Optimal Design and Robustness Assessment of Product Family Considering Quantity Discounts in Supply Chain
Product family design generally aims at overhead reduction due to component commonality meeting various customer needs. Quantity discount is one of the most crucial factors to consider cost reduction effects. However, it also contains the risk of drastic profit decrease when a demand or supply capacity unexpectedly changes. This research aims at proposing an optimal design method of product family with assessment of robustness of expected profit. First, this paper discusses the structure of the optimal design problem of product family considering quantity discount in supply chain. The modeling of quantity discount faces a problem of discontinuous of design spaces. The discontinuity of a design space makes optimization more difficult. This research proposes a method to solve it with reasonable calculation cost by utilizing branch and bound and linear programming. A case study of designing a product family of drip coffee maker demonstrates the application of the proposed method in order to verify it.