A Functional Theory of Design Patterns

Design patterns specify generic relations among abstract design elements. In the domain of physical devices, design patterns, called generic teleological mechanisms (or GTMs), specify generic functional relations and abstract causal structure of a class of devices. We describe a functional theory of acquisition, access, and use of GTMs, but focus on their use in analogical design. In this theory, GTMs are acquired by abstraction over known designs, accessed by goals of adapting a familiar design to meet new design requirements, and used by instantiation in the context of a familiar design. This account of design patterns is one part of a general theory of analogical design called model-based analogy (or MBA). The IDEAL system implements the MBA theory for conceptual design of physical devices and evaluates its account of design patterns.