1. Transit Signal Prioritization (TSP) Considerations within RTS Corridors Rapid Transit System Steering Committee
Technical Memorandum 2 Existing Conditions Signal Systems & Corridor Operations
December 17th, 2013

2. Key Findings
10 Route RTS network has 116 stations overlaying 284 existing traffic signals and 820 existing bus stops
Implementing advanced TSP within RTS requires close coordination of existing agencies and systems. Cannot be done in isolation.
Existing signal controllers/ central software currently does not support all advanced TSP functions
Would require time and cost to upgrade, cost TBD
Primary traffic control system function is to monitor signal performance for roadway safety and mobility
TSP is a secondary function within overall operations
Incorporating WMATA buses into RTS would require additional hardware and software, cost TBD
Council resolution shifts TSP decisions based on ROW treatment to Facility Planning stage

3. Priority Transit Corridors and Montgomery County Signals
Countywide Transit Corridors Functional Master Plan
Planning Board Draft (MNCPPC, July 2013)

4. Summary Table

5. Traffic Signals in Montgomery County by Ownership/Operation & Potential TSP Corridors

6. Traffic Signals in Montgomery County by Ownership & Operation
63% Owned by the State of Maryland
31% Owned by Montgomery County
5% Owned by the City of Rockville
91% Operated by Montgomery County
Approximately 30 of the MDSHA signals in and around Takoma Park & New Hampshire are not operated by the County
10 will migrate to County operations in the near future
15 are along New Hampshire Avenue (4 outside the County)
Majority of the Signals along the RTS routes are owned by MDSHA

7. Montgomery County Advanced Transportation Management System (ATMS)
Traffic signal operations key component of ATMS
Traffic Signal System Modernization Completed in 2012
New computer and servers
Custom traffic operations and ATMS Software
Upgrade of all MDSHA and County traffic signal controllers to modern Econolite ASC/3 controllers
High speed communications network for real time operations
Distributed signal control system (using the ASC/3 controllers)
Each ASC/3 controller is TSP ready (with $400 TSP data key)
Developed/tested recommended TSP Architecture:
Econolite ASC/3 controllers
GTT Opticom GPS Spread Spectrum TSP system
ORBCAD Transit Automated Vehicle Location/Computer Aided Dispatch

8. Montgomery County Recommended TSP Architecture
ATMS Operations Center
Transit Management
Traffic Management
ATMS Central Operations Software
ORBCAD Central Software
GPS
Traffic SIGNAL
Monitoring and logging data
AVL & Computer Aided Dispatch
Vehicle Tracking
& Detection 1
I Am HERE
Vehicle is in range
Who gets Priority
Signal Strategy to use
Priority Request Generator 2
Priority Request Server 3
ORBCAD Veh. Components: I am Late
I Want Priority 4
GTT Opticom
GPS TSP System
ASC/3 Signal Controller
Adjusted phases
In cycle

9. Recommended Countywide TSP Concept of Operations
Assumes Current Service
Transit vehicles in mixed flow without other priority measures
No differentiation between types of transit service
TSP Request when bus is more than 5 minutes late
TSP Granted on first come first served basis
TSP Signal Strategies
Green Extension
Early Green
Signal coordination allowed to “recover” between instances of signal priority
3 cycles between granting requests)

10. Issues of Concern to RTS from Current Systems Review (1)
Current Montgomery County System can implement:
Early green,
Extended green
Leading green for queue jumps
Other TSP Signal Strategies will be costly and require changes to the overall system (beyond firmware v 2.50)
GTT Opticom GPS TSP System
Recommended for Montgomery County and WMATA
WMATA's recommended system uses different communications.
WMATA System in Montgomery County
Need cellular modems at the roadside (cabinet) for each signal location
Tests to make sure inputs from Ride On and WMATA can work together

11. Issues of Concern to RTS from Current Systems Review (2)
Automatic Vehicle Location/Computer Aided Dispatch
Ride On ORBCAD AVL/CAD system tested for TSP in Montgomery County
Not Used by WMATA (Clever Devices)
AVL/CAD for RTS needs to be determined.
City of Rockville
No signals operated by Rockville directly on the RTS corridors
Two signals on CCT right of way  
Potential for TSP at Rockville signals with diversions to reach special destinations (e.g. Community College)
Any integration with the Rockville system will require upgrades to its controllers and/or central software. 
Integrating Current MTA Commuter Service (provided by contractors with no AVL/CAD) requires added technology
RTS will need to integrate/coordinate with CCT and Purple line.  

12. RTS ROW Priority Treatments versus TSP Signal Operations
* Insert Transit Phase, Phase Rotation, & Phase Suppression would require upgrade of Signal System Software

13. Other Characteristics impacting TSP (Turns, Other Service)

14. Factors influencing TSP Strategies at Specific Intersections
Roadway:
Intersection Level of Service
Available green time (slack)
Cross street facility type
Bicycle & Pedestrian treatments and priority areas,
Transit:
Other Transit Service in the Corridor
Cross street transit service
Bus stop/station locations
Service frequency
Time between priority requests
Ridership

15. Overall System and Policy Decisions Needed
Can’t determine TSP at specific intersections until facility planning for each corridor
Can/Should decide:
Integrated or separate
Operations centers
Communications
TSP systems and equipment
TSP Architecture (centralized, distributed, communications, etc.)
Recommended TSP by ROW Priority Treatment
Types of transit service receiving TSP in corridor
Decision strategy for enabling TSP and each intersection
Conditional parameters (direction, time of day, schedule, passengers, frequency of granting requests)
Types of TSP signal strategies to provide for
RTS and Purple Line integration

16. Technical Memorandum 3, RTS & TSP Findings & Recommendations:
What do we have today, what do we want to have in the future?
Cost to deploy all add-on TSP configurations within the current signal system
Concept of operations – defined scenarios with
RTS vehicles only
RTS and other transit providers in RTS ROW
RTS and conflicting local transit outside RTS ROW
RTS and conflicting LRV outside RTS ROW
What needs to happen for each type of strategy/ ROW
Technology, agency agreements, etc.

17. Back up Slides

18. Econolite ASC/3 Controller
Controls signal phasing, TSP strategy length of priority, lock out periods (16 phases max)
Current advanced controller offered by Econonlite
Compatible with Standards (NEMA TS2, NTCIP 2011)
1 TSP request addressed per cycle (check in/out or continuous monitoring)
TSP ready (with $400 TSP data key)
TSP Strategies with current firmware (v 2.45, planned 2.49)
Extended green
Early green
Leading green for queue jump
Additional features/strategies dependent on firmware v 2.50 and above
Firmware v 2.50 and above incompatible with ATMS Central Operations Software. Very costly to upgrade

19. GTT Opticom GPS TSP System
Recommended for Montgomery County existing system
Also selected by WMATA (with differences) and MDSHA in other areas (for preemption). On MDSHA procurement schedule.
Components/functions
On-vehicle (PRG: sends request when criteria are met)
Wayside antennae (spread spectrum) to receive vehicle location
Phase selector (PRS: validate position, in range ?, prioritize/resolve conflicts, send request to controller)
Additional central software to provide monitoring and logging data also recommended
Proved technically feasible in Route 55 MD 355 TSP test
How to integrate across operating agencies / services remains to be seen

20. ORBCAD AVL/CAD System
Automatic Vehicle Location and Computer Aided Dispatch system implemented by Ride On
Currently provided by ACS Systems/Xerox (has gone through several transitions)
Functions
Real time vehicle location and monitoring
Schedule and route adherence
Data and voice communications (mobile data terminal)
Voice annunciation for stops along routes
Silent alarm
Automatic Passenger Counts
TSP integration to identify late vehicles, passengers, etc.
Integration with TSP proven technically feasible in Route 55/MD 355 TSP test.

21. City of Rockville Signal System
143 signals within or near Rockville Boarders
City owns 48 signals
City operates:
42 of its own signals
6 of the MDSHA signals
Econolite ASC/2 Controllers with limited TSP capability
Aires Closed Loop traffic system with dial up connection (not real time)
No City Signals directly on RTS Routes
2 City Signals on the CCT corridor

22. Ride On Montgomery County Transit (Ride On)
Weekday service:
78 routes
289 peak vehicles
Provides service in every proposed RTS corridor
Operations colocated with traffic but not integrated
Trapeze bus scheduling and run-cutting software
Smart Traveler Customer Information
Regional Smart Card Fare Payment
Implementing Automatic Passenger Counters (~ 55%)
ORBCAD Avl/Cad system
Will allow Conditional TSP on Schedule Adherence and Passenger Loads
Only Route 55 TSP vehicles for TSP Test equipped with GTT Opticom GPS TSP systems

23. Washington Metropolitan Area Transportation Authority (WMATA)
From: A. Young Leveraging the WMATA CoABE Project Technology for TSP Implementation (ITS Maryland, October 2013)
Consolidated onboard & fixed end equipment in 2012/2013
Clever Devices AVL/CAD
GTT Opticom TSP software/ hardware
Cellular communications with the Intelligent Vehicle Network (IVN) Unit
Roadside (cabinet) cellular modem with GPS
Econolite ASC3 controller through GTT Phase Selector

24. Washington Metropolitan Area Transportation Authority (WMATA)
Service
140 Metrobuses in peak periods within Montgomery County
Primarily regional service along major corridors
WMATA service in every proposed RTS corridor
Issues
Installation, recurring costs, maintenance of cellular modems within Montgomery County signal cabinets
Reconciliation/integration between WMATA Cellular and Montgomery County Spread Spectrum vehicle to roadside communication (can inputs be received and integrate from both)
Resolving competing priority requests between Montgomery County and WMATA vehicles
Communication/coordination between operation centers

25. Maryland Transit Administration (MTA)
Current Service
Route Gaithersburg to BWI Marshall Airport
Route Metropolitan Grove to DOD/Ft. Meade
Route Columbia to Bethesda
Route Frederick to College Park
Route Columbia/Silver Spring to Washington, DC
Route Columbia/Silver Spring to Washington, DC
Route Hagerstown/Frederick to Shady Grove/Rock Spring Business Park
Route Clarksville/Ellicott City/Columbia to Washington, DC
Contract Service with no AVL/CAD or other technology requirements
Future Systems (will need to coordinate)
Purple Line
Corridor Cities Transitway (CCT)