1. Chapter 12- Quality By Design
Introduction
Concurrent Engineering
Life-Cycle Costs and Engineering Changes
Quality Function Deployment
Design for Manufacture and Assembly
Taguchi Methods
Conclusion

2. Metrics for Design Quality
Percent of revenue from new products or services
Percent of products capturing 50% or more of the market
Percent of process initiatives yielding a 50% or more improvement in effectiveness
Percent of suppliers engaged in collaborative design

3. Concurrent Engineering
The Design Process
Life-Cycle Costs and Engineering Changes
What Concurrent Engineering Teams Do
Benefits of Concurrent Engineering
Concurrent Engineering Team Organization

4. What Concurrent Engineering Teams Do
Determine the overall character of the product, its design, and method of manufacture.
Perform product functional analysis.
Explore ways to improve producibility and usability.
Design a process for product assembly and production control, and design the parts of the product to be compatible with the assembly process.
Design the manufacturing processes for the product.

5. Benefits of Concurrent Engineering
Helps to understand the requirements of customers so that a better product acceptable to customers may be designed and made.
Product development time is reduced since design and process planning activities are completed simultaneously.
Design trade-offs, for example, between product features and production capabilities can be easily be facilitated with a view to improve the design.

6. Life-Cycle Costs and Engineering Changes
- Costs incurred from cradle to grave
- About 80% of product costs are committed in the design and development phase of a product.
- Consequently, it is important to avoid mistakes early on in the design process.
- The design and redesign process will require numerous engineering change orders that could be time consuming and lengthy. -

7. Fault Tree for Potato Chips

8. FMEA for Potato Chips Stale
FAILURE
MODE CAUSE OF FAILURE EFFECT OF FAILURE CORRECTIVE ACTION
Stale
Low moisture content, expired shelf life, poor packaging
Tastes bad, won’t crunch, thrown out, lost sales
Add m cure longer, better package seal, shorter shelf life
Broken
Too thin, too brittle, rough handling, rough use, poor packaging
Can’t dip, poor display, injures mouth, chocking, perceived as old, lost sales
Change recipe, change process, change packaging
Too Salty
Outdated receipt, process not in control, uneven distribution of salt
Eat less, drink more, health hazard, lost sales
Experiment with recipe, experiment with process, introduce low salt version

9. Value Analysis (Value Engineering)
Ratio of value / cost
Assessment of value :
1. Can we do without it?
2. Does it do more than is required?
3. Does it cost more than it is worth?
4. Can something else do a better job
5. Can it be made by less costly method, tools, material?
6. Can it be made cheaper, better or faster by someone else?

10. Design for Environment
Design from recycled material
Use materials which can be recycled
Design for ease of repair
Minimize packaging
Minimize material & energy used during manufacture, consumption & disposal

11. Design for Environment

12. Quality Function Deployment (QFD)
Developed by Mitsubishi’s Kobe Shipyard in 1972 and was adopted by Toyota 1978
QFD is being used by numerous US companies now
- This is a planning, communication, and documentation technique used to resolve design problems
- Translates the “voice of the customer” into technical design requirements
- Displays requirements in matrix diagrams
- First matrix called “house of quality”
- Series of connected houses

13. Design characteristics Customer requirements Competitive assessment
House of Quality
Correlation matrix
Design characteristics
Customer requirements
Target values
Relationship matrix
Competitive assessment
Importance 1 2 3 4 5 6

14. Competitive Assessment
House of Quality
Figure 3.8
Irons well
Easy and safe to use
Competitive Assessment
Customer Requirements
Presses quickly 9 B A X
Removes wrinkles 8 AB X
Doesn’t stick to fabric 6 X BA
Provides enough steam AB X
Doesn’t spot fabric 6 X AB
Doesn’t scorch fabric 9 A XB
Heats quickly 6 X B A
Automatic shut-off ABX
Quick cool-down 3 X A B
Doesn’t break when dropped 5 AB X
Doesn’t burn when touched 5 AB X
Not too heavy 8 X A B

15. House of Quality Customer Requirements Presses quickly - - + + + -
Time required to reach 450º F
Time to go from 450º to 100º
Protective cover for soleplate
Material used in soleplate
Flow of water from holes
Energy needed to press
Thickness of soleplate
Automatic shutoff
Size of soleplate
Number of holes
Weight of iron
Size of holes
Customer Requirements
Presses quickly
Removes wrinkles
Doesn’t stick to fabric
Provides enough steam
Doesn’t spot fabric
Doesn’t scorch fabric
Heats quickly
Automatic shut-off
Quick cool-down
Doesn’t break when dropped
Doesn’t burn when touched
Not too heavy
Irons well
Easy and safe to use

16. House of Quality + - Figure 3.10 Protective cover for soleplate
Time to go from 450º to 100º
Time required to reach 450º
Material used in soleplate
Flow of water from holes
Energy needed to press
Thickness of soleplate
Automatic shutoff
Size of soleplate
Number of holes
Weight of iron
Size of holes - +

17. Design For Manufacturing and Assembly
Design Axioms
DFM Guide Lines
DFA Principles
Fully Exploiting DFMA

18. Taguchi Methods Robust Design Taguchi Approach to Design
Planned Experimentation
Design of Experiments
DOE and DFMA for Process Improvement
Orthogonal Arrays
Quality Loss
Criticism of Taguchi