Transit Signal Priority: The Importance of AVL Data David T. Crout Tri-County Metropolitan Transportation District of Oregon (TriMet) Presented at Transportation Research Board 83 rd Annual Meeting Workshop on Signal Control Priority for Transit Vehicles January 11, 2004

Transit Signal Priority: The Importance of AVL Data2 Project Partners

Transit Signal Priority: The Importance of AVL Data3 Increase person trips through selected traffic corridors while minimizing impacts on minor movements. Reduce transit running times. Improve transit schedule reliability: –Reduce running time variability. –Reduce excess time built into schedule to offset variability. Defer providing additional transit capacity. Tri-Met’s TSP Goals

Transit Signal Priority: The Importance of AVL Data4 Five traffic corridors now activated within the City of Portland. –180 signals activated. Now focusing on individual intersection “hot spots.” –Intersections analyzed for disproportionate delays to transit. –Anticipate approximately 120 additional intersections by early Project Status

Transit Signal Priority: The Importance of AVL Data5 TriMet AVL System Two Types of Data Collected Stops Data (Automatically Collected) - Information collected at each bus stop - Approximately 500,000 records per day Event Data (Operator Generated Data) - Special events at various locations - Approximately 25,000 records per day

6 Stops Data Bus Stop Location Actual Arrive Time Actual Leave Time Scheduled Time Dwell Door Opened Ons & Offs (APCs) Passenger Load Lift Usage Operator ID Maximum Speed Pass up Overload Traffic Delay Train/Bridge Delay Fare Evasion Graffiti/Vandalism Event Data

Transit Signal Priority: The Importance of AVL Data7 AVL System tracks bus location and schedule status. If conditions are met, bus emitter (Opticom) communicates priority request to signal. Signal controller then grants priority request. TriMet TSP Overview

Transit Signal Priority: The Importance of AVL Data8 Emitter Activation Conditions

Transit Signal Priority: The Importance of AVL Data9

10 Comparison of transit performance from before TSP activation to after. Relies on AVL: –Locational and temporal performance data is currently collected for all bus routes and at every bus stop. –Schedule adherence as well as travel time between stops can easily be determined. –Since distance between stops is known, gross speeds (i.e., including stops) can be calculated. Evaluation Methodology

Transit Signal Priority: The Importance of AVL Data11 Location & time bus starts and stops meeting TSP thresholds is also recorded. TSP analysis segments defined as bus stop pairs in the vicinity of one or more signalized intersections. –Performance in areas affected by signal(s) can then be analyzed. –Separate segments are necessary for each direction. –Means of incorporating TSP analysis into GIS. Evaluation Methodology

Transit Signal Priority: The Importance of AVL Data12 Intersection Analysis Route 4 – Division, SE 82nd Ave. & SE Division St.

Transit Signal Priority: The Importance of AVL Data13 Intersection Analysis Route 4 – Division, SE 82nd Ave. & SE Division St.

Transit Signal Priority: The Importance of AVL Data14 Trip-Level Analysis *Prior to Implementation of TSP.

Transit Signal Priority: The Importance of AVL Data15 Preliminary Results Travel time reduction of 2-3 minutes achieved after TSP implementation on Line 12, a high frequency trunk line. –Potential annual operating cost saving of $13,000. June 2002 schedule re-written to remove one bus on Line 4 due to travel time and variability reductions. –Estimated annual operating cost savings of $60,000. –Estimated one-time capital cost savings of $300,000.

Transit Signal Priority: The Importance of AVL Data16 Any Questions? David T. Crout