Agenda

1. Agenda 1. Introduction 2. Venn diagrams 3. Functional flow block diagrams (FFBDs) 4. Other stimulation techniques 5. Axiomatic design 6. TRIS

2. 1. Introduction • Domains of system design • Topics for this course • Levels of invention • Need-driven design process • Models and techniques 1. Introduction

3. Domains of system engineering control electrical fire system chemical environmental industrial human metallurgical mining nuclear petroleum naval ship structural manufacturing biological other 1. Introduction

4. Topics for this course • Topics included • Architecture • Interfaces • Control • Signal processing • Environment • Test • Topics excluded • Design involving coding or manufacturing 1. Introduction

5. Levels of invention • Levels • 1: apparent solution -- 32% • 2: minor improvements -- 45% • 3: major improvement -- 18% • 4: radical change -- 4% • 5: discovery -- 1% • Basis • Genrich Altshuller -- inventor of TRIZ • Examination of 40,000 patents 1. Introduction

6. Need driven design process • Need to • Resolve uncertainty • Provide inputs to others 1. Introduction

7. Models and techniques (1 of 2) 1. Introduction

8. Models and techniques (2 of 2) 1. Introduction

9. 2. Venn diagram • Definition • Operations • Use for Venn diagrams • Example 2. Venniagram

10. Definition • Definition -- A figure consisting of a set of closed plane figures • Often used with set operations 2. Venniagram

11. Operations (1 of 5) • Sets and subsets • A set B is a subset of A (is included in A) if every element of B is also an element of A • S is the total space of all elements A B S B A  2. Venniagram

12. Operations (2 of 5) • Equality • Set A equals the set B if and only if (abbreviated iff) every element of A is an element of B and every element of B is an element of A • A = B iff A  B and B  A 2. Venniagram

13. Operations (3 of 5) • Sums and products • The sum, or union, A + B of two sets is a set whose elements are all the elements of A or B or of both • The product , or intersection, AB of two sets is a set consisting all elements that are common to sets A and B AB A B A + B S 2. Venniagram

14. Operations (4 of 5) • Compliment • The compliment A of a set A is defined as a set containing all the elements of S that are not in A A A S 2. Venniagram

15. Operations (5 of 5) • Difference • The difference A - B is a set consisting of all the elements of A that are not in B B A A - B S 2. Venniagram

16. Use for Venn diagrams • A common use of Venn diagrams is to divide the world -- the universe of all elements -- into mutually exclusive sets • However, care should be exercised to not go overboard in searching for design options 2. Venniagram

17. Example not a cost issue cost issue development cost sustaining cost periodic sustaining cost random sustaining cost utilities maintenance Venn diagrams are used to identify places where the design isn’t complete by exposing all options 2. Venniagram

18. 3. Functional flow block diagrams • Definition • Purpose • Functional architecture • Relationship to product architecture • Number • Relationship among blocks • Conventions • Tools • Examples 3. Functional flow block diagrams

19. Definition • A diagram showing the sequential time relationship among functions 3. Functional flow block diagrams

20. Purpose • Used as a stimulus to complete listing what the system is to do • Used to support defining how the system is implemented • Shows functions and activities in the order they can occur 3. Functional flow block diagrams

21. Functional architecture Acquire Train Dispose Level 1 Build Maintain Verify Support Sell off Produce Improve Operate Level 2 Turn on Initialize Load Operate Turn off Test Level 3 Test box 1 Test system Test box 2 3. Functional flow block diagrams

22. Relationship to product architecture FFBDs 1 Level 1 Product FFBDs 2-1 FFBDs 2-2 Level 2 Product 1 Level 2 Product 2 FFBDs 3-1 FFBDs 3-2 Level 3 Product 1 Level 3 Product 2 FFBDs 4-2 FFBDs 4-3 FFBDs 4-1 Level 4 Product 1 Level 4 Product 2 Level 4 Product 3 3. Functional flow block diagrams

23. Number • FFBDs are often done for completeness • There is one set of FFBDs for each product • Each set of FFBDs covers the product and parts of the next lower products • There can be a very large number of blocks in a functional architecture 3. Functional flow block diagrams

24. Relationships among blocks • More than one block within an FFBD may point at the same block in the next lower level • A block may point to more than one block in the next level down • Occasionally, blocks may point at another block across several levels • Most flow is downward, but upward is possible 3. Functional flow block diagrams

25. Conventions • Blocks contain a function number • Each block begins and ends with a reference designator • Reference designator for first block in a string is the source block • An “and” gate indicates parallel functions • An “or” gate indicates alternate functions • Each block is performed by a single actor 3. Functional flow block diagrams

26. Tools • Tools exist for drawing FFBDs • Integrated Definition for Function Modeling (IDEF0) is a more rigorous form of FFBDs, and a tool exist for drawing IDEF0 3. Functional flow block diagrams

27. Example • Problem: Fly across the Bosporus • 3/4 km • year -- 1633 3. Functional flow block diagrams

28. 4. Other stimulation techniques • Present state -- desired state • Duncker diagram • Statement-restatement • Osborn’s checklist for adding new ideas • Random word stimulation From Strategies for Creative Problem Solving by Fogler and LeBlanc 4. Other stimulation techniques

29. Present state/desired state (1 of 4) • Definition -- A method for defining the problem distinctly in a way that suggests solutions • Method • State the present state and the desired state • Reword the present state and the desired state until both states are expressed in the same words, and the desired state is a simple step from the present state 4. Other stimulation techniques

30. Present state/desired state (2 of 4) • Problem: During WW II, many bombers were shot down. Many of the bombers that returned to base were full of holes, and the pattern of holes was similar among bombers • Initial solution: Reinforce the area of holes with more armor 4. Other stimulation techniques

31. Present state/desired state (3 of 4) • Original wording • Present state: Many holes in bombers • Desired state: Fewer bombers lost • Rewording 1 • Present state: Many holes in bombers • Desired state: Fewer holes • Rewording 2 • Present state: Many holes in critical areas • Desired state: Fewer holes in critical areas 4. Other stimulation techniques

32. Present state/desired state (4 of 4) • Suggested solutions: • Protect critical areas • Make areas less critical 4. Other stimulation techniques

33. Duncker diagram (1 of 3) • Definition -- A diagram that suggests solutions based on the present state/desired state • Includes ways to not reach the desired solution 4. Other stimulation techniques

34. Duncker diagram (2 of 3) General solution Achieve desired state OK not to achieve desired state Functional solutions Function 1 Function 1 Function M Function 1 Function 1 Function M Physical solutions Physical 1 Physical 2 Physical N Physical 1 Physical 2 Physical N 4. Other stimulation techniques

35. Duncker diagram (3 of 3) • Problem -- Many holes in critical areas • Reduce number of holes • Reduce the number of holes • Add armor • Reduce number of hits • Increase effectiveness of defensive guns • Increase number of defensive guns • Increase speed • Fly faster • Fly higher • Fly at night • Use fighter escorts 4. Other stimulation techniques

36. Duncker diagram (4 of 5) • Reduce number of holes (continued) • Reduce the number of areas • Consolidate equipment into small area • Reduce the size of areas • Consolidate equipment into fewer areas • Reduce the location of areas • Move equipment to areas that receive fewer holes 4. Other stimulation techniques

37. Duncker diagram (5 of 5) • OK not to reduce number of holes • Survive despite holes • Improve survivability of equipment • Reduce criticality • Add redundancy 4. Other stimulation techniques

38. Statement -- restatement (1 of 5) • Definition -- A problem-solving method in which the problem is restated in different forms a number of times to trigger new ideas 4. Other stimulation techniques

39. Statement -- restatement (2 of 5) • Triggers • 1. Vary the stress pattern on words in the problem statement • 2. Replace words with their explicit definition • 3. Make an opposite statement, change positives to negatives, and vice versa • 4. Change “every” to “some,” “always” to “sometime,” “sometimes” to “never,” and vice versa 4. Other stimulation techniques

40. Statement -- restatement (3 of 5) • Triggers (continued) • 5. Replace persuasive words in the problem statement such as “obviously,” “clearly”, and “certainly,” with the argument it’s supposed to be replacing • 6. Express words in the form of text, an equation, or a picture • Reference --Strategies for Creative Problem Solving 4. Other stimulation techniques

41. Statement -- restatement (4 of 5) • Example -- Many holes in critical areas • Trigger 1 • Many holes in critical areas • Reduce the number of holes • Many holes in critical areas • Reduce the likelihood that a hit will cause a hole • Many holes in critical areas • Make things less critical • Many holes in critical areas • Reduce number of areas 4. Other stimulation techniques

42. Statement -- restatement (5 of 5) • Trigger 2 • Many penetrations through the skin in critical areas • Trigger 3 • Increase number of holes in critical areas • Trigger 4 • All holes in critical areas • Trigger 5 • Obviously we want to reduce the number of holes • Is it OK to have holes?

43. Osborn’s checklist (1 of 5) • Definition -- A method for generating additional ideas from ideas already obtained 4. Other stimulation techniques

44. Osborn’s checklist (2 of 5) • Osborn’s list for creating new ideas • 1. Adapt? • How can this product or idea be used as is? What are other uses it could be adapted to • 2. Modify? • Change the meaning, material, color, shape, odor, etc • 3. Magnify? • Add new ingredient Make longer, stronger, thicker, higher 4. Other stimulation techniques

45. Osborn’s checklist (3 of 5) • Osborn’s list (continued) • 4. Minify? • Spit up. Take something out. Make lighter, lower, shorter • 5. Substitute? • Who else, where else, what else. Other ingredients, material, or approach • 6. Rearrange? • Interchange parts. Other patterns, layouts. Transpose cause and effect. Change positives to negatives. Reverse roles. Turn backwards or upside down. Sort 4. Other stimulation techniques

46. Osborn’s checklist (4 of 5) • Osborn’s list (continued) • Combine • Combine parts. Units, idea. Blend. Compromise. Combine from different categories 4. Other stimulation techniques

47. Osborn’s checklist (5 of 5) • Example • 1. Adapt -- bomber to fighter • 2. Modify -- bottom turret to top • 3. Magnify -- more guns • 4. Minify -- fewer and smaller critical areas • 5. Substitute -- substitute armor for skin • 6. Rearrange -- offset side gunners • 7. Combine -- larger engines 4. Other stimulation techniques

48. Random word stimulation • Definition -- A method for generating ideas when brainstorming is stuck in a rut • Method -- Choose a word at random and see if the word stimulates an idea • Example • Random word -- quack • Quack suggests -- duck • Duck suggests -- goose • Goose suggests -- formation • Formation suggests -- fly in groups 4. Other stimulation techniques

49. 5. Axiomatic design • Introduction • Axioms • Corollaries • Coupling • Examples 5. Axiomatic design

50. Introduction • Introduced by Nam Suh, a professor at MIT in the mid 1980s • Compare designs and provide relative measure of goodness • Doesn’t specify how to design 5. Axiomatic design