Pennoni Perspective Volume 22 • Issue 4 • Winter 2018/19 - Page 17

SOLUTION ATSC systems are regarded as the most effective technology for improving signal coor- dination and vehicular progression. ATSC systems better accommodate varying traffic volumes and changing demand patterns throughout each hour of the day and day of the week (i.e., peak and off-peak hours, weekdays and weekends). Under ATSC opera- tion, the improved traffic flows lead to fewer stops and less disparity in traffic speeds; reduced delays causing less driver frustration and thus safer driving behavior; and reduced queueing which results in less opportunity for rear-end crashes. Out of five prospective “off-the-shelf” adaptive technologies, the In|Sync system was ultimately chosen by the stakeholders for deployment in the US Route 15 corridor. In|Sync does not depend on a central server to run adaptive operations. In|Sync uses a web-based software application that allows authorized users from Lewisburg Bor- ough, East Buffalo Township, and PennDOT District 3-0, remote access to the system from anywhere at any time. In|Sync employs true dynamic signal phasing and vari- able period lengths, allowing the system to call up a pair of non-conflicting phases in response to real time demand, thus enabling the signals to use green time more efficiently, getting motorists to their destinations faster. In|Sync can be restricted to conventional phasing only if required by the system owner. Vehicular detection for the US Route 15 ATSC system was achieved using thermal video detection devices mounted on signal mast arms. Adaptive processors, pedes- trian modules, and other related devices required for the adaptive operation were installed in new signal controller cabinets, as requested by the client. The adaptive hardware was installed using the existing signal infrastructure, completely eliminating the need for costly and time-consuming Right-of-Way acquisitions. Supplemental un- derground conduit lines were constructed where existing lines did not have enough capacity to install the additional wiring associated with the ATSC components, and other miscellaneous signal upgrades installed as part of the project. Traffic signals were interconnected by means of broadband wireless communication antennas in- stalled at each intersection. An Internet modem was installed at the US 15 and PA 45 facilitator intersection, so that the local Internet Service Provider could deliver high-speed Internet service for a fully functional, corridor-wide, Ethernet-based com- munications network. This network is remotely accessible through PennDOT’s Virtual Private Network. R E S U LT S The In|Sync system deployed in this project replaced a conventional signal system that was not operating consistently as an effective coordinated system. “Before and After” adaptive implementation travel time data were collected along the US Route 15 study corridor. The results indicate that traffic flow during the weekday morning and evening peak hours of the day significantly improved after adaptive operations were implemented. For example, the average morning southbound travel time for the “Before” adaptive scenario was 133 ± 19 seconds, while the average travel time for the “After” adaptive scenario is 78 ± 6 seconds – a significant 41 percent reduction. The average number of stops also noticeably decreased for each peak hour period and travel direction. In all cases, once the adaptive operation was activated, the aver- age number of stops experienced by motorists traversing the corridor were reduced by at least 50 percent of what they were in the “Before” scenario. Technological advancements are allowing us to provide more efficient automated adaptive traffic control in this congested corridor. By applying ATSC technology, the owner is anticipated to reduce the cost and time involved in traffic signal retiming. Additionally, the system-wide live camera feeds, and robust monitoring and alarm capabilities, are expected to noticeably facilitate operations, management, and main- tenance of the US Route 15 signalized system. P E N N O N I | 17