Scope Statements

1

Scope Statements

Mark E. Sampson

EMIS 8340

Systems Engineering Tool—applying tools to engineering systems

2

Scope Statement for your team problem

This course will use a problem throughout the various classes to teach tool application—the finished product will be a 40% of your grade.

Teams will define a simple need they want to address and develop a scope statement to establish a foundation on which to build requirements.

We will use the scope statement outline suggested by [Hooks & Farry 2001]

3

Define needs, goals, and objectives…

What is the need you are going to meet?

Is…• Derived from a problem • Why we are doing something

Is not…• The product• Subject to change

Down in writing, available to everyone

[SE Handbook 4.1] [Hooks 2001]

4

Brainstorming a need…

What is the need is your team going to meet?

Brainstorming with yellow sticky notes

Rules: 1. Collect as many ideas as possible2. No criticism, nothing’s too off the wall3. Build on each other’s ideas4. Write all the ideas down, organize/discuss them later5. Time limit:15-30 minutes…

Example: Cheap way to get things into space

5

Establishing goals & objectives…

Goals—define things to accomplish to meet need

Objectives—define how we will know when we’ve arrived

Example: Need: cheap way to get things into space

Goal: produce new space vehicle that cuts costs in half

Objective: 30% less weight to liftcost of launch reduced by 50%

[SE Handbook 4.1] [Hooks 2001]

6

Assignment #1

1. Select a project for your team2. Define the need, goal, and objects for your project3. Deliver your needs, goals, and objectives to critical

review in class.

7

Identify Stakeholders…

Who/What is involved in any way with your product?

• Who affects or is affected by this product?• Anyone/Anything who can help or hurt your project.

Example: FAA Air Traffic Control System—air traffic controllers, ground controllers, maintenance, airlines, pilots, public, Congress, weather systems,…

What is their point-of-view?

• Finance--reduced cost• Marketing--new market/increased market share• Manufacturing—reduced defects, no process changes,...

[SE Handbook 4.1] [Hooks 2001]

8

Context Diagrams…

How do I know who the stake holders are?

[SE Handbook 4.1] [Hooks 2001]

Product

Engineering

Customer Maintenance Safety

Testing

Manufacturing

Materials

Marketing

ReliabilityFinancePurchasing

Software

EMI

Suppliers

9

Fishbone Diagram…

How do I know who the stake holders are?

1. Identify all possible contributors to your problem.

2. Identify all possible impacting Issues to those contributors

3. …keep going

Training budget

http://www.maaw.info/SixSigmaSummary.htm

Finance is a potential stake

holder

10

Correlation Diagrams…

How do I know who the stake holders are?

Table 1: Age And Gasoline Price Table

Year My Age Gasoline Price

1950 0 $0.06

1955 5 $0.12

1960 10 $0.27

1965 15 $0.15

1970 20 $0.52

1975 25 $0.64

1980 30 $0.76

1985 35 $0.89

1990 40 $1.10

1995 45 $1.19

2000 50 $1.40

http://www.isixsigma.com/library/content/c030111a.asp [Sloan 2004]

…highly correlated events indicate interfaces and thus potential stakeholders

11

Google Search…

How do I know who the stake holders are?

…using various web-basedSearch engines to seekout related items.

…number of interestingvisualization techniquesthat can also help…

[SE Handbook 4.1]

12

Assignment #2

1. Identify Stake Holders2. Define their point of view, what’s important to them3. Deliver your stake holders to critical review in class.

13

Identify Drivers & Constraints…

External things that affect your product that you can do nothing about.

Example: Cost, regulations, higher level requirements, existing/legacy systems, schedule, standards,…

[SE Handbook 4.1] [Hooks 2001]

Product

ExpectationsCost Contracts Standards

Test Equipment

Manufacturing processes

Material constraints

Schedule

Safety Issues LegalLead time

Legacy Systems

Environment

Supplier Capabilities

14

Assignment #3

1. Identify Drivers & Constraints2. …they will need to be quantified and agreed to 3. Deliver your Drivers & Constraints to critical review in

class.

15

Identify operational concepts, scenarios, use cases,…

A scenario or story of a day-in-the-life of your product describing why this is a problem today, how this will be different when your solution is there

Example: Phone rings while driving…

Current Scenario: Driver fumbles for his phone, drops it on the floor, bends down to get it , crashes into the car ahead of him…

Future Scenario: Radio automatically turns down, user says “answer phone”, phone answers, user starts conversation…user says hang up, radio comes back on,… [SE Handbook 4.1] [Hooks 2001]

16

Identify operational concepts, scenarios, use cases,…

• A critical means of getting the approach across• Speak for you when you’re not there

Developed originally for operations, but cover the entire life cycle

• Development, Test, Storage, Upgrade, Transport, Disposal, Maintenance,…

• From a variety of viewpoints…customer, testers, users, manufacturing, etc.

• Start at a high level and work your way down…

[SE Handbook 4.1] [Hooks 2001]

17

Some tools…

Pictures, IDEF OV1, Powerpoint,…Brainstorming, Delphi Techniques, TRIZ…Use Cases and Actors

J-STARSw ATR

U-2

CAOC

UAV

DCGS

AEGIS

USMCTAOC

AIR DEFENSETOC

TADITADIL L

NETNET

TADITADIL L

NETNET

BCC

ARMY TacticalOperations Center

XX

XX

XXX

XX

TCT Kill Chain TCT Kill Chain Engaged by a Joint Battle ForceEngaged by a Joint Battle Force

18

TRIZ…Theory of Inventive Problem Solving

Statistical Design Institute… Statistical Design Toolkit for Design for Six Sigma, includes a TRIZ tool.

What is TRIZ—approach to dealing with engineering contradictions

Presentation from Dr. George Chollar/Dr. JessePeplinski www.stat-design.com

19

Assignment #4

1. Develop an operational concept/scenario that describes why this is a problem

2. Develop an operational concept that describes how your solution will solve this problem

3. Deliver your operational concept to critical review in class.

Caution about “Pre-selection Error” Don’t let your scenario drive you towards a solution yet, we still trying to define our scope

[Hooks 2001]

20

Define External Interfaces

• Capturing interfaces for future reference

What do you have to interface with?

Applications Study: Henry Ford’s first car and Explorer Tire Recall Upon completion of his first automobile in his workshop, Henry Ford was

amazed to discover it didn't fit through the door (Henry Ford, p.30, A. Knopf, 1966)

 …or a more recent example from the news… May 20, 2001--Ford Motor Co. is recalling 50,000 brand new Explorers

because an assembly line conveyor belt that was too narrow for the wider 2002 model may have cut the tire tread (http://abcnews.go.com/sections/us/DailyNews/tires_recall_wire010520.html)

[SE Handbook 4.1] [Hooks 2001]

21

External Interfaces…

[Lacy 1992] [Hooks 2001]

Software

Test Equipment

People

Printer

Power

EMI

Networks

Storage

Be sure to ask the question, “What is the worst thing otherelements could do to you across this interface?” [Kuchta, 1989]

…and defend against it! [Hooks 1999]

22

Methodology: Context Diagrams

…identifies the inputs/outputs for the system

• Helps identify constraints• Identifies stakeholders

In our dental hygiene case, shows all interests in our system

What’s the difference between stake holders and external interfaces? [Armstrong 1993]