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Implementation Transit Priority System and Mobile Internet Passenger System in the City of Los Angeles. Presentation at the ITS America’s 2007 Annual Meeting June 4, 2007. Kang Hu and Chun Wong City of Los Angeles Department of Transportation. Metro Rapid System Map. Metro Rapid Program.
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Implementation Transit Priority System and Mobile Internet Passenger System in the City of Los Angeles Presentation at the ITS America’s 2007 Annual Meeting June 4, 2007 Kang Hu and Chun Wong City of Los Angeles Department of Transportation
Metro Rapid Program • 4 new lines per year • Completed Metro Rapid lines (17 corridors)
Metro Rapid Program • Future Rapid Lines • With a goal of 27 corridors by end of 2008
LADOT’s Transit Priority System (TPS) • A centralized signal priority system • Fully integrated with the City’s Adaptive Traffic Control System (ATCS) • Reduce bus delays at signalized intersections with minimal impacts on cross streets – “smart” priority • Provide real-time bus arrival information • Track bus performance throughout the system
Bus Detection • Selected loop-transponder based on field tests of 3 different technologies • Inductive loops placed in the roadway serve as antennas to receive bus transponder identification code • Advance (check-in) detector just past upstream bus stop • Release (check-out) detector just prior to limit line or within the intersection
Bus Transponder Transponder
Bus Priority Operation • EARLY GREEN - Phase is started earlier than normal to minimize delays to stopped or approaching buses • GREEN EXTENSION - Phase continues past normal endpoint to help buses pass through critical intersections • PHASE HOLD - Phase held in green until bus arrives, typically used for left turns.
Central System Architecture TPS Server (Transit Priority Manager) TPS Workstation Comm. Network LAN/WAN Sensor Input 2070 Controller Sensor Input 2070 Controller Sensor Input 2070 Controller Database Web Server
MTA’S Bus Dispatch Center • Monitor bus performance • Radio communication with bus operators • Real time bus dataprovided by LADOT • ATSAC video & camera control access
TPS Real-Time Data Collection Signal Priority Transit Priority Manager (TPM) Real-time Data Logging Transit Report And Query (iTRAQ) Web Server Real-time Graphical Displays
TPS Performance Benefits • Analyzed more than 2000 bus trips and run time data along the corridors • The Metro Rapid Buses achieved a 25% reduction in total travel time • Transit Priority System alone contributed to 30% of the total travel time saving • Bus delays at signalized intersections were reduced by 33-39% • Minimal impacts on cross street traffic
Impacts on Cross Traffic • Average of 1 second per vehicle per cycle increase in delay to the cross traffic • Change was measured over three time periods: AM, midday and PM peaks • The Level of Service did not change as a result of the Transit Priority System • At some locations timing was changed to provide additional cross street green time
Passenger Information System • Developed by LADOT • Based on bus detection • Uses actual travel time • Accurate to 1 min
Lessons Learned • Start with a demonstration project first before full implementation • Use proven technologies and keep it simple • Design to minimize impacts on cross street traffic • Do not underestimate the local controller software work and the interface with existing traffic control systems • Be ready to compromise on bus stop locations