George Hart

As seen in class, the Great Stella program has a large library of polyhedra and can do various kinds of manipulations on them. For this exercise, we start with simple polyhedra and join them face-to-face to make larger forms. The faces can be unfolded into a net and printed out to be assembled from paper (or plates of steel or whatever).

See the Help file for basic manipulations. For this exercise, you need to understand platonic polyhedra, selecting faces, storing polyhedra in memories, the Augment operation, mirror image reflection, and nonuniform scaling. Be sure you understand how the Augment operation matches the selected faces and that you can rotate with the arrow keys before accepting it. We discovered that the program sometimes crashes if you do these exercises with more than one sub-window open, so type Ctrl-1, which will close all but one sub-window. That is the digit 1. Later you can do Ctrl-2 or Ctrl-3 to reopen 2 or 3 sub-windows.

6) Star
made of Dodecahedra. This is easy if you use the fact
that Great Sella understands the symmetry and can augment to all
equivalent faces. Start with a dodecahedron. Surround all faces with a
chain of four more dodecahedra. At the tip of each chain, branch out
five ways with with another chain of four. Put a dodecahedron where
these meet in pairs. Then add two more chains to each tip, which meet
in groups of threes.Then a final dodecahedron goes at each tip. Note
that the struts (chains) can be any even length.

7) Something Original. Using similar techniques, but perhaps different building blocks, create something original of your own design that is interesting, but not too complex. Next week you will print out its net, cut it out from paper, fold, tape, and assemble it.

Show the TA images of your constructions. You can be checked off at the start or end of class, or email images (taken from a different viewpoint) as attachments. Do not email the Great Stela files, as they can be large.) Have your Great Stella file that answers #7 saved somewhere where you can access it in class to show everyone.

Questions 1-6 are due tuesday Feb 17th. Question 7 is due in class thursday Feb 19.

7) Something Original. Using similar techniques, but perhaps different building blocks, create something original of your own design that is interesting, but not too complex. Next week you will print out its net, cut it out from paper, fold, tape, and assemble it.

Show the TA images of your constructions. You can be checked off at the start or end of class, or email images (taken from a different viewpoint) as attachments. Do not email the Great Stela files, as they can be large.) Have your Great Stella file that answers #7 saved somewhere where you can access it in class to show everyone.

Questions 1-6 are due tuesday Feb 17th. Question 7 is due in class thursday Feb 19.