City of Mesa ITS Traffic Signal Light Rail EOS Operation

Presented by City of Mesa, ITS Analyst - Steve Hall

Phoenix Light Rail Project 2005 - 2008

• 20-mile starter line in Phoenix, Tempe & Mesa
• 4 ints. in Mesa – three modified and one new
• Econolite ASC3 controllers with 2070 modules, equipped with NextPhase software
• Controllers/software unable to communicate to our traffic control system, because of AB3418
• Mesa using ICONs, which used only NTCIP
• These four operate off a single laptop
• Peer-to-Peer communication was done via web-relays

Dobson

Original NextPhase LRT Phasing

2008 – 2011

Central Mesa Extension (CME) Light Rail Project 2012-2015

• Almost 3 miles of LRT added to Mesa’s existing alignment. 12 intersections & 7 pedestrian crosswalks – 6 were new
• We upgraded ICONS to Centracs before this project
• The key elements to the operation of these 19 intersections were as follows; left-turn swapping, transit phase extension, transit phase insertion, and reverse running.
• ASC/3 controllers were used with an extensive number of logic statements (50) to enable the LRT operation. 2070 module no longer required for Centracs operation.
• Communication among these 19 intersections was handled via peer-to-peer on web relays, not in the controllers
• Converted the first four LRT intersections to Centracs

Alma School

Country Club

Mesa Dr.

CME Phase & Overlap assignments for our ASC3 Controllers

OVL D

6

TRAIN

TRAIN

OVL C

8

4

OVL E

OVL F

7

3

(OVL B)

(OVL A)

N

Mesa ITS Controller/Software Conversion

• In 2015 – 2016, Mesa ITS chose to change our controller operation of LRT alignment from ASC3 to McCain/D4
• More efficiently operate both vehicle & LRT phases together, the TSP/LRT/Transit functionality is incorporated into the general controller operation
• Unlike the ASC3 controllers, the controllers did not require logic statements to provide the functionality for LRT operations, except for reverse running aspect
• The biggest & best reason for switching to the new equipment was that the TSP/LRT/Transit functionality ran in the background of the intersection operation; it piggybacked on it, which allowed coordination patterns to deal directly with phase timing needs per the intersection. It gave us back the flexibility to adjust as needed.
• TSP/LRT/Transit functionality had its own settings, timing, and detections, but no new hardware other than the controller.
• Also, Peer-to-Peer functionality was available in these controllers with the TSP/LRT/Transit settings. The ASC3 had limited Peer-to-Peer functionality at that time.
• Late in 2016, we rolled these controllers out to our existing alignment of 23 intersections.
• Almost immediately, we had operational issue. Controller locked up in the vehicle & parallel LRT movement, only a preempt call in the perpendicular direction solved the issue without rebooting the controller. We created a logic statement work around while the software developers continued to research it.

Base Phase assignments for our McCain/D4 Controllers

6

6

TRAIN

TRAIN

2

8

4

1

5

7

3

(T6)

(T2)

N

Gilbert Road Extension (GRE) Light Rail Project 2016-2019

• This project added almost 2 miles of LRT to Mesa’s existing alignment. It modified 11 intersections to LRT configuration, adding 5 new and converting an existing to a roundabout.
• Mesa had already converted the existing 23 intersections to McCain controllers operating with D4 software before this project began.
• Mesa worked closely with the project consultants on this extension to incorporate the new intersections into the McCain/D4 operation. This project included FYA and a several offset-crosswalk intersections
• All of cabinets at these intersection were installed as Automated Traffic Control (ATC) cabinets.

Stapley

Gilbert

Horne

Mesa McCain/D4 Controller/Software Lab Testing

Primary Vehicle Ring Structure for our LRT Intersections

8 – Phase Arterial/Arterial

6 – Phase Arterial/Collector

3 – Phase Arterial/Ped Crossing

East/West Left Turns are Overlaps and can serve twice per cycle depending on demand.

The TSP/LRT/Transit configuration runs in the background while the vehicular/pedestrian ring structure is functioning.

The LRT phases will run during the vehicular phases 2 & 6, and left turn phasing can be swapped for an approaching LR vehicle.

A new offset crosswalk crossing with four phases

• Transit detection for WB is Check-In #13 and Check-Out #14.
• Transit detection for EB is Check-In #15 and Check-Out #16.
• Reverse running is configured in the logic statements looking for detections in the opposite direction, like Check-in #14 then Check-Out #13. This may occur due to accidents or for the final loading station.

Mesa TSP/LRT/Transit Detection

Peer-to-Peer Communication Example

CHECK-IN DETECTOR

CHECK-OUT DETECTOR

• Mesa uses the Check-Out detector to send a Peer call to the next downstream intersection(s), based on travel time and dwell time, to begin TSP.
• If TSP times out prior to arrival, then the local intersection Check-In will re-enable the TSP operation upon detection.
• If the Check-out detection fails, TSP will continue to receive a peer call.

Is the EOS a possibility?

• D4 had an operation issue.
• June 2020, developing EOS LRT operation
• Mesa long working relationship with Econolite
• EOS software was the Econolite answer to the fully programmable controller, including multi-intersection control, TSP/SCP and Hybrid.
• Knew our D4 configuration;
• Maintain consistency as much as possible
• Can we do this w/o rewiring each cabinet & intersection (34)?
• Place the EOS controller directly into our cabinet
• Can we monitor Transit status items in Centracs?
• 2024, multiple controller software versions & Centracs updates, we were comfortable with the programming in the EOS software … Yes
• So, Let’ see our TSP/SCP programming….

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EOS LRT Configuration Programming

• Load Switch Configuration – Channels 13 & 14 are assigned “V” for channel type and their respective number for phases 13 & 14.
• Cabinet Mapping;
• (NEMA Cabinet) TF BIU 2 – used appropriate Phase 13 & 14 yellows for the SCP Adv Warning respectively.
• (ATC Cabinet) SIU 1 Output - Phase 13 & 14 yellows for the SCP Adv Warning respectively.
• Communications; Peer to Peer Setup – Peers 1-4 assigned to east of Peers 5-8 assigned to west
• Peer 1 assigned to 1st int. to the east (Controller IP entered)
• Peer 2 assigned to the 2nd int. to the east
• Peer 3 & 4 to the 3rd & 4^th ints to the east respectively
• Peer 5 assigned to the 1st int to the west,
• Peer 6 assigned to the 2nd int to the west,
• Peer 7 & 8 to the 3^rd & 4^th ints to the west respectively

​

Mesa EOS LRT Programming Scheme

EOS LRT Configuration Programming (cont.)�Peer to Peer Logic Statements

• Logic Statement #1; Example
• If: Peer (1) T/F (T) Assignment (LP CIB CODE ON) State (509)
• Then: Assignment (LP SET CIB ON) # (314)
• Logic Statement #2, 3 and 4 are configured in all controllers.
• Logic Statement #5; Example
• If: Peer (5) T/F (T) Assignment (LP CIB CODE ON) State (511)
• Then: Assignment (LP SET CIB ON) # 318
• Logic Statement #6, 7 and 8 are configured in all controllers.
• Then they are enabled as needed.
• Also, Logic Statements #13 thru #16 are being used to convert the vehicle detection channels 13-16, respectively, to enable the TSP/SCP operation by CIB Codes 509 (WB) & 511 (EB) for the transit check-in and check-out.

EOS Controller Programming

• Sequence#1; the primary sequence that used almost every cycle.
• Sequence #2; the sequence to be used when the controller needs to swap phases around to allow the transit vehicle to move through the intersection as efficiently as possible.
• Sequence No Serve; the phases that we do “NOT” want serving when the SCP phases are active.
• Timing Plan; Phases 13 & 14 are programmed with minimum green values (15 secs), and the transit clearance values (13.0 secs).
• Timing Plan; Phase Recall – Phases 13 & 14 have a soft recall on them for extending.
• Options; Phases 13 & 14 are enabled for LRT/BRT Phase and 2 Section Signal.

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EOS LRT Preempt Programming�TSP/SCP Plan and Split (tab)

1. Most Aggressive

1-3 EVP & 4-10 SCP

10. Least Aggressive

SCP Det 1 = CIB Code On 314

SCP Det 2 = CIB Code On 315

SCP Det 3 = CIB Code On 316

SCP Det 4 = CIB Code On 317

SCP Det 5 = CIB Code On 318

SCP Det 6 = CIB Code On 319

SCP Det 7 = CIB Code On 268

SCP Det 8 = CIB Code On 269

EOS LRT Detector Configuration

• Vehicle Detector;
• Channel 13; Phase 13 and the Called Phase is 13.
• Channel 14; Phase 13 and the Called Phase is 13.
• Channel 15; Phase 14 and the Called Phase is 14.
• Channel 16; Phase 14 and the Called Phase is 14.
• Vehicle Detector Setup
• Vehicle Detector 13-16; Call Option is set to “Call”.

Additional Prep

• Created a “mock” three intersection configuration
• Tested Logic Statements & Peer to Peer configuration and revised
• Created all 34 LRT intersection databases
• Downloaded each database into a test controller, let them operate for 48 hours and labeled them
• February 2025. install over a couple of weeks during our MMU PM period
• Started at East end (end of the line) and worked West towards Tempe, started with four at the end on the line
• Technicians handled the controller changeout and the MMU work at the intersection
• I was on-site verifying operation after change-out and addressing any questions
• Our other Analyst, was in the office, handling the Centracs programming changes per intersection responsibilities
• Two police officers each of the days for traffic control during the changeouts
• Time to observe and adjust, as necessary.

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Observation Issues or Revisions

• D4 operated both LRT phases together, EOS operates them by direction, created new logic statements to activate the opposing LRT direction.
• Class Type was not operating as anticipated, adjusted to more aggressive setting.
• All of our EOS LRT controllers are constantly in “transition”, very rarely in coordination.
• In the database editor, the Ring Split Sum is not functioning correctly.
• Stakeholders have noticed some traffic signal operational changes beyond expections and have questioned it.
• Work with Valley Metro to provide a better understanding of the overall operation.
• The controller is only showing the first P2P SCP detector to communicate & it’s ETA. If, a second SCP detector is enabled, only the ETA is updated. If, a delay occurs before reaching the intersection of interest, the first P2P SCP detector probably will time out. LRT will have to re-initialize the SCP operation on the local detector.

EOS Front Panel View�SCP Status - Operating

Questions ?

Steve Hall

City of Mesa ITS Analyst

steven.hall@mesaaz.gov