Why/When is Taguchi Method Appropriate?

Why/When is Taguchi Method Appropriate? Tip #6 Using Orthogonal Arrays for Generating Balanced Combinations of NoIsE Factors Friday, 25th May 2001

Tip #6 Taguchi Method Using Orthogonal Arrays for Generating Balanced Combinations of NoIsE Factors • In many applications, one can identify several NoIsE factors (with 2- or 3-levels) that could be included during the OA-based experiments • 2 or 3 Noise Factors => use ‘all’ factorial combinations • more than 3 Noise Factors => • ‘all’ factorial combinations are too many • ‘balanced’ combinations using OA  just the right number (between 4 to 9) e.g. L4 (3 NF with 2-levels) 4 combinations L8 (upto 7 NF with 2-levels) 8 combinations L9 (upto 4 NF with 3-levels) 9 combinations

Taguchi Method Using Orthogonal Arrays for Generating Balanced Combinations of NoIsE Factors • In many applications, one can identify several NoIsE factors (with 2- or 3-levels) that could be included during the OA-based experiments • 2 or 3 Noise Factors => use ‘all’ factorial combinations (next slide) 

E1F1 Y11 Y21 Y31 Y41 E1F1 Y61 Y51 Y71 Y81 Y91 E1F2 E1F2 Y62 Y92 Y12 Y42 Y82 Y32 Y72 Y52 Y22 E2F1 Y13 Y23 Y93 Y63 E2F1 Y83 Y53 Y73 Y33 Y43 Y84 Y74 Y94 Y64 E2F2 Y14 Y24 Y44 E2F2 Y34 Y54 7 1 4 2 2 3 3 3 1 1 1 1 1 2 1 1 1 2 2 3 2 1 3 2 2 3 2 5 8 2 2 1 9 2 2 3 6 3 1 3 1 3 3 3 3 (7) Taguchi Method for Q&R : L9 expt. with 2 noise factors L9 expt. with 2 Noise Factors (2-levels each) Control Factors Measurements to Capture Noise Expt.No. A B C D E and F are noise factors with 2 level each ‘all’ 4 combinations are E1F1 , E1F2 , E2F1 and E2F2

Taguchi Method Using Orthogonal Arrays for Generating Balanced Combinations of NoIsE Factors • 3 Noise Factors => • ‘balanced’ combinations using OA  gives just the right number (between 4 to 9) • L4 (3 NF with 2-levels)  4 combinations (next slide) 

Measurements to Capture Noise 1 1 1 1 2 2 1 2 2 2 3 1 1 2 4 2 Y71 Y21 E1F1G1 Y91 Y81 E1F1G1 Y51 Y31 Y41 Y11 Y61 Y72 Y52 Y82 Y92 Y42 Y22 Y12 Y62 Y32 E1F2G2 E1F2G2 E2F1G2 Y13 Y33 Y63 Y23 E2F1G2 Y83 Y43 Y73 Y53 Y93 E2F2G1 E2F2G1 Y34 Y64 Y24 Y84 Y14 Y54 Y74 Y44 Y94 1 4 3 7 2 1 1 2 1 2 1 1 1 3 3 1 2 2 2 3 1 2 3 2 8 2 1 2 5 3 1 3 3 2 1 3 3 1 2 3 3 2 3 9 6 (7) Taguchi Method for Q&R : L9 expt. with 2 noise factors L9 expt. With Noise Array L4 Array # G Control Factors F E Expt.No. A B C D E, F and G are noise factors with 2 level each, 4 combinations as per L4 Array are E1F1G1 , E1F2G2, E2F1G2 and E2F2G1

H 1 2 3 3 1 2 2 3 1 G 1 2 3 2 3 1 3 1 2 F 1 2 3 1 2 3 1 2 3 E 1 1 1 2 2 2 3 3 3 #1 #1 #2 #2 #3 #3 #4 #4 #5 #5 #6 #6 #7 #7 #8 #8 #9 #9 Y11 Y12 Y13 Y14 Y15 Y16 Y17 Y18 Y19 Y21 Y22 Y23 Y24 Y25 Y26 Y27 Y28 Y29 2 2 2 1 1 1 1 3 4 1 1 7 3 3 1 Y31 Y32 Y33 Y34 Y35 Y36 Y37 Y38 Y39 2 3 2 3 1 2 3 2 2 2 5 1 8 2 1 3 2 1 3 2 1 1 3 3 9 3 3 3 6 2 Y41 Y42 Y43 Y44 Y45 Y46 Y47 Y48 Y49 Y51 Y52 Y53 Y54 Y55 Y56 Y57 Y58 Y59 Y61 Y62 Y63 Y64 Y65 Y66 Y67 Y68 Y69 Y71 Y72 Y73 Y74 Y75 Y76 Y77 Y78 Y79 Y81 Y82 Y83 Y84 Y85 Y86 Y87 Y88 Y89 Y91 Y92 Y93 Y94 Y95 Y96 Y97 Y98 Y99 (7) Taguchi Method for Q&R : L9 expt. with 2 noise factors L9 expt.WithNoise Array L9 Array Control Factors Measurements to CaptureNoIsE Expt.No. A B C D E, F, G and H are noise factors with 3 level each, 9 combinations as per L9 Array are used for measurements #1 to #9

Taguchi Method Using Orthogonal Arrays for Generating Balanced Combinations of NoIsE Factors • 3 or more Noise Factors => • ‘balanced’ combinations using OA  gives just the right number (between 4 to 9) • L4 (3 NF with 2-levels) 4 combinations • L8 (upto 7 NF with 2-levels) 8 combinations • L9 (upto 4 NF with 3-levels) 9 combinations Friday, 25th May 2001

Taguchi Method 1st Priority : Variance Reduction2nd Priority : Factor Effects 15.“inner” L9 array with “outer” L4 and L9 NoIsE arrays Taguchi Method “inner” L18 array with “outer” L4 and L9 NoIsE arrays Taguchi Method Why/When is TaguchiMethod not Appropriate? Friday, 3rd Aug 2001 Friday, 27th July 2001 Friday, 20th July 2001 Friday, 13th July 2001 More Tips Links below Tips 12, 11, 10 

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

Taguchi Method Identifies the “right”NoIsEfactor(s) for Tolerance Design Taguchi Method Finds best settings to optimizeTWO 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 More Tips Links below Tips 6, 5, 4 

Taguchi MethodUsing Orthogonal Arrays for Generating Balanced Combinations of NoIsE Factors Taguchi MethodSignal-to-Noise Ratio for Quality Characteristicsapproaching IDEAL value 4. Taguchi Methodimproves " quality “ at all the life stages atthe design stage itself Friday, 25th May 2001 Friday, 18th May 2001 Friday, 11th May 2001 More Tips Links below Tips 3, 2, 1 

3. Taguchi MethodAppropriate forConcurrent Engineering 2. Taguchi Methodcan studyInteraction between Noise Factors and Control Factors 1. Taguchi’sSignal-to-Noise Ratiosare inLog form Friday, 4th May 2001 Friday, 27th April 2001 Friday, 6th April 2001 More Tips Links below

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Why/When is Taguchi Method Appropriate?