The Assignment: For this assignment, we will be doing something a little fun for a change. We will be creating a couple of "impossible figures" using the ISOMETRIC grid in AutoCAD.

STARTING PRACTICE: A few days ago, we completed a PENROSE TRIANGLE in AutoCAD, using the ISOMETRIC GRID. The figure to the right expands upon the original triangle design. START WITH the figure of cubes to the right. Using the ISOMETRIC GRID and any other AutoCAD techniques that you wish, recreate the figure. Make sure that the cubes are all the same size (say 1.0) and that the distance between each cube is the same (say 0.5). As we know all about how to color a figure using the HATCH command, please shade your figure as it is in the original. SAVE this file to your AUTOCAD 13 folder, call it DRAWING 1.dwg.

SELECTING YOUR OWN FIGURES: Once you have finished the practice Penrose Triangle Cubes figure above, follow this link to a webpage of optical illusions, most drawn using only simple lines.

When selecting your figures, click on the "GRAYSCALE" links and pick the figures that you would like to recreate.

If you have not yet done so, complete the OPTICAL ILLUSIONS BELLRINGER that outlines your selection of your two figures for this assignment, but to reiterate- You will selecting TWO optical illusions to recreate, a SIMPLE figure and a CHALLENGE figure The SIMPLE figure will give you a chance to choose a figure to get your feet wet. Select an illusion that you understand clearly and that will be relatively simple to create in AutoCAD, just to get your confidence up.

On your second selection, please select a CHALLENGE figure that you know will push your limits (and possibly your patience) a little bit. Select a figure that is hard to understand or complicated in its construction.

Especially on your SIMPLE figure, try to pick a figure that has lines primarily on the ISOMETRIC grid and you should be fine. Your figure will not necessarily be easy to recreate in AutoCAD, but you have the skills! DO YOUR BEST to recreate them, using any AutoCAD tools you wish, such as grid, offset, etc. Most of these figures involve TRIMMING lines in ways that figures could not actually be cut in real life.

MAKE SURE TO USE THE HATCH COMMAND TO INCLUDE ALL SHADING FOR YOUR DRAWINGS, SUCH AS THE GREY SHADES IN THE FIGURE ABOVE!

SIGNING YOUR WORK AND SAVING: When you are done with your figures, use the AutoCAD TEXT Tool to put your name and the year on your drawing. From AutoCAD, SAVE your file to your AUTOCAD 13 folder as:

lastname_impossible_cubes.dwg

and

lastname_impossible_figure_SIMPLE.dwg

and

lastname_impossible_figure_CHALLENGE.dwg

These have traditionally been posted In the hallway on the bulletin board, so give me good stuff!