Module 31 - A315a

A315a: Understanding User Needs for Actuated Traffic Signal Controllers (ASC) Based on NTCIP 1202 Standard

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Slide 1:

Welcome - Graphic image of introductory slide. Please see the Extended Text Description below.

(Extended Text Description: Slide 1: Welcome - Graphic image of introductory slide. A large dark blue rectangle with a wide, light grid pattern at the top half and bands of dark and lighter blue bands below. There is a white square ITS logo box with words "Standards ITS Training" in green and blue on the middle left side. The word "Welcome" in white is to the right of the logo. Under the logo box are the words "RITA Intelligent Transportation Systems Joint Program Office.")

 

Slide 2:

Welcome

Head shot photo of Ken Leonard, Director - ITS Joint Program Office

Ken Leonard, Director

ITS Joint Program Office

Ken.Leonard@dot.gov

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(Extended Text Description: Intro Slide: Screen capture snapshot of RITA website - for illustration only. Below this image is a link to the current website: http://www.pcb.its.dot.gov - this screen capture snapshot shows an example from the RITA website from April 2013. At the top of the page it shows the RITA logo with the text U.S. Department of Transportation Research and Innovative Technology Administration - Intelligent Transportation Systems Joint Program Office - ITS Professional Capacity Building Program/Advanced ITS Education. Below the main site banner, it shows the main navigation menu with the following items: About, ITS Training, Knowledge Exchange, Technology Transfer, ITS in Academics, and Media Library. Below the main navigation menu, the page shows various content of the website, including a graphic image of professionals seated in a room during a training program. A text overlay has the text Welcome to ITS Professional Capacity Building. Additional content on the page includes a box entitled What's New and sections entitled Available E-Training (free), Free ITS Training and T3 Webinars. Again, this image serves for illustration only. The current website link is: http://www.pcb.its.dot.gov)

www.pcb.its.dot.gov

(Note: There is additional text attached to this slide that includes the following introductory information from Ken Leonard):

"ITS Standards can make your life easier. Your procurements will go more smoothly and you'll encourage competition, but only if you know how to write them into your specifications and test them. This module is one in a series that covers practical applications for acquiring and testing standards-based ITS systems.

I am Ken Leonard, director of the ITS Joint Program Office for USDOT and I want to welcome you to our newly redesigned ITS standards training program of which this module is a part. We are pleased to be working with our partner, the Institute of Transportation Engineers, to deliver this new approach to training that combines web based modules with instructor interaction to bring the latest in ITS learning to busy professionals like yourself.

This combined approach allows interested professionals to schedule training at your convenience, without the need to travel. After you complete this training, we hope that you will tell colleagues and customers about the latest ITS standards and encourage them to take advantage of the archived version of the webinars.

ITS Standards training is one of the first offerings of our updated Professional Capacity Training Program. Through the PCB program we prepare professionals to adopt proven and emerging ITS technologies that will make surface transportation safer, smarter and greener which improves livability for us all. You can find information on additional modules and training programs on our web site www.pcb.its.dot.gov

Please help us make even more improvements to our training modules through the evaluation process. We look forward to hearing your comments. Thank you again for participating and we hope you find this module helpful."

 

Slide 3:

Activity. A placeholder graphic with an image of hand over a computer keyboard to show that an activity is taking place.

 

Slide 4:

A315a:

Understanding User Needs for Actuated Traffic Signal Controllers (ASC) Based on NTCIP 1202 Standard

 

Slide 5:

Instructor

Headshot photo of Kenneth L. Vaughn, P.E., President, Trevilon Corporation Magnolia, TX, USA

Kenneth L. Vaughn, P.E.

President

Trevilon Corporation

Magnolia, TX, USA

 

Slide 6:

Target Audience

  • Traffic management and engineering staff
  • TMC/operations staff
  • Traffic signal maintenance staff
  • System developers
  • Private and public sector users including manufacturers

 

Slide 7:

Recommended Prerequisites

  • I101: Using ITS Standards: An Overview
  • A101: Introduction to Acquiring Standards-based ITS Systems
  • A102: Introduction to User Needs Identification
  • A201: Details On Acquiring Standards-based ITS Systems
  • A202: Identifying and Writing User Needs When ITS Standards Do Not Have SEP Content
  • A103: Introduction to ITS Standards Requirements Development
  • A203: Writing Requirements When ITS Standards Do Not Have SEP Content

 

Slide 8:

Recommended Prerequisites Cont.

  • C101: Introduction to the Communications Protocols and Their Uses in ITS Applications
  • Basic Understanding of Advanced Transportation Controller (ATC) Standards Family, if ATCs are to be used
  • Knowledge of American-style traffic signal operations
  • Basic Understanding of NEMA Technical Standard (TS) 2

 

Slide 9:

Curriculum Path (Non-SEP)

A graphical illustration indicating the sequence of training modules that lead up to and follow this course. Please see the Extended Text Description below.

(Extended Text Description: A graphical illustration indicating the sequence of training modules that lead up to and follow this course. Each module is represented by a box with the name of the module in it and an arrow showing the logical flow of the modules and the current module highlighted. This slide focuses on the modules that lead up to the current course. The first box is labeled "I101 Using ITS Standards: An Overview." An arrow from this box connects it to a box labeled "A101 Introduction to Acquiring Standards-based ITS Systems." An arrow from this box connects it to a box labeled "A102 Introduction to User Needs Identification." An arrow from this box connects it to a box labeled "A201 Details on Acquiring Standards-based ITS Systems." An arrow from this box connects it to a box located at the start of the next line and labeled "A202 Identifying and Writing User Needs When ITS Standards Do Not Have SEP Content." An arrow from this box connects it to a box labeled "A103 Introduction to ITS Standards Requirements Development." An arrow from this box connects it to a box labeled "A203 Writing Requirements When ITS Standards Do Not Have SEP Content." An arrow from this box connects it to a box labeled "C101 Intro. To Comm. Protocols and Their Use in ITS Applications." An arrow from this box connects it to a highlighted box designating this module, which is located at the start of the next line and labeled "A315a Understanding User Needs for ASC Based on NTCIP 1202 Standard." An arrow from this box connects it to a grayed out box, which represents the next course, labeled "A315b Specifying Requirements for ASC Based on NTCIP 1202 Standard.")

 

Slide 10:

Learning Objectives

  1. Review the structure of the NTCIP 1202 ASC v02 Standard
  2. Evaluate ASC-specific operational needs
  3. Identify and write user needs for ASC
  4. Appreciate trade-offs between stakeholder desires versus realistic requirements
  5. Briefly explain how to evaluate conformance to the ASC standard
  6. Introduce the relationship of needs to requirements and conformance

 

Slide 11:

Learning Objective #1—Review the Structure of NTCIP 1202 v02

  • Be able to identify the ASC standard in the NTCIP Framework
  • Understand content of the standard
  • Understand the relationship between NEMA TS2 and NTCIP 1202

 

Slide 12:

Learning Objective #1

NTCIP Family

A graphic of the communication levels of the NTCIP standards. Please see the Extended Text Description below.

(Extended Text Description: A graphic of the communication levels of the NTCIP standards. Author's relevant description: The bottom level is the Plant Level and includes boxes for Dial-up, Fiber, Coax, Wireless, Twisted Pair, and Leased Line. The next higher level is called the Subnetwork Level and includes PPP, Ethernet, and PMPP. The next level is called the Transport Level and includes TCP/IP, UDP/IP, and T2/NULL. The next level is called the Application Level and includes C2C XML, DATEX, FTP, TFTP, SNMP, and STMP. The next level is called the Information Level and includes C2C Messages, Files, Data Objects, and Dynamic Objects. These boxes are connected to an overarching box also in the Information Level labeled Functional Area Data Dictionaries with the left hand side identifying C2C Data Dictionaries and the right hand side labeled NTCIP Data Dictionaries. The NTCIP Data Dictionaries is highlighted with a circle indicating that it is the subject of the NTCIP 1201 and 1202 standards.)

Source: NTCIP 9001: NTCIP Guide

 

Slide 13:

Learning Objective #1

History of NTCIP 1202

  • Version 1: Approved in 1996 (Originally called TS3.5)
  • Amendment 1
    • Drafted in 1999 but content rolled into version 2
  • Version 2: Approved in 2005
    • Added block objects to make more bandwidth efficient

 

Slide 14:

Learning Objective #1

What is NTCIP 1202?

What does it contain?

  • Defines aspects of a communications interface standard
    • Between an Actuated Traffic Signal Controller (ASC) and its monitoring system (e.g., central or SSM)
  • Defines data elements (i.e., the vocabulary) used to monitor and control an ASC
    • References NTCIP 1201 for generic data elements
  • Supports functional requirements of NEMA TS2
    • NEMA TS2 standardizes the traditional functions of American traffic signal controllers

 

Slide 15:

Learning Objective #1

What is NTCIP 1202?

What is not included?

  • Explicit support for adaptive signal control logic
  • User needs
  • Functional requirements
  • Message dialogs
  • Test procedures

 

Slide 16:

Learning Objective #1

What is NTCIP 1202?

Complements ASC hardware and functional specifications and standards

This figure shows three overlapping circles related to What is NTCIP 1202? Please see the Extended Text Description below.

(Extended Text Description: This figure shows three overlapping circles. One is labeled "Hardware Specification: NEMA TS2, ATC5202 Mod 2070, ATC Controller, Caltrans 170, or NYDOT 179;" the next is labeled "Functional Specification: NEMA TS2 and/or Agency Specifications;" and the final one is labeled "Interface Specification: NTCIP 1201, NTCIP 1202, and Agency Specifications." The overlap symbolizes that each of these specifications are likely to cover topics that relate to other portions of the specifications and that care must be taken to avoid any conflict between these distinct sections of the overall procurement package.)

 

Slide 17:

Learning Objective #1

Understand the Structure of NTCIP 1202

  • Section 1: General
  • Section 2: Object Definitions
    • Data elements for field devices are called "objects"
    • Design elements for ASC functionality
  • Annex A: Information Profile
    • Groups objects according to logical functions
    • Defines conformance groups

 

Slide 18:

Learning Objective #1

Understand the Structure of NTCIP 1202

  • Annex B: Consistency Checks
    • Defines precise rules that must be followed when validating controller configuration
  • Annex C: Concept of Operations
    • Explains a set of design patterns used to exchange information
  • Annex D: Deprecated Objects
    • Old designs from previous versions of the standard

 

Slide 19:

Learning Objective #1

Advantages of NTCIP 1202

  • Provides common design elements and definitions
  • Defines common baseline of conformance
  • Defines specific set of consistency checks that must be performed
  • A step towards interoperability and interchangeability
    • NTCIP does not yet provide a complete solution
    • NTCIP does address some of the issues that must be overcome to integrate disparate systems

 

Slide 20:

Learning Objective #1

Relationship: NTCIP 1202 and NEMA TS2

Most NTCIP 1202 data elements reference NEMA TS2

  • NEMA TS2 standardized signal functionality in the U.S.
  • NTCIP supplements TS2 by defining data elements
    • Data elements are the individual pieces of data that are exchanged between the signal controller and the monitoring system
  • For example, NTCIP 1202 Clause 2.2.2.8 defines the "phaseYellowChange" data element and includes the following line:

REFERENCE "NEMA TS2 Clause 3.5.3.1 and 3.5.3.2.5.a"

 

Slide 21:

Learning Objective #1

Data Element Definitions

  • An instance of a "Data Element" can be called a "parameter."
  • NEMA TS2 Clause 3.5.3.2.5.a
    • "Following the Green interval of each phase the Controller Unit (CU) shall provide a Yellow Change interval which is timed according to the Yellow Change timing control for that phase."
  • NTCIP 1202 Clause 2.2.2.8
    • "Following the Green interval of each phase the CU shall provide a Yellow Change interval which is timed according to the Yellow Change parameter for that phase."

 

Slide 22:

Learning Objective #1

Range Definitions

  • NEMA TS2 Clause 3.5.3.1: Minimum Requirements
    • Function: Yellow Change
    • Minimum Range: 3-25.5 seconds
    • Maximum Increment: 0.1 second
  • NTCIP 1202 Clause 2.2.2.8
    • Parameter: phaseYellowChange
    • SYNTAX: INTEGER (0..255)
    • UNIT: tenth second

 

Slide 23:

Learning Objective #1

NTCIP 1202 Based on Accepted Standard

  • Does not contain user needs
  • Based on established standard (NEMA TS2) that defines core functionality

 

Slide 24:

Activity. A placeholder graphic with an image of hand over a computer keyboard to show that an activity is taking place.

 

Slide 25:

Learning Objective #1

Which item is not a part of NTCIP 1202?

Answer Choices

  1. Consistency checks
  2. Information profile
  3. User needs
  4. Object (data) definitions

 

Slide 26:

Learning Objective #1

Review of answers

A small graphical red and yellow X representing incorrect.a) Consistency checks
Incorrect; consistency checks are included in Annex B.

 

A small graphical red and yellow X representing incorrect.b) Information profile
Incorrect; an information profile is included in Annex A.

 

A small graphical green and yellow check mark representing correct.c) User needs
Correct; NTCIP 1202 does not contain any Systems Engineering content.

 

A small graphical red and yellow X representing incorrect.d) Object (data) definitions
Incorrect; object definitions are provided in Section 2.

 

Slide 27:

Summary of Learning Objective #1

Review the Structure of NTCIP 1202 v02

  • Defines the data elements for information exchange between signal controller and monitoring system
  • Based heavily on NEMA TS2
  • Complements all American signal controller hardware standards
  • Does not include Systems Engineering Process (SEP) content, such as user needs

 

Slide 28:

Learning Objective #2— Evaluate ASC-specific Operational Needs

  • Be able to evaluate your operational needs
  • Understand how ASC standard meets your operational and maintenance needs
  • Recognize how TS2 and 1202 are intertwined
  • Understand constraints which will impact cost-benefits
  • Be aware of issues that one can confront when preparing a procurement

 

Slide 29:

Learning Objective #2

Developing User Needs

  • Course A202: Identifying and Writing User Needs When ITS Standards Do Not Have SEP Content
    • Provides generic background on how to extract needs from non-SEP standards
    • We will apply this process to NTCIP 1202

 

Slide 30:

Learning Objective #2

Understand ASC Specific Operational Needs

  • Concept of Operations reveals the "big picture"
    • What is the current situation and problem?
    • Who are the users? Who is affected?
    • What are the operational scenarios?
    • What are the operational needs?
    • Are there any regional aspects?
  • NTCIP 1202 implicitly makes assumptions about these questions
  • Projects should explicitly address these issues in their own ConOps

 

Slide 31:

Learning Objective #2

Current Situation, Problem Statement

  • Agencies are responsible for managing the operation of the transportation network
  • Conflicting movements at intersections must be managed to prevent collisions
  • Some intersections need more than simple yield/stop sign control due to safety and/or efficiency reasons
  • Industry solution is to use a traffic signal controller sequentially grant right of way to specific movements

 

Slide 32:

Learning Objective #2

Current Situation, Problem Statement

  • Signals located near one another can impact each other's operations and should be coordinated
  • Agencies wish to manage signals remotely to reduce maintenance and operations costs
  • Prior to NTCIP, there was no industry standard for remote communications, only proprietary solutions

 

Slide 33:

Learning Objective #2

Reference Physical Architecture

A graphic representing a typical signalized intersection. Please see the Extended Text Description below.

(Extended Text Description: A graphic representing a typical signalized intersection. Author's relevant description: It includes four approaches to the intersection, which is controlled by a traffic signal. The signal head is connected to the signal controller hardware, which is connected to the control center. The intersection is highlighted by a circle labeled "Operational Logic" and is shown as being associated with NEMA TS 2. The signal control hardware is shown as being associated with NEMA TS 2, ATC, 170, 179, etc. Finally, the link between the Signal Controller Hardware and the Control Center is shown as being associated with NTCIP 1202.)

 

Slide 34:

Learning Objective #2

Steps to Writing a User Need

A slide showing the logical progression of the steps to writing a user need. Please see the Extended Text Description below.

(Extended Text Description: A slide showing the logical progression of the steps to writing a user need. Along the left-had side, the steps are labeled 'A' through 'D' and the main figure includes each step shown from the upper left to the lower right connected by arrows. The four steps are "Operational Needs," "ITS Standard," "Extraction Process," and "Writing Criteria.".)

 

Slide 35:

Learning Objective #2

How to Identify Operational Needs

  • Regional architecture
    • Are any specific functions assigned to the local controller?
  • Project description
    • Are there specific features being requested for signal control?
  • Operational scenarios
    • Work with stakeholders to discover how they want to operate and interact with the system under different scenarios

 

Slide 36:

Learning Objective #2

How to Identify Operational Needs

  • NEMA TS2 defines functionality for traffic signal controllers
    • Functional aspects of standard provides the logical model used by virtually all American controller deployments
  • NTCIP 1201 and NTCIP 1202
    • 1201 defines generic data and 1202 defines ASC-specific data
  • Case studies/industry experience
    • Work with other agencies that have deployed signal systems

 

Slide 37:

Learning Objective #2

How to Identify Operational Needs

A slide that indicates how the various sources of operational needs fit together by representing each source as an oval. Please see the Extended Text Description below.

(Extended Text Description: A slide that indicates how the various sources of operational needs fit together by representing each source as an oval. The "Regional Architecture" oval is very thin, is at the top of the slide and covers the width of the slide. The "Project Description" oval only covers a small amount of the width of the slide and overlaps the "Regional Architecture" oval in one area while going slightly deeper. The "Scenarios" oval is the same width as the "Project Description" oval, but is located lower with partial overlap. The "Standards" oval covers the entire width of the slide and covers the entire width and partially overlaps with "Scenarios." The "Case Studies" oval covers the entire width of the slide and overlaps with all of the previous ovals. Finally, the "ConOps" oval covers the width of the "Project Description" and overlaps with all of the other ovals and is at a medium vertical position.)

Not to scale

 

Slide 38:

Learning Objective #2

Pitfalls in Identifying Operational Needs

Failure to consider any source can lead to problems

  • Failure to consider project description can result in missing capabilities or specifying unnecessary features
  • Failure to consider architecture may impose functionality on device that will be performed elsewhere
  • Failure to consider scenarios may inadvertently ignore performance needs

This is largely true of SEP standards as well

 

Slide 39:

Learning Objective #2

Steps to Writing a User Need

A Operational Needs

  1. Desire to configure traffic signals from a remote management center using third-party software
  2. Desire to control traffic signals from a remote management center using third-party software
  3. Desire to monitor traffic signals from a remote management center using third-party software

 

Slide 40:

Learning Objective #2

Categories of Operational Needs

  • Configure
    • Maintenance desires a single ASC model that can be configured for any intersection
    • Management desires safety features to prevent remote reconfiguration of safety-critical information
  • Control
    • Operators desire to control the selection of timing patterns
  • Monitor
    • Operators desire to monitor real-time signal operations
    • Maintenance desires to monitor signal diagnostics to detect equipment failures

 

Slide 41:

Learning Objective #2

Benefit/Cost Considerations

Need to live within budget constraints

  • How many phases do you really need to support?
  • Are desired custom features justified by added cost to project?

NEMA TS2 provides a baseline of what industry typically supports

  • Number of phases, detectors, etc.
  • Which standardized features are mandatory

Interoperability requires significant agency specifications

 

Slide 42:

Activity. A placeholder graphic with an image of hand over a computer keyboard to show that an activity is taking place.

 

Slide 43:

Learning Objective #2

Which of the following can be used to discover operational needs?

Answer Choices

  1. Regional architecture
  2. Operational scenarios and stakeholder input
  3. ITS standards
  4. All of the above

 

Slide 44:

Learning Objective #2

Review of answers

A small graphical red and yellow X representing incorrect.a) Regional architecture
Incorrect; the architecture can identify high-level needs, but the other options are also useful.

 

A small graphical red and yellow X representing incorrect.b) Operational scenarios and stakeholder input
Incorrect; scenarios can identify mid-level needs, but the other options are also useful.

 

A small graphical red and yellow X representing incorrect.c) ITS standards
Incorrect; ITS standards can identify low-level needs, but the other options are also useful.

 

A small graphical green and yellow check mark representing correct.d) All of the above
Correct! All of these tools can be used to identify user needs.

 

Slide 45:

Summary of Learning Objective #2

Evaluate ASC-specific Operational Needs

  • Identifying operational needs is an important part of the ConOps process
  • Operational needs should be derived from a number of sources
  • Definition of operational needs will impact project costs
  • A baseline of widely supported features is defined in NEMA TS2

 

Slide 46:

Learning Objective #3—Identify and Write User Needs for ASC

  • Understand that standardized user needs do not exist for traffic signals
  • Understand how to extract and write needs for ASC procurement
  • Appreciate trade-offs between fulfilling desires of stakeholders versus setting realistic requirements

 

Slide 47:

Learning Objective #3

Learning to Identify and Write User Needs

  • User needs are not in NTCIP 1202
  • Agencies must develop them for the acquisition
    • Identify major desired capabilities from various sources
    • Compare to extracted capabilities from standard
    • Write user needs

 

Slide 48:

Learning Objective #3

Steps to Writing a User Need

A Operational Needs

  1. Desire to configure traffic signals from a remote management center using third-party software
  2. Desire to control traffic signals from a remote management center using third-party software
  3. Desire to monitor traffic signals from a remote management center using third-party software

From the original slide, this is an arrow pointing down and to the right to the line of text below which reads ITS Standard - NTCIP 1202 ASC

B ITS Standard

NTCIP 1202 ASC

 

Slide 49:

Learning Objective #3

NEMA TS2 and NTCIP 1202

  • NEMA TS2 is America's main standard for signal control logic
  • NTCIP 1202 based largely on NEMA TS2 logical concepts
  • NTCIP 1202 implements a few features not defined in NEMA TS2
    • Typically features used by non-NEMA controllers

 

Slide 50:

Learning Objective #3

Steps to Writing a User Need

B ITS Standard

NTCIP 1202 ASC

From the original slide, this is an arrow pointing down and to the right to the line of text below which reads Extraction Process

C Extraction Process

 

Slide 51:

Learning Objective #3

Simple Extraction

Some generic needs can be derived from NTCIP standards that contain SEP content, such as NTCIP 1203 for DMS

  • UN 1.1: Live Data Exchange (NTCIP 1203 Clause 2.4.2.1)
  • UN 1.2: Logged Data Exchange (NTCIP 1203 Clause 2.4.2.2)
  • UN 1.3: Support Legacy Communication Networks (NTCIP 1210 Clause 2.4.4)

When applicable, these are valuable since they are generally fully defined

 

Slide 52:

Learning Objective #3

Extract Capabilities from Conformance

Groups

A graphic representing the three major steps in extracting capabilities from conformance groups. Please see the Extended Text Description below.

(Extended Text Description: A graphic representing the three major steps in extracting capabilities from conformance groups. The left-hand box identifies the need to "read conformance groups" as the first step in the process. This box is connected by an arrow to the middle-box, which identifies the need to "recognize categories of functions." This box is connected to a final right-hand box that indicates the need to "infer major desired capability.".)

 

Slide 53:

Learning Objective #3

Conformance Group (CG)

  • A CG is a logical grouping of related objects
  • CGs help in determining required information to support a function
  • Example: Volume Occupancy Report CG
    • volumeOccupancySequence
    • volumeOccupancyPeriod
    • activeVolumeOccupancyDetectors
    • volumeOccupancyTable
      • detectorVolume
      • detectorOccupancy

 

Slide 54:

Learning Objective #3

Extract Capabilities: Read

From NTCIP 1202 Information Profile

Ref Areas Clause Status
A.3 Phase Conformance Group NTCIP 1202 - 2.2 M
A.4 Detector Conformance Group NTCIP 1202 - 2.3 M
A.5 Volume Occupancy Report Conformance Group NTCIP 1202 - 2.3 O
A.6 Unit Conformance Group NTCIP 1202 - 2.4 O
A.7 Special Function Conformance Group NTCIP 1202 - 2.4 O
A.8 Coordination Conformance Group NTCIP 1202 - 2.5 O
A.9 Time Base Conformance Group NTCIP 1202 - 2.6 O
A.10 Preempt Conformance Group NTCIP 1202 - 2.7 O
A.11 Ring Conformance Group NTCIP 1202 - 2.8 O
A.12 Channel Conformance Group NTCIP 1202 - 2.9 O
A.13 Overlap Conformance Group NTCIP 1202 - 2.10 O
A.14 TS 2 Port 1 Conformance Group NTCIP 1202 - 2.11 O
A.15 Block Object Conformance Group NTCIP 1202 - 2.12 O

Source: NTCIP 1202 v02 p. 135

 

Slide 55:

Learning Objective #3

Example: Extract Capabilities from Standard

  • Read: Phase Conformance Group
    • Includes phaseWalk, phaseMinimumGreen, phaseYellowChange, etc.
  • Recognize: Phase timing parameters
    • Maps to identified operational needs of configuring for any intersection and safety issues
  • Infer: Consider three major operational categories
    • Configure
    • Control
    • Monitor

 

Slide 56:

Learning Objective #3

Infer Major Desired Capability

  • Configure intersection timing parameters
    • May want to restrict some parameters for safety issues
  • Control intersection timing parameters
    • Not applicable
  • Monitor intersection timing parameters
    • Allows agency to determine current configuration

 

Slide 57:

Learning Objective #3

Example: Extract Capabilities from Standard

  • Read: Phase Conformance Group
    • maxPhases has a range of 2 to 255
  • Recognize: Two phases will not meet our needs; requiring 255 phases may increase costs
  • Infer: Need to determine and document how many phases we need

 

Slide 58:

Learning Objective #3

Example: Extract Capabilities from Standard

  • Read: Phase Conformance Group
    • phaseStatusGroupReds, phaseStatusGroupGreens, etc.
  • Recognize: Monitor current signal timing
    • Maps to identified operational need of monitoring realtime signal timing
  • Infer: Consider three major categories
    • Configure
    • Control
    • Monitor

 

Slide 59:

Learning Objective #3

Example: Extract Capabilities from Standard

  • Read: Phase Conformance Group
    • phaseControlGroupPhaseOmit, phaseControlGroupHold, etc.
  • Recognize: Remotely control detailed signal operations
    • Does not map to any identified operational need
    • Should verify with stakeholders that feature is not needed

 

Slide 60:

Learning Objective #3

Example: Extract Capabilities from Standard

  • Read: Coordination Conformance Group
    • coordOperationalMode, coordPatternStatus
  • Recognize: Ability to manually select timing pattern
    • Maps to desire to control selection of a timing pattern
  • Infer: Consider three major categories
    • Configure
    • Control
    • Monitor

 

Slide 61:

Learning Objective #3

Example: Extract Capabilities from Standard

  • Read: Detector Conformance Group
    • vehicleDetectorTable, maxVehicleDetectors, etc.
  • Recognize: Ability to configure detectors for the intersection
    • Maps to configuring for any intersection
  • Infer: Consider three major categories
    • Configure
    • Control
    • Monitor

 

Slide 62:

Learning Objective #3

Example: Extract Capabilities from Standard

  • Read: Detector Conformance Group
    • vehicleDetectorErraticCounts, vehicleDetectorAlarms, vehicleDetectorStatusGroupAlarms, etc.
  • Recognize: Ability to identify detector diagnostics
    • Maps to desire to monitor signal diagnostics
  • Infer: Consider three major categories
    • Configure
    • Control
    • Monitor

 

Slide 63:

Learning Objective #3

Example: Extract Capabilities from Standard

This slide shows the mapping between the major capabilities and the conformance groups that have been discussed during this presentation, with each item represented with a box. Please see the Extended Text Description below.

(Extended Text Description: This slide shows the mapping between the major capabilities and the conformance groups that have been discussed during this presentation, with each item represented with a box. The major capabilities are on the left and the conformance groups are on the right with lines connecting them. "Safely Configure Signal for Intersection Layout" is connected to "Phase Conformance Group" and "Detector Conformance Group." "Monitor Signal Configuration" is connected to "Phase Conformance Group" and "Detector Conformance Group." "Monitor Signal Timing" is connected to "Phase Conformance Group." "Control Selection of Timing Pattern" is connected to "Coordination Conformance Group." "Monitor Timing Pattern Selection" is connected to "Coordination Conformance Group." "Monitor Signal Diagnostics" is connected to "Detector Conformance Group.")

 

Slide 64:

Learning Objective #3

Write User Need

  • Review rules for a well-written user need
  • Uniquely identifiable
  • Identifies one major desired capability
    • Explains the need, not a "shall" type of statement
  • Solution free
  • Capture rationale

 

Slide 65:

Learning Objective #3

Configure Signal for Intersection Layout

Uniquely Identifiable

UN 2.1:

 

Slide 66:

Learning Objective #3

Configure Signal for Intersection Layout

Identifies One Major Desired Capability

UN 2.1: The agency needs a signal controller that can be safely configured to control any intersection within its jurisdiction, including those with atypical layouts.

 

Slide 67:

Learning Objective #3

Configure Signal for Intersection Layout

Solution Free

UN 2.1: The agency needs a signal controller that can be safely configured to control any intersection within its jurisdiction, including those with atypical layouts.

 

Slide 68:

Learning Objective #3

Configure Signal for Intersection Layout

Capture Rationale

UN 2.1: The agency needs a signal controller that can be safely configured to control any intersection within its jurisdiction, including those with atypical layouts.

This will result in lower overall maintenance costs for the Maintenance Division. However, the operators must still be able to control every intersection, including 6-legged intersections. In addition, due to the safety critical nature of this information coupled with the static nature of the information, this process should require the presence of a field technician to verify any change.

 

Slide 69:

Learning Objective #3

Monitor Signal Timing

UN 4.1: The agency needs a signal controller that will allow the management system to monitor the status of each signal indication with a one second resolution.

The agency needs a way to remotely verify that the traffic signal is operating as expected.

 

Slide 70:

Activity. A placeholder graphic with an image of hand over a computer keyboard to show that an activity is taking place.

 

Slide 71:

Learning Objective #3

Which of the following components is not part of a well-defined user need?

Answer Choices

  1. Unique Identifier
  2. Major capability
  3. "Shall" statement
  4. Rationale

 

Slide 72:

Learning Objective #3

Review of answers

A small graphical red and yellow X representing incorrect.a) Unique identifier
Incorrect; each need should have an identifier so that it can be uniquely referenced.

 

A small graphical red and yellow X representing incorrect.b) Major capability
Incorrect; the major capability is the central idea in a user need.

 

A small graphical green and yellow check mark representing correct.c) "Shall" statement
Correct! "Shall" statements should only appear in requirements, not user needs.

 

A small graphical red and yellow X representing incorrect.d) Rationale
Incorrect, the rationale should be included so that the reader can understand why the feature is being requested.

 

Slide 73:

Summary of Learning Objective #3

Identify and Write User Needs for ASC

  • User needs are not defined in NTCIP 1202
    • Agencies must develop based on stakeholder input and literature
    • Major capabilities can be extracted from the standard and mapped to stakeholder input
    • User need should fully document justification along with major capability
    • Users should consider cost implications before extending the standard

 

Slide 74:

Learning Objective #4—Stakeholder Desires vs. Realistic Requirements

  • NTCIP 1202 provides an excellent starting point for all standardized functionality
  • Some features were deemed to be too early to standardize
    • Adaptive control
  • Less common features were not defined in NTCIP 1202
    • Flashing yellow arrow
    • Leading pedestrian interval
  • Stakeholders may identify other capabilities that are not addressed by the standard

 

Slide 75:

Learning Objective #4

Examples of Extended Features

  • Consider whether any non-standard capabilities are really needed
    • Will likely be a custom/proprietary solution
    • Determine if there are alternatives that stakeholders will consider
  • If still needed, fully document the user need in the Concept of Operations
  • Consider cost implications of extended features
    • Specification
    • Testing
    • Maintenance of proprietary solution

 

Slide 76:

Summary of Learning Objective #4

Stakeholder Desires vs. Realistic Requirements

  • NTCIP 1202 standardizes the most common ASC features
  • Stakeholders may want some additional features
  • Non-standard features will increase life-cycle costs

 

Slide 77:

Learning Objective #5—Explain How to Evaluate Conformance

  • Understand the minimum conformance requirements
  • Appreciate how backwards compatibility is handled

 

Slide 78:

Learning Objective #5

Evaluating Conformance to NTCIP 1202

  • NTCIP 1202 does not define SEP "requirements," but does define conformance
    • Mandatory features of mandatory conformance groups must be supported
    • Many of the conformance groups reference objects defined in NTCIP 1201
  • If user needs do not trace to these items, it may suggest an incomplete analysis
    • NTCIP mandatory features are generally very basic requirements

 

Slide 79:

Learning Objective #5

Backwards Compatibility

When considering major capabilities, one must also consider if different versions of equipment will need to interoperate

  • If any differences exist in the specifications or design, the new equipment may have to be designed to work with both the older and newer versions
  • From a user need perspective, this just needs to be recorded so that the requirements and design properly accommodate this need

 

Slide 80:

Learning Objective #5

Backwards Compatibility

The major backwards compatibility issues related to NTCIP 1202 include:

  • Database transaction feature (NTCIP 1201 v01 to v02)
  • Daylight savings time (NTCIP 1201 v02 to v03)
  • Logic in setting local time (NTCIP 1201 v1 to v2)
  • Special function output state (NTCIP 1202 v01 to v02)

Each change has resulted from identifying ambiguities or problems in the initial version of the standard; your specification needs to clarify how existing equipment has interpreted these ambiguous features.

 

Slide 81:

Activity. A placeholder graphic with an image of hand over a computer keyboard to show that an activity is taking place.

 

Slide 82:

Which is the best way to complete this user need?

UN 5.1: Operators need the central system to_.

Answer Choices

  1. Work with Manufacturer X Model 1 controllers that are currently deployed as these are too costly to update.
  2. Support dbErrorType, dbErrorID, dbTransactionID, and dbMakeID.
  3. Support backwards compatibility for older controllers.
  4. Support NTCIP v01 and NTCIP v02 so that it can work with older controllers that are too costly to update.

 

Slide 83:

Learning Objective #5

Review of answers

A small graphical green and yellow check mark representing correct.a) Work with Manufacturer X Model 1 controllers that are currently deployed as these are too costly to update.
Correct, this statement identifies a desired capability sufficiently to allow the designer to create a solution without additional information. It is also solution-free, and indicates the rationale.

 

A small graphical red and yellow X representing incorrect.b) Support dbErrorType, dbErrorID, dbTransactionID, and dbMakeID.
Incorrect, a user need should not define a specific solution; it should describe the capability so that a user can understand it and provide a justification.

 

Slide 84:

Learning Objective #5

Review of answers

A small graphical red and yellow X representing incorrect.c) Support backwards compatibility.
Incorrect, this statement does not define the type of backwards compatibility or provide a justification.

 

A small graphical red and yellow X representing incorrect.d) Support NTCIP v01 and NTCIP v02 so that it can work with older controllers that are too costly to update.
Incorrect, this statement does not identify a valid standard number nor does it address how to resolve the ambiguities that led to the revision of the standard.

 

Slide 85:

Summary of Learning Objective #5

Explain How to Evaluate Conformance

  • NTCIP 1202 defines a minimum set of items that must be supported to claim conformance
  • Features within NTCIP 1202 depend on NTCIP 1201
  • There have been multiple versions of the standard and users should consider whether this will be an issue within their system

 

Slide 86:

Learning Objective #6—Relationship of Needs to Requirements

  • Introduce the concept of a traceability table
  • Awareness of follow-on module

 

Slide 87:

Learning Objective #6

Needs to Requirements

User needs should be traced to their requirements

  • Can be done in a table format
  • Similar to Protocol Requirements List (PRL) in SEP-based NTCIP standards
    • Does not need a conformance column since it only includes items that are needed for your project
    • Assist deployments by providing a checklist

 

Slide 88:

Learning Objective #6

Needs to Requirements

  • Unique User Need ID and title reference the precise user need
  • Requirements uniquely reference the requirements traced to the need

User Need ID

User Need

RID

Requirement

 

Slide 89:

Learning Objective #6

Needs to Requirements

User Need ID User Need RID Requirement

1

Architectural User Needs

1.1

Live Data Exchange

1.2

Logged Data Exchange

1.3

Support Legacy Communication Networks

2

Configure User Needs

2.1

Safely Configure Signal for Intersection Layout

3

Control User Needs

3.1

Control Selection of Timing Pattern

 

#.#

See module A315b

4

Monitor User Needs

4.1

Monitor Signal Configuration

4.2

Monitor Signal Timing

4.3

Monitor Timing Pattern Selection

4.4

Monitor Signal Diagnostics

5

Backwards Compatibility User Needs

5.1

Manufacturer X Model 1

 

Slide 90:

Learning Objective #6

Needs to Requirements

  • User needs describe what features the device needs to support and why
  • Functional requirements support and satisfy the user needs into detailed, measurable specifications
  • The traceability table visually maps the relationships between user needs and functional requirements

 

Slide 91:

Learning Objective #6

Functional Requirements

Functional requirements will be covered in the next module(s)

  • A315b: Specifying Requirements for Actuated Traffic Signal Controllers (ASC) Based on NTCIP 1202 Standard

 

Slide 92:

Activity. A placeholder graphic with an image of hand over a computer keyboard to show that an activity is taking place.

 

Slide 93:

Learning Objective #6

The benefit of the needs to requirements table is that it:

Answer Choices

  1. Maps needs to requirements
  2. Provides a high-level summary of the features
  3. Provides a convenient checklist during deployment
  4. All of the above

 

Slide 94:

Learning Objective #6

Review of answers

A small graphical red and yellow X representing incorrect.a) Maps needs to requirements
Incorrect, one of the main purposes is to show this mapping

 

A small graphical red and yellow X representing incorrect.b) Provides a high-level summary of the features
Incorrect, the table provides a quick reference to each major feature with a lookup reference

 

A small graphical red and yellow X representing incorrect.c) Provides a convenient checklist during deployment
Incorrect, this becomes valuable during the testing of the equipment once delivered

 

A small graphical green and yellow check mark representing correct.d) All of the above
Correct, the best answer is that they are all true

 

Slide 95:

Summary of Learning Objective #6

Relationship of Needs to Requirements

  • User needs should be summarized in a table
  • Table will be used to map needs to requirements in next phase for traceability
  • Requirements will provide measurable statements for subsequent testing

 

Slide 96:

What We Have Learned

  1. NTCIP 1202 does not include SEP. content.
  2. A description of ASC functionality and a practical baseline conformance statement for NTCIP 1202 can be found in NEMA TS2 .
  3. Major capabilities can be extracted from NTCIP 1202..
  4. Requiring non-standard features will increase life-cycle costs.
  5. Conformance to the standard only requires minimal support of the mandatory objects contained in the mandatory conformance groups.
  6. User needs should be mapped to requirements in a table.

 

Slide 97:

Resources

  • NTCIP 1201: Global Object Definitions
  • NTCIP 1202: Object Definitions for ASC
  • NEMA TS2: Traffic Controller Assemblies with NTCIP Requirements
  • NTCIP 9001: NTCIP Guide
  • IEEE 1362: Concept of Operations Document

 

Slide 98:

Questions? A placeholder graphic image with word Questions? at the top, and an image of a lit light bulb on the lower right side.

 

Slide 99:

Next Course Module

A315b: Specifying Requirements for Actuated Traffic Signal Controllers (ASC) Based on NTCIP 1202 Standard

  • Explains how to write ASC requirements
  • Derives sample requirements to satisfy needs
  • Explains how to show the relationship between requirements and the design from the standard