EML4550 - Engineering Design Methods

1. EML4550 - Engineering Design Methods Concept Generation Generating ideas and design concepts Concept Selection Settling on one or more promising ideas to pursue to final design Hyman: Chapter 6 and Sec. 9.1 & 9.2 Ulrich and Eppinger: Chapters 5 and 6 Dym and Little: Sections 6.1 – 6.3

2. Select Product Concept Plan Design/ Development Project Perform Economic Analysis Analyze Competitive Products Concept Development Diagram (Hyman Chapter 6) Establish Target Specs Generate Product Concepts Identify Customer Needs Refine Specs Mission Statement Action Plan

3. Concept Generation • A ‘conceptual’ design is an approximate representation of the final product • Sketches, 3-D renderings, ‘back-of-the-envelope’ calculations to assess feasibility • Concept generation is typically ‘low-cost’ (5% of project) and somewhat time-consuming (15% of schedule) • Need to explore ALL possible concepts, structured approach to avoid pitfalls: • Consideration of only a few options, failure to consider competitors’ concepts, involvement by just a few people, failure to follow through partial solutions, failure to see entire categories of solutions

4. Concept Generation (cont’d) • “Creative” part of the design process • Least structured part of the process • It is OK to allow some “chaos” during project inception (shake down the ideas) • However, in order to avoid major oversights, we need to introduce some structure to the concept generation phase

5. Models for the creative process • Wallas model • Fabun model • CEF model • Consolidated model

6. Wallas model (1926) • Preparation • Clarify and define problem (recognizing the need, defining the problem) • Incubation • Formative stage, mind is relaxed and free to receive ideas • Illumination • First conscious recognition of an idea (“Eureka!”) • Verification • Reality check on the idea

7. Fabun model (1968) • Desire • Equilibrium broken by appearance of a problem • Preparation (same as Wallas) • Manipulation • Mind actively manipulates ideas/gathers information • Incubation (same as Wallas) • Intimation • Realization we are on the right track • Illumination (same as Wallas) • Verification (same as Wallas)

8. CEF (Creative Education Foundation) model (1976) • Fact finding • Collect all facts that may bear on the problem • Problem finding • Articulate problem formulation(s) • Idea finding • Solutions are presented • Solution finding • Solutions are evaluated and one is selected • Acceptance finding • Customer buy-off and implementation

9. Consolidated model • Exploration • Active and concerted search for new ideas with possible frustrating results (need to pursue further) • Incubation • Formative stage when extended period of relaxation without a conscious effort to solve the problem • Intimation • Resumption of search effort with the feeling of making progress • Illumination • Breakthrough that produces a new and attractive idea

10. Barriers to Creative Thinking • Perceptual (inability to properly perceive problem, unnecessary inference, etc. Most frequently encountered) • Patterns, boundaries (can’t think outside the box), illusions, lenses (can’t see the forest for the trees), meanings • Cultural (imposed by society, how to think unconventionally) • Environmental (anything in the surrounding that stifles creativity, both physical or in terms of personal work conditions such as overly critical and rigid behavior) • Emotional (emotional baggage from personal life) • Intellectual (not enough knowledge on the topic  life-long learning to update one’s knowledge)

11. Removing Barriers/Techniques to Generate Alternatives • Lateral thinking (as opposed to vertical thinking) • Generate as many ideas as possible (crazy is good) • Do not go deep into any one idea • Do not criticize or pre-judge ideas (don’t evaluate until you conceptualize all options. Need will power and discipline to resist) • Perseverance • Invention is 95% perspiration, 5% invention (Edison) • Mental push-ups • Engage on creative design activities often • Get involved with other projects

12. Removing Barriers/Techniques to Generate Alternatives (Cont’d) • Making lists • As an exercise, take common objects and list no less than 20 uses • Get used to thinking of common objects in uncommon ways • Word games • “Cryptic” crossword puzzles (“meaning” barriers) • Solving puzzles • Classical puzzles, cubes, 2-D boards, etc. (“boundary” barriers)

13. Concept Generation Practical Approaches and Examples

14. Concept Generation Methodology Clarify the problem Search externally Search Internally Explore systematically Reflect on the process and the solutions

15. Clarify the problem • Understanding (needs, specs, objectives) • Decompose complex problems into simple sub-problems • Decomposition by function • Create ‘boxes’ and function diagrams • Create ‘boxes’ and flow diagrams • Decomposition by sequence of user actions • Decomposition by needs • Decomposition by field of competence • Identify critical sub-problems and concentrate early efforts on them

16. Search externally • Interview lead users (customers) • Consult experts (consultants) • Search patents • Databases: Lexis/Nexis, Dialog, etc. (through Library) • US Patent & Trademark Office ( http://www.uspto.gov ) • Search published literature • Databases (through Library) • Trade journals and magazines • Benchmark related products • Thomas Register

17. Search internally • Ground rules: • Suspend judgment until after exercise is complete • Generate a lot of ideas • Accept ideas that may appear infeasible • Use graphical and physical media (models) • Use both group and individual sessions • Where ideas come from: • Make analogies • Wish and wonder • Individual ideas (related stimuli) or random ideas (unrelated stimuli) presented to group • Set quantitative goals (‘nobody leaves until…’) • Use gallery method – display a large number of ideas visually for discussion

18. Explore systematically • The internal and external searches should have generated many ideas (or solution “fragments”) - potentially hundreds if the problem is complex enough • Objective is to organize these ideas so that they can be properly evaluated later • Concept Classification Tree • Concept Combination Table • Managing the Exploration Process

19. Concept Classification Tree • Identification of independent approaches to the problem • Helps clarify the choices; can be used to delegate individual efforts • Pruning of less promising branches • Foster an early elimination • Exposure of undue emphasis on certain branches (solutions) • By contrast, finding branches that were overlooked • Refinement of problem decomposition for a particular branch

20. Nuclear Fuel Hydraulic Pneumatic Electrical Chemical Explosive Fuel-Cell Magnet Battery Accept Energy Store Energy Concept Classification Tree: Example Energy Source

21. Concept Combination Table • Decompose system by functional steps, or by physical sub-systems (or any other decomposition that makes sense) • Enumerate solution-fragments for each of the categories • Make a table with these entries • Problem solution can be arrived at by combining entries from the table (combination of solution-fragments)

22. Example

23. Morphological Chart Functions Medium Water Alcohol Air Reservoir Square Tank Rectangular Circular Tank Tank Support Steel Beams Wood Table

24. Concept Generation: Implications to Project • Statement that clarifies the problem and sets boundaries on its scope • A record of the search for ideas (internal and external) • Tables or diagrams presenting all the ideas generated, and concepts that were considered • An exhaustive and well-organized set of ideas and/or conceptual designs