Engineering Design GE121 Finding Answers to the Problem Part III / IV

1. Engineering DesignGE121Finding Answers to the ProblemPart III / IV Lecture 12A

2. Limiting Design Space to a Usable Size • Pragmatic (practical) issues related to how an artifact will be used, and how it will be made • Provides ‘guideposts’ for development of the search space – may narrow rather than expand the search space • Design alternatives must be functions of • User Needs • Available Technologies • External Constraints • (and some common sense!)

3. Limiting Design Space to a Usable Size(Continued) • Example – Design of vehicles for a campus transportation system • Candidate Vehicles • Simple bikes • High Tech bikes • Recumbent bikes • Tricycles • Rickshaws • User Needs may dictate consideration of: • Parking availability • Carrying Packages • Access for Handicapped

4. Limiting Design Space to a Usable Size(Continued) • Available Technologies may affect design alternatives: • Materials (affects appearance, manufacturing, price) • External Constraints may limit design alternatives: • Team’s area of expertise (may be expert in tricycle design) • Available Manufacturing Facilities (may dictate material) • Practical Considerations – Common Sense! • Invoke and apply constraints (similar to user needs, as above) • Freeze the number of attributes (avoid those unlikely to seriously affect design – i.e. color) • Impose some order on the list (which functions / features are most important) • Get Real! (watch out when silly / infeasible options are repeated too often)

5. Morphological Charts: Organizing Functions and Means to Generate Designs that Work • Morphological Charts - Important Alternative Development tools • Chart or Matrix • Functions or Key Features are listed in the first column • Alternate Means of achieving each function are given in that function’s row • Generating the Means for each function can be a highly creative process • Means do not have to be Words – some designers use sketches or thumbnails to show some alternative means

6. Morphological Charts (continued) • The Morphological Chart can be used to generate Complete Alternatives • Leftmost column lists ALL functions • Selecting a means from EACH row guarantees that the solution satisfies all required functionality • Will NOT, however, guarantee that • Alternatives will WORK • Or even be internally consistent (see Fig. 5.2b) • Judgement is still required • This approach can result in a HUGE number of alternatives

7. Morphological Charts (continued) • Start with Functions • Contain Beverage • Material for Beverage Container • Provide Access to Juice • Display Product Information • Sequence Manufacture of Juice and Container

8. Morphological Charts (continued) • Add Means for Each Function • Contain Beverage: Can, Bottle, Bag, Box • Material for Beverage Container: Aluminum, Plastic, Glass, Waxed Cardboard, Lined Cardboard, Mylar Films • Provide Access to Juice: Pull-Tab, Inserted Straw, Twist-Top, Tear Corner, Unfold Container, Zipper • Display Product Information: Shape of Container, Labels, Color of Material • Sequence of Manufacture: Concurrent , Serial

9. Morphological Charts(continued) Create Morph Chart (words) Fig. 5.1 p104 Or – Use Thumbnails (next page)

10. Fig. 5.3 p106

11. Morph ChartGenerating a Complete Alternative • Morph Chart showing one means for each function which can be combined to form one complete alternative that looks feasible Fig. 5a

12. Morph ChartComplete Does not Mean Feasible • Morph Chart showing a complete alternative that is not consistent – Glass Bottle with a zipper (zip-lok requires plastic) Fig. 5b

13. Managing Your Group • You may want to consider appointing someone to fill each of the following roles: • Project leader • Scribe/recorder • Project file keeper • Report co-ordinator

14. C-Sketch Method • It may be helpful to use the C-Sketch Method to generate ideas from your Morph Chart(examples from microlaryngeal stabilization device)

15. Activity • Create a Morph Chart for your project Start with a List of functions Brainstorm a List of Means for each Function Be Creative in your Brainstorming!