Analysis of Impact of Requirement Change on Product Development Progress Based on System Dynamics

Requirement changes occur frequently during the product development process owing to diverse and personalized customer needs. This necessitates multiple reworks of the development task, causing delays. Therefore, it is necessary to analyze the impact of requirement change on the progress of product development. First, the development task is divided into three phases: concept development, detail design, and pilot production. Reworks that are a result of development error or changes in information are analyzed along with the reworks caused by requirement changes, which are the focus of analysis. Then, development task activities and relationships are quantitatively described, and a simulation model is built based on the system dynamics method. This is combined with a practice case of product development, and the impact of requirement change on the progress of the development task is analyzed. The analysis shows that requirement changes greatly increase the development task duration and uncertainty of the development task schedule. The development task schedule is most sensitive to the deadline for requirement change, and the impact of a requirement change occurring at the later phase is greater.