A drawing robot brain shell! The PolargraphSD Case

I have a confession to make.  I freaking LOVE Sandy Noble’s drawing robot project called Polargraph.  The Polargraph is a very simple to build, simple to operate, open source drawing robot that produces absolutely stunning results.  The entire robot is little more than (a) an Arduino (b) a motor shield or one of Sandy’s awesome Polargraph shields (c) some USB and power cables (d) two motors (e) some printed parts and (f) string, twine, wire, fishing line, or something similar you might have lying around the house.  You may even have many of these parts lying around your work area or hidden in an old printer right now.

Sandy has been constantly improving his Polargraph design, firmware, and software.  The latest iteration of his Polargraph kit includes a custom designed Polargraph Shield which includes a touch screen and operation from an SD card.  Even cooler, he’s using a 3D printed case for the drawing robot brain, featured above.  Having built a basic one myself, I was able to purchase all of the parts for about $100. ¹

Importantly, my MakerBot has enabled me to customize the project and drastically reduce the cost.  Instead of beaded cord and sprockets, I designed and printed my own spools for using fishing line, motor mounts, Arduino mount, and gondola.  What would normally require specially machined parts or the use of a lasercutter, basically just cost me less than $1.00 in plastic. ²

Since the size of your drawing is basically limited only by the size of your canvas and the amount of string you have, the drawing possibilities quickly become staggering.  I was able to take a picture of R2D2, convert them into a single-line-drawing, and draw a three foot tall poster for my daughter.  Not only did she love the picture, she demanded it be put up in her room immediately. ³

If you’re looking for a very beginner friendly project that your kids will absolutely love, you should definitely try this one out. ⁴

1. Had I been a little more patient and even slightly more competent, I could have built it for even less. [↩]
2. And my daughter got to choose the colors.  Which is why the fishing line spools are pink. [↩]
3. A few hours later I began to wonder why she had been so quiet.  It turned out she had spent the entire time coloring the poster in with her markers and crayons. [↩]
4. If you’re interested in such things, I’ve got about 50+ posts on my personal blog about my adventures in building and operating my DrawBot [↩]

Polargraphs are basically really cool drawing robots that have been designed by Sandy Noble, a programmer and artist.  If you’ve never seen one in action, now’s your chance. ¹  Imagine a slow spider crawling around a wall and drawing at the same time.  A microcontroller operates two motors which reel in and out a line which is attached to a pen.  As the pen swings back and forth, it draws in a precise pattern to draw whatever you’ve programmed it to draw.  While very slow, it can cover a really huge drawing area that is pretty much only limited by the amount of string you set it up with and the ink reservoir of your chosen pen.

Thingiverse citizen and prolific printer John Abella recently created a printable gondola to hold the Polargraph’s drawing pen.  The Polargraph requires a bunch of stock off-the-shelf parts and some custom lasercut acrylic and wood bits.  By using a 3D printer to create these assemblies, you’re reducing the need for custom lasercut parts, fasteners, and the assembly time that would normally go into their construction.

Noble’s work reminded me of a similar project by Chicago artist Harvey Moon who showed off his work on “The Drawing Machine” at the recent Maker Faire.  Using a similar cable driven microcontroller controlled² pen drawing machine, Moon’s robot draws the same image differently each time!  Thus, each drawing is a unique little snowflake of arbitrary drawing machine coolness!

There are other equally impressive variations on drawing wall robots in the form of the Hektor, which draws with spray paint cans, the Drawbot by AS220 Labs, and Der Kritzler by Alexander Weber.  Alexander’s website provides a number of links to the websites of similar projects, if you’re looking for more information.

Also, thanks to John Abella for patiently answering my questions and pointing out additional resources!

Untitled by JohnA

This thing brought to you by

1. Cue video! [↩]
2. Redundant?  Perhaps. [↩]