Class discussion
Physical Puzzles
We didn't have time to discuss the ins and outs of physical
puzzles, but I include these notes for your reading
pleasure:
From the Puzzle Museum (http://puzzlemuseum.com) comes a
discussion and taxonomy of physical (or mechanical) puzzles:
"A puzzle is a problem having one or more specific objectives,
contrived for the principle purpose of exercising ones ingenuity
and/or patience. A mechanical puzzle is a physical
object comprising one or more parts which falls within the above
definition... A puzzle should be classified by
the problem that its designer intended the solver to encounter whilst
attempting to solve it... A puzzle will be referred
to as 2D if its third dimension is irrelevant (e.g. thickness of
paper or plywood or an operation involving a third dimension such as
folding). Most standard jigsaws are 2D; however jigsaws with sloping
cuts in fact have a relevant third dimension, so they must be classed
as 3D. The 14 main classes are as follows:
DEXTERITY puzzles require the use of manual dexterity or other
physical skills in their solution.
ROUTEFINDING puzzles require the solver to find either any
path, or a specific path as defined by certain rules.
TANGLEMENT puzzles have parts that must be linked or unlinked. The
linked parts, which may be flexible, have significant freedom of movement in
relation to each other, unlike the parts of an interlocking puzzle.
OPENING puzzles are puzzles in which the principle object is
to open it, close it, undo it, remove something from it, or otherwise
get it to work. They usually comprise a single object or associated
parts such as a box with its lid, a padlock and its hasp, or a nut
& bolt. The mechanism of the puzzle is not usually apparent, nor
do they involve general assembly or disassembly of parts that
interlock in 3D.
INTERLOCKING puzzles interlock in three dimensions, i.e. one
or more pieces hold the rest together, or the pieces are mutually
self-sustaining. Many clip-together puzzles are
"non-interlocking".
JIGSAW puzzles are made as if cut or stamped into pieces
from a single complete object, and the principle objective is to
restore them to their unique original form.
ASSEMBLY puzzles require the arrangement of
separate pieces to make specific shapes without regard to the sequence of that
placing, they may clip together but do not interlock in 3D. Some have a
container and are posed as packing problems.
PATTERN puzzles require the placing or arrangement of
separate pieces of a similar nature to complete surface patterns
according to defined rules. The pattern required may be the matching
of edges of squares, faces of cubes, etc. The pattern may be color,
texture, shape, etc. Where the pattern is due to differences in shape
they must be sufficiently minor not to obscure the similarity of the
pieces.
FOLDING & HINGED puzzles have parts that are joined
together and usually do not come apart. They are solved by hinging,
flexing, or folding.
SEQUENTIAL MOVEMENT puzzles are those that can be solved
only by moves which can be seen to be dependant on previously made
moves.
JUGS & VESSELS have a mechanical puzzle or trick in
their construction that affects the filling, pouring or drinking there
from.
OTHER TYPES OF MECHANICAL puzzles and objects are puzzle objects
that do not easily fall into the above categories and cannot be
categorized into sufficiently large groups to warrant their own major
class. Included in this group are Balancing, Measuring, Cutting,
Math, Logic, Trick, Mystery, & Theoretical puzzles. Also provision
is made for puzzles pending classification.
AMBIGUOUS PICTURES & PUZZLING OBJECTS in which
something appears impossible or ambiguous.
NON-PUZZLE but related EPHEMERA has been included as most
puzzle collections include related ephemera which, whilst not strictly
puzzles, need to be classified as part of the collection."
Burr Puzzles
"A Burr puzzle consists of at least three rods intersecting
each other at right angles. The most famous and well known type is the
six piece burr where three sets of two rods intersect each
other." From the IBM Burr Puzzle
site.
A Burr puzzle is made from six intersecting
pieces. Typically, each piece is 2×2×6 units in dimension, although
there are many variations, including planar Burr puzzles, where the
pices are 1×4×6 (See Vreugd's
Burr). I've been experimenting with 2×3×4 puzzles (See Walter's Burr). The parts of
the piece that protrude from the center are the same for every
piece. The interesting thing is what happens in the interior regions
of the puzzle.
There are three classes of 2×2×6 Burr puzzles: (1)
puzzles with a solid (key) piece; (2) puzzles that slide
apart--typically into hemispheres; and (3) puzzles that unlock with
one or more slides.
I've modeled in Lego four puzzles featured on the IBM site:
You can make your own puzzles using Lego. (In building with
Lego, the key is: two bricks wide = five plates high.) You can
make a unit cube by using a standard 2×2 brick and adding a plate and
flat plate. Thus, to make a Burr-puzzle piece, you should start with a
2×12 brick and expand from there. I find that using the 1×12 bricks
with holes to add stability to my Burrs.
Download LEGO
rendering tools at
http://ldraw.org
You can design individual burr pieces at
http://epigram.media.mit.edu/walter/burrdesigner.html.