The alternate use of abstraction and refinement in conceptual mechanical design

Abstract: "In this paper we identify the characteristics of conceptual mechanical design problems which make them hard to solve and hard to study. We discuss the relationships between these problems and other cognitive tasks and explain why conceptual mechanical design problems are difficult to study and simulate using the Information Processing paradigm, the theoretical framework for Verbal Protocol Analysis and Expert Systems. The nature of conceptual design goals, constraints, and constraint discovery increase the difficulty of conceptual design problem solving per se and analysis of problem solving methodologies.We postulate the use of alternate abstraction and refinement as a key to successful conceptual design problem solving and problem anaylsis and we identify three types of abstractions: Functional Perspectives, Localization, and Worst Case Evaluation. Protocol episodes demonstrate how alternate use of abstraction and refinement can help designers deal with circular constraints, insufficiency of constraints, and bi-directional function to structure constraints."