Can Design Be More Creative?

Transcription

1 Can Design Be More Creative? Dr. WJ (Chris) Zhang Professor University of Saskatchewan, Canada

2 Outline 1. System and design: brief overview 2. Science-based design process 3. Science-based designer s cognitive process 4. Summary

3 System and Design 1. A system is a set of elements that are connected 2. An element may further be decomposed into smaller elements; in this case, the element may be called subsystem 3. Design is a decision-making process starting from requirements to system structures

4 System and Design 4. Requirement consists of functional (F) requirement and constraint (C) requirement FR: you must achieve it; e.g., a device to realize the conversion from rotation to translation. CR: you achieve it as possible as you can but not necessary in the sense that if you fail to achieve it, you still have a design that works; e.g., to design a device as cheap as possible or as light as possible. Often when you only have one design, there is no sense to meet any CR but if you have two designs, then you compare them in terms of CR.

5 System and Design Is there any principle, guideline, theory, methodology for a design process that may lead to more innovative design?

6 Science-based Design Process 1. General design process 2. Design theory and methodology 3. Design modeling and optimization Innovative and Creative Design

7 General design process Conceptual design Embodiment design Detailed design

8 Conceptual design Develop technical specification. Technical specification: a document of customer s requirement in the technical term. Example Customer s requirement: Need a drill to penetrate common steel Technical specification: Be able to penetrate into the material with HRC>30

9 Conceptual design Develop solution principle What is solution principle: solution versus solution principle Example Requirement: Rotation to translation Solution principle: - Crank-slider - Rack-and-pinion Remark: for machine design, it refers to kinematic diagram (dimension is given)

10 Embodiment Design Develop a physical entity that realize the solution principle with temporal and spatial characterization Example (Crank-slider) Requirement: FR: To materialize a crank-slider kinematic linkage for load of 50 KN CR: To make device as light as possible

11 Embodiment Design Requirement: FR: To materialize a crank-slider kinematic linkage for load of 50 KN CR: To make device as light as possible Embodiment crankslider linkage:

12 Detailed Design Develop a complete specification for each individual component ready for manufacturing Requirement: FR: To specify geometrical details ready for manufacturing CR: To be easy for manufacturing and assembly Detailed piston component ready for manufacturing

13 Science-based Design Process 1. General design process 2. Design theory and methodology 3. Design modeling and optimization Innovative and Creative Design

14 Design theory and methodology Design Axiom 1: Making what to do and how to do separately. In particular while describing what it is, not be affected by how to realize it Example (Rotation to translation) Requirement statement: When a rotary motor turns, it connects with a rod which further transfers motion to a slider to realize a translation. The above statement has violated Design Axiom 1

15 Simplicity Complexity Design theory and methodology Design Axiom 2: Divide and conquer Problem -0 Problem -1.1 Problem -1.2 Problem -2.1 Problem -2.2

16 Design Axiom 2: Divide and conquer Requirement: hold hot (~100 o C) water with hand Hold hot water Grasp water 16 Hold normal water Resist heat exchange

17 Grasp water Resist heat exchange Ceramic material Hold normal water 17

18 Design theory and methodology Design Axiom 3: Making functional independency (Suh, 1990) Hinge FR1=Provide access to items stored in the refrigerator FR2=Minimize energy loss 18

19 Design Axiom 3: Making functional independency (Suh, 1990) S1 =Horizontally hung door Hinge FR1=Provide access to items stored in the refrigerator FR2=Minimize energy loss S1=Vertically hung door 19 S2=Thermal insulation material in the door

20 Design theory and methodology Design Axiom 4: Generalization of design Generic design problem Other design problems along with their solutions Current design problem A solution to the current design problem Remark: The above process is in fact an analogy process

21 Science-based Design Process 1. General design process 2. Design theory and methodology 3. Design modeling and optimization Innovative and Creative Design

22 Design modeling and optimization 1. Mathematical model for design objects at a different level (conceptual object, embodiment object, detailed object) 2. Variables defined for structural features, and mathematical relations defined for the whole structure along with its behavior 3. Varying of the variables to seek the best behavior

23 Outline 1. System and design: brief overview 2. Science-based design process 3. Science-based designer s cognitive process 4. Summary

24 Science-based designer s cognitive process 1. Team-based brain storm and white-box communication 2. Diversification in team composition and in task management 3. Confidence 4. Removal of unnecessary constraints

25 Summary 1. Design is a marriage of human designers and science-based processes 2. Science-based processes are: general design process, design theory and methodology, and modeling and optimization 3. Design theory and methodology has four axioms 4. Designer s cognitive process includes four guidelines