Mercurial Light Box Has A Secret Switch

August 17, 2020 by Kristina Panos 14 Comments

Hit up the lighting aisle of any big box hardware store these days and you’ll probably find a variety of Edison bulbs — modern bulbs meant to evoke the bare, complicated tungsten filament bulbs from the early days of electric candlelight. Edison bulbs use filament LEDs, which resemble skinny candles with wicks at both ends and give off a nice light, especially when diffused by acrylic.

This simple light box uses two filament LEDs that float inside on an internal circuit sculpture. [lonesoulsurfer] likes to use old cell phone batteries and USB charging boards in his builds, and that’s exactly what’s inside this box.

Our favorite part of the build elevates this simple light box into a curiosity for those not in the know. It’s controlled with a mercury tilt switch, so all you’d have to do in a power outage is locate the box and turn it upside down, provided it has a charge.

We love elemental switch design around here, like this light box that switches on with salt water.

Helmet Decal Charger Keeps Them Ready To Glow

August 15, 2020 by Kristina Panos 9 Comments

When firefighters are battling a blaze, it’s difficult for them to find each other in the smoky darkness. To help stand out they wear glow-in-the-dark decals on their helmets, but since they spend so much of their down time stowed away in a dark locker, they don’t always have a chance to charge up.

[Bin Sun]’s firefighter friend inspired them to build a portable charging system that can stuff those helmet decals full of photons in a matter of minutes. Although phosphorescent materials will charge in any light, they charge the fastest with ultraviolet light. This uses a pair of UV LED strips controlled by an off-the-shelf programmable timer, and powered with an 18-volt drill battery stepped down to 12 V. The timer makes it easy for [Bin Sun]’s friend to schedule charge times around their shifts, so the battery lasts as long as possible while keeping the decals ready to glow.

We love that [Bin Sun] seems to have thought of everything. The light strips are nestled into 3D-printed holders that also house small magnets. This makes it easy to position the lights on either side of the locker so both the front and back decals soak up the light.

Phosphorescent materials are great as a reusable display medium, especially when they’re designed to look like Nixie tubes.

Abused Hard Drive Becomes POV Clock

August 14, 2020 by Dan Maloney 7 Comments

We all know that there’s not much to do with an old hard drive. Once you render the platters unreadable and perhaps harvest those powerful magnets, there’s not much left of interest. Unless, of course, you turn the whole thing into a persistence-of-vision clock.

At least that’s what [Leo] did when he created “PendoLux”. The clock itself is pretty simple; like any POV project, it just requires a way to move an array of flashing LEDs back and forth rapidly enough that they can trick the eye into seeing a solid image. [Leo] put the read head mechanism of an old HDD into use for that, after stripping the platters and motor out of it first.

The voice coil and magnet of the head arm are left intact, while a 3D-printed arm carrying seven RGB LEDs replaces the old heads. [Leo] added a small spring to return the arm to a neutral position, and used an Arduino to drive the coil and flash the LEDs. Getting the timing just right was a matter of trial and error; he also needed to eschew the standard LED libraries because of his heavy use of interrupts and used direct addressing instead.

POV clocks may have dropped out of style lately — this hard drive POV clock and a CD-ROM version were posted years ago. But [Leo]’s clock is pretty good looking even for a work in progress, so maybe the style will be making a comeback.

Continue reading “Abused Hard Drive Becomes POV Clock” →

RGB LED Shutter Shades

August 5, 2020 by Orlando Hoilett 13 Comments

[splat238] is back at it again with another cool RGB LED display project. We were contemplating whether or not our readers have had enough of these over the last few weeks, but we’ve learned over the years that you can never have too many LED projects.

Instead of making a cool mask like we’ve covered before, [splat238] decided to trick-out some shutter shades. What’s really cool is he used the PCB itself as the frame, similar to another hack we’ve seen, which we’re sure also made his design process that much more convenient.

[splat238] got his boards pre-assembled since it would be really difficult to solder all those LEDs by hand. There are 76 of them in this design. It’s pretty helpful that he walks the reader through how to get the boards assembled, providing information on reliable fabrication and assembly houses that he’s had good experiences with. Pretty solid information if you don’t already have a go-to one-stop-house or have never designed for assembly before.

The glasses use an ESP8266-based microcontroller since it has plenty of space for storing LED patterns and has the potential benefit of including WiFi control in later revisions. However, we think you’ll be pretty happy with simply toggling through the patterns with a simple pushbutton.

The LEDs use a whopping 2.5 A at maximum and rely on an external power bank, so you’ll probably want to be really careful wearing this over an extended period of time. Maybe consider doing a bit of PWM to help reduce power consumption.

Another cool project [splat238]! Keep them coming. Continue reading “RGB LED Shutter Shades” →

Springs And Things Wrap Into A Polyhedron Of Interactive LED Art

August 2, 2020 by Dan Maloney 6 Comments

Any resemblance between The Wobble Sphere and a certain virus making the rounds these days is purely coincidental. Although as yet another project undertaken during the COVID-19 lockdowns, we can see where the inspiration came from.

Wobble Sphere is another work of interactive art from the apparently spring-driven imagination of [Robin Baumgarten], whose Quantum Garden piece graced our pages last year. The earlier, flatter version used a collection of spring door stops — the kind that sound awesome when plucked by a passing foot — each of which is surrounded by a Neopixel ring. The springs act as touch sensors that change the patterns and colors on the LED rings in endlessly fascinating ways.

For Wobble Sphere, [Robin] took the same spring and LED units, broke them into a collection of hexagonal and pentagonal PCBs, and wrapped the whole thing up into a 72-sided polyhedron. There’s some impressive mechanical and electrical engineering involved in the transition from 2D to 3D space, not least of which is solving the problem of how to connect everything while providing pluck-friendly structural support. The former was accomplished with a ton of ribbon cables, while the latter was taken care of with a combination of a 3D-printed skeleton and solder connections between adjacent PCBs. The result is a display that invites touch and rewards it with beautiful patterns of light chasing around the sphere. See it in action in the video after the break.

Lest anyone think springs are the only tool in [Robin]’s box, we mustn’t forget that he once set a knife-wielding Arduino-powered game on an unsuspecting public. Check it out; it’s way more fun than it sounds.

Continue reading “Springs And Things Wrap Into A Polyhedron Of Interactive LED Art” →

Playing The Pixelflut

August 1, 2020 by Kerry Scharfglass 7 Comments

Every hacker gathering needs as many pixels as its hackers can get their hands on. Get a group together and you’ll be blinded by the amount of light on display. (We propose “a blinkenlights” as the taxonomic name for such a group.) At a large gathering, what better way to show of your elite hacking ability than a “competition” over who can paint an LED canvas the best? Enter Pixelflut, the multiplayer drawing canvas.

Pixelflut has been around since at least 2012, but it came to this author’s attention after editor [Jenny List] noted it in her review of SHA 2017. What was that beguiling display behind the central bar? It turns out it was a display driven by a server running Pixelflut. A Pixelflut server exposes a display which can be drawn on by sending commands over the network in an extremely simple protocol. There are just four ASCII commands supported by every server — essentially get pixel, set pixel, screen size, and help — so implementing either a client or server is a snap, and that’s sort of the point.

While the original implementations appear to be written by [defnull] at the link at the top, in some sense Pixelflut is more of a common protocol than an implementation. In a sense, one “plays” one of a variety of Pixelflut minigames. When there is a display in a shared space the game is who can control the most area by drawing the fastest, either by being clever or by consuming as much bandwidth as possible.

Then there is the game of who can write the fastest more battle-hardened server possible in order to handle all that traffic without collapsing. To give a sense of scale, one installation at 36c3 reported that a truly gargantuan 0.5 petabytes of data were spent at a peak of rate of more than 30 gigabits/second, just painting pixels! That’s bound to bog down all but the most lithe server implementation. (“Flut” is “flood” in German.)

While hacker camps may be on pause for the foreseeable future, writing a performant Pixelflut client or server seems like an excellent way to sharpen one’s skills while we wait for their return. For a video example check out the embed after the break. Have a favorite implementation? Tell us about it in the comments!

Continue reading “Playing The Pixelflut” →

A Face Mask That’s Functional And Hacker-Certified

July 27, 2020 by Orlando Hoilett 34 Comments

[splat238] needed a mask for going out in public, but wanted something that fit his personal style a bit better than the cloth masks everyone else was wearing. So, he upcycled his old airsoft mesh mask using an impressive 104 NeoPixels to create his NeoPixel LED Face Mask.

The NeoPixels are based on the popular WS2812b LEDs. These are individually addressable RGB LEDs with a pretty impressive glow. [splat238] purchased a 144 NeoPixel strip to avoid having to solder each of those 104 NeoPixels one-by-one. He cut the 144-LED strip into smaller segments to help fit the LEDs around the mask. He then soldered the power and data lines together so that he could still control the LEDs as if they were one strip and not the several segments he cut them into. He needed a pretty bulky battery pack to power the whole thing. You can imagine how much power 104 RGB LEDs would need to run. We recommend adding a battery protection circuit next time as these LEDs probably draw a hefty amount of current.

He designed his own controller board featuring an ESP8266 microcontroller. Given its sizable internal memory, the ESP8266 makes it easy to store a variety of LED patterns without worrying about running out of programming space. He’s also hoping to add some WiFi features in later revisions of his mask, so the ESP8266 is a no-brainer. Additionally, his controller board features three pushbuttons that allow him to toggle through different LED patterns on the fly.

Cool project [splat238]! Looking forward to the WiFi version.

Continue reading “A Face Mask That’s Functional And Hacker-Certified” →