CS 285: SOLID MODELING, Spring 2000

Assignment #5 : Snap-together N-gon Tiles

We want to create part descriptions of modular tiles in the shape of flat, regular, n-sided polygons that could be used to assemble Platonic solids or Archimedean solids. For that purpose we need equilateral triangles, squares, regular pentagons, hexagons, octagons and decagons (10-sided). We will make only one type of tile for each type of N-gon. In particular, 4 identical triangle-tiles should snap together into a tetrahedron, 6 identical square tiles should assemble into a cube.

The focus is on the design of the edges, that should allow any two such tiles to hold together at a wide range of dihedral angles -- and also come apart without breaking the tile. Of course this means that all parts must have the same edge length -- let's standardize on a lenght of 2 inches.

Phase One -- Conceptual Tile Design
DUE: Wednesday March 15, 2000

Form two-person "toy companies" with the following pairing: Think about different approaches that will lead to a promising tile. Make sketches (by hand or by computer) of the proposed form and turn them into overhead foils or on-line displays. Annotate these drawing with some remarks about how such tiles are supposed to snap together and come apart again; perhaps add a foild or two with some bullets that summarize your approach and reasoning.
Bring this design proposal to class on Monday, where you (as a pair) will make a "formal" 5-minute presentation to a bunch of "investors" (the rest of the class) and try to convince them that your company's tile is the best.

We will then discuss the feasibility of the various design ideas and define the scope for the execution of a final, detailed design suitable for prototyping on the FDM machine. The general context of your design is the goal to make a (cheap) injection-molded part that could be made by the millions.

Phase Two -- Implementation
DUE: Wednesday March 22, 2000

Finalize your designs for FDM prototyping.
Use booleans. Start from the basic flat prismatic tile, and add "knobs", extrusions, by adding (union) the nessary geometric shapes; cut slots, holes, or make indentations by subtracting simple primitive shapes.

Run the SLIDE files through Jianlin's tools to make SSL files for the FDM machine.
{Jianlin -- what machines should this code be run on ? -- Please post instructions}
{OK to use any CAD tool, e.g. Solidworks, and go directly to clean STL B-rep, if that makes life easier.}

Build two triangle tiles, and check that they work.
{If nobody in your team has any contact with someone who knows how to run the machine, let me know, and I will do it with you or find you a contact.}

If necessary refine your design.
By wednesday, bring at least two tiles to class that work.

Later, with my OK, you may build a larger batch; probably eight triangles and three squares, so that you can make 3-4 interesting closed solids.

Do this work in the above assigned 2-person teams.

See also: Delta Blocks

PREVIOUS < - - - - > CS 285 HOME < - - - - > CURRENT LECTURE < - - - - > NEXT
Page Editor: Carlo H. Séquin