Evolution of property predictability during conceptual design

A product is designed with the purpose of possessing certain properties, which are prescribed as requirements in the design specification. This paper studies the evolution of property predictability during the early phases of design in a case study context. By the term property predictability, we refer to the designers’ confidence in predicting product properties based on the available information. In the case study, with use of the produced design models at four different stages of concept concretisation, the designers evaluated their confidence in predicting product properties related to the requirements set for the task. As a result, we identified three different patterns of property predictability behaviour. These patterns consist of properties of which predictability is relatively high throughout the early phases of the design process, properties of which predictability shows a high increase during the progression of the early phases of the design process, and properties of which predictability remains relatively low throughout the early phases of the design process. We believe that an awareness and understanding of such different behaviours of property predictability is important for both designers and design project leaders when determining a proper timing and criteria for selecting the design concept for further development.