T3 Webinar:
4/16/2008 - Assessing the Potential for BRT in Your Region: Lessons Learned from a Los Angeles/New York ITS Peer-to-Peer Exchange
April 16, 2008
Text version of Webinar presentation:
"Transit Priority Systems (TPS)"
Description of image or images on a slide contained in brackets.
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Slide 1: Transit Priority Systems (TPS)
T3 Webinar on Bus Rapid Transit Webinar
April 16, 2008
Chun Wong, P.E.
City of Los Angeles, Department of Transportation
Slide 2: "Smart" Transit Priority System (TPS)
[Image of a bus, a traffic signal, and a light bulb. The slide indicates that Transit Priority System is a combination of equipment (bus), hardware (signal) and ingenuity (light bulb). ]
Slide 3: Project Overview
- LADOT partnered with LA Metro in National Bus Rapid Transit (BRT) Demonstration Program since 2000
- Wilshire/Whittier & Ventura
- Strong Mayor commitment to improve LA transit services
- Improve bus run time performance
- Improve ridership
- Successfully implemented 18 Metro Rapid bus corridors and the Metro Orange Line
- Reduced 25% total travel time
[Images: Computers and desks in a Transportation Management Center. Image of front of bus in traffic.
]
Slide 4: Project Objectives
- Provide schedule adherence
- Operate within existing street infrastructure
- Minimize cross street impact
- Provide bus arrival information
- Improve transit experience
Slide 5: Existing Infrastructure
- City’s central Urban Traffic Control System (UTCS) - ATSAC
- One-second communication poll
- Type 2070 traffic controllers
[Image of man sitting at a terminal in a Transportation Management Center.
]
Slide 6: LA Transit Priority Systems Solution
[Images of devices used LA’s transit priority signal system. Includes a transponder affixed to a bus bumper, a loop detectors embedded in a road, a 2070 controller, and communications center. These images surround a center image of an intersection equipped for transit priority. The image shows a bus headed toward the intersection, transmitting signals to the traffic signal controller.
]
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Slide 7: TPS Components
- Inductive loop/transponder detection
- Low frequency hockey puck liked transponder
- Curb-to-curb elongated loop sensor
- Model 2070 traffic controller
- Check-in / Check-out detection
- ATSAC communication network
Slide 8: Transit Priority Manager
- Centralized System
- PC based server
- Real-Time
- Track vehicle positions
- Determine late/early
- Issue signal priority
- Calculate bus arrival
- Publish bus data
- Retrieve run time data
- Implement TOD headway plan
- Non Real-Time
- Archive to database for trip analysis
[Image: Screen host of Transit Priority Manager system. ]
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Slide 9: Preemption ≠ Signal Priority
- Preemption
- Interrupt signal operations
- R x R crossings
- Emergency vehicles
- Signal Priority
- Modify signal operations
- Maintain coordination
- Borrowed time (10% of cycle length)
Slide 10: Priority Treatments
- Early green
- Vehicle detection required
- Red truncation
- Green extension
- Vehicle detection required
- Extend green phase
- Most efficient priority
- Call Phase
Slide 11: Headway Algorithm
- In-house developed
- High bus frequency service – low headway
- Leverages Hot List / Run List
- Time-point propagation (TPP)
- Load-balanced
Slide 12: LADOT Transit Priority Systems (TPS)
[Images of a Metro Rapid Buss, Metro Orange Line bus, street-embedded bus sensor, transponder, iTRAQ website, graphics display, passenger information system, a traffic signal, and a mobile internet passenger system. All of these images surround a center image, which is a screen shot of the TPS computer-based system. The slide shows that information is exchanged between the central system and devices I the field.
]
Slide 13: Multi-jurisdictional TPS
- Countywide BSP (Bus Signal Priority) Program
- WiFi 802.11b
- On-board GPS tracking
- Distributed system
[Image of intersection equipped for transit priority signal operations. Thumbnail image of map and location of LADOT Transit Priority Signals.
]
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Slide 14: BI-Tran 2033 & L.A. TPS
[Image of BI-TRAN 2033 & L.A. TPS schematic.
]
Slide 15: TPS Communication Option
[Image of TPS Communications Options schematic.
]
Slide 16: TPS Map Client Software
[Image of TPS map client software. Shows dialogue boxes displaying Bus Arrival Times, Traffic Controller Status, and Bus Runtime Info.
]
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Slide 17: Passenger Information System
- Real-time data
- Integrated with TPM
- ETA Count down
- Lead bus’ travel time
- LED Displays
- Communication
- CDPD wireless by AT&T
- Hard-wired FSK (Frequency Shift Keying)
[Images of LED signs displaying passenger information.
]
Slide 18: Mobile Internet Passenger Systems (MIPS)
[Image of metro rapid website and a person holding a cell phone, indicating the availability of the Mobile Internet Passenger System (MIPS).
]
Slide 19: TPS Real-Time Data Collection
[Images of devices in transit priority system real-time data collection. Includes a traffic signal, transit priority manager, real-time graphical displays, real-time data logging, and the Transit Report and Query (iTRAQ) web server.
]
Slide 20: i Transit Report And Query
- Leverages existing TPS architecture
- Field equipment (Loop/Transponder AVL, 2070 Controller, etc.)
- Automates 24 x 7 transit trip data collection
- Weekdays; weekends; holidays; rainy days, etc.
- Uses commercially standardized Relational Database system (RDBMS)
- Publishes through Web Server
- Simplify RDBMS data access
- Client workstations request no complicated ODBC and/or RDMBS setup
- In-house developed web application
- Microsoft IIS 6.0
- Performance Measure Tool
Slide 21: iTRAQ Web Interfaces
[Image of screen prints of iTRAQ computer interfaces.
]
Slide 22: Lesson Learned
- Transit and DOT partnership
- Existing infrastructure
- Budget constraint
- Must / desired features
- Operation / Maintenance cost
Slide 23: The End
Questions & Comments
Send questions to:
Email: chun.wong@lacity.org
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