A Graphical Method to Assist Quality Decisions throughout the Product Development Process

ABSTRACT

In product development processes and in the engineering world in general, many situations arise in which a decision must be taken to choose the best alternative or concept from among several already existing ones. Among the most used methods in situations like these are those that use two-dimensional decision matrices, where the concepts or alternatives are compared by evaluating them according to the degree of compliance for preestablished quality criteria.

The finally adopted decision is not only conditioned by the decision maker's assessment of each alternative but also by the weightings initially assigned to the criteria. This means that variation in the assessment of any alternative or in the weighting of a criterion can lead to a distinct alternative being selected. In this article, we propose a graphical method that makes it simpler to view the margin for variation, for both the assessments of the alternatives and the weightings for the quality criteria, that does not affect the finally adopted decision. In this way, the decision-making team can analyze in greater depth the more critical assessments and weightings that, although consisting of small changes, could affect the decision. Finally, the applicability of the proposed method is demonstrated in a case study involving an electrical switch design.

KEYWORDS:

• decision making
• decision matrices
• concept selection
• graphical method
• quality criteria

Additional information

Notes on contributors

José Benito Bouza-Rodríguez

José Benito Bouza-Rodríguez has a master's degree in industrial engineering from the University of Vigo, Spain, and a Ph.D. in industrial engineering from the same university. He is currently a senior lecturer in the Department of Engineering Design at the University of Vigo. He has conducted different works related to design methodologies, decision making, reverse engineering, geometric modeling, biomechanics, and engineering graphics. Many of these works have resulted in publications in journals, conference papers, books, and monographs. He is currently collaborating with different companies and he is listed as principal researcher on many research projects and R&D contracts. He holds several patents and utility models related to industrial engineering.

Alberto Comesaña-Campos

Alberto Comesaa-Campos has a master's degree in industrial engineering from the University of Vigo, Spain. He carried out the doctoral studies at the University of Vigo. During the period 2008–2010 he worked as a visiting professor at the University of Vigo. From 2010 to the present he has worked as an assistant professor at the University Centre of Defence in Marı´n, Spain. He has conducted different works related to engineering design, decision making, engineering projects, and engineering graphics. Some of these works have resulted in publications in journals and conference papers. He holds several patents related to industrial products.

Agustín Menéndez-Díaz

Agustín Menéndez-Díaz has a master's degree in mining engineering from the University of Oviedo, Spain, and a Ph.D. in mining engineering from the same university. He is currently a senior lecturer in the Department of Engineering Design at the University of Oviedo. He has conducted different works related to mathematical methods in engineering, subsurface modeling, geological sciences, and engineering graphics. Many of these works have resulted in publications in journals, conference papers, books, and monographs. He is currently collaborating with different companies and he is listed as principal researcher on many research projects and R&D contracts.