© 2009 Factory Strategies Group LLC. All rights reserved.

Design of ExperimentsQuality Series

(Sample Slides)

2© 2009 Factory Strategies Group LLC. All rights reserved.© 2009 Factory Strategies Group LLC. All rights reserved.

Outline

• What is Design of Experiments?• Method▫ Step 1: Model Variables▫ Step 2: Set Variable Targets▫ Step 3: Experimental Plan▫ Step 4: Testing▫ Step 4: Analysis

• Effects, Replicates & Interactions

3© 2009 Factory Strategies Group LLC. All rights reserved.© 2009 Factory Strategies Group LLC. All rights reserved.

DOE Goal

• Overall goal:▫ To model a performance parameter (i.e., a physical

phenomenon) as a function of design variables (i.e., things we can control about the design)

• Our approach:▫ Follow the DOE methodology

4© 2009 Factory Strategies Group LLC. All rights reserved.© 2009 Factory Strategies Group LLC. All rights reserved.

Step 5: Analysis

• Determine ß coefficients▫ Regression analysis may be used (spreadsheets)

• ßs can be defined in terms of the effect a variable xi has on the perf. parameter

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5© 2009 Factory Strategies Group LLC. All rights reserved.© 2009 Factory Strategies Group LLC. All rights reserved.

Using the Effects

• From a response diagram point of view:▫ Plot values of y vs. xi(-) and xi(+)

Important DV DV has no effect on perf.