Designing with varying design parameters: The Unified Design Process

Designing on the basis of varying design parameters means that alternative design artifacts may need to be employed for different parameter values. In such situations, the potentially broad range of different parameter values renders impractical the production of distinct design versions. Consequently, there is a need for a design process which is capable of managing diversity within the design act itself. This paper presents the unified design process, which addresses systematically the management of design alternatives, by providing a framework for unifying diverging design decisions, based on the fundamental notion of design polymorphism. The Unified Design Method has been recently proposed and applied in the field of Human-Computer Interaction (HCI) for the purpose of achieving universal access, and in particular for the design of interfaces capable of self-adapting to individual users and usage-contexts. The discussion in this paper will be based on the findings of recent research and development work, while some important issues for future research will be also addressed.