Multimodal Analogies in Modelling and Design

Drawings, on the one hand, and teleological models, on the other, are two ways of understanding and communicating design information. Drawing on previous work, Structure-Behavior-Function (SBF) theory claims that teleological knowledge is comprised of three basic kinds of knowledge: structural knowledge, behavioral knowledge, and functional knowledge. However, the design task, in practice, revolves around drawings. For example, Computer-Aided Design (CAD) software manipulates and produces drawings, and to produce a design is to produce a set of documents that primarily consists of drawings of that design. And yet, drawings can, at best, represent only structural knowledge, and even that incompletely, as components’ roles in the design are not and cannot be determined solely by the drawing. Two questions motivate this research: (1) what role, precisely, do drawings place in the design process? and (2) how can we enhance CAD tools to make more direct use of teleological knowledge? This work explores two problems: model construction and design generation. The problem of constructing an SBF model of a mechanical device from a drawing can be solved in a robust and tractable way using analogical reasoning, by reasoning from visual and topological differences to structural, causal, and functional differences in models. Patterns of adaptation and transfer can be captured by Generic Visual Teleological Mechanisms (GVTMs), generic patterns of adaptation that capture particular abstractions. Likewise, the problem of design generation, proceeding from a functional specification to a drawing associated with a complete SBF model, can be solved in a robust and tractable manner using analogical reasoning from functional differences to structural and behavioral differences in models, and ultimately to visual differences in drawings. Patterns of adaptation, here, can be effectively solved by Generic Teleological Drawing Mechanisms (GTDMs), capturing similar patterns to GVTMs, but proceeding from function to drawing instead of the reverse. Both are essentially constructive, and together help to elucidate the nature and interplay between visual structure and topology, on the one hand, and causality and teleology, on the other hand, in modelling and design.