introduction to engineering design william oakes, p.e
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Introduction to Engineering Design
William Oakes, P.E.
Learning Objectives
At the end of this session, you will be able to:
1. Describe design
2. List at least three steps in the EPICS design process
3. Identify resources to help with design
4. Describe how users are important to the design process
Design is…
One of the activities of engineering. Design Development Research Test Analysis Production Sales Technical Support OtherSource: Oakes, Leone, and Gunn (2004). Engineering
Your Future. Okemos, MI: Great Lakes Press.
Many definitions of design…Design is artDesign as problem solvingDesign activity as applying scientific
knowledgeDesign is a social process in which
individual object worlds interact, and design parameters are negotiated.
Source: Dr. Robin Adams ENE 696G course notes
Crismond (2007) draws from many sources in his definition of design as “’goal-directed problem-solving activity’ (Archer, 1965) that initiates change in human-made things (Jones, 1992), and involves optimizing parameters (Matchett, 1968) and the balancing of trade-offs (AAAS, 2001) to meet targeted users needs (Gregory, 1966).”
Source: Crismond, D. (2007). Contrasting strategies of beginning and informed designers: One representation of learning progressions in engineering design.
The Design Process
Few Specifications
Many Specifications
Design Process
Infinite Variety of Designs
Most -----Least InfluentialChoices
One Design
Design is done by many disciplines
=====>
The Design Process
Many formal models for the design process ME uses Ullman’s Model for Design
o The Mechanical Design Process, McGraw Hill, 1997, 2003
o 6 steps Engineering Your Future
o 10 steps Different Companies use different models
o They use a process EPICS teaches a model that fits our
community-based design
Multiple Valid Solutions
Examples: • Cars• Cell phones • Computers
Good/Bad Design - Activity
Think of 1 thing you think was well-designed. Think of 1 thing you think was poorly designed.
For each item:o ItemoWhy you think it was well/poorly designedoWhat did the designer understand/not
understand in the design that made it good/bad.
Good/Bad Design Activity, cont
Get in groups of 3 or 4Talk about your answersPick one or two things from the group
to present:o ItemoWhy you think it was well/poorly
designedoWhat did the designer understand/not
understand in the design that made it good/bad.
EPICS Balance
Service-learning is a balance of the learning of design and the service we contribute the communities through completed designs and support
Service• To our partners,
meeting needs in the community
Learning• Becoming good
designers, professionals & active citizens
Complimentary goals that enhance each other
From IDEO HCD
ToolkitWhat do people
desire?
What can be financially viable?
What is technically and organizationally
feasible?
EPICS Design Process
Six Phases
1. Problem Identification
2. Specification Development
3. Conceptual Design
4. Detailed Design
5. Production
6. Service/Maintenance
7. Redesign or retirement
The EPICS Design Cycle
Specification Development
Detailed Design
Production
ServiceMaintenance
Redesign
Retirement
Problem Identification
ConceptualDesign
Disposal
Human-centered Design: Basic Principles
Early focus on usersDesigning for and with usersEmpirical measurement and
evaluationIteration
Human Centered Design Formal/Informal Interviews
o Focus groups– interviews with multiple people
Personao Prototypical user, described in detail
Scenarioso “before and after” stories of your persona using
your product• Focus on the user’s need and how their life might be
improved
Role-playing: put yourself in the user’s shoes, chair, and/or spaceo Empathic modeling: Simulating the
sensory/motor/cognitive constraints
• Interactions with Stakeholders• Prototypes/communications at all stages
Human-Centered Design
EPICS Design Process
Six Phases
1. Problem Identification
2. Specification Development
3. Conceptual Design
4. Detailed Design
5. Production
6. Service/Maintenance
7. Redesign or retirement
Project Identification Phase: Goal is to identify a specific, compelling need to be addressed
Common tasks
Conduct needs assessment (if need not already defined) Identify stakeholders (customer, users, person maintaining project,
etc.) Define basic stakeholder requirements (objectives or goals of projects
and constraints) What will be the deliverable?
Determine time constraints of the project How long will it take?
Gate 1: Continue if have identified appropriate EPICS project that meets a compelling need
Example….Project Identification Phase
One of the deliverables is the Project CharteroDescription – Describe and summarize
what you or your team will be doing. • E.g., What is the problem that you will be solving
and for whom?
oObjectives- List the project objectives. • E.g., Why are you doing the project (i.e., what is
the motivation or desired need for the project?)
Project Charter, continued
oOutcomes or deliverables• E.g., What are going to be the project
results?oDuration
• E.g., When will the project be started, and when will it meet the objectives and deliver the outcomes?
oCommunity Partners• E.g., With whom are you serving on this
project? oStakeholders
• E.g., Who will be affected by your project other than your customer?
Specification Development Phase: Goal is to understand “what” is needed by understanding the context, stakeholders, requirements of the project, and why current solutions don’t meet need, and to develop measurable criteria in which design concepts can be evaluated.
Understand and describe context (current situation and environment) Create stakeholder profiles Create mock-ups and simple prototypes: quick, low-cost, multiple
cycles incorporating feedback Develop a task analysis and define how users will interact with project
(user scenarios) Compare to benchmark products (prior art) Develop customer specifications and evaluation criteria; get project
partner approval
Gate 2: Continue if project partner and advisor agree that have identified the “right” need, and if no existing commercial products meet design specifications.
Tasks:• Basic functional decomposition
• User interaction – crude prototypes as communication devices
• Benchmark research
• Customer specifications development
• Develop Design Specifications - MEASURABLE
Primary Function
Sub-function Sub-function
Sub-function Sub-function
Primary FunctionPrimary Function
Sub-functionSub-function Sub-functionSub-function
Sub-functionSub-function Sub-functionSub-function
Specification Phase
Specification Development
Deliverables- oProject Specification Document
• Measureable specifications
oMock-ups or rough prototypes to help narrow the specifications
Interacting with the community partneroUser-centered, human-centered
Spec or Requirement
Origin How will you know if you achieved it?
Completed?
1. Sound audible in classroom
Project Partner Requirement
Test in classroom
1.1 Sound range between 15 dB and 85 dB
Project Partner Requirement of audible sound
1.2 Variable output
2. Project should be educational
Project Partner Requirement
Pre-, post-test?Interview students?
Conceptual Design Phase: Goal is to expand the design space to include as many solutions as possible. Evaluate different approaches and selecting “best” one to move forward. Exploring “how”.
Conduct Functional Decomposition Brainstorm several possible solutions Create prototypes of multiple concepts, get feedback from users, refine
specifications Evaluate feasibility of potential solutions (proof-of-concept prototypes);
select one to move forward Interaction with users
Gate 3: Continue if project partner and advisor agree that solution space has been appropriately explored and the best solution has been chosen.
• Take functional decomposition and brainstorm on each of the functions• How can we ______ ?• Capture the best of each idea• Rebuild the system as combinations
Primary Function
Sub-function Sub-function
Sub-function Sub-function
Primary FunctionPrimary Function
Sub-functionSub-function Sub-functionSub-function
Sub-functionSub-function Sub-functionSub-function
Conceptual Design
Deliverables- oProject Conceptual Design ReportoSystems level design
• Details need to be designed
oSketch/mock-up/prototype demonstrates concept
Detailed Design Phase: Goal is to design working prototype which meets functional specifications.
Common tasks
Design/analysis/evaluation of project, sub-modules and/or components (freeze interfaces)
Complete DFMEA analysis of project Prototyping of project, sub-modules and/or components Field test prototype/usability testing
Gate 4: Continue if can demonstrate feasibility of solution (is there a working prototype?). Project Partner and advisor approval required.
Detailed Design Deliverables
o Project Detailed Design Report• Full details of all parts• Dimensions, sizes, all details• Documentation of all parts
o Full prototype version of project
Delivery Phase Tasks: Goal is to refine detailed design so as to produce a product that is ready to be delivered! In addition, the goal is to develop user manuals and training materials.
Common tasks: Complete project Complete user manuals/training material Complete usability and reliability testing Complete delivery review
Gate 5: Continue if Project Partner, Advisor and EPICS Admin agree that project is ready for delivery!
Service/Maintenance Phase Tasks
Common tasks: •Evaluate performance of fielded project•Determine what resources are necessary to support and maintain the project
Gate 6: Project Partner and Advisor approve continued fielding of project. If not, retire or redesign.
Retirement or Redesign
Fielded projects are evaluated with partners for repair, retirement or redesign
The EPICS Design Cycle
Specification Development
Detailed Design
Production
ServiceMaintenance
Redesign
Retirement
Problem Identification
ConceptualDesign
Disposal
Iterations in the Design Process
Disposal
Specification Development
Detailed Design
Production
ServiceMaintenance
Redesign
Retirement
Problem Identification
ConceptualDesign
Iteration and Test
Generate Ideas
Define Measurable Specifications
Implement
Test
Go to next phase
Generate Ideas
Define Measurable Specifications
Implement
Test (Users)
Back to previous phase
Iteration and testing
Prob ID
Spec Dev
Con Des
Det Des
ProdMain and serv.
• Document• Why advanced• Why interated
• Tests are often done with stakeholders during the design process
Human-Centered Design
Curriculum Diagram
Figure 1 (DRAFT skeleton): EPICS Design Model
Exit 1: Problem Identification Rd.
Exit 2: Specification Development Ave Road
Exit 4: Detailed Design St.
Exit 7: Retirement Rd.
Seeking and Selecting
Each phase of the design process requires creative solutions and has a divergent component where ideas are sought and
a convergent component where options are selected
Diverge Seek Possibilities
ConvergeNarrow Choices
Problem Identification
Specification Development
Conceptual Design
ConvergeNarrow Choices
ConvergeNarrow Choices
Diverge Seek Possibilities
Diverge Seek Possibilities
Why is design difficult?
Engages different types of thinking
Requires designers to manage so many ideas and aspects
Addresses different types of problems
Good design… Good designs involve diverse perspectives
and expertise IDEO – industry leader in design and
innovationo Design thinking is a crucial business asset—one
that can, indeed, move a company forward and improve the bottom line. To optimize this impact, (we) advise thoughtfully structuring the innovation process. They stress working on projects that improve people’s lives..
- Ryan Jacoby and Diego Rodriguez, Innovation, Growth, and Getting to Where You Want to Go, Design Management Review Vol. 18 No. 1
Human Centered Design Formal/Informal Interviews
o Focus groups– interviews with multiple people
Personao Prototypical user, described in detail
Scenarioso “before and after” stories of your persona using
your product• Focus on the user’s need and how their life might be
improved
Role-playing: put yourself in the user’s shoes, chair, and/or spaceo Empathic modeling: Simulating the
sensory/motor/cognitive constraints
Caution!
These tools should not replace getting feedback and information from the users and stakeholders themselves!
Just because you have “pretended” to have a disability or in a certain situation, doesn’t mean you understand what it really like for those users and stakeholders.
Prototypes
Prototyping….rough, quick, very iterativeo IDEO working with Gyrus ACMI to design
new apparatus for operating on delicate nasal tissues
oPrototype: whiteboard marker, 35 mm film canister and clothespin
oMouse for AppleoPrototype: roller ball from
tube of Ban Roll-on deodorant to the base of plastic butter dish
Personas Fictional character with all the characteristics of the
user Created after the field research (observations,
interviews) Members of the primary stakeholders (users) Depicts the "typical" or "average" individual in the
primary stakeholder group Include a name and picture, demographics, roles and
responsibilities, goals and tasks, motivations and needs, environment and context, and a quote that can represent the character's personality.
Personas May be several personas for the same group to
reflect diversity of that group Secondary personas, their needs should be met and
problems solved if possible. Create a common shared understanding of the user
group Prioritize the design considerations by providing a
context of the user needs Provide a human face and existence to a diverse
user group
Your Design Projects1. Problem Identificationo Using personas and role playing
2. Specification Development o List of specifications, early prototypes
3. Conceptual Designo Early prototype and proof of concept
4. Detailed Design
5. Production
6. Service/Maintenance
7. Redesign or retirement