Six Sigma

© American Society For Engineering Management Conference Proceedings, 14-17 October 2009.

Systems Approach to Problem Solving using Six Sigma
Ma. del Carmen Temblador Perez. MSc., ME. Tecnologico de Monterrey Mario G. Beruvides, PhD., P.E. Texas Tech University

Abstract Six Sigma (SS) is a methodology used to tackle, in most cases, manufacturing problems, even though it has beensuccessfully used in the service sector and support systems. DMAIC methodology (also known as SS) stands for Define, Measure, Analysis, Improvement and Control, is a problem solving process with a major restriction: it informs on what to do, but not how to do it. In spite of different approaches that involve SS such as Design for Six Sigma (DFSS), Six Sigma Transactional (SST) or more recently Lean SixSigma (LSS) as an attempt to integrate critical elements to make this methodology more applicable, and thus, prolong its cycle-life, the problem is still present. What remains to be solved is how to integrate customer’s needs and company’s defined strategies and apply this integration to the selection of SS projects. The objective of this paper is to integrate systems approach concepts into DMAICmethodology to improve the efficacy and efficiency of SS projects by defining the major deliverables at each stage as well as explaining the need to create a strategic approach to reproduce successful projects (R-DMAIC-R). Key Terms Six Sigma, systems approach, R-DMAIC-R, problem solving. Introduction Systems approach is oriented to help the problem solving processes, including design and control(Kirk 1995) and is especially valuable in complex systems where the number of elements and interactions among those elements are significantly bigger. Six Sigma (SS), on the other hand, is a methodology oriented to reduce variability and decrease costs through a clearlydefined process called DMAIC (Define, Measure, Analyze, Improvement, and Control). Some variations were made to the DMAIC processin order to integrate the organizational goals (Recognize) and to assure the continuity of the improvement achieved with projects (Replicate/Review), transforming the process from DMAIC to R-DMAIC-R. Nevertheless, this attempt to integrate the organization as a whole was unproductive. The problem still remains: how to integrate the strategies from the organization without having a negativeimpact on other processes and be able to sustain the results of the improvement process for a long period of time?

Perhaps the major barrier for the use of SS methodology is that even when the phases and tools are well-defined and known, there are critical issues on how to perform each one. Here is when systems approach can improve the performance of SS methodology and include elements andtechniques that would help to integrate strategic planning as well as following-up elements into SS. Six Sigma Deliverables The certification process for Six Sigma depends on three venues: training, exams and project. The requirements in each venue are according to the achievement level (green, black and master black belts). In this paper, the basis for defining the set of deliverables required tofulfill the certification needs is the black belt level considering manufacturing processes. Every certification company defined their own and specific deliverables. In most cases these deliverables coincide, and then a minimum standard (Brue and Howes 2006) is already defined by this coincidence (Belair and O'Neill 2007). The following list of deliverables is arranged by phase and the suggested orderto execute the project. These deliverables are the “ideal” in any black belt project but those marked in italics show the standard by coincidence while the rest are those that help to create a solid foundation in the problem solving process. The deliverables recommended for the Recognition phase are:  Mission and vision statement  Strategies definition  Construction of “a problematique” ...