The main idea in the Potter's Wheel application is this: the user has a simple
object (a segment, a circle, a square, a triangle or a sinuidal curve) which
can be moved and rotated. There is an axis on the screen and the object is
positioned on the left, on the right or across that axis. When the user is
ready, the application rotates the object around the axis and produces a 3D
rotational image - this process is similar to how potters use clay and a wheel
to make pottery. The trick is that the object orientation relative to the axis
is important. Small changes can cause interesting differences. There are over
80 objects which can be constructed using only the 5 objects above (one at a
time). They are provided as problems grouped in 5 sets (one set for each 2D
figure). In the last version of the application a new figure is added - a free
transformable curve -together with 25 new examples. When transformig the curve
the user has 5 base points -- each point can be moved and turned. Turning
points affects tangents of the curve. The curve is a chain of Bezier curves.
Try to reconstruct a given 3D object by using the provided 2D
Study the various figures produces by a segment. What are their
names and properties.
Study the various figures produced by a circle. Do these
figures have geometrical names?
Study the various figures produced by a triangle. Which of them
can be produced by a segment? Find all 3D solid which have geometrical names.
Study the various figures produced by a square. Which of them
can be produced by a segment? By a triangle? By two triangles?
Study the various figures produced by a sine curve. Which of
them could be reproduced by a cosine cuve?
Find the role of the axis. Investigate the case when the object
crosses the axis.
Try to find out a 3D solid which can be produced by a shape
entirely to the left of the axis, but cannot be produced by the same shape
entirely to the right of the axis. If not possible, then prove it.
Examine the split mode (especially when using the sine curve)
and explain what a rotational object has such appearance.
Create you own sets and problems and give them to others to
Can you find rotational objects around you, in your home, or
out in the street? Create models of these objects. Create your own library of
Try to describe a rotational object with words, so that another
person can rebuild it.
Play with the free-form curve. Try to model various objects
from your everyday life.
Create puzzles with the free-form curve. Let others solve them.
Potter's Wheel is a DALEST application. To see the others go to the