Overview

If in doubt, make it stout,

Use only materials you know about.

Anonymous

Engineers commonly use materials whose properties they do not properly understand, to form them into shapes whose geometries they cannot properly analyse, to resist forces they cannot properly assess, in such a way that the public at large has no reason to suspect the full extent of their ignorance. John Ure, 1998

Engineers commonly use conventional materials (metal, timber, concrete) for construction. In general, these materials require considerable manufacturing effort to change them from the "raw" state to the useful shape and size specified in a design. Consequently, it is always prudent to plan and generate carefully prepared drawings of parts and assemblies. This approach is based on old engineering caution. "It is always easier to rub it out on paper than in steel."

This carefully planned and persuasively prudent approach requires relatively long timeframes to proceed from idea through working prototype to final product. The colloquial term used for the lead-time required to progress through the various phases of design to final product is "cradle to launch" (CTL) time. Agile manufacturing is the title used to describe manufacturers with the capacity to respond quickly to changes in consumer demand, with shorter CTL times. The automobile industry, where model and style changes vary with fashion, with CTL times of five to seven years in the past, agile manufacturing now aims for CTL times of three years or less. The Ford Pinto disaster is in...