Google| Subject | Re: Back To The Egg ... |
| From | Robert D. Baker |
| Date | 2002-04-16 13:48 (2002-04-16 07:48) |
| Message-ID | <a9h323$v6e$1@nd.eastky.net> |
| Client | |
| Newsgroups | alt.cult-movies.alien |
| Follows | Volt |
"Volt" <nospam_dave@prop-pak.co.uk>wrote in message news:Ejiu8.6982$Xf5.510088@news-binary.blueyonder.co.uk...
Voltan
Well, yes a wing has 'ribs' and 'skins', which sound like they belong in
animal, and if you squint your eyes after sniffing glue they might looklike
skeletal parts, but they share little in common with biology, and have fundementally different purposes. Modern aircraft wings are of stressedskin
construction, whereas mammals and things with ribs aren't. I'm nobiologist
but I can't think of any living thing that is built the same way.Because you're not a biologist, and _you_ can't think of single example of what might be single exception, you've made your point? Logical debate doesn't work that way, Volt. I've studied biology, physics and a little engineering - it's a non-disputed scientific FACT that mankind's solutions to engineering problems mirror nature's solutions to the same problems. People write books on this stuff.
Fleas, ants and crabs have structural exoskeletal skins, but I don't think they have supporting structure equivalent to stringers, ribs and spars to take bending and torsion loads.OK, here's a quote for ya. From "Life's Devices" by Steven Vogel, ISBN: 0-691-02418-9, chapter 12, page 292 (paperback edition)
" Hollow Cylinders
The utility of tubes, mentioned earlier when we talked of flexural stiffness, has been evident to both nature and the engineers. We use them as subsystems in building bicycles and racing cars and as entire systems in so-called monocoque aircraft fuselages, cylindrical storage tanks, glass jars, and metal cans. Nature also uses them in diverse places - bamboo stems, vertebrate long bones, insect, spider and crustacean appendages, the wing veins of insects (just noted), the feather shafts of birds. Sometimes they contain the entire organism - lots of thread-like algae are arranged this way, although it seems unclear how much of their stiffness is due to fluid pressure rather than to being a tubular beam. Microtubules (Figure 13.4), stiffening elements in cells, are also hollow cylindrical beams - arranged as helices of two sorts of protein molecules. My colleague, Wainwright (1988) argues forcefully that the cylinder is the basic shape in the design of organisms. Indeed, there are lots more cylinders than just the hollow ones categorized here - solid struts and internally pressurized containers appear elsewhere in this classification.
So the link with aerospace design and biology in
this case extends no further than aesthetics.I think you don't understand what 'aesthetics' means. It _doesn't_ mean "things that are simply similar in appearance", which seems to be the meaning your attaching to it.
So the point stands that the SJ spaceship's 'ribs' just happen to looklike
ribs, they'd probably be a different material and possible even serve a completely different purpose.No, the point doesn't stand at all. Ribs are structural support mechanisms designed to strengthen (and protect) a cylinder. It doesn't matter if the cylinder is a spaceship or your torso, the purpose is the same.
I can't believe such an advanced race would
resort to hunting creatures and chopping them up for spaceship parts.Uhm.....what the devil are you talking about? Twasn't me that said it, and I thought it was a bit of a joke.
But I agree with you that nature does often get the basic ideas right and that good engineering is sometimes inspired by her creations, it's justshe
struggles with uniformity and her material selection is limited to things that grow.I think you need to broaden your horizons. "nature does often get the basic ideas right" Geezus H. Keerist on a crutch. Mechanics are mechanics, a lever is a lever. You either get it right or you don't get it at all, and you often don't get a second chance - ask any bridge engineer. Nature was building complex mechanical devices _long_ before man did. Who flew first, Davinci or the birds?
2002-04-08-
