Instead of scraping aluminum powder off of plastic by driving a stylus on an x-y gantry with a pair of knobs, this bad boy uses rotary encoders to move the cursor around and put down squares of colored light. The familiar movements are there — the left knob moves the cursor left and right, and the right knob moves it up and down. But this wouldn’t be a 21st century toy without newfangled features. Push the left encoder down and it cycles through eight color choices, or push the right one down to go through them backwards. We hope one of the colors is setting it back to darkness in case you screw up. And while we’re dreaming up improvements, it would be awesome to add an accelerometer so you could shake it clear like a standard Etch-a-Sketch.
Inside the requisite red enclosure with white knobs are an Arduino Nano and a 16×16 RGB LED matrix. The enclosure is four sheets of 6mm MDF glued together, and we like the use of protoboard to distribute GND and 5 V in the name of keeping the thing slim.
The Etch-A-Sketch was a toy that demanded mastery. Some grew capable of creating masterful artworks, while others struggled to do more than a jumbled mess of angry, angular lines. The inherent limitations of being able to only draw a singular, connected line are all part of the fun, of course, and [gatoninja236] recreated that in a modern, LED form.
The build uses a Raspberry Pi to run the show, with a 64×64 LED matrix hooked up to the GPIO pins serving as a display. Two encoders are used to recreate the famous Etch-A-Sketch interface, hooked up to an Arduino Nano that then communicates encoder data to the Pi over I2C, due to the limited GPIOs available. There’s also an MPU6050 accelerometer board, used to enable the intuitive shake-to-clear functionality.
Considering one of the biggest draws of the original Etch a Sketch was how simple it was, it’s always interesting to see the incredible lengths folks will go to recreate that low-tech experience with modern hardware. A perfect example is this giant wall mounted rendition of the iconic art toy created by [Ben Bernstein]. With a Raspberry Pi and some custom electronics onboard, it can even do its own drawing while you sit back and watch.
At a high level, what we’re seeing here is a standard Samsung LCD TV with a 3D printed Etch a Sketch shell mounted on top of it. That alone would be a pretty neat project, and had [Ben] just thrown some videos of designs getting sketched out onto the display, he could have achieved a similar end result with a lot less work. But where’s the fun in that?
To make his jumbo Etch a Sketch functional, [Ben] spent more than a year developing the hardware and software necessary to read the user input from the two large 3D printed knobs mounted under the TV. The knobs are connected to stepper motors with custom PCBs mounted to their backs that hold a A4988 driver chip as well as a AS5600 absolute magnetic rotary encoder. This solution allows the Raspberry Pi to not only read the rotation of the knobs when a person is using the Etch a Sketch interactively, but spin them realistically when the software takes over and starts doing an autonomous drawing.
Several Python scripts pull all the various pieces of hardware together and produce the final user interface. The software [Ben] wrote can take an image and generate paths that the Etch a Sketch can use to realistically draw it. The points that the line is to pass through, as well as variables that control knob rotation and pointer speed, are saved into a JSON file so they can easily be loaded later. Towards the end of the Imgur gallery [Ben] has created for this project, you can see the software working its way through a few example sketches.
It happens to everyone. You get your hands on an Etch-A-Sketch for the first time, and armed with the knowledge of how it works, you’re sure you can draw things other than rectangles and staircases. And then you find out the awful truth: you are not as precise as you think you are, and if you’re [QuintBUILDS], the circles you try to draw look like lemons, potatoes, or microbes.
Most importantly, you can still pick it up and shake it to clear the screen, a feature sorely lacking in many of the auto-sketchers we scratch about. And if you’re not fully satisfied by this hack, be sure to check out the stop-motion video after the break that turns this baby into a touch-screen video player for Flatlanders.
Turn it over and you’ll find a Raspberry Pi 3 and a CNC hat. The knobs are belt-driven from a pair of NEMA-17 size stepper motors that interface to the knobs with tight-fitting pulleys. Power comes from four 18650s, and is metered by a battery management board that provides both overcharge and drain protection. At some point in the future, [QuintBUILDS] plans to move to a battery pack, because the cell holder is electrically unstable.
We love the welded frame and acrylic enclosure because they make the thing sturdy and portable. Also, we’re suckers for see-through enclosures. They’re clearly superior if you want to do what [QuintBUILDS] did and take it to an elementary school science fair to show the kids just how cool science can be if you stick with it.
If you don’t think motorized Etch-A-Sketches can be useful, maybe you just haven’t seen this clock build yet.
For better or for worse, the tech world has fully committed to pushing as many of their products into “The Cloud” as possible. Of course, readers of Hackaday see right through the corporate buzzwords. It’s all just a fancy way of saying you have to poke some server over the Internet every time you want to use the service. In a way, [Matt Welsh] has perfectly demonstrated this concept with Escher. It’s a normal Etch-a-Sketch, but since somebody else owns it and you’ve got to have an active Internet connection to use it, that makes it an honorary citizen of the Cloud.
Escher takes the form of a 3D printed mount and replacement knobs for the classic drawing toy that allow two NEMA 17 steppers to stand in for human hands. Thanks to the clever design, [Matt] can easily pull the Etch-a-Sketch out and use it the old fashioned way, though admittedly the ergonomics of holding onto the geared knobs might take a little getting used to. But who wants to use their hands, anyway?
In terms of the electronics, the star of the show is the the Adafruit Feather HUZZAH32 development board, paired with a motor controller that can provide 12 V to the steppers. [Matt] even went through the trouble of making a custom voltage regulator PCB that steps down the stepper’s voltage to 5 V for the Feather. Totally unnecessary, just how we like it.
For the software folks in the audience, [Matt] goes into considerable detail about how he got his hardware talking to the web with Google Firebase. Even if the Internet of Sketches doesn’t quite tickle your fancy, we imagine his deep-dive on pushing G-Code files from the browser into the Feather will surely be of interest.
Hackaday Editors Elliot Williams and Mike Szczys geek out over the latest hacks. This week we saw a couple of clever CNC builds that leverage a great ESP32 port of GRBL. The lemonade-pitcher-based submarine project is everything you thought couldn’t work in an underwater ROV. Amazon’s newest Dot has its warranty voided to show off what 22 pounds gets you these days. And there’s a great tutorial on debugging circuits that grew out of a Fail of the Week. Plus, we get the wind knocked out of us with an ambitious launch schedule for airless automotive tires, and commiserate over the confusing world of USB-C.
Take a look at the links below if you want to follow along, and as always tell us what you think about this episode in the comments!
Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!
Taking a selfie before the modern smartphone era was a true endeavor. Flip phones didn’t have forward-facing cameras, and if you want to go really far back to the days of film cameras, you needed to set a timer on your camera and hope, or get a physical remote shutter. You could also try and create a self portrait on an Etch a Sketch, too, but this would take a lot of time and artistic skill. Luckily in the modern world, we can bring some of this old technology into the future and add a robot to create interesting retro selfies – without needing to be an artist.
Once the picture is taken, the ESP32 at the heart of the build handles the image processing and then drawing the image on the Etch a Sketch. The robot needs a black and white image to draw, and an algorithm for doing it without “lifting” the drawing tool, and these tasks stretch the capabilities of such a small processor. It takes some time to work, but in the end the results speak for themselves.
The final project is definitely worth looking for, if not for the interesting ESP32-controlled robot than for the image processing algorithim implementation. The ESP32 is a truly versatile platform, though, and is useful for building almost anything.