Control of parts : parts making in the building industry

Abstract

The thesis advances a diagramming tool called PAct. Each diagram is a model of a "value adding" enterprise, representing materials processing, parts manipulation and assembly, and the agents involved. Its purpose is to support analysis of the interactions of agents and parts in production flows which are too complex to be held intuitively in mind. In exercising the tool in simple demonstrations of both conventional and "innovative" instances of parts production, two basic diagram patterns appear: "dispersed" patterns in which agents control (make) parts independently, and "nested" or "overlapping" patterns where some agents control and others indirectly control (design). Descriptive power of complex making processes is increased by putting both "processes" (changes made by agents) and "products" (parts) together in the same diagrams. Designing is found to be vital but not the only or even the dominant relation between agents in value added flows. PAct grew out of questions regarding difficulties the design professions often have, when trying to improve conventional house building practices. However, the tool is more generally useful to product manufacturers, building industry researchers, historians of technology, and designers who need accurate descriptions of value added flows of any parts making enterprise, to supplement present analysis tools.