Download the template: http://i.imgur.com/D6nOq.jpg
After you download the template you can increase the size of the template if you'd like so that you can make a bigger version. I tape the templates to poster board then cut with a hobby knife. I fold the poster board then use scotch tape to hold them together.
The templates are not 100% perfect. So if you build this model, you might have to squish the columns a little or move the pieces a little to get it to look just right. These are my favorite illusions. From one angle everything looks perfectly normally until you see the balls rolling uphill. When you change the angle of the camera you see that the ramps are not as they appeared. They are actually slanting downhill instead of uphill. It's all about the perspective of course. All of the work for the illusion is performed in a 3D program.
The process to create these illusions is long and difficult. I basically create the design the way it should appear and then create a duplicate of the design that will be the actual physical copy. I manipulate the duplicate in the 3D program so that the ramps ultimately slant down but still match the original layer of the ramps that are aiming up. Once I've created the ramps that slant down, I flatten the shapes, print them out, cut, fold and tape. The camera must be set up in the same position that the camera in the 3D program was set to. The objects that you can create with this technique are unlimited. What happens in our brain when we view an optical illusion? The information gathered by the eye is processed in the brain to create an idea or image that does not match with a physical measurement of the stimulus source.
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