While largely supplanted by more modern forms of printing, dot matrix printers still have their fans. Few, however, are more dedicated than Nikodem Bartnik, who constructed his own model that pulls paper up to 55cm wide and as long as he needs under a gantry that stamps each pixel with a marker.

The device is controlled via an Arduino Uno, which takes input from a Processing sketch running on a computer to obtain the image to be printed.

It uses a pair of stepper motors to advance the paper, as well as a third to position the marker to be stamped. A servo motor pushes the marker down as needed, producing a print that, as seen at 5:15 in the video below, is accurate and stylishly pixellated.

While some fall asleep nearly immediately with no assistance, others need the drone of a fan or a dedicated noisemaker to help them relax. The Fall Asleep Device, also known as “FADing,” by Youz takes a different approach. FADing shines an LED onto the ceiling out via a piece of acrylic, so that you can use it whether you like to sleep on your back or side.

An Arduino Nano controls the nicely-shaped wooden unit, and causes light to fade in and out at a pace that decreases from 11 to 6 pulses per minute, prompting you to regulate and relax your breathing accordingly.

After being started by a button below, FADing is kept on by a relay until it finishes, meaning it uses no power in standby. You can check it out in the video below, and find build instructions and code in Youz’s write-up.

With CNC machines, getting the best results depends on knowing how fast your tool is moving relative to the workpiece. But entry-level CNC routers don’t often include a spindle tachometer, forcing the operator to basically guess at the speed. This DIY optical spindle tach aims to fix that, and has a few nice construction tips to boot.

The CNC router in question is the popular Sienci, and the 3D-printed brackets for the photodiode and LED are somewhat specific for that machine. But [tmbarbour] has included STL files in his exhaustively detailed write-up, so modifying them to fit another machine should be easy. The sensor hangs down just far enough to watch a reflector on one of the flats of the collet nut; we’d worry about the reflector surviving tool changes, but it’s just a piece of shiny tape that’s easily replaced.  The sensor feeds into a DIO pin on a Nano, and a small OLED display shows a digital readout along with an analog gauge. The display update speed is decent — not too laggy. Impressive build overall, and we like the idea of using a piece of PLA filament as a rivet to hold the diodes into the sensor arm.

Want to measure machine speed but don’t have a 3D printer? No worries — a 2D-printed color-shifting tach can work too.

When you play a video game, the controls are normally a compromise between what you have available (a keyboard/mouse) and the actions you’re trying to convey. This, however, wasn’t good enough for Kerbal Space Program enthusiast Hugopeeters, who instead of accepting this limited input method, designed a new control panel using an Arduino Uno as its heart.

Notable features of his build include dual joysticks, a throttle slider, a multi-purpose LCD display, LED bars for fuel gauges, and a beautifully laser-cut enclosure.

Want to construct your own? Find more details on the project in Hugopeeters’ write-up, as well as the Arduino code he used and the KSP plugin necessary to interact with his new hardware.

While video games have grown more and more complex over the last few decades, TWANG takes things in the opposite direction as an Arduino Mega-based 1D dungeon crawler consisting of an RGB LED strip.

The player—a dot—is controlled via an accelerometer mounted to a door spring used as a joystick. With it, the player can move forwards, backwards, and attack by “twanging” the spring to make it vibrate. The LEDs display a wide array of colors, including representations of glowing lava, water, and player disintegration when a mistake is made.

TWANG is inspired by the Line Wobbler game from Robin Baumgarten, and beautifully implemented as shown in the video below by Barton Dring. Code for the build can be found here, and 3D print files for the housing/joystick are also available.

A delightful version of a clever one-dimensional game has been made by [Critters] which he calls TWANG! because the joystick is made from a spring doorstop with an accelerometer in the tip. The game itself is played out on an RGB LED strip. As a result, the game world, the player, goal, and enemies are all represented on a single line of LEDs.

How can a dungeon crawler game be represented in 1D, and how is this unusual game played? The goal is for the player (a green dot) to reach the goal (a blue dot) to advance to the next level. Making this more difficult are enemies (red dots) which move in different ways. The joystick is moved left or right to advance the player’s blue dot left or right, and the player can attack with a “twang” motion of the joystick, which eliminates nearby enemies. By playing with brightness and color, a surprising amount of gameplay can be jammed into a one-dimensional display!

Code for TWANG! is on github and models for 3D printing the physical pieces are on Thingiverse. The video (embedded below) focuses mainly on the development process, but does have the gameplay elements explained as well and demonstrates some slick animations and sharp feedback.

Using a spring doorstop as a controller is neat as heck as well as intuitive, but possibly not quite as intuitive as using an actual car as a video game controller.

Infinity mirrors, which make light appear to stretch to infinity by bouncing light between two mirrors, are incredible to observe. Hacker “Evocate” decided to go the extra mile and not only illuminate the inside of his mirror arrangement, but used an Arduino Uno and a sound sensor to enable it to react to sound.

In addition to this sound sensitivity, a Bluetooth app controls color and brightness, allowing him to customize the device on the fly.

The mirror also has a built-in microphone which detects sound/music and reacts accordingly by generating eye-catching light strobes on the beat of the music! Simply start up the app, connect to Bluetooth and see the magic happen!

If you’d like to build your own, full instructions along with Arduino and app code are available here. Or you can simply check it out in action below!

If you have even the most passing interest in space and what it takes to get there, you’ve probably already played Kerbal Space Program (KSP). If you haven’t, then you should set aside about ten hours today to go check that out real quick. Don’t worry, Hackaday will still be here when you get back. Right now you need to focus on getting those rockets built and establishing a network of communication satellites so you can get out of low orbit.

For those of you who’ve played the game (or are joining us again after playing KSP for the prescribed 10, 12, 16 hours), you’ll know that the humble computer keyboard is not very well suited to jaunts through space. You really want a joystick and throttle at the absolute minimum for accurate maneuvers, but even you’ll be spending plenty of time back on the keyboard to operate the craft’s various systems. If you want the ultimate KSP control setup, you’ll need to follow in the footsteps of [Hugo Peeters] and build your own. Luckily for us, he’s written up an exceptionally well detailed guide on building KSP controllers that should prove useful even if you don’t want to clone his.

At the most basic level, building a KSP controller consists of hooking a bunch of switches and buttons to a microcontroller such as the Arduino or Teensy, and converting those to USB HID key presses that the game understands. This works fine up to a point, but is limited because it’s only a one-way method of communication. For his controller, [Hugo] forked KSPSerialIO, a plugin for KSP that allows bidirectional communication between the game and your controller, enabling things like digital readouts of speed and fuel levels on the controller’s panel.

Once the logistics of how you’ll talk to the game are settled, the rest is really up to the individual. The first step in building your own KSP controller is deciding what you want it to do. Are you looking to fly planes? Control a rover? Maybe you just want a master control panel for your space station. There’s a whole lot of things you can build in KSP, and the layout, inputs, and displays on your controller should ideally reflect your play style.

[Hugo] went with a fairly general purpose panel, but did spend quite a bit of extra time to get some slick LED bar graphs hooked up to display resource levels of different systems on his craft. That’s an extra step that isn’t strictly required for a build like this, but once you see it, you’re going to have a hard time not wanting to include it on your own panel. He also went through the expense of having the panel and case professionally laser cut and etched, which definitely gives it a polished feel.

We’ve covered quite a number of custom KSP controllers here at Hackaday. The overlap between KSP players and hackers seems unusually high, but of course a game that lets you build and fly contraptions of your own design does sound like something that would be right up our alley.

Rather than buying a coffee table, Marija from Creativity Hero decided to build her own, adding an array of 45 programmable LEDs on top of a pine base.

An Arduino Mega is used to take input from 45 sensors corresponding to each LED in a grid made with MDF baffles, and commands each light to change colors based on whether something is placed on that square section. The on/off colors used can be selected via a Bluetooth smartphone app, allowing you to customize the furniture to your liking.

This unique LED coffee table can create beautiful atmosphere and will be a real focal point in my living room. I wanted to make a simple design with some interesting features that will take my room to a whole new level. It is controlled via a custom-made Android application, so I can easily change the reactive color, or the background color, and I can even adjust the brightness.

You can find full details on the project here, as well as the tools and parts you’ll need.

Like a lot of 16-year-olds, [Maxime Coutée] wanted an Oculus Rift. Unlike a lot of 16-year-olds, [Maxime] and friends [Gabriel] and [Jonas] built one themselves for about a hundred bucks and posted it on GitHub. We’ll admit that at 16 we weren’t throwing around words like quaternions and antiderivatives, so we were duly impressed.

Before you assume this is just a box to put a phone in like a Google Cardboard, take a look at the bill of materials: an Arduino Due, a 2K LCD screen, a Fresnel lens, and an accelerometer/gyro. The team notes that the screen is what will push the price unpredictably, but they got by for about a hundred euro. At the current exchange rate, if you add up all the parts, they went a little over $100, but they were still under $150 assuming you have a 3D printer to print the mechanical parts.

The system uses two custom libraries that you could use even if you wanted a slightly different project. FastVR creates 3D virtual reality using Unity and WRMHL allows Unity to communicate with an Arduino. Both of these are on the team’s GitHub page, as well.

There was one other member of the team, their math teacher [Jerome Dieudonne] who they call [Sensei]. According to [Jerome] he is “… the theoretician of the team. I teach them math and I help them solving algorithm issues.” He must be very proud and we always applaud when someone takes the time to share what they know with students.

We don’t know what’s next for this group, but we will be keeping an eye on them to see what’s next. Maybe they’ll work on smell-o-vision.