Design Achievement Model for Planning Creative and Concurrent Design Process

Planning of an upstream design process that includes creative and concurrent activities has become more important for product development in a competitive market. A significant characteristic of upstream planning is that the design process is one of knowledge creation. During this process, a designer makes progress toward a more advanced knowledge level that corresponds to a more advanced design achievement. In most cases of a creative and concurrent design process, however, a designer has to compromise design achievement because of constraints such as delivery time, cost, and another designer’s intention. Therefore, in planning a design process, it is more essential to set an acceptable level of design achievement and to predict whether or not a planned design process can ensure this level, than to predict the design time needed to totally achieve the design goals. This paper proposes a new method of design process planning that focuses on quantitative prediction of knowledge level achieved in a creative and concurrent design process. A growth curve model using fuzzy numbers is introduced to predict the final achievement of each task and final achievement of consistency between tasks after running a planned design process. The reliability model of a serial system is used to calculate the total acceptability of the design achievement. An experimental system that supports design process planning based on the proposed method is developed. This paper demonstrates its application to a student design project in order to show the power of the method.Copyright © 2008 by ASME