This paper presents a modified Taguchi methodology to improve the robustness of modular product families against changes in customer requirements. The general research questions posed in this paper are: (1) How to effectively design a product family (PF) that is robust enough to accommodate future customer requirements? (2) How far into the future should the designers look to design a robust product family? An example of a simplified vacuum product family is used to illustrate our methodology. In the example, the customer requirements are selected as signal factors; the future changes of customer requirements are selected as noise factors; an index called the quality characteristic (QC) is set to evaluate the product vacuum family; and the module instance matrix (M) is selected as the control factor. Initially a relation between the objective function (QC) and the control factor (M) is established, and then the search space is systemically explored using the simplex method to determine the optimum M and the corresponding QC values. Next, various noise levels at different time points are introduced into the system. For each noise level, the optimal values of M and QC are computed and plotted on a QC-chart. The tunable time period of the control factor (in the example, the module matrix, M) is computed using the QC-chart. The tunable time period represents the maximum time for which a given module matrix can be used to satisfy the current and future customer needs. Finally, a robustness index is used to break up the tunable time period into suitable time periods that the designers should focus on while designing product families.

This content is only available via PDF.
You do not currently have access to this content.