Innovation Study Group

Tuesday, February 21, 2006

Gases and liquids. Solids resist compression, tension, and shearing. Liquids resist compression and tension. Gases resist compression.

One interesting consequence is that this attraction between liquid molecules explains how as trees aspirate water through their leaves they can pull water through their root system which may be 100' down. The equivalent pressure can be 10 atmospheres.

Surface tension arises since water at the surface is pulled down but there is no corresponding upwards force. The result is attraction to nearby molecules called surface tension.

Wettability describes how water spreads out or beads up depending on the surface. Some surfaces have greater affinity for water (which is why your towel dries you off!).

Insects that can walk on water have weights/surface area less than surface tension, and each leg is far enough from the next that each "dent" in the water surface is separate.

Waves travel laterally but the water does not -- it goes up and down or back and forth, but does not propagate sideways.

Some beetles can use the energy in the water surface to echolocate or to sense the sex of nearby insects.

Gradients -- temperature, concentration, and velocity. This last is intriguing -- no matter how fast fluid moves past a surface, there is zero vecolity at the surface. Where the fluid meets the solid the molecules don't move relative to each other -- speed changes happen as you move away from the surface into the fluid.

We (humans) are equipped with various gradient detectors -- visual, spatial, and temporal. It's an edge that matters. Play sound backwards and it is very disconcerting since many instruments have gradual onset and sudden termination.

Tuesday, February 07, 2006

Hi.

We are looking at matter, so this might "matter" to us ... cheers, drl

http://www.smm.org/strangematter/

Wednesday, January 25, 2006

The group is moving gradually through Vogel -- the last meeting was on allometry and scaling of organisms. Very intriguing stuff -- apparenly the surface area of tree leaves and human lungs each measure in the acres! Meetings are every second Thurs. lunch, contact c.mcnamara@ieee.org for details.

At the previous meeting Carl and Curt had a great time talking about the "principle of bumpiness". Apparently Lotusan paint (self-cleaning when it rains), the underside of new Mercedes (reduces drag), and the stinger of a mosquito (mimicked in a needle which hurts less) all use rough surfaces to produce good effects. Where else might this be applied?

http://www.stocorp.com/allweb.nsf/lotusanpage
http://en.wikipedia.org/wiki/Mosquito
http://www.loe.org/shows/shows.htm?programID=02-P13-00015
http://www.germancarfans.com/news.cfm/newsid/2050607.004

Wednesday, December 07, 2005

"Surfaces of and within organisms are curved, most commonly cylindrical ... flat surfaces are less common. By contrast people make load bearing flat surfaces in profusion -- floors, roofs, walls ... Cylindrical elements -- pipes, cans, bicycle frames -- are certainly not scarce but don't dominate."

"Our technology is rife with right angles -- never mind pyramids, it's the 90 deg. angle to which we seem addicted. It appears in almost every door, window, floor tile, box, book pages, many letters of our alphabet, the pockets of my shirt, and on and on. Yet right angles are surprisingly rare among organisms. Tree trunks are generally at right angles to the ground or horizon, but other examples are not easy to find." (Ed.: look closely where a tree trunk enters the ground!)

"We use a few pliant materials -- plastic hinges, elastic bands, rubber pads and so forth; but relative to the abundance of our stiff stuff, soft and stretchy substances are unusual. "

"Our preferred structural materials are most often made of single components above the molecular level, and the values of their properties are the same (isotropic) whatever the direction of measurement -- we mostly use metals and ceramics. Nature's materials are composites, combinations of two or more components, almost always arranged so that the material's mechanical behavior depends on the direction in which they're loaded. "

"Substantial pieces of metal, either pure or alloyed, never occur in nature, even though metallic atoms are crucial to the biochemistry of all organisms... Ours is an overwhelmingly metallic technology ..."

"Both gases and liquids resist being squeezed and thus can be used as structural materials; air and water are the cheapest and most available of substances. ... nature makes elaborate and extensive use of water as a compression resisting material ... but we use it in only a few devices."

"Life may tolerate a reasonable range of ambient temperatures, but organisms are basically isothermal machines rather than heat engines and do their business without depending on large internal differences in temperature. Heat conduction is not a major issue in organisms ... Human technology makes impressively elaborate use of heat conduction bus less of diffusion."

Life's Devices by Steven Vogel, pp. 12-13

The innovation study group is moving from Triz to biomimicry for a while. We have found the works of Steven Vogel, a combination biologist/physicist. We are using an older, less expensive book which is similar to his current text book, and linking his questions for the newer textbook back to the older book. The group continues to meet every other Thurs. over lunch, however we hope that this blog will allow participation from members who are not able to attend.

We are keen on people summarizing or asking questions about the current material -- for Thurs. 12/15 we are covering Chaps. 1-2. Please post your material as a comment or e-mail me at c.mcnamara@ieee.org and I will enter it as new material.

Life's Devices by Steven Vogel, ISBN 0691024189 The book we are using
Comparative Biomechanics by Steven Vogel, ISBN 0691112975 His current textbook
http://www.addall.com/

Curt