GUIDING CONCEPTUAL DESIGN THROUGH BEHAVIORAL REASONING

This paper presents a model for conceptual design based on an explicit behavioral reasoning step to guide the design process. Rather than ma pping directly from function to form, we treat conceptual design as a two-step process, first transforming functional requirements to a beha vioral description and then matching physical artifacts to this behavi or. We believe that behavior, in terms of physical principles and phen omena, provides a natural bridge between functional requirements and p hysical artifacts. Behavioral reasoning breaks preconceived links betw een functions and artifacts, allowing for innovative solutions to be f ound. A new representation called behavior graphs (derived from bond g raphs) has been developed to facilitate behavioral reasoning. This pap er discusses behavior graphs and their use in a design synthesis model that generates systems of pre-defined embodiments (e.g., motor, sprin g, valve) to meet functional requirements given in terms of input and output parameters (e.g., force, pressure, displacement, voltage). An e xperimental computer program implementing this model is discussed and illustrative examples presented.