Engineering Robust Designs with Six Sigma

Description:

"Dr. Wang's work is of the highest caliber. He has the ability to take very complex subjects and to present them very clearly. He makes excellent use of examples throughout the book."
--Donald W. Sova, Ph.D., Booz Allen Hamilton

"I have not seen a text that provides such broad coverage of the topic. The foremost feature of this is competitive advantage. This product should provide superior utility at a lower cost to both the consumer and to the producer. Competitive advantage is rapidly becoming a necessity to stay in the game."
--Jeffrey B. Lynch, Northrop Grumman Corporation

"Few, if any, other people have the experience in both quality engineering (Six Sigma) and in product engineering that could match Dr. Wang's. A great deal of the unique value of this book is the integration of ideas from these two disciplines."
--Marvin L. Roush, Professor Emeritus, University of Maryland at College Park

Leverage Six Sigma to Transform Product Design and Development

Today's customers demand unprecedented reliability, efficiency, flexibility, and affordability. To deliver products, this robust, quality manufacturing isn't enough; Six Sigma processes must begin in the earliest stages of design. Now, one of the field's leading experts offers the first complete blueprint for implementing Six Sigma product design. John X. Wang has transformed product design at companies ranging from Maytag and Visteon to General Electric. In this book, he illuminates the full spectrum of proven techniques, from Voice-of-Customer (VOC) and Critical-to-Quality (CTQ) to Kano modeling. You'll discover how Six Sigma can bridge critical gaps between research and development, product and process, and how it can help you quickly respond to any change, from new suppliers to emerging customer requirements. Topics covered include

• Starting out: identifying projects, organizing teams, developing VOC models,
• formulating CTQ characteristics
• Creating robust design concepts: principles, practical techniques, and engineering parameters
• Kano modeling: delighting customers and responding to their evolving requirements
• QFD: building a "house of quality" that reflects both spoken and unspoken customer needs
• Failure Mode and Effect Analysis (FMEA): preventing failures, mitigating risks
• Minimizing lifecycle cost through effective tolerance design
• Designing in long-term reliability

If you're an engineer, manager, or quality professional who's ready to drive breakthrough improvements in product design and development, Dr. John X. Wang will guide you, every step of the way, to success.

 

 

Table of Contents:

Preface xiii
About the Author xvii

Chapter 1. Achieving Robust Designs with Six Sigma: Dependable, Reliable, and Affordable 1

1.1 Six Sigma and Robust Design 1

1.2 Identify Project and Organize Team 3

1.3 Develop VOC Models 4

1.4 Formulate Critical-to-Quality Characteristics 6

1.5 Control Energy Transformation for Each CTQ Characteristic 8

1.6 Determine Control and Noise Factors 12

1.7 Assign Control Factors to the Inner Array 15

1.8 Summary and Road Map 20

Bibliography 23

Chapter 2. The Kano Model: Listening to the Voice-of-Customers 25

2.1 How to Make the Customer Happy 26

2.2 Customer Requirements Over Time 32

2.3 Control Factor Levels: Ensure Three Types of Quality 34

2.4 Noise-by-Control Analysis: Making Products More Robust 38

2.5 Variability Reduction 40

2.6 The Outer Array: An Orthogonal Array Specifying Multiple Noises 43

2.7 Selecting Noise Levels 45

2.8 Summary 47

Bibliography 48

Chapter 3. Quality Function Deployment: Building a House of Quality 51

3.1 Market Research and Determining Customers' Needs 52

3.2 Goal Tree: Spelling Out Unspoken Needs 55

3.3 Building a House of Quality 58

3.4 Deploy Quality Through Design of Experiments 63

3.5 Experiments for Deploying Robust Quality Functions 68

3.6 Summary 73

Bibliography 74

Chapter 4. Theory of Inventive Problem Solving: Creating Robust Design Concepts 77

4.1 Contradiction: The Gateway to New Designs 79

4.2 Thirty-Nine Engineering Parameters to Standardize CTQs 80

4.3 Forty Principles to Identify Design Solutions 84

4.4 Calculating the Average of Control Factor Effects 93

4.5 Calculating the Effects of Noise Factors 96

4.6 Noise-by-Control Interaction Effects 99

4.7 Summary 102

Appendix 103

Bibliography 111

Chapter 5. Failure Mode and Effect Analysis: Being Robust to Risk 113

5.1 The Historical Context of FMEA 114

5.2 Using FMEA to Prevent Failure Before Any Harm Is Done 117

5.3 Identifying Functions and Failure Modes 118

5.4 Identifying Effects and Severity 123

5.5 Understanding Causes 127

5.6 Assessing Current Controls 129

5.7 Using FMEA for Risk Management 131

5.8 Summary 134

Bibliography 135

Chapter 6. The P-Diagram: Laying Out a Robust Design Strategy 139

6.1 Experimental Design and the P-Diagram 139

6.2 Quality Loss Function 147

6.3 Noise Factor Management Strategies 150

6.4 Three Phases: From Thought to Things 156

6.5 Summary 159

Bibliography 160

Chapter 7. Parameter Design: Optimizing Control Factor Levels 163

7.1 Identify Project and Team 166

7.2 Formulate Ideal Function 168

7.3 Formulate Dynamic Parameter Design 171

7.4 Assign Control Factors to an Inner Array 174

7.5 Assign Noise Factors and Signal to an Outer Array 178

7.6 Conduct the Experiment and Collect Data 183

7.7 Analyze the Data and Select an Optimal Design 186

7.8 Summary 192

Bibliography 193

Chapter 8. Tolerance Design: Minimizing Life-Cycle Cost 195

8.1 Tolerance Design versus Tolerancing 197

8.2 Reduction in Variability 201

8.3 Tightening Tolerance Selectively to Maximize Quality-versus-Cost Tradeoffs 203

8.4 Quantifying the Quality Loss Function 204

8.5 A Wheatstone Bridge System 210

8.6 Summary 213

Bibliography 216

Chapter 9. Reliability Design: Giving Customers Long-Lasting Satisfaction 219

9.1 Reliability and Six Sigma 220

9.2 Reliability and Stress-Strength Interference 231

9.3 Stress-Strength Interference Sigma Calculations 241

9.4 Summary 248

Bibliography 248

Appendix. The Process Map: Engineering Robust Products with Six Sigma 251

Index 255