Study On Axiomatic Design For Six Sigma

During the implementation of Design for Six Sigma (DFSS), the quality of products is influenced by two major design weaknesses, i.e., conceptual weakness due to violating design principles and operational weakness due to lack of robustness in the use environment. The operational weaknesses can be lessened or avoided by reducing variation. Robust Design is thus employed to improve product quality through reducing variation to bring along product functionality during design. However, conceptual weaknesses are usually overlooked during product development as a result of lack of a systematic design approach for seeking ideal solutions.Therefore, the theory of Axiomatic Design is incorporated herein into DFSS, and Axiomatic Design for Six Sigma is put forward and researched deeply as follows: Firstly, some design methods and theories are described such as DFSS, Axiomatic Design, TRIZ, QFD and Robust Design, etc. Moreover, Axiomatic Design for Six Sigma (ADFSS) is put forward. The ADFSS approach is based on Axiomatic Design which is integrated with design and quality methods such as TRIZ, QFD, VA/VE, Robust Design, FMEA, DFA, DFM and the like, and merged into the philosophy of Six Sigma.Thereafter, the key techniques are studied and applied including decoupling of Axiomatic Design for Six Sigma, Axiomatic Design for Six Sigma based on TRIZ, QFD and Robustness. That is, a common method for decoupling of Axiomatic Design for Six Sigma is put forward and a method incorporating separation algorithm, AHP and shortest path is developed to improve coupling of design of a complicated system. Axiomatic Design for Six Sigma based on TRIZ is provided through analyzing the internal relationship between TRIZ and AD. Analyses of ideal solution and S curve are conducted and the evolution route of products is predicted. At the meantime, inventive principle and separation principle are utilized to solve the problems of conflict and constrains during design to realize uncoupled design of products. With regard to the problems occurred in the application of QFD, a model of Axiomatic Design for Six Sigma based on QFD is established to shorten the cycle of product development and avoid loss of information on customers needs. To reduce or avoid operational weaknesses during design, the concept of robustness is utilized in Axiomatic Design of Six Sigma. Design parameters are optimized with DOE and Taguchi methods, and with the quality loss of function requirements and control cost of design parameters considered, a nonlinear mathematic model for optimizing tolerance is established based on cost-to-quality to eliminate deviation, reduce variance and distribute tolerance of design parameters appropriately, which make the function requirements of products really meet the needs of customers from the beginning of design and reach the level of Six Sigma.Finally, a passive filter of a strain measurement system is designed with the approach of Axiomatic Design for Six Sigma. The result shows that the design structure is simplified and the level of Six Sigma is reached just at the beginning of the design of function requirements with optimized design parameters, less process variation, lower cost, and conceptual and operational weakness during design being avoided.