Design For Six Sigma

Travis Eck

SelectionConsideration DFSS GB Improvement GB LEAN GB

Complexity Very Complex Moderately Complex Moderately Complex Time Commitment Very High Moderately High Moderately High Training Entire Team – 2

weeks; 2nd week team trains together

One person – 2 weeks, Remaining team – recommended but not required.

One person – 2 weeks, Remaining team – recommended but not required

Certification Entire Team (max. 8) One person – GB One person – GB LEAN

Data Must be quantifiable to ensure new process meets critical to quality factors (CTQ) identified by voice of the customer (VOC)

Current data must be available to demonstrate current as well as improved process performance.

Focus is on streamlining the process; use data to demonstrate current as well as improved process performance.

VOC Extensive Moderate. Used to define CTQ's

Moderate. Used to define CTQ's

Outcome New process Requires business case for Champion support.

Improved process. Requires business case for Champion support.

Streamlined process Requires business case for Champion support.

Outline

Tools for Design

Design- Design failure mode- Effect analysis- Reliability Prediction

Design Development- The Taguchi loss function- Optimizing Reliability

Design Verification- Reliability testing- Measurement system evaluation- Process capability Evaluation

Tools for Process Improvement

Basic tools- Flow Charts- Run Charts- Control Charts- Check Sheets- Histograms- Pareto Diagrams- Cause and Effect Diagrams- Scatter DiagramsOther tools- Kaizen Blitz- Poka-Yoke - Process simulationEngaging the Workforce- Improvement- Skills for team leaders- Skills for team members

Tools for Design

Design failure Mode and effect analysis (DFMEA)

Design-FMEAs should be used throughout the design process - from the preliminary design to when the product goes into production.  Design-FMEAs uncover potential failures associated with the product that could cause product malfunctions, shortened product life, and safety hazards to name a few.

Tools for Design

Reliability Prediction

• The ability to perform over time

• Numerical measurement between 0-1

• Functional failure• Reliability failure

Tools for Design Development

The Taguchi loss function

"a minimal loss at the nominal value, and an ever-increasing loss with departure either way from the nominal value."   - W. Edwards Deming Out of the Crisis. p.141

• Measuring loss • Keeps focus • keep product and process as

close to the nominal value as possible

Tools for Design DevelopmentOptimizing Reliability

• Crucial Steps:Assess process capabilities to achieve critical design parameters and meet CTQ limits

• Optimize design to minimize sensitivity of CTQs to process parameters

• Design for robust performance and reliability

• Error proofing • Establish statistical tolerance • Optimize sigma and cost • Commission and startup

Tools for Design Verification

Reliability Testing

• Life testing• Accelerated life testing• Component Stress testing• Metrology• Accuracy• Precision• Repeatability

Tools for Design Verification

Tools for Design Verification

Process Capability Evaluation

• Where is the process centered?

• How much variability exists in the process?

• Is the performance relative to specifications acceptable?

• What proportion of output will be expected to meet expectations?

• What factors contribute to variability?

Tools for Process Improvement

Tools for Process Improvement

Flow and Run Charts

• Easy to use• Clear Communications• Identifies areas of

opportunities• Familiar in the business

world• Great for comparing data• Good for project

identifications

Basic Tools

Control Charts

Identify variationsPredict when process is out of

controlAnticipates changeTells a story

Check Sheets

Provide clarity of ideasUseful in keep discussions ideas

on targetQuickly createdEasily reorganized

Basic ToolsDaily Defect Rate (Past Due)

0

100

200

300

400

500

600

700

1/27

/06

1/30

/06

1/31

/06

2/1/

06

2/2/

06

2/3/

06

2/6/

06

2/7/

06

2/8/

06

2/9/

06

2/10

/06

2/13

/06

2/14

/06

2/15

/06

2/16

/06

2/17

/06

2/20

/06

2/21

/06

2/22

/06

2/23

/06

2/24

/06

2/27

/06

2/28

/06

3/1/

06

3/2/

06

3/3/

06

3/6/

06

3/7/

06

3/8/

06

3/9/

06

3/10

/06

3/13

/06

3/14

/06

3/15

/06

3/16

/06

3/17

/06

20-M

ar

21-M

ar

22-M

ar

23-M

ar

24-M

ar

27-M

ar

28-M

ar

29-M

ar

30-M

ar

31-M

ar

3-Apr

4-Apr

5-Apr

6-Apr

7-Apr

10-A

pr

11-A

pr

12-A

pr

13-A

pr

14-A

pr

17-A

pr

18-A

pr

19-A

pr

20-A

pr

21-A

pr

24-A

pr

25-A

pr

26-A

pr

27-A

pr

28-A

pr

5/1/

2006

5/2/

2006

5/3/

2006

5/4/

2006

5/5/

2006

5/8/

2006

5/9/

2006

5/10

/2006

5/11

/2006

5/12

/2006

5/15

/2006

5/16

/2006

0%

5%

10%

15%

20%

25%

30%

35%

40%

Project Annual Savings Probability Costs Time, Years PPI

Reduce Inspector calls by 40% $2,040.00 58.17% $10.00 1 118.32

Reduce form corrections by 25% $6,240.00 85.27% $530.00 2 50.19

Increase inspector online acceptence by 30% $21,610.00 61.72% $4,347.00 0.5 61.3

Decrease customer inquiry emails by 50% $36,000.00 54.41% $11,230.00 1.5 116.28

Decrease internal transfers by 60% $6,960.00 53.00% $500.00 0.5 47.2

Increase website performance by 50% $68,250.00 92.30% $14,880.00 0.33 127.87

Remove inspector phoned in results $10,800.00 94.00% $2,200.00 0.3 153.8

Histograms

• Prioritizes opportunities• Provides base for projects• Recognizable

Pareto Diagrams

• Prioritize work

Principle that 80% of deviations are caused by 20% of the process

Basic ToolsDaily Inspections

0100020003000400050006000700080009000

10000

0.00-0.72

0.72-1.44

1.44-2.17

2.17-2.89

2.89-3.61

3.61-4.33

4.33-5.05

5.05-5.77

5.77-6.50

6.50-7.22

Business Days

Cou

nts

Cause and Effect Diagrams

• Also known as the 5 whys• Root Cause Analysis• Structures thoughts• Keeps group on track• Directs improvements to the

right areas

Basic Tools

Author, Page Number, Date

Effect

Category

Category

Category Category Category

Category Category Category

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

cause

Group Activity

Scatter Diagrams

• Help define the correlation between characteristics

• Indicate a cause and

effect relationship

Basic Tools

• Kaizen Blitz

• Poka-Yoke

"The causes of defects lie in worker errors, and defects are the results of neglecting those errors. It follows that mistakes will not turn into defects if worker errors are discovered and eliminated beforehand“ Shingo 1986, p.50

• Process Simulation

Other Tools

• Change the culture to an improvement focus group

• Develop programs that encourage and develop the right skills for team leaders

• Develop training and communication that provide additional skills to all team members

Engaging the workforce

Questions?