複雑システムの開発における製品アーキテクチャ選択

VW、日産、マツダの事例

抄録

This study discusses the logic behind the selection of product architecture in designing complex products. This study examines the nature of product architecture by looking at the way how a product system is partitioned, the size of modules, and the interface rules defining fixed and variable elements of the product systems. I analyze new product development approaches proposed by Volkswagen (MQB: Modular Transverse Matrix), Nissan (CMF: Common Module Family), and Mazda (CA: Common Architecture). The common logic of these approaches is that they attempt to reduce expost coordination efforts to develop individual vehicles by increasing ex-ante coordination in an advanced development phase. In MQB and CMF a vehicles system is partitioned into smaller subsystems (the size of modules of MQB is smaller than that of CMF), and a variety of vehicle models is created by changing the combination of pre-developed modules. In Mazda’s CA it creates different vehicles by copying the common engineering principles and standard design structures in similar shape or ratio. VW’s MQB defines the modules and the interfaces as fixed elements for designing individual vehicles, while Nissan’s CMF includes both fixed and variable elements within each module, and Mazda treats the engineering principles as fixed rules. The case study illustrates that the selection of product architecture is likely to reflect the differences in complexity of product portfolio and the size of sales volume among the firms. Those firms, such as VW and Nissan, with a large product variation and sales volume may prefer to reduce workloads for developing individual models even though the modularization of the vehicle system would require huge engineering man-hours in advanced development phase. On the other hand, Mazda seems to avoid such an approach because it imposes too much fixed costs. Overall, the nature of product architecture will depend in part on the nature of the firm’s product market strategy.