Abstract
Long-lifecycle system such as ship and plant undergoes many changes throughout their entire lifecycle. These changes force systems to become inefficient or even inoperative. Likewise, future changes lead to challenges that have to be met within the design of system. Consequently, long-lifecycle system strongly requires the ability to be changed easily/rapidly in response to change request and being adaptable to changing environments. This research aims to support for product design in early stage that enables to minimize the lifecycle cost. Changeability of system provides the convenience of counteract future changes and long-term operation. To evaluate changeability, we tried to trace change propagation and specify the area effected by change request. However, in some cases, increasing changeability leads to inefficiency. Thus, design for changeability requires considering future changes that are planed or expected. This research adopted the form of scenarios for describing future changes. As mentioned above, this study tried to develop the method of product design that enables to respond to future change in early stage. And we implemented it as a prototype system and evaluated the proposed method by a case study.