I think pretty much everyone I know had an Etch-A-Sketch as a kid — or at least, had a friend who did. Ohio Art’s simple but classic design was a well-deserved success, and even served as a “laptop” for Dilbert’s boss.
Of course, one major problem with the Etch-A-Sketch is that it is notoriously difficult to draw anything accurately, unless you have superhuman coordination. Drawing simple horizontal and vertical lines is simple, of course — but drawing circles and similar curves is frustrating and slow, and the results usually end up looking like something a kindergartner with ADHD scribbled while high on Pixie Stick powder.
But this is 2014. We have Arduinos! We have stepper motors! This is a problem that can be solved!
A spiral design, created by an Arduino-powered Etch-A-Sketch. (Click for larger.)
I took a Pocket Etch-A-Sketch that I found in a thrift store, added a pair of gears from a disassembled printer, and mounted it in a 3D printed frame that I designed in Google SketchUp. I then mounted two stepper motors to the frame, and connected them to an Adafruit motor control shield mounted on an Arduino Uno.
The overall hardware setup, showing the custom frame and the Arduino+motor shield combination. (The Arduino Uno is hiding under the motor shield.)
A close-up of the gear mechanism and stepper mounting. (Click for larger.)
Here is the Arduino sketch to run everything. (You’ll need the stepper motor library from Adafruit, as well.)
Here is a video of the AutoSketch doing its thing…
