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Old 06-11-2017, 09:28 AM
LSLGuy LSLGuy is offline
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Join Date: Sep 2003
Location: Southeast Florida USA
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Originally Posted by Francis Vaughan View Post
Part of the question is to define "engineered". Engineering, if you take the idea across all the various domains that engineers work in, and try to distil the "engineeringness" out of them really come down to the application of domain skills, process, and knowledge, to make something that meets its specification.
This is a superb distillation.

Which moves the onus onto the specification. Simple specs (e.g. a homemade dog house about this [waves arms] big.) are trivial to meet and require only the most rudimentary of engineering. It does require some engineering; you can still build a doghouse that doesn't work at all or that collapses or falls apart. We've all seen this cartoon of several ways to fail to successfully engineer a simple tree swing.

The more extreme the specs the more engineering required to meet any of them, much less all of them.

Extremity can be size (a gigantic bridge or an almost quantum-scale transistor), environment (deep in the ocean, inside a living body, out in space, high or low temperatures), physical strength, bleeding edgeness of tech, reliability, production efficiency, cost. Et cetera for many more parameters.

The hardest tradeoffs are the antithetical X/Y ratios. e.g. It needs to be strong and light: strength/weight needs to be a large number. It needs to be reliable and cheap: lifespan/cost must be large (or cost/day of life must be small).

These antithetical ratios, of which there are many, lead to the classic trilemma saying: "Cheaper, faster, better. Pick two."

A real project doesn't have a mere trilemma; it has an icosalemma at each of thousands of interlocking junctures. A kilo-icosalemma. And each decision feeds into the connections to all the others. So soon you arrive at the kilo2-icosalemma AKA the dreaded megicosalemma.

Last edited by LSLGuy; 06-11-2017 at 09:30 AM.