[Tim] got his hands on some APA102 RGB LEDs, which are similar in function to the common WS2812 addressable LEDs seen in many projects we’ve featured. The advantage of APA102 LEDs is that they don’t have the strict timing requirements of the WS2812. These LEDs are controlled with a SPI bus that can be clocked at any arbitrary rate, making them easy to use with pretty much any microcontroller or embedded system.
After working with the LEDs, [Tim] discovered that the LEDs function a bit differently than the datasheet led him to believe. [Tim] controlled a strand of APA102 LEDs with an ATtiny85 and connected a logic analyzer between some of the LEDs. He discovered that the clock signal of the SPI interface isn’t just passed through each LED, it actually looks like it’s inverted on the output. After some investigation, [Tim] found that the clock signal is delayed by a half period (which looks like an inversion) before it’s passed to the next LED. This gives the next LED in the strand enough time for data on the data line to become valid before latching it in.
Since the clock is delayed, [Tim] discovered that additional bits must be clocked as an “end frame” to generate clock signals which propagate the remaining data to the end of the strand. Although the datasheet specifies a 32-bit end frame, this only works for strings of up to 64 LEDs. More bits must be added to the end frame for longer strands, which the datasheet doesn’t even mention. Check out [Tim]’s post for more information, where he walks you through his logic analysis of the APA102 LEDs.
[johannes] writes in with a pretty impressive LED table he built. The table is based around WS2801 serially addressable LEDs which are controlled by a Raspberry Pi. The Pi serves up a node.js-driven web interface developed by [Andrew Munsell] for a room lighting setup. The web interface controls the pattern shown on the display and the animation speed.
[johannes] built a wooden coffee table around the LED matrix, which includes a matte glass top to help diffuse the lighting. An outlet to plug in a laptop and two USB charging ports are panel-mounted on the side of the enclosure, which are a nice touch. The power supply for the LEDs is also inside the enclosure, eliminating the need for an external power brick.
While [johannes] hasn’t written any software of his own yet, he plans on adding music synchronization and visualizations for weather and other data. Check out the video after the break to see the table in action.
Continue reading “A Wooden LED Matrix Coffee Table”
A few years ago, [Marc] had access to a really big, very expensive 3D printer. Daft Punk helmets were – and still are – extremely cool builds, so with a bit of modeling, [Marc] and his friend [Alex] put together a model and printed out a Daft Punk [Thomas] helmet with the intention of turning it into the keystone of a great costume. A few things got in the way, and the [Thomas] helmet was left on a shelf for a few years. Fast forward to a few months ago and [Marc] took up the project again. The result is a 3D printed Daft Punk helmet loaded up with 320 WS2811 LEDs.
The 3D printed helmet was modeled well and printed in polycarbonate, but with any extrusion-based printer, there will be ridges and layers to sand, fill, prime and paint. This task was delegated to another friend, [Shaggy], while [Marc] got busy on the electronics.
The LEDs for the visor and ‘earmuffs’ are WS2811 LEDs, but not the SMD versions we’re so used to seeing. These are 8mm through-hole LEDs mounted in a lasercut piece of acrylic. Control of the LEDs is done with a Teensy 3.1 with [Paul Stoffregen]’s OctoWS2811 library. With the matrix wired up, batteries installed, WiFi capability added, and the helmet painted (not chromed; that will probably happen later, though), [Marc] had a copy of the [Thomas] helmet controllable through an iPhone.
If you’d like to check out more of [Marc]’s work, we posted something on his RGB LED suit and pneumatic Star Trek doors a few years ago.
Continue reading “iPhone-Controlled Daft Punk Helmet”
Regular candles can be awfully boring at times. They can only produce one color and the flicker is so… predictable. They can’t even be controlled by an infrared remote control, not to mention the obvious fire hazard. Now, however, [Jose] has come up with an LED candle that solves all of these problems. (Original link to the project in Spanish.)
The heart of the project is an Arduino Pro Mini, which is especially suited for this project because of its size. [Jose] put the small form-factor microcontroller in the base of a homemade wax enclosure and wired it to a Neopixel WS2812b LED strip. The strip can produce any color, and has some programmed patterns including flicker, fade, rainbow, and fire.
The artificial candle is controlled with an infrared remote control, and all of the code for the project is available on the project site if you want to build your own. [Jose] has been featured here before for his innovative Arduino-driven RGB lighting projects, and this is another great project which builds on that theme!
[Saurabh] wanted a quick project to demonstrate how easy it can be to build devices that are voice controlled. His latest Instructable does just that using an Arduino and Visual Basic .Net.
[Saurabh] decided to build a voice controlled lamp. He knew he wanted it to change colors as well as be energy-efficient. It also had to be easy to control. The obvious choice was to use an RGB LED. The LED on its own wouldn’t be very interesting. He needed something to diffuse the light, like a lampshade. [Saurabh] decided to start with an empty glass jar. He filled the jar with gel wax, which provides a nice surface to diffuse the light.
The RGB LED was mounted underneath the jar’s screw-on cover. [Saurabh] soldered a 220 ohm current limiting resistor to each of the three anodes of the LED. A hole was drilled in the cap so he’d have a place to run the wires. The LED was then hooked up to an Arduino Leonardo.
The Arduino sketch has several built-in functions to set all of the colors, and also fade. [Saurabh] then wrote a control interface using Visual Basic .Net. The interface allows you to directly manipulate the lamp, but it also has built-in voice recognition functionality. This allows [Saurabh] to use his voice to change the color of the lamp, turn it off, or initiate a fading routing. You can watch a video demonstration of the voice controls below. Continue reading “Voice Controlled RGB LED Lamp”
We don’t think we’ve seen an Infinity Mirror Clock before, but we love this new twist on an old favorite. Different colors distinguish between seconds, minutes and hours, and an additional IR sensor detects when someone is directly in front of the clock and switches the LEDs off, allowing it to be used as a normal mirror. This build is the work of [Dushyant Ahuja], who is no stranger to hacking together clocks out of LEDs. You can tell how much progress he’s made with the mirror clock by taking a glance at his first project, which is an impressive creation held together by jumbles of wire and some glue.
[Dushyant] has stepped up his game for his new clock, attaching an LED strip along the inside of a circular frame to fashion the infinity mirror effect. The lights receive a signal from an attached homemade Arduino board, which is also connected to a real-time clock (RTC) module to keep time and to a Bluetooth module, which allows [Dushyant] to program the clock wirelessly rather than having to drag out some cords if the clock ever needs an adjustment.
Stick around after the jump for a quick demonstration video. The lights are dazzling to watch; [Dushyant] inserted a stainless steel plate at the center of the circle to reflect the outer rim of LEDs. After a quick rainbow effect, it looks like the mirror enters clock mode. See if you can figure out what time it is. For a more step-by-step overview of this project, swing by his Instructables page.
Continue reading “Infinity Mirror Clock: There’s a Time Joke There Somewhere”
[Joakim] has built a clock that spells out the time in words. Wait a second – word clock, what is this, 2009? Word clocks are one of those projects that have become timeless. When we see a build that stands out, we make sure to write it up. [Joakim’s] clock is special for a number of reasons. The time is spelled out in Norwegian, and since the clock is a birthday gift for [Daniel], [Joakim] added
the his full name to the clock’s repertoire.
One of the hard parts of word clock design is controlling light spill. [Joakim] used a simple 3D printed frame to box each LED in. This keeps the spill under control and makes everything easier to read. The RGB LED’s [Joakim] used are also a bit different from the norm. Rather than the WS2812 Neopixel, [Joakim] used LPD8806 LED strips. On the controller side [Joakim] may have gone a bit overboard in his choice of an Arduino Yun, but he does put the ATmega328 and Embedded Linux machine to good use.
The real magic happens at boot. [Daniel’s] name lights up in red, with various letters going green as each step completes. A green ‘D’ indicates an IP address was obtained from the router’s DHCP server. ‘N’ switches to green when four NTP servers have been contacted, and the Linux processor is reasonably sure it has the correct time. The last letter to change will be the ‘E’, which reports ambient light.
[Joakim] added a web interface to trigger his new features, such as a rainbow color palette, or the ability to show minutes by changing the color of the letters K,L,O,K. The final result is a slick package, which definitely brings a 2009 era design up to 2014 standards!