signalized intersection performance measurement vendor perspectives regarding indot/purdue/vendor...
TRANSCRIPT
Signalized Intersection Performance Measurement
Vendor Perspectives Regarding INDOT/Purdue/Vendor Collaborative Project
Eric RaamotVice President, [email protected]
Presented by: Gary DuncanSr. Vice President and Chief Technology [email protected]
Discussion Points• Brief summary of historic intersection
performance measurement
• Overview of the successful Academic/DOT/Industry collaboration used to research enhancements on performance measurement
• Outline of Product enhancements derived from research
Historical Challenges• Typical field data collection has been limited to:
– Volume– Occupancy– Average speed – Data averaged over relatively large aggregation periods
• Typically 5 - 60 minutes
• Controllers have provided some basic MOE logging:– Phase split duration– Reason for termination (Max/Gap/Force Off) – Pedestrian actuation– Transition begin/end– Preemption begin/end
Example of Current MOE’s
0:00 6:00 12:00 18:00 24:00
Time of Day
20%
40%
60%
80%
100%
Occ
upan
cy
Historical Challenges• Gap exists between collection of “data” and generation of
“information”• Translation from data into information has typically been
left up to the traffic engineer.• Limitations within controllers based upon size of controller
memory and low-bandwidth communications infrastructure have limited data collection in the past.
• Current technology opens the door for more extensive logging as well a conversion of data points into useful traffic engineering information.
Agency Resources
• Many agencies do not have the resources to retime all intersections every 1-3 years.
• Little system-level information exists to identify intersections operating with outdated or problem timing.
• Challenge is to use capabilities of today’s controllers and systems to create tools that reveal opportunities for performance improvement.
INDOT /Purdue Instrumented
Intersections (2003)
Econolite ASC/3 Data Logger (2006)
Research Chronology
…
ASC/3 Data Logger
• 100msec time-stamping of all relevant controller events.
• Event data stored as binary-formatted files, hourly on controller.
• Controller storage allows for > 24 hours of raw data.
• Data uploaded via scheduled FTP and uncompressed into SQL database.
Byte # N Byte # N+1 Byte #’s N+2,N+3Event Type Assignment TimeStamp .0 = Begin Phase Off (1-16) Phase #1-16 Deciseconds past hour (0-35999)1 = Begin Phase Green (1-16) Phase #1-16 Deciseconds past hour (0-35999)2 = Begin Phase Yellow (1-16) Phase #1-16 Deciseconds past hour (0-35999)3 = Begin Phase Red Clear (1-16) Phase #1-16 Deciseconds past hour (0-35999)4 = Begin Ped Off (1-16) Phase #1-16 Deciseconds past hour (0-35999)5 = Begin Ped Walk (1-16) Phase #1-16 Deciseconds past hour (0-35999)6 = Begin Ped Clear (1-16) Phase #1-16 Deciseconds past hour (0-35999)7 = Reserved (Ped State) (1-16) Phase #1-16 Deciseconds past hour (0-35999)8 = Detector Transition Off (1-64) Detector #1-64 Deciseconds past hour (0-35999)9 = Detector Transition On (1-64) Detector #1-64 Deciseconds past hour (0-35999)10 = Detector RFU (1-64) Detector #1-64 Deciseconds past hour (0-35999)11 = Detector RFU (1-64) Detector #1-64 Deciseconds past hour (0-35999)12 = Begin Overlap Off (1-16) Overlap #A-P Deciseconds past hour (0-35999)13 = Begin Overlap Green (1-16) Overlap #A-P Deciseconds past hour (0-35999)14 = Begin Ovl Grn Extension (1-16) Overlap #A-P Deciseconds past hour (0-35999)15 = Begin Overlap Yellow (1-16) Overlap #A-P Deciseconds past hour (0-35999)16 = Begin Overlap Red Clr (1-16) Overlap #A-P Deciseconds past hour (0-35999)20 = Begin Preemptor (1-10) Preemption #1-10 Deciseconds past hour (0-35999)21 = End Preemptor (1-10) Preemption #1-10 Deciseconds past hour (0-35999)24 = Phase Hold Applied (1-16) Phase #1-16 Deciseconds past hour (0-35999)25 = Phase Hold Released (1-16) Phase #1-16 Deciseconds past hour (0-35999)26 = Ped Call on Phase (1-16) Phase #1-16 Deciseconds past hour (0-35999)27 = Ped Call Cleared (1-16) Phase #1-16 Deciseconds past hour (0-35999)28-31 = Phase Control RFU (1-16) Phase #1-16 Deciseconds past hour (0-35999)32 = Phase Min Complete (1-16) Phase #1-16 Deciseconds past hour (0-35999)33 = Phase Term Gap Out (1-16) Phase #1-16 Deciseconds past hour (0-35999)34 = Phase Term Max Out (1-16) Phase #1-16 Deciseconds past hour (0-35999)35 = Phase Term Force Off (1-16) Phase #1-16 Deciseconds past hour (0-35999)36-39 = Phase State RFU (1-16) Phase #1-16 Deciseconds past hour (0-35999)40 = Coord Pattern Change (0-253,Free,Flash) Deciseconds past hour (0-35999)41 = Cycle Length Change (0-255,seconds) Deciseconds past hour (0-35999)42 = Offset Length Change (0-255,seconds) Deciseconds past hour (0-35999)43-59 = Split (1-16) Change (0-255) Split Value Deciseconds past hour (0-35999)60-62 = Coord Data RFU (0-255) Deciseconds past hour (0-35999)
Elkhart County(local agency)
West Lafayette
(Pedestrians)
McCordsville(Railroad
pmt)
Noblesville(Corridor Performance
Measures)
Research Opportunities
Research Direction• Research intent is to define a set of signalized
intersection operating parameters that may reveal inefficiencies in cycle, offset and/or split timing.
• Identification of inefficiencies will help agencies focus retiming efforts on those intersections with the most observed need.
• INDOT and Industry intent to is to generalize these parameters such that commercialized systems can provide traffic engineers with a common toolset.
• Project focus upon measurement and reporting of performance data.
• Control level changes at intersection not addressed within the scope of project.
4 Int. Indianapolis Arterial
Indianapolis RR Preempt
West Lafayette Ped Int.
2 Int. in ElkhartCounty
~ 160 mil.
Events in SQL DB
DATA
Volume INFORMATION24 Flow Rates by phase/by cycle
P1 P2 P3 P4
P6 P5 P7 P81500
0
750
0:00 24:0012:00 0:00 24:0012:00 0:00 24:0012:00 0:00 24:0012:00
1500
0
750
Time of Day
Equ
iva
lent
Hou
rly F
low
Rat
e (
veh
/h)
Capacity INFORMATION
P1 P2 P3 P4
P6 P5 P7 P81.0
0.0
0.5
0:00 24:0012:00 0:00 24:0012:00 0:00 24:0012:00 0:00 24:0012:00
1.0
0.0
0.5
Time of Day
Vol
ume-
to-C
apac
ity R
atio
V/C Ratios by Phase, 24 Hours
Progression INFORMATION
Interim Accomplishments• Expansion and consistency of traffic controller
raw data logging format. – Presented as CSV format at system level, controller
encoding remains proprietary. – PEEK and Econolite have currently provided this CSV
interface.– Interim format used by partner vendors for research
interoperability.• Development of recommendations for
performance based data aggregation and metric logging within controller. – NTCIP 1202 object definitions are an anticipated output
from this effort.– Reuse of ACS-Lite status objects as log file being
considered.
Research Toolset• Econolite has supported research through
integration of research tools into Centracs system:
INDOT /Purdue Instrumented
Intersections (2003)Evolution of Researchto Product
~2009Automated SQL Ingestion and Purdue Parameterized
Excel Sheets
Product EnhancementsDifference between what has been developed as research tools for the various corridor studies to date with a generally applicable toolset that can be used daily by the practicing traffic engineer.
Econolite has started software development in both Centracs and the ASC/3 controller to generalize the results of the research to date into core product enhancements.
“Productization” Requirements:• Aggregation of raw controller events into a cycle-
cycle logging of arrival distributions using ACS Lite data objects.– Aggregation reduces data storage/bandwidth
requirements to allow broad deployment.• Periodic upload of arrival distribution log into
Centracs SQL database.– Supports query of current datasets and historic trends
across filterable displays and reports.• Centracs generation of graphical tools that
present this data as information in a manner usable by traffic engineers to make retiming decisions.– Enhanced PCD, Split analysis (V/C), Plan Performance
graphs.
Concluding Observations• This research has been a successful collaboration
of academia, agency, and vendors to standardize conceptual performance measures that assess the need for COS timing adjustments.
• Vendors are taking results and enhancing controller and system software to support the performance measurements and informational displays developed.
• Collaborative project efforts expected to continue for at least an additional year with definition of further performance measures.
• Vendors carry forward the goal for systems to automatically determine the degradation of performance and suggest remedial action to traffic engineers.
Contact Information:
Gary Duncan [email protected]
Eric [email protected]
Reference:Smaglik E.J., A. Sharma, D.M. Bullock, J.R. Sturdevant, and G. Duncan, “Event-Based Data Collection for Generating Actuated Controller Performance Measures," Transportation Research Record, #2035, TRB, National Research Council, Washington, DC, pp.97-106, 2007.Brennan, T.M., C.M. Day, J.R. Sturdevant, E. Raamot, and D.M. Bullock, “Railroad Preempted Intersection Track Clearance Performance Measures,” Transportation Research Board Paper ID:10-0118, in press.
Elkhart County(local agency)
West Lafayette
(Pedestrians)
McCordsville(Railroad
pmt)
Noblesville(Corridor Performance
Measures)
Research Opportunities