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 mapping directly from function to form, we treat conceptual design as a two-step process, first transforming functional requirements to a behavioral description and then matching physical artifacts to this behavior. We believe that behavior, in terms of physical principles and phenomena, provides a natural bridge between functional requirements and physical artifacts. Behavioral reasoning breaks preconceived links between functions and artifacts, allowing for innovative solutions to be Jbund. A new representation called behavior graphs (derived from bond graphs) has been developed to facilitate behavioral reasoning. This paper discusses behavior graphs and their use in a design synthesis model that generates systems of pre-defined embodiments (e.g., motor, spring, valve) to meet functional requirements given in terms of input and output parameters (e.g., .force, pressure, displacement, voltage). An experimental computer program implementing this model is discussed and illustrative examples presented.