by Jon Meusch, PE and Mark Rodgers

When developing timing for traffic controllers we often wish the intersection itself could tell us which settings are working well and which are not.  Northwest Signal Supply (NWS) has programmed powerful data collection tools into its Voyage ATC software and M1 NEMA controller that log specific measurement data about an intersection’s operational effectiveness, or Measures of Effectiveness (MOE). Northwest Signal Supply’s MOEs provide time-stamped performance information for actuated and coordinated signal operation. 

In practice, timing optimization is an iterative process involving data collection, analysis, timing modification, and more data collection for verification.  Accurate observations of “what is” are essential to effective optimizations.  Voyage / M1 capture MOE data as a background operation while the controller operates according to its current timing parameters.  With no knowledge of this data collection, the controller is basically doing what it has been programmed to do.  Surprisingly, routine operation produces large volumes of data that must be stored until the user downloads it.  To help manage memory usage, MOE logging can be turned on or off so only data for specific operation periods is captured.  Analysis performed using the downloaded data helps determine which performance measures associate with which timing parameters. 

For an actuated signal running in FREE, Voyage / M1 MOE logs provide information about:

• How many times a vehicle phase was serviced in the sample period
• How many times a pedestrian phase was serviced in the sample period
• Average length of green time by phase
• Phase termination type: (Gap Out (desired), Max Out, Force-Off)

For an actuated signal running in Coordination, Voyage /  M1 log data might include:

• Cycle length and coordination plan in effect
• Split utilization by phase
• Percent of vehicles arriving during phase green time (vs. arriving during non-green time)
• Vehicle Arrival Type by phase

MOE data for a FREE running signal can help determine if the phases being recalled are appropriate for a specific part of the day.  Consider this example in which the north-south approaches of an intersection are heavier during the AM peak, yet during the PM peak the east-west approaches are heavier.  Typical signal timing assigns recalls to two mainline phases and never changes.  Altering the recall phases assures control will return to the high demand phases as soon as all other phases terminate.  If the approaches are balanced in demand, consider using soft-recall or a no-recall mode.

If an intersection has significant pedestrian crossing usage, Voyage / M1 provide a number of features that provide enhanced service and safety to pedestrians. Conditional Ped, for example, is a function that provides for late and multiple services to pedestrians.

When an intersection is congested the MOE log is marked by patterns of Max Outs or Force-Offs occurring in both rings and both sides of the barrier.  Creating a solution for congestion is a two step process.  The first step is to constrain the cycle time, which for a FREE running signal is the sum of phase max times for the longer ring.  The resulting virtual cycle time accounts for total waiting time per phase and provides a framework for distributing cycle time.  The second step is to determine the amount of green time that will allow each phase to Gap Out while enabling all phases to fit into the virtual cycle time.  Voyage / M1 provide a number of gap management features that provide more efficient gap termination, including gap reduction and lane-by-lane gap out.

If the intersection is NOT congested, Voyage / M1 can adjust Max Time using: TOD Max Plans or Auto-Max which dynamically increases / decreases Max Times based on cycle-by-cycle volume fluctuations in each phase.

During SYSTEM operation MOE data helps determine if Lead-Lag adjustments can help by moving phases that usually gap out to the lead phase position.  Cycle time surrendered by the gap-terminated phase can be used by subsequent phases, helping to reduce some force-off terminations.  If analysis of the splits shows that each phase has sufficient time to gap out, the splits may be reapportioned for greater efficiency.

In coordination, the system performs best when a well-defined platoon of vehicles moves without delay through the entire corridor.  Two measures help to determine the volume of traffic that arrives on green and how well the platoon boundaries are defined.  Percent arrival on green indicates how accurately the offset is set for the current operation.  In many cases, offset is a compromise of bi-directional progression objectives, yet some fine tuning is still practical.  Arrival Type [1] is a statistical score related to the quality of the platoon.  At the lower boundary score of one (1), arrivals are completely random and lack predictability.  As arrivals become more cohesive and defined the scores approach the upper limit of six (6).  Combined with other system measures, Arrival Type is useful for determining progressions relative to other signals surrounding the data source location.

Voyage 2070 and ATC software and the M1 NEMA controller are products of Northwest Signal Supply.  Both product families provide extensive logging capabilities that help traffic operations engineers measure timing effects and make meaningful positive adjustments.  Learn more about MOEs and the ways that Voyage / M1 can help enhance your traffic signal operations and maintenance at NWSignal.com or call our support staff at:  503-635-4351 (Mon-Fri 8am-5pm Pacific Time).

Bibliography:

   [1]  ASCE Journal of Transportation Engineering, July 2007, Vol. 133, No. 7, pp 415-422, “A Pilot Study on Real-Time Calculation of Arrival Type for Assessment of Arterial Performance”, Smaglik, E; E.M.Bullock; A. Sharma

Maston Wolfe, our company’s leader from its first day and former military engineer, envisioned building a ruggedly robust controller with upgradeable components and tactically powerful firmware.  M1 is his brainchild and proudly, our legacy to the industry he loved so much.

M1’s firmware supports full-spectrum timing controls including: phase functions & timing, coordination including our adaptive control algorithm, flexible preemption programming, TSP and a powerful user-logic programming language built in.  D-connectors are interchangeable to match several cabinet types.  Input and Output function assignments are easily changed.  M1 simplifies data communications by supporting multiple protocols and media, simultaneously.  M1 natively integrates with 2070 controllers operating NWS Voyage software supporting multi-agency coordinated systems.  M1’s quality is matched only by NW Signal’s generous and accessible engineering and technical support.  Contact us to learn more and check out one of our M1 demo units!

WYDOT has a significant investment in existing 2070 controllers. Moving to Voyage is a simple matter of replacing the firmware in these industry standard controllers. Northwest Signal Supply looks forward to serving the great State of Wyoming through our distributor, Western Signal.

Posted by NW Signal

The poles received a customized finish consisting of a dark “Railroad Green” paint applied using a powder coating process. Underneath the paint is a hot-dipped galvanized coating, guaranteeing a long life for these important structures.

We have them in stock along with nearly every other Astro-Brac combination.  All available for immediate shipping or just stop by and pick one up!  Northwest Signal Supply is the largest signal warehouse in the Pacific Northwest and the only Pelco distributor in Oregon.

Stop by or give us a call for help finding Pelco equipment or any other traffic related product.  Chances are we have it in stock!

Pelco Products, Inc. “Helping Hand”   P/N:  AB-0504 www.pelcoinc.com

http://www.pelcoinc.com/Portals/0/docs/pdfs/HelpingHand.pdf

Posted by NW Signal

Day 1 (Focus on Maintenance and General Knowledge)

Session 1
·         Quick overview of the morning (Ryan)
·         Controller Hardware Overview (Mark Rodgers)

Session 2: Hands on with Controllers
·         Using the Datakey (Dan)
·         Utilities, restart to incorporate changes, default data load (Dan)
·         Procedure review for controller swap out (Ryan)
·         Swap out a 170 and replace with a 2070 (Ryan)
·         Set up communications (Dan)
·         Interconnect details between cabinets (Dan)

Session 3: Hands on with Cabinets
·         Break up into teams, give out worksheet and have teams work together
·         Quick overview of Mark’s Introduction to Voyage document ( Mark)

Day 2 (Focus on Operations)

Session 4: Advanced Features (Jon)

Session 5: Wapiti Conversions (Ryan)

Session 6: Load converted Wapiti to Voyage database in controller (Ryan)

Quiz: Based on training content, get the right answers and win a prize (Dan)

Posted by NW Signal

ODOT provided $586,000 for the $7.17 million project, which will install new 2070 controllers and Voyage software at 21 intersections on 99W in Tigard between Interstate 5 and Southwest Durham Road. The project will use lower-cost signal control software to improve congestion along 99W.

Washington County also received $480,000 from ODOT to install a $7.65 million adaptive signal control on Tualatin-Sherwood Road, a key connection between 99W and I-5.

Read more

Posted by Jon Meusch

Northwest Signal Supply (NWS) manufactured 22 ITS cabinets for three separate construction contracts. The cabinet assemblies consisted of a 332 cabinet (made by NWS), power and communication/control panels, and battery back-up equipment. NWS integrated and tested the equipment to Wyoming DOT specifications.

Installation of the ITS cabinets was performed by Modern Electric, an established and respected electrical contractor in the State of Wyoming.

Posted by Rod Forrester

Northwest Signal Supply (NWS) had a large role as a vendor for this important project. Among the components that we manufactured and supplied were decorative aluminum housings for the vehicle signals, pedestrian signals and signs. Over $600,000 US worth of housings were sold.

An important design detail of the housings was that they had to accommodate normal mounting hardware used in the signal industry. For example, the pedestrian signals were required to mount to poles using standard “clam shells” and the housings had to be removable without interrupting the operation of the signals. Our engineering staff worked closely with architects to satisfy these functional requirements while at the same time creating the right “look”.

NWS also produced all of the catenary poles and traffic signal poles for the project. Our Voyage 2070 software was selected for the complex task of controlling light rail trains, motor vehicles and pedestrians at the signalized intersections. The installation of all of this equipment was performed by Tice Electric, a leading electrical contractor in the City of Portland.

Posted by Brian Morton

The AISC certification process verified that our organizational structure and manufacturing processes are appropriate to guarantee high quality products. The AISC team reviewed NWSs’ training practices, our welding procedures, our fabrication methods, our documentation and our record keeping. Further, they sent a welding expert to our plant to review our shop layout and equipment and to observe our fabricators at work. The end result is the achievement of a credential that we are well qualified to hold.

The requirement for AISC certification is becoming commonplace in the Standard Specifications for Departments of Transportation. California requires this certification of their pole manufacturers.

Posted by Daniel Emslie