LED Jewelry Makes Neat Use Of Brass

May 13, 2019 by Lewin Day 7 Comments

Wearable electronics can be both fun and fashionable. However, there are certain challenges involved in neatly integrating electronic components in a way that is both functional and comfortable for the wearer. In this vein, [Jiri Praus] has managed to create some glowing earrings that are remarkably simple to boot.

The body of the earring also acts as the conductor and battery holder, all in one.

The earrings start out with brass rod, bent with pliers and soldered at the ends. By following a paper template, it’s possible to get neat and accurate bends by hand, which is necessary to make a matching pair. Through careful design, the brass rods are soldered to the LEDs, and more rod is then used to create an integrated holder for a coin cell battery, which powers the lights.

Thanks to [Jiri]’s smart designs — which we’ve featured before in the form of a blooming wireframe tulip — no wires are needed. The brass rods which make up the body of the jewelry also act as the conductors to pass current to the LEDs. The internal resistance of the coin cell battery also eliminates the need for an in-line resistor. In combination, this serves to create a simple and attractive finished product that should shine for several hours.

We’ve seen other LED earring designs before, too. There are plenty of ways to experiment with glowing jewelry, and if you’ve done something novel, be sure to let us know.

Lots Of Blinky! ESP32 Drives 20,000 WS2812 LEDs

May 7, 2019 by Bob Baddeley 17 Comments

20,000 LEDs sounds like an amazing amount of blink. When we start to consider the process of putting together 20,000 of anything, and then controlling them all with a small piece of electronics the size of a postage stamp, we get a little bit dizzy. Continue reading “Lots Of Blinky! ESP32 Drives 20,000 WS2812 LEDs” →

Getting That Neon Sign Look Without All The Hassle

May 6, 2019 by Ted Yapo 27 Comments

We all love the look of neon signage, but the between the glassblowing equipment, gas cylinders, high voltage, and the associated skill set, it’s not practical for everyone. Luckily, these days there’s a good alternative: “neon” flexible LED strips. This is the approach [Benni] recently took in making a large logo display, and the results speak for themselves.

[Benni] sourced the strips from AliExpress. They’re 8 mm wide and can be cut to length in multiples of 4.2 cm. Inside, there are strips of RGB LEDs, making the displays that much more versatile than actual neon. Covering the LEDs is a silicone diffuser strip that completes the illusion of a neon tube. The flexibility of the strips make them easy to bend into different shapes, but also mean a solid substrate of some sort is required to make them hold their shape. In [Benni]’s case, he used a metal frame to which he glued the strips with cyanoacrylate adhesive. He used zip ties to clamp the strips in place while the glue cured, and the fact that he clipped the tails of the zip ties is a testament to his detail-oriented nature; we would probably have left them on. All of the attention payed off though because the end product looks awesome. The finishing touches are supplied by some 3D-printed bezels carrying acrylic diffuser panels and traditional LED strips for the eyes, plus a DMX LED controller.

We’ve seen [Benni]’s work before, like this slick USB rotary encoder peripheral, and like that time, there’s a video which really shows off the project. Have a look, after the jump.

Continue reading “Getting That Neon Sign Look Without All The Hassle” →

LED Matrix And A Phototransistor Make A Reverse Camera

May 6, 2019 by Dan Maloney 12 Comments

A digital camera has an array of sensors that captures light reflected or transmitted onto it. This build is something closer to a reverse camera – a single sensor that makes images on a matrix of LEDs. And we think it’s pretty neat.

We have to admit to being a little confused by [marciot]’s LED matrix scanner when we first stumbled upon it. From the video below we thought that the LEDs in the matrix were being used both to detect incident light and as a display. We’ve seen LEDs used as photodiodes before, so such a contraption could work, but that’s not what’s going on here. A phototransistor is wired to an Arduino Uno and positioned above a 32×32 RGB LED matrix. A scanning routine rasters over the LEDs in the matrix while the sensor watches, and then the program turns on the LEDs that the sensor saw during the scan. Positioned far above the matrix, a large disc of light results, making it look like the phototransistor is beaming light down onto the matrix. The effect is reinforced by placing something between the sensor and the matrix, which casts a virtual shadow. Used close to the LEDs the sensor acts more like a light pen.

It’s a cool effect and it looks like a fun project to throw together. Refresh time could perhaps be a bit snappier, though; maybe an ESP32 could help with that.

Continue reading “LED Matrix And A Phototransistor Make A Reverse Camera” →

Star Wars Electrostaff Effect, Done With Spinning LEDs

May 4, 2019 by Donald Papp 10 Comments

[Bithead] wanted to make a prop replica of an Electrostaff from Star Wars, but wasn’t sure how best to create the “crackling arcs of energy” effect at the business ends. After a few false starts, he decided to leverage the persistence of vision effect by spinning LEDs in more than one axis to create helical arcs of light and it seems that this method has some potential.

Many multi-axis persistence of vision devices use a component called a slip ring in order to maintain electrical connections across rotating parts, but [Bithead] had a simpler plan: 3D print a frame and give each axis its own battery. No centralized power source means a quicker prototype without any specialized parts, and therefore a faster proof of concept to test the idea.

[Bithead] already has improvements planned for a new version, but you can see the current prototype in action in the short video embedded after the break.

Continue reading “Star Wars Electrostaff Effect, Done With Spinning LEDs” →

Utterly Precise Light Painting, Thanks To CNC And Stop Motion

May 4, 2019 by Donald Papp 13 Comments

Light painting is the process of moving a light while taking a long-exposure photograph, which creates a sort of drawing from the path of the light source. It’s been done in one way or another since at least the early-to-mid 1900s, but modern hardware and methods have allowed for all kinds of new spins on this old idea. [Josh Sheldon] demonstrates just how true this is with the light painting he did for a gum ad, showing what’s possible with a single multicolor LED under CNC control combined with stop-motion animation techniques. The rest of the magic comes from the software. [Josh] designs the animations in Blender, and the paths are then exported and used as the instructions for his self-made Light Painting Machine. The machine therefore recreates the original animation with lights and camera and not a single computer-generated graphic.

[Josh] is no stranger to light painting in this way. We’ve seen his fantastic machine at work before and we’re glad he shared the details behind his latest work. Embedded below is a concise video that shows the whole process, but if you’re in a hurry and just want to see the end product, here’s a shortcut to the results.

For those of you who would like to know more, there are plenty of details on [Josh]’s Light Painting Machine on GitHub along with a more in-depth description of the workflow and software, so check it out.

Continue reading “Utterly Precise Light Painting, Thanks To CNC And Stop Motion” →

How-To: Mapping Server Hits With ESP8266 And WS2812

May 2, 2019 by Pedro Umbelino 17 Comments

It has never been easier to build displays for custom data visualization than it is right now. I just finished one for my office — as a security researcher I wanted a physical map that will show me from where on the planet my server is being attacked. But the same fabrication techniques, hardware, and network resources can be put to work for just about any other purpose. If you’re new to hardware, this is an easy to follow guide. If you’re new to server-side code, maybe you’ll find it equally interesting.

I used an ESP8266 module with a small 128×32 pixel OLED display connected via an SSD1306 controller. The map itself doesn’t have to be very accurate, roughly knowing the country would suffice, as it was more a decorative piece than a functional one. It’s a good excuse to put the 5 meter WS2812B LED strip I had on the shelf to use.

The project itself can be roughly divided into 3 parts:

Physical and hardware build
ESP8266 firmware
Server-side code

It’s a relatively simple build that one can do over a weekend. It mashes together LED strips, ESP8266 wifi, OLED displays, server-side code, python, geoip location, scapy, and so on… you know, fun stuff.

Continue reading “How-To: Mapping Server Hits With ESP8266 And WS2812” →