Set-Based Design

PlanningPlanning

Product Development Process

ConceptDevelopment

ConceptDevelopment

System-LevelDesign

System-LevelDesign

DetailDesign

DetailDesign

Testing andRefinement

Testing andRefinement

ProductionRamp-Up

ProductionRamp-Up

Concept Development Process

Perform Economic Analysis

Benchmark Competitive Products

Build and Test Models and Prototypes

IdentifyCustomerNeeds

EstablishTargetSpecifications

GenerateProductConcepts

SelectProductConcept(s)

Set FinalSpecifications

PlanDownstreamDevelopment

MissionStatement Test

ProductConcept(s)

DevelopmentPlan

Review

Creativity/Brainstorming

Creativity is a divergent thinking skill in which we postpone judgment and try to see a situation from as many different perspectives as possible. Brainstorming is a term used for the creative generation of many ideas.

What Do We Do With Brainstorming?

• How quickly did you select an idea for your device?

• How many ideas did you generate before you got there?

• With brainstorming the idea is to go back and look at all of the ideas that you generated and generate many feasible ideas. (not to decide on an idea and then make a brainstorming list)

TriggersTools to bump yourself out of mental ruts.

• Other’s Shoes – Reconsider the problem from the perspective of a plumber, civil engineer, physician, child, attorney, basketball player, etc. You can keep this close to your personal comfort level by picking roles you know something about, like plumber perhaps, and then expand to more fanciful ones, like princess.

• Nature – How does nature deal with this issue, or how would you do it if you were Mother Nature?• Opposite – How would you solve the opposite problem (from “cut down a tree” to “grow a tree”)?

Or, consider the opposite of some of your ideas (from “cut with a saw” to join with “hot glue”).• Random – Use random words, pictures, movie titles, professor names to generate more ideas.• Analogy – Consider what has similar function but different appearance (automatic clothes washer

to washboard), what has similar appearance but different function (washboard to cheese grater), or what has a similar name and different use (bottle cap to baseball cap)?

• Craziest Idea – take the craziest idea and try use the kernel to get to a practical solution (“Cut down a tree with scissors” to “cut with large hydraulic shears”).

• Boundaries/Constraints – Remove, adjust, or explore the boundaries of the problem. (If the problem is a better way to wash clothes, what about recycling the old shirt into a new shirt instead of washing? Does it have to be “wash” or can it be “clean” or “deodorize”?)

• Anthropomorphize – Consider yourself to be the piece of equipment or process. Or consider yourself a molecule flowing through the system. (For “Why is this part failing?” think- “Am I getting hot anywhere, where do I feel the stress?”)

• Combine – Take different ideas and see what happens if you add them together, or combine them in some other way (Problem: “wash clothes” – combine “spray with a hose” and “pound on a rock” to “spray with wet rocks”)

Now what?

• Typically, use a concept selection technique to select one or two ideas for continuation.

• Set-based• Point-based

Courtesy Durward Sobek, Montana State University

Rather than pick the best!

Sobek and Ward define 11 principles that provide the framework for set-based design

1. Define the feasible regions– Decompose the overall design into functional elements– Develop feasible regions for performance and constraints

2. Communicate the sets of possibilities– Describes communication between functional groups (and with Chief

Engineer)– Attempt to develop a full understanding of each others capabilities and

needs– Don’t communicate your best idea (or your best idea at one operation

state)... Provide description of several options over a wide operation range

3. Look for intersections– Find regions where feasible designs from the different functions overlap– Negotiated between functional groups with the CE – Attempt to optimize total system, not individual parts

Sobek and Ward continuation of 11 principles that provide the framework for set-based design4. Explore trade-offs by designing multiple alternatives

– Develop alternative solutions– Develop a solid understanding of alternatives using the method that

makes most sense:• prototyping• analysis

5. Impose minimum constraint– Limit the design with only the necessary constraints– Example: provide broad functional requirements to suppliers

6. Narrow sets gradually, balancing the need to learn and the need to decide Develop understanding before making a decision Recognizes that design is a decision based process:

determine preferences generate alternatives generate expectations

CE driven

Sobek and Ward continuation of 11 principles that provide the framework for set-based design

7. Pursue radical and known solutions in parallel– Pursue unproven high pay-off solutions along with low risk backup solutions

8. Establish feasibility before commitment9. Stay within set once committed10. Control by managing uncertainty at process gates11. Seek robustness against physical, market, and design

variations– Create designs that work regardless of what the rest of the team decides to do

Rating alternative designs (Quick decision matrix)