Dimensional variation in assembled products directly affects product performance. To reduce dimensional variation, it is necessary that an assembly be robust. A robust assembly is less sensitive to input variation from the product and process components, such as incoming parts, subassemblies, fixtures, and welding guns. In order to effectively understand the sensitivity of an assembly to input variation, an appropriate set of metrics must be defined. In this paper, three product-oriented indices, including pattern sensitivity index, component sensitivity index, and station sensitivity index, are defined. These indices can be utilized to measure the variation influence of a pattern, an individual part, and/or component, and components at a particular station to the dimensional quality of a final assembly. Additionally, the relationships among these sensitivity indices are established. Based on these relationships, the ranges of the sensitivity indices are derived. Finally, a case study of a sheet metal assembly is presented and discussed to illustrate the applicability of these metrics.
1.
Taguchi
, G.
, and Wu
, Y.
, 1979, “Introduction to Off-Line Quality Control
, Central Japan Quality Control Association
, Meieki Nakamura-Ku Magaya, Japan
.2.
Arora
, J. S.
, and Haug
, E. J.
, 1979, “Methods of Design Sensitivity Analysis in Structural Optimization
,” AIAA J.
0001-1452, 17
(9
), pp. 970
–974
.3.
Beltracchi
, T. J.
, and Gabriele
, G. A.
, 1988, “A RQP Based Method for Estimating Parameter Sensitivity Derivatives
,” Proceedings of Design Automation Conference
, ASME
, New York, Vol. 14
, pp. 155
–164
.4.
Phadke
, M. S.
, 1989, Quality Engineering Using Robust Design
, Prentice Hall
, Englewood Cliffs, NJ.5.
Parkinson
, A.
, Sorensen
, C.
, Free
, J.
, and Canfield
, B.
, 1990, “Tolerances and Robustness in Engineering Design Optimization
,” Proceedings of 1990 ASME Design Automation Conference
, Sept., Chicago, ASME
, New York, Vol. 2
, pp. 121
–128
.6.
Parkinson
, A.
, Sorensen
, C.
, and Pourhassan
, N.
, 1993, “A General Approach for Robust Optimal Design
,” ASME J. Mech. Des.
1050-0472, 115
, pp. 74
–80
.7.
Parkinson
, A.
, 1995, “Robust Mechanical Design Using Engineering Models
,” ASME J. Mech. Des.
1050-0472, 117
, pp. 48
–54
.8.
Chen
, W.
, Allen
, J. K.
, Tsui
, K.-L.
, and Mistree
, F.
, 1996, “A Procedure for Robust Design: Minimizing Variations Caused by Noise Factors and Control Factors
,” ASME J. Mech. Des.
1050-0472, 118
, pp. 478
–485
.9.
Ting
, K.
, and Long
, Y.
, 1996, “Performance Quality and Tolerance Sensitivity of Mechanisms
,” ASME J. Mech. Des.
1050-0472, 118
(1
), pp. 144
–150
.10.
Cai
, W.
, Hu
, S. J.
, and Yuan
, J. X.
, 1997, “A Variational Method of Robust Fixture Configuration Design for 3-D Workpieces
,” ASME J. Manuf. Sci. Eng.
1087-1357, 119
, pp. 593
–602
.11.
Gao
, J.
, Chase
, K. W.
, and Magleby
, S. P.
, “Global Coordinate Method for Determining Sensitivity in Assembly Tolerance Analysis,” http://adcats.et.byu.edu/WWW/Publication/98-3/Paper6_2col_6=29=98.htmlhttp://adcats.et.byu.edu/WWW/Publication/98-3/Paper6_2col_6=29=98.html12.
Söderberg
, R.
, and Lindkvist
, L.
, 1999, “Computer Aided Assembly Robustness Evaluation
,” J. Eng. Design
0954-4828, 10
(2
), pp. 165
–181
.13.
Thornton
, A. C.
, 2000, “Quantitative Selection of Variation Reduction Plans
,” ASME J. Mech. Des.
1050-0472, 122
, pp. 185
–193
.14.
Ding
, Y.
, Ceglarek
, D.
, and Shi
, J.
, 2002, “Design Evaluation of Multi-Station Assembly Processes by Using State Space Approach
,” ASME J. Mech. Des.
1050-0472, 124
(3
), pp. 408
–418
.15.
Hu
, S. J.
, Webbink
, R.
, Lee
, J.
, and Long
, Y.
, 2003, “Robustness Evaluation for Compliant Assembly Systems
,” ASME J. Mech. Des.
1050-0472, 125
(2
), pp. 262
–267
.16.
Caro
, S.
, Bennis
, F.
, and Wenger
, P.
, 2005, “Tolerance Synthesis of Mechanisms: A Robust Design Approach
,” ASME J. Mech. Des.
1050-0472, 127
(1
), pp. 86
–94
.17.
Lee
, B.
, and Saitou
, K.
, 2006, “Three-Dimensional Assembly Synthesis for Robust Dimensional Integrity Based on Screw Theory
,” ASME J. Mech. Des.
1050-0472, 128
(1
), pp. 243
–251
.18.
Lindvist
, L.
, and Söderberg
, R.
, 2003, “Computer Aided Tolerance Chain and Sensitvity Analysis
,” J. Eng. Design
0954-4828, 14
(1
), pp. 17
–39
.19.
Ceglarek
, D.
, and Shi
, J.
, 1998, “Variation Design Evaluation of Sheet Metal Joints for Dimensional Integrity
,” ASME J. Manuf. Sci. Eng.
1087-1357, 120
, pp. 452
–460
.20.
Wang
, M. Y.
, 1999, “An Optimum Design Approach to Fixture Synthesis for 3D Workpieces
,” Trans. North Am. Manuf. Res. Inst. SME
1047-3025, XXVII
, pp. 209
–214
.21.
Liu
, S. C.
, Hu
, S. J.
, and Woo
, T. C.
, 1996, “Tolerance Analysis for Sheet Metal Assemblies
,” ASME J. Mech. Des.
1050-0472, 118
, pp. 62
–67
.22.
Liu
, S. C.
, and Hu
, S. J.
, 1997, “Variation Simulation for Deformable Sheet Metal Assemblies Using Finite Element Methods
,” ASME J. Manuf. Sci. Eng.
1087-1357, 119
, pp. 368
–374
.23.
Camelio
, J.
, Hu
, S. J.
, and Ceglarek
, D.
, 2003, “Modeling Variation Propagation of Multi-Station Assembly Systems With Compliant Parts
,” ASME J. Mech. Des.
1050-0472, 125
(4
), pp. 673
–681
.24.
Hu
, S. J.
, and Wu
, S. M.
, 1992, “Identifying Root Causes of Variation in Automobile Body Assembly Using Principal Component Analysis
,” Trans. North Am. Manuf. Res. Inst. SME
1047-3025, 20
, pp. 311
–316
.25.
Ceglarek
, D.
, and Shi
, J.
, 1996, “Fixture Failure Diagnosis for Autobody Assembly Using Pattern Recognition
,” ASME J. Eng. Ind.
0022-0817, 118
, pp. 55
–66
.26.
Camelio
, J.
, and Hu
, S. J.
, 2004, “Multiple Fault Diagnosis for Sheet Metal Fixtures Using Designated Component Analysis
,” ASME J. Manuf. Sci. Eng.
1087-1357, 126
(1
), pp. 91
–97
.27.
Camelio
, J.
, Hu
, S. J.
, and Marin
, P. S.
, 2004, “Compliant Assembly Variation Analysis Using Geometric Covariance
,” ASME J. Manuf. Sci. Eng.
1087-1357, 126
(2
), pp. 355
–360
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