Six sigma design method
US006675135B1
(12) United States Patent
(10) Patent N0.: (45) Date of Patent:
Murray et al.
(54) SIX SIGMA DESIGN METHOD
US 6,675,135 B1 Jan. 6, 2004
Smith, “Six—Sigma Design”, IEEE Spectrum, vol. 30 Issue
9, pp. 43—47 (Sep. 1993).*
(75) Inventors: Jonathan A. Murray, Sussex, WI
LantZy, “Application of Statistical Process Control to the Software Process”, ACM Proceedings of the 9th Washington Ada Symposium on Ada, pp. 113—123 (1992).*
(US); J e?'rey R. Immelt, PeWaukee, WI (US); William A. Berezowitz,
Green?eld, WI (US) (73) Assignee: GE Medical Systems Global
* cited by examiner
Technology Company, LLC, Waukesha, WI (US) *
N ot1ce: '
patent is extended or adjusted under 35
Primary Examiner—Samuel Broda (74) Attorney, A gent, or Firm—Quarles & Brady, LLP; Carl
USC 154(b) by 0 days.
Horton
s u bj ect to an yd'1sc 1 a1mer, ' t h e term 0 r t h'is
(21) Appl. NO.Z 09/390,417
(57)
(22) Filed?
A method to be used during a product development proce
(51)
(52) (58)
SeP- 3, 1999
ABSTRACT
Int. Cl.7 ......................... .. G06F 17/10; G06F 7/60;
dure wherein the procedure includes a Series of Consecutive
G061: 101/00
development phases and the product includes at least tWo
US. Cl. ............................... .. 703/2; 703/1; 700/95; 700/109; 702/179 Field of Search ............... .. 703/1—2; 702/179—181;
critical to quality Characteristics (CTQs)- The method is for generating a con?dence matrix Which can be used to increase a product sigma through product design. A user
700/95—97> 108—110
initially provides product limits and thereafter provides
(56)
References Cited
additional development information during each consecu tive development phase. During at least tWo of the devel opment phases and for each CTQ, development information
U-S~ PATENT DOCUMENTS 6,253,115 B1 * 6/2001 Martin et a1. ............... .. 700/97 6,301,516 B1 * 10/2001 Ostrowski et al. ........ .. 700/109
is used to determine a quality factor Which is indicative of the probability that the product Will be Within the speci?ed
i Z: 2% ~~~~~~~~~~~~~~~~~~ ~~ 703/1 6:473:72O B1 * 100002 Hampsoh ' ' ‘502/182
limits. Also, for each CTQ, a con?dence factor is identi?ed WhlCh is indicative of the probability that the quality factor is accurate. Then, quality factors, CTQs and con?dence
OTHER PUBLICATIONS
Harrold, “Designing for Six Sigma Capability”, Control
factors are arranged such that the CTQs and factors are correlated.
Engineering, vol. 46 Issue 1, pp. 62—64, 66, 68, and 70 (Jan.
33 Claims, 4 Drawing Sheets
1999).*
RECEIVE DEVELOPMENT
INFO
'\ 220
I DETERMINE QUALITY FACTORS
\ 222
IDENTIFY CONFIDENCE FACTORS \ 224
I ARRANGE CTQS, QUALITY & CONFID. FACTORS \226
ANALYZE
\228
U.S. Patent
Jan. 6, 2004
Sheet 1 0f4
US 6,675,135 B1
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U.S. Patent
Jan. 6, 2004
Sheet 2 0f4
PREDICTION INTERvAL
IDENTIFY | ALLOCATE | SPECIFY
Z
MEASURE |
PREDICT
CONTROL
( START ) RECEIVE DEVELOPMENT
INFO
\220
DETERMINE QUALITY
FACTORS
\222
IDENTIFY CONFIDENCE
FACTORS
\224
ARRANGE CTQS, QUALITY & CONFID. FACTORS \226
ANALYZE
US 6,675,135 B1
\ 228
ACTUAL
U.S. Patent
Jan. 6, 2004
US 6,675,135 B1
Sheet 3 0f 4
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U.S. Patent
Jan. 6, 2004
Sheet 4 0f4
US 6,675,135 B1
FIG. 5 102 110 >60
Q ALLOCATED
E| PREDICTED
D MEASURED
[[1] CONTROLLED
50-60
ZSTLEVEL
40- 50
30-40
(12) United States Patent
(10) Patent N0.: (45) Date of Patent:
Murray et al.
(54) SIX SIGMA DESIGN METHOD
US 6,675,135 B1 Jan. 6, 2004
Smith, “Six—Sigma Design”, IEEE Spectrum, vol. 30 Issue
9, pp. 43—47 (Sep. 1993).*
(75) Inventors: Jonathan A. Murray, Sussex, WI
LantZy, “Application of Statistical Process Control to the Software Process”, ACM Proceedings of the 9th Washington Ada Symposium on Ada, pp. 113—123 (1992).*
(US); J e?'rey R. Immelt, PeWaukee, WI (US); William A. Berezowitz,
Green?eld, WI (US) (73) Assignee: GE Medical Systems Global
* cited by examiner
Technology Company, LLC, Waukesha, WI (US) *
N ot1ce: '
patent is extended or adjusted under 35
Primary Examiner—Samuel Broda (74) Attorney, A gent, or Firm—Quarles & Brady, LLP; Carl
USC 154(b) by 0 days.
Horton
s u bj ect to an yd'1sc 1 a1mer, ' t h e term 0 r t h'is
(21) Appl. NO.Z 09/390,417
(57)
(22) Filed?
A method to be used during a product development proce
(51)
(52) (58)
SeP- 3, 1999
ABSTRACT
Int. Cl.7 ......................... .. G06F 17/10; G06F 7/60;
dure wherein the procedure includes a Series of Consecutive
G061: 101/00
development phases and the product includes at least tWo
US. Cl. ............................... .. 703/2; 703/1; 700/95; 700/109; 702/179 Field of Search ............... .. 703/1—2; 702/179—181;
critical to quality Characteristics (CTQs)- The method is for generating a con?dence matrix Which can be used to increase a product sigma through product design. A user
700/95—97> 108—110
initially provides product limits and thereafter provides
(56)
References Cited
additional development information during each consecu tive development phase. During at least tWo of the devel opment phases and for each CTQ, development information
U-S~ PATENT DOCUMENTS 6,253,115 B1 * 6/2001 Martin et a1. ............... .. 700/97 6,301,516 B1 * 10/2001 Ostrowski et al. ........ .. 700/109
is used to determine a quality factor Which is indicative of the probability that the product Will be Within the speci?ed
i Z: 2% ~~~~~~~~~~~~~~~~~~ ~~ 703/1 6:473:72O B1 * 100002 Hampsoh ' ' ‘502/182
limits. Also, for each CTQ, a con?dence factor is identi?ed WhlCh is indicative of the probability that the quality factor is accurate. Then, quality factors, CTQs and con?dence
OTHER PUBLICATIONS
Harrold, “Designing for Six Sigma Capability”, Control
factors are arranged such that the CTQs and factors are correlated.
Engineering, vol. 46 Issue 1, pp. 62—64, 66, 68, and 70 (Jan.
33 Claims, 4 Drawing Sheets
1999).*
RECEIVE DEVELOPMENT
INFO
'\ 220
I DETERMINE QUALITY FACTORS
\ 222
IDENTIFY CONFIDENCE FACTORS \ 224
I ARRANGE CTQS, QUALITY & CONFID. FACTORS \226
ANALYZE
\228
U.S. Patent
Jan. 6, 2004
Sheet 1 0f4
US 6,675,135 B1
[10 16
17
\
) | —l
_>
/
|
15 20
14
12
1s
\
\. égal
I
__
L2
‘
LL5
L3
L4 L1
22
7
IDENTIFY
-/24
SPECIFY
~/ 26
ALLOCATE
—/ 28
\
30 PREDICT
IMPROVE
ANALYZE
MEASURE
\32 CONTROL
/\_, 34
U.S. Patent
Jan. 6, 2004
Sheet 2 0f4
PREDICTION INTERvAL
IDENTIFY | ALLOCATE | SPECIFY
Z
MEASURE |
PREDICT
CONTROL
( START ) RECEIVE DEVELOPMENT
INFO
\220
DETERMINE QUALITY
FACTORS
\222
IDENTIFY CONFIDENCE
FACTORS
\224
ARRANGE CTQS, QUALITY & CONFID. FACTORS \226
ANALYZE
US 6,675,135 B1
\ 228
ACTUAL
U.S. Patent
Jan. 6, 2004
US 6,675,135 B1
Sheet 3 0f 4
#3
§—\ 60/ k0
"2| 6 MNHHH lHNNv-AMHHHNHHHNN EN NEN mEN w EN EN 5N EN mmN
20. wo ,
ZOCQEM
Em2E2 4
mm
6. 6
/
mm
(om
.wI w
/
Win53
8% :2: mod m w.
2590 $0.60 EQGE $ 5 2 . 4 1 86 MQE
OR
J
/
ow asSE3 /505
HI
mm
152m: 10.50 EQGE 152m: ES /1m 152m: @30 EDGE
1512m:
N m w m
2,
“Eu
QH2z38m6
N
8250 L
U.S. Patent
Jan. 6, 2004
Sheet 4 0f4
US 6,675,135 B1
FIG. 5 102 110 >60
Q ALLOCATED
E| PREDICTED
D MEASURED
[[1] CONTROLLED
50-60
ZSTLEVEL
40- 50
30-40
