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A Modern Take On The Etch A Sketch

March 20, 2025 by 6 Comments

The Etch A Sketch is a classic children’s toy resembling a picture frame where artwork can be made by turning two knobs attached to a stylus inside the frame. The stylus scrapes off an aluminum powder, creating the image which can then be erased by turning the frame upside down and shaking it, adding the powder back to the display. It’s completely offline and requires no batteries, but in our modern world those two things seem to be more requirements than when the Etch A Sketch was first produced in the 1960s. Enter the Tilt-A-Sketch, a modern version of the classic toy.

Rather than use aluminum powder for the display, the Tilt A Sketch replaces it with an LED matrix and removes the stylus completely. There are no knobs on this device to control the path of the LED either; a inertial measurement unit is able to sense the direction that the toy is tilted while a microcontroller uses that input to light up a series of LEDs corresponding to the direction of tilt. There are a few buttons on the side of the device as well which allow the colors displayed by the LEDs to change, and similar to the original toy the display can be reset by shaking.

The Tilt-A-Sketch was built by [devitoal] as part of an art display which allows the visitors to create their own art. Housed in a laser-cut wooden enclosure the toy does a faithful job of recreating the original. Perhaps unsurprisingly, the Etch A Sketch is a popular platform for various projects that we’ve seen before including original toys modified with robotics to create the artwork and electronic recreations that use LED displays instead in a way similar to this project.

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World’s Smallest Blinky, Now Even Smaller

March 19, 2025 by 29 Comments

Here at Hackaday, it’s a pretty safe bet that putting “World’s smallest” in the title of an article will instantly attract comments claiming that someone else built a far smaller version of the same thing. But that’s OK, because if there’s something smaller than this nearly microscopic LED blinky build, we definitely want to know about it.

The reason behind [Mike Roller]’s build is simple: he wanted to build something smaller than the previous smallest blinky. The 3.2-mm x 2.5-mm footprint of that effort is a tough act to follow, but technology has advanced somewhat in the last seven years, and [Mike] took advantage of that by basing his design on an ATtiny20 microcontroller in a WLCSP package and an 0201 LED, along with a current-limiting resistor and a decoupling capacitor. Powering the project is a 220-μF tantalum capacitor, which at a relatively whopping 3.2 mm x 1.6 mm determines the size of the PCB, which [Mike] insisted on using.

Assembling the project was challenging, to say the least. [Mike] originally tried a laboratory hot plate to reflow the board, but when the magnetic stirrer played havoc with the parts, he switched to a hot-air rework station with a very low airflow. Programming the microcontroller almost seemed like it was more of a challenge; when the pogo pins he was planning to use proved too large for the job he tacked leads made from 38-gauge magnet wire to the board with the aid of a micro hot air tool.

After building version one, [Mike] realized that even smaller components were available, so there’s now a 2.4 mm x 1.5 mm version using an 01005 LED. We suspect there’ll be a version 3.0 soon, though — he mentions that the new TI ultra-small microcontrollers weren’t available yet when he pulled this off, and no doubt he’ll want to take a stab at this again.

DIY Your Own Red Light Therapy Gear

March 18, 2025 by 102 Comments

There are all kinds of expensive beauty treatments on the market — various creams, zappy lasers, and fine mists of heavily-refined chemicals. For [Ruth Amos], a $78,000 LED bed had caught her eye, and she wondered if she could recreate the same functionality on the cheap.

The concept behind [Ruth]’s build is simple enough. Rather than buy a crazy-expensive off-the-shelf beauty product, she decided to just buy equivalent functional components: a bunch of cheap red LEDs. Then, all she had to do was build these into a facemask and loungewear set to get the same supposed skin improving benefits at much lower cost.

[Ruth] started her build with a welding mask, inside which she fitted red LED strips of the correct wavelength for beneficial skin effects. She then did the same with an over-sized tracksuit, lacing it with an array of LED strips to cover as much of the body as possible. While it’s unlikely she was able to achieve the same sort of total body coverage as a full-body red light bed, nor was it particularly comfortable—her design cost a lot less—on the order of $100 or so.

Of course, you might question the light therapy itself. We’re not qualified to say whether or not red LEDs will give you better skin, but it’s not the first time we’ve seen a DIY attempt at light therapy. Continue reading “DIY Your Own Red Light Therapy Gear” →

Cheap Fiber Optic Wand Toy Becomes Tiny Weird Display

February 28, 2025 by 10 Comments

If you’ve ever seen those cheap LED fiber optic wands at the dollar store, you’ve probably just thought of them as a simple novelty. However, as [Ancient] shows us, you can turn them into a surprisingly nifty little display if you’re so inclined.

The build starts by removing the fiber optic bundle from the wand. One end is left as a round bundle. At the other end, the strands are then fed into plastic frames to separate them out individually. After plenty of tedious sorting, the fibers are glued in place in a larger rectangular 3D-printed frame, which holds the fibers in place over a matrix of LEDs. The individual LEDs of the matrix light individual fibers, which carry the light to the round end of the bundle. The result is a tiny little round display driven by a much larger one at the other end.

[Ancient] had hoped to use the set up for a volumetric display build, but found it too fragile to be fit for purpose. Still, it’s interesting to look at nonetheless, and a good demonstration of how fiber optics work in practice. As this display shows, you can have two glass fibers carrying completely different wavelengths of light right next to each other without issue.

We’ve featured some other great fiber optic hacks over the years, like this guide on making your own fiber couplings. Video after the break.

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Powerful Flashlight Gets Active Air Cooling

February 9, 2025 by 16 Comments

LEDs were once little more than weedy little indicators with low light output. Today, they’re absolute powerhouses, efficiently turning a flow of electrons into a searing beam of light. Despite their efficiency, they can still put out a fair whack of heat. Thus, if you’re building a powerful flashlight like [CrazyScience], you might wanna throw some active cooling on there just to keep things happy. Check out the video below.

The build will not be unfamiliar to any casual observer of the modern DIY flashlight scene. It uses a flatpack LED module of great brightness and a wad of 18650 lithium-ion cells to provide the juice to run it. The LED itself is mounted in a 3D-printed frame, which leaves its rear exposed, and a small PC fan is mounted for air cooling. It’s not the most optimized design, as airflow out of the fan is somewhat restricted by the 3D-printed housing, but it’s a lot better than simple passive cooling. It allows the torch to be more compact without requiring a huge heatsink to keep the LED at an acceptable temperature.

The final torch doesn’t have the most ergonomic form factor, but it does work. However, as a learning project for a new maker, it’s a start, and the learning value of building something functional can’t be understated. If your desire for flashlights swerves to the more powerful, we’ve covered those, too. Just be careful out there.

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Tensegrity construction with Adafruit led strands

The Jell-O Glow Tensegrity Toy You Didn’t Know You Needed

January 30, 2025 by 3 Comments

If you’re looking to add a pop of glowing whimsy to your workspace, check out this vibrant jiggly desk toy by [thzinc], who couldn’t resist the allure of Adafruit’s NOODS LED strands. [thzinc]’s fascination with both glowing LEDs and levitating tensegrity designs led to an innovative attempt to defy gravity once again.

The construction’s genius is all about the balance of tension across the flexible LED strands, with three red ‘arms’ and a blue ‘hanger’ arm supporting the central hub. [thzinc]’s early designs faced print failures, but by cleverly reorienting print angles and refining channel designs, he achieved a modular, sturdy structure. Assembly involved careful soldering, tension adjustments, and even a bit of temporary tape magic to perfect the wobbling equilibrium.

But, the result is one to applaud. A delightful, wobbly desk toy with a kind of a Jell-O vibe that dances to your desk’s vibrations while glowing like a mini neon sign. We’ve covered tensegrity constructions in the past, so with a little digging through our archives you’ll be able to find some unique variations to build your own. Be sure to read [thzinc]’s build story before you start. Feel free to combine the best out there, and see what you can bring to the table!

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Interactive LED Matrix Is A Great Way To Learn About Motion Controls

January 21, 2025 by 4 Comments

It’s simple enough to wire up an LED matrix and have it display some pre-programmed routines. What can be more fun is when the LEDs are actually interactive in some regard. [Giulio Pons] achieved this with his interactive LED box, which lets you play with the pixels via motion controls.

The build runs of a Wemos D1 mini, which is a devboard based around the ESP8266 microcontroller. [Giulio] hooked this up to a matrix of WS2812B addressable LEDs in two 32×8 panels, creating a total display of 512 RGB LEDs. The LEDs are driven with the aid of an Adafruit graphics library that lets the whole display be addressed via XY coordinates. For interactivity, [Giulio] added a MPU6050 3-axis gyroscope and accelerometer to the build. Meanwhile, power is via 18650 lithium-ion cells, with the classic old 7805 regulator stepping down their output to a safe voltage. Thanks to the motion sensing abilities of the MPU6050, [Giulio] was able to code animations where the LEDs emulate glowing balls rolling around on a plane.

It’s a simple build, but one that taught [Giulio] all kinds of useful skills—from working with microcontrollers to doing the maths for motion controls. There’s a lot you can do with LED matrixes if you put your mind to it, and if you just start experimenting, you’re almost certain to learn something. Video after the break.

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