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Spinning plates on poles used be a popular event, but is
now seen as totally passé. (see link) Perpetually
Plates Apparatus is a device which replicates this
famous cabaret action performance.
It consists of the poles, spinning plates, and a
arm that reaches
out periodically to grip then agitate
poles, always just in the nick of time, preventing the
wobbly plate(s) from falling to the ground. A constant
of falling rice particles adds to the spectacle, as they
bounce randomly off the rotating plates, and get flung
against the protective glass front.
Sensors combined with motion detection and processor
analysis ensure that the whole operation is
but fully automated. Place it in a shop window and leave
without explanation to spin away.
Who will build it for me? Ha
[xenzag, Dec 01 2018]
||Er, does this involve bits of buttered bread and cats?
||Eh no, but there could be a human heads on the
plates variation - care to offer yours? :-)
||Seeing as it's completely empty, it would unbalance
||I don't understand what you are asking me? Could
you rephrased your question?
||You could bounce lasrs off the plates to make a pretty
pattern on the ceiling.
||Also, I have some vague memory that IBM made the first
barcode scanners with a spinning mirror that directed the
laser. Wikipedia says, "Most of them [a particular kind of
barcode scanner] use a single rotating polygonal mirror and
an arrangement of several fixed mirrors to generate their
complex scan patterns
||Most (probably all?) laser-based barcode scanners, regardless of
manufacturer, do that. Look into the windows of a self-checkout machine
next time you use one. There's a spinning polygonal mirror in there
(probably hidden, though) and the beam bounces off of that and then off
of some more mirrors to generate the pattern of crossed lines. The
important thing is that it's still only a single beam, meaning only one point
is illuminated at a time, and the length of one of the lines is traced before
the beam makes the next line. This converts the spatial reflectance
pattern of the barcode, in just about any orientation, to a temporal
reflectance pattern, which can be interpreted by the computer.
||There are now many handheld barcode scanners that use a 2D camera
instead of a scanned laser beam. Also, librarians in my city used to (around
15 years ago) use "pen" barcode scanners that just had an unfocused red
light (maybe laser, maybe LED) and they had to swipe the pen along the
barcode at a constant rate to scan it.
||Laser printers also use polygonal mirror-based laser scanners, though they
only scan in one axis and don't use secondary mirrors to break up the