Painting With Light: The Homemade Pixelstick

October 16, 2019 by Sharon Lin 2 Comments

Light painting has long graced the portfolios of long-exposure photographers, but high resolution isn’t usually possible when you’re light painting with human subjects.

This weekend project from [Timmo] uses an ESP8266-based microcontroller and an addressable WS2812-based LED strip to paint words or custom images in thin air. It’s actually based on the Pixelstick, a tool used by professional photographers for setting up animations and photorealism shots. The equipment needed for setting up the light painting sticks runs in the order of hundreds, not to mention the professional camera and lenses needed. Nevertheless, it’s a huge step up from waving around a flashlight with your friends.

The LED Lightpainter takes the Pixelstick a few notches lower for amateur photographers and hobbyists. It directly supports 24-bit BMP, with no conversion needed. Images are stored internally in Flash memory and are uploaded through a web interface. The settings for the number of LEDs, time for the image row, and STA/AP-mode for wireless connections are also set by the web interface. The project uses the Adafruit NeoPixel, ArduinoJson, and Bodmer’s TFT_HX8357 libraries for implementing the BMP drawing code, which also allows for an image preview prior to uploading the code to the microcontroller. Images are drawn from the bottom row to the top, so images have to be transformed before updating to the LED painter.

Some future improvements planned for the project include TFT/OLED support, rainbow or color gradient patterns in the LEDs, and accelerometer or gyroscope support for supporting animation.

There aren’t currently too many galleries of DIY LED-enabled light paintings, but we’d love to see some custom modded light painting approaches in the future.

This isn’t the first LED light stick we’ve seen, if you’re interested in such things.

Hacking Pixmob Bands And Finding A Toolchain

October 15, 2019 by Lewin Day 16 Comments

The Pixmob band is an LED wrist strap, of the type often used at big concerts or other public events. Many have tinkered with the device, but as of yet, nobody was running custom code. It wouldn’t be easy, but [JinGen Lim] got down to work.

The wristbands are given out to concertgoers to create synchronized light shows in the crowd.

A teardown of a 2016 device revealed it consisted of an RGB LED, an IR sensor, a small EEPROM and a coin cell, which were all common parts. Unfortunately, the ABOV MC81F4204 microcontroller was a little more obscure. It’s a part that’s quite hard to find, and uses a proprietary programmer and an ancient IDE.

Searches online proved fruitless, and a working programmer remained outside [JinGen]’s grasp. Undeterred, he decided to simply walk into the company’s Korean headquarters and ask for help. As the part was end-of-life, they were unable to supply a programming device, but happily provided documentation for the chip that wasn’t publicly available. With this in hand, it was possible for [JinGen] to build his own programmer instead.

Booting up a copy of the ABOV IDE, with his newly-built programmer in hand, it was relatively easy to get the chip running custom code. Going the extra mile, [JinGen] even hacked the Arduino IDE to be partially compatible with the platform! A silicon error in the MC81F4204 design bricks the chips after only a few flash rewrites, so its never going to be the most useful platform, but it works nonetheless.

The Pixmob hardware has continued to evolve, and it’s unlikely modern units still use the same chip. Despite this, it’s a great example of what can be achieved by a little sleuthing and asking the right people the right questions. Others have attempted to hack similar products before, found at Disneyland and Coldplay concerts. You won’t catch this author at either, but if you’ve hacked something similar, be sure to reach out on the tip line!

Hacking The IKEA TRÅDFRI LED Power Supply

October 8, 2019 by Donald Papp 22 Comments

Just because something is being actively documented and tampered with by enthusiastic hackers doesn’t mean the information is handily centralized. There can be a lot of value in gathering disparate resources in one place, and that’s exactly what [Trammell Hudson] has done with his resource page for hacking the IKEA TRÅDFRI LED power supply with wireless interface. Schematic teardown, custom firmware images, it’s all there in one convenient spot.

Back in 2017, the IKEA TRÅDFRI hacking scene was centered around the LED light bulbs but as the group of products expanded, the rest of the offerings have also gotten some attention.

Why bother tampering with these units? One reason is to add features, but another is to make them communicate over your own MQTT network. And MQTT is the reason you are only a Raspberry Pi and a trip to IKEA away from the beginnings of a smart home that is under no one’s control or influence but your own.

Building A Cyberpunk Multi-Touch Input Device

October 6, 2019 by Tom Nardi 5 Comments

This multi-touch touch panel built by [thiagesh D] might look like it came from the retro-futuristic worlds of Blade Runner or Alien, but thanks to a detailed build video and a fairly short list of required parts, it could be your next weekend project.

The build starts with a sheet of acrylic, which has a grid pattern etched into it using nothing more exotic than a knife and a ruler. Though if you do have access to some kind of CNC router, this would be a perfect time to break it out. Bare wires are then laid inside the grooves, secured with a healthy application of CA glue, and soldered together to make one large conductive array. This is attached to a capacitive sensor module so it’ll fire off whenever somebody puts a finger on the plastic.

With RGB LED strips added to the edges, you could actually stop here and have yourself a very cool looking illuminated touch sensitive panel. But ultimately, it would just be a glorified button. There’s plenty of interesting applications for such a gadget, but it’s not going to be terribly useful attached to your computer.

To turn this into a viable input device, [thiagesh D] is using a Raspberry Pi and its camera module to track the number and position of fingertips from the other side of the acrylic with Python and OpenCV. His code will even pick up on specific gestures, like a three finger drag which changes the colors of the LEDs accordingly in the video below. The camera’s field of view unfortunately means the box the panel gets mounted to has to be fairly deep, but if recessed into the surface of a desk, we think it could look incredible.

Custom multi-touch panels have been a favorite project of hackers for years now, and we’ve got examples going all the way back to the old black and white days. But larger and more modern incarnations like this one have the potential to change how we interface with technology on a daily basis.

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How To Get Started With Fadecandy And LEDs

October 5, 2019 by Lewin Day 5 Comments

The internet is awash with millions of stunning LED projects, and for that, we are all very thankful. For those outside the hacker/maker matrix, it can be difficult to know how to approach such a build. Never fear, for [Amy Goodchild] has put together a beginner’s guide to building pretty glowables, using Fadecandy and Processing.

Fadecandy is a platform specifically designed to drive WS2812B LEDs for artistic purposes. This allows users to focus on the visual side of things without getting bogged down with the hassle of selecting the right microcontroller and choosing the applicable libraries. It works great in combination with Processing, a piece of software designed for coders experimenting with visual arts. Through a USB link, any graphics drawn by processing can be mapped to the LEDs attached to the Fadecandy controller.

[Amy] does a great job of explaining how to do everything required, from purchasing the right equipment, through wiring everything up, and then getting it all humming along with the correct software. If you’ve ever wanted to build a big flashy project with a ton of LEDs, this would be a great place to start.

We’ve seen Fadecandy put to good use before, too. Video after the break.

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Super Nice LED Lamp Is Super Simple

October 2, 2019 by Lewin Day 19 Comments

If you’re looking for a fancy LED lamp, the Internet can provide in spades. There are all manner of flashy-this and glowing-that, often with wild and impressive designs made with high-end tools. However, when it came time to decorate the apartment, [thebigpotatoe] wanted to build something simple that anyone could attempt. From this, the Super Simple RGB WiFi Lamp was created.

The body of the lamp consists of a plank of wood. It may not sound like much, but thanks to a nifty design, it actually comes out looking remarkably stylish. The plank is fitted with aluminium angle on the back, and a strip of WS2812B LEDs are wrapped around the perimeter of the board. An ESP8266 NodeMCU is fitted to run the show, and powered from a mains supply to allow it to run all day.

The trick here is that the LEDs are mounted on the back of the board, where they are out of direct sight. The light from the LEDs is projected onto the wall the lamp is mounted on, giving a nice smooth effect without requiring any dedicated diffusers. There’s a series of animations coded in, which look great, particularly when the animations wrap around the end of the lamp.

It’s a great addition to the apartment’s feature wall, and goes to show that you don’t need world-beating crafting skills to make a great piece for your home. You can even go all out, and light your whole room this way. Video after the break.

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Interactive LED Dome Glows With The Best Of Them

October 2, 2019 by Lewin Day 2 Comments

With the price and availability of components these days, it’s easier than ever to throw a whole pile of LEDs at a build and get them flashing away. The hard part is doing it well. [Amy Goodchild] is an artist, and has a knack for producing rather beautiful LED projects. The When in Dome installation is no exception.

The build is based around a large geodesic dome, fitted with LED panels that glow and react to the occupants inside. Using the Microsoft Kinect as a sensor enables the dome to map out what’s happening in 3D space, and use this data to guide its animations. WS2812B LED strips were used, in combination with a Fadecandy controller along with Processing. This is a powerful combination which makes designing attractive LED effects easier, without forcing users to go to the effort of writing their own libraries or optimizing their microcontroller code.

For those more interested in the dome itself, you’ll be happy to know that [Amy] doesn’t skimp on the details there either. The build actually started as a commercially available kit, though there’s still plenty of manual cutting, screwing, and painting required. She does an excellent job documenting the dome build through a series of videos, and walks the reader through some of the design decisions she made (and would remake, if given the chance).

People love geodesic domes at the best of times; adding an interactive LED installation just takes things to the next level. We’ve seen them used as greenhouses too, and they make a great hackerspace project as well. Video after the break.

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