUT TRAFFIC COUNTS

SIGNAL TIMING WITHOUT TRAFFIC COUNTS. Presented by Jim Poston Regional Transportation Commission of Washoe County. Zong Z. Tian , Ph.D., P.E. University of Nevada, Reno. http://unr.edu/homepage/zongt/. Overview. Signal timing practice Case study My magic tool Results Conclusions.

aoife
Download Presentation

SIGNAL TIMING WITHOUT TRAFFIC COUNTS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. SIGNAL TIMING WITHOUT TRAFFIC COUNTS Presented by Jim Poston Regional Transportation Commission of Washoe County Zong Z. Tian, Ph.D., P.E. University of Nevada, Reno http://unr.edu/homepage/zongt/

  2. Overview • Signal timing practice • Case study • My magic tool • Results • Conclusions

  3. Signal Timing Practice • Turning movement counts (15-30% total cost) • Computer model and timing optimization (50~70%) • Field implementation and fine tune (10~20%) • Timing maintenance (<5%)

  4. Coordination parameters • Cycle length • Phase sequence • Phase split • Phase offset

  5. What Is Really Needed? • Phase demand/split • How to obtain phase split • estimate based on volumes • existing timing • controller log • Existing splits are generally good if no cycle change is needed

  6. NB Intersection and distance

  7. Real-world Issues • Variable speeds • Early releases • Wrong offset reference • Start or end of coordinated phases • TS2-1st Green or First Ring • Signal out of coordination • Preemption • Pedestrian • Loss communication • Clock time

  8. Cycle = 120

  9. NB

  10. Before-After After Total = 4’04” Before Total = 6’15”

  11. Before-After After Total = 4’04” Before Total = 6’15”

  12. SMRTSignal Monitoring & Retiming Tool

  13. GPS

  14. SMRT

  15. SMRT

  16. SMRT

  17. CONCLUSIONS • Signal timing can be done without traffic counts (15%+ saving) • Significant improvement by simply changing phasing sequences • 15% travel time saving • 20~80% saving in stops • My magic “Timer”

  18. ?

More Related