The original Illumicon drawing machine used gears to move a pinpoint LED light in complex patterns that were recorder by a camera mounted overhead to produce images such as the following:

While it worked fine, it was large, heavy, temperamental and the woods gears were hard to make. Fortunately, A great improvement was just around the corner.


The Hypno-Lumigraph Drawing Machine:


One day while working with a Hypnograph drawing machine (by Thinkfun, sold on Amazon.com for $30) I realized it had all the parts for making an improved Illumicon, and so the Hypno-Lumigraph drawing machine was born.


I mounted a 10 RPM gear motor ($25 from servocity.com) on a wood base, extended the shaft up through a hole drilled in the central 60-toothed gear and mounted a plywood disk covered with steel strapping on the disk. The central gear is screwed to the top of the wood base. When the motor is connected to a battery, the plywood disk rotate around the central gear. Wood bars have plastic gears from the Hypnograph attached to them with a free moving shaft with a gear attached at both ends. Magnets on the bars hold them to the metal strapping on the plywood disk. The lower gear meshes with the fixed central main gear and as the motor turns the plywood disk, this lower gear drives the upper gear. The shafts are 5/16ths bolts with the heads cut off.

The upper gears just act as holders for the plastic studs from the Hypnograph that drive the arm on which a pinpoint LED light (the silver cylinder being pointed at) is placed. Gears can be changed to create any motion desired, which is captured as with the illumicon in a darkened room with a camera positioned overhead, such as the following:

As interesting as this image looks, it has two problems. Stray light from the LED shines on the lightly colored base, which shows up as a blue background disk in the image. More seriously, a close examination of the lines shows that they have many wiggles. Fortunately, both problems were easily fixed.


Painting everything the camera sees black eliminated the background problem. The wiggles were caused by the plastic drive arm flexing and rocking on the drive studs. Gluing a stiffening piece of wood to the drive arm got rid of the flexure. Gluing 1-inch diameter washers to the drive studs increased the diameter of the shoulder on with the drive arm rests and stopped the rocking. I also reduced the height of the LED so that any remaining rocking wasn't as obvious. Now the lines are smooth and there is no background ghost light.

Here's the result:


Changing the color of the LED makes this simple spirograph-like trace really pop.


Switching to green brightens this tri-loop trace. Notice that where the light is moving slower, the exposure is brighter. This produces a textured effect that pen-on-paper drawing machines can't produce.

Because the Hypnograph comes with two dozen gears, the Hypno-Lumigraph drawing machine can be configured to create hundreds if not thousands of fascinating traces.

To watch the Hypno-Lumigraph in action, please click on the following link:




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