Fundamental Study on Optimal Design Method of Product Lineup by Monotonicity Analysis of Mini-Max Problem

The simultaneous and integrated design of a series of products has become extremely important under the diversification of customer demands due to the maturity of society. The complicatcdness and associated difficulties of their design activities are caused not only by the diversity of products but also by the entire shape of the supply chain. When viewing such a situation through a chain of parts, intermediate products, and final products, the lineup design problem of intermediate products must be another focus toward enhancing the integrative product performance. The lineup design problem is characterized by the simultaneous design of the ranges where respective products cover and the contents of those products. This paper proposes a two-phase method for the lineup design problems. The method consists of designing a framework and optimizing contents under the framework. The latter phase is formulated as a nested mini-max optimization problem. An effective and efficient optimization scheme is constructed by employing monotonicity analysis. Finally, an application to universal motors is demonstrated for ascertaining the validity and promises of the proposed design method. © 2022 Japan Society for Precision Engineering. All rights reserved.