Why/When is Taguchi Method Appropriate? Tip #7 Taguchi Method : When to Select a ‘larger’ OA to perform “Factorial Experiments” Friday, 1st June 2001

Tip #7 Taguchi Method : When to Select a ‘larger’ OA to perform “Factorial Experiments” We always ‘think’ about ‘reducing’ the number of experiments (to minimize the ‘resources’ – equipment, materials, manpower and time) However, doing ALL / Factorial experiments is a good idea if Conducting experiments is ‘cheap’ but measurements are ‘expensive’ The experimental facility will NOT be available later to conduct the ‘verification’ experiment We do NOT wish to conduct separate experiments for studying interactions between Control Factors

Taguchi Method : When to perform ALL / “Factorial Experiments” Conducting ALL / Factorial experiments is a good idea if Conducting experiments is ‘cheap’ (and in-house) but measurements are ‘expensive’ (and elsewhere) When an apparatus is fully set-up, it may be rather easy to conduct the experiments quickly (if we are not hampered by measurements in between the experiments) Just collect all samples (that have ‘captured’ the effects of NoIsE factors) Send samples (elsewhere) for measurements (make sure that these will capture the effects of NoIsE)

Taguchi Method : When to perform ALL / “Factorial Experiments” Conducting ALL / Factorial experiments is a good idea if The experimental facility will NOT be available LATER to conduct the ‘verification’ experiment A typical case when experiments are done On Production equipment On Borrowed equipment In presence of visiting ‘experts’

Taguchi Method : When to perform ALL / “Factorial Experiments” Conducting ALL / Factorial experiments is a good idea if We do NOT wish to conduct separate experiments for studying interactions between Control Factors Analyze without considering interactions, Predict best combinations of control factors as well as Best results. Check this out – we already HAVE the results of the best experiment If the results do not match, Evaluate the “key” interactions – again check results If the results ‘still’ do not match, Evaluate “all” interactions – again check results

Control Factors and Levels Factorial Combinations Taguchi Method : How to Select a ‘larger’ OA to perform “Factorial Experiments” Control Factors and Levels Factorial Combinations Suitable OA 2 CF / 2-levels 4 L4 3 CF / 2-levels 8 L8 4 CF / 2-levels 16 L16 5 CF / 2-levels 32 L32

Control Factors and Levels Factorial Combinations Taguchi Method : How to Select a ‘larger’ OA to perform “Factorial Experiments” Control Factors and Levels Factorial Combinations Suitable OA 2 CF / 3-levels 9 L9 1 CF / 2-levels 18 L18 3 CF / 3-levels 27 L27 54 L54

Earlier Tips Links below Friday, 27th July 2001 Friday, 20th July 2001 Friday, 13th July 2001 Taguchi Method “inner” L9 array with “outer” L4 and L9 NoIsE arrays “inner” L18 array with “outer” L4 and L9 NoIsE arrays Taguchi Method Why/When is Taguchi Method not Appropriate? Tips 12, 11, 10 

Earlier Tips Links below Friday, 6th July 2001 Friday, 29th June 2001 Friday, 22nd June 2001 Taguchi Method “inner” L8 array with “outer” L4 and L9 NoIsE arrays Useful at ALL Life-stages of a Process or Product Performs Process “centering” or “fine tuning” Tips 9, 8, 7 

Earlier Tips Links below Taguchi Method Identifies the “right” NoIsE factor(s) for Tolerance Design Taguchi Method Finds best settings to optimize TWO quality characteristics Simultaneously 7. Taguchi Method When to select a ‘Larger’ OA to perform “Factorial Experiments” Friday, 15th June 2001 Friday, 8th June 2001 Friday, 1st June 2001 Tips 6, 5, 4 

Earlier Tips Links below Friday, 25th May 2001 Friday, 18th May 2001 Friday, 11th May 2001 Taguchi Method Using Orthogonal Arrays for Generating Balanced Combinations of NoIsE Factors Taguchi Method Signal-to-Noise Ratio for Quality Characteristics approaching IDEAL value 4. Taguchi Method improves " quality “ at all the life stages at the design stage itself Tips 3, 2, 1 

Earlier Tips Links below Friday, 4th May 2001 Friday, 27th April 2001 Friday, 6th April 2001 3. Taguchi Method Appropriate for Concurrent Engineering 2. Taguchi Method can study Interaction between Noise Factors and Control Factors 1. Taguchi’s Signal-to-Noise Ratios are in Log form

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