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Vol. 1, No. 2......... |
Newsletter of the
Polymorf.networks |
March ,
2004 |
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New lessons featured at
Knowhere |
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> |
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Two new online lessons on structural
and mechanical engineering have been added to |
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the Knowhere section of the Polymorf
web site. The lessons demonstrate how the |
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structure, or geometry, of space
influences the engineering of man-made structures. This |
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is a continuation of the theme already
presented in the two prior lessons on the symmetry |
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of polyhedra and the
structure of
crystals. |
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The structural engineering lesson,
entitled Building stability, covers |
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basic structures such as columns and beams, bridges,
buildings, |
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spaceframes, and towers. Dozens of models built with Polymorf |
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are used to
demonstrate fundamental engineering concepts such |
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as stability,
forces and reactions, load bearing, bending moment, |
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moment of inertia, stresses,
lattice action, plate action, etc. The |
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section on bridges, for example, shows
how simple models of classic truss bridges can |
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be built and load tested to failure to
determine their ultimate strength and mode of failure. |
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The results of the tests are graphed
in order to compare the performance of the different |
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designs relative to the maximum load
they carried versus their span, height/span ratio, |
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and their weight. In the section
on spaceframes, Polymorf models of triangular, square, |
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and rectangular
lattices show how they are all derived from one common structure, the |
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octet truss.
Since this structure is identical to the FCC crystal lattice presented in
the |
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prior lesson on the
structure of crystals, the connection between natural and man-made |
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systems is
convincingly made. This lesson is indexed at
www.pollymorf.net/knowhere. |
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In
Gizmoneering, Polymorf models of simple
mechanisms, or gizmos, |
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show how
machines convert and transmit energy to do work. Basic |
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structural
elements such as hinges, bearings, pivots, hubs, wheels, |
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swivels,
pistons, etc. are combined to create a revolving telescope, |
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hand held
pincers, robots, and fanciful critters. Complex mechanisms |
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Gizmo |
comprised
of more than one gizmo illustrate how mechanical systems |
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are
integrated seamlessly to perform complex tasks. Basic concepts |
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presented in the
previous lesson on structural engineering such as force displacement |
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and dissipation, and
static equilibrium are related to how machines combine mobile and
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immobile features to
perform a given function. Indexed at
www.polymorf.net/knowhere. |
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Many of the structures
shown in these two engineering lessons can be built with the new |
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2000 piece
Engineering set that has been added to the
catalog. |
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Polywood
Another new feature of the site is a
collection of cartoons, |
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short
animations, and stereo images called Polywood.
See spiders |
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catching flies,
cats chasing mice, a dog riding a horse, and even an |
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eagle feeding
its young. Lessons are also presented on how to make |
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stop-action animations and stereo images of your favorite |
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Polymorf models.
Its lights, camera, action! at
http://www.polymorf.net/polywood.htm |
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Last but not least,
the free clip art gallery has been greatly
expanded with dozens of new |
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animations that you
can copy and download for your own personal use. |
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See
previous issues of the 3Doodlings newsletter |
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Home |
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