This Super Realistic LED Candle Is Smoking Hot

March 15, 2019 by Tom Nardi 14 Comments

Over the last few years, LED candles have become increasingly common; and for good reason. From a distance a decent LED candle is a pretty convincing facsimile for the real thing, providing a low flickering glow without that annoying risk of burning your house down. But there’s something to be said for the experience of a real candle; such as that puff of fragrant smoke you get when you blow one out.

Which is why [Keith] set out on an epic three year quest to build the most realistic LED candle possible, with a specific focus on the features that commercial offerings lack. So not only does it use real wax as a diffuser for the LEDs, but you’re able to “light” it with an actual match. It even ejects a realistic bit of smoke when its microphone detects you’ve blown into it. Ironically, its ability to generate smoke means it doesn’t completely remove the possibility of it setting your house on fire if left unattended, but we suppose that’s the price you pay for authenticity.

As you might have gathered by now, [Keith] is pretty serious about this stuff, and has gone to great lengths to document his candle’s long development process. If you’d care to build a similar candle, his written documentation as well as the video after the break will certainly get you on the right track. He’s even broken the design down into “milestones” of increasing complexity, so for example if you don’t care about the smoking aspect of the candle you can just skip that part of the build.

So what did [Keith] put into his ultimate LED candle? In the most basic form, the electronics consist of a Arduino Pro Mini and a chunk of RGB WS2812B strip holding six LEDs. Add in an IR sensor if you want the candle to be able to detect the presence of a match, and a microphone if you want to be able to blow into the candle to turn it off. Things only get tricky if you want to go full smoke, and let’s be honest, you want to go full smoke.

To safely produce a puff of fragrant smoke, [Keith] is using a coil of 28 gauge wire wrapped around the wick of a “Tiki Torch”, and a beefy enough power supply and MOSFET to get it nice and hot. The wick is injected with his own blend of vegetable glycerin and aromatic oil, and when the coil is fired up it produces an impressive amount of light gray smoke that carries the scent of whatever oil you add. Even if you’re not currently on the hunt for the ultimate electronic candle, it’s a neat little implementation that could be used come Halloween.

You might be surprised to learn that LED candles are a rather popular project within the hacking community. From the exceptionally simple to the exceedingly complex, we’ve seen an impressive array of electronic candles over the years. Perfect for setting the mood when listening to the smooth sounds of the latest Hackaday podcast episode. Continue reading “This Super Realistic LED Candle Is Smoking Hot” →

Twelve Channels Of LEDs Give RRRRGGGGBBBB Light

March 12, 2019 by Brian Benchoff 31 Comments

If you’ve ever searched Mouser or Digikey for LEDs parametrically, you won’t find just one red in your LEDs. You won’t find one green. There is quite literally an entire rainbow of colors of LEDs, and this rainbow goes into infrared and ultraviolet. You can search LEDs by frequency, and an RGEB LED is right at your fingertips. The ‘E’ stands for Emerald, and it’s better than a Bayer filter.

[ayjaym] over on Instructables realized anyone could buy a dozen frequencies of high-power LEDs, and the obvious application for this is to turn it into a tunable light source. The Angstrom is twelve LEDs, all different colors, and all controlled by PWM and piped down a single optical fiber. It’s an RRRRGGGGBBBB LED, ideal for microscopy, forensics, colorimetry, and seeing octoreen.

The heart of this device are twelve 3W star LEDs, with the following wavelengths: 390, 410, 440, 460, 500, 520, 560, 580, 590, 630, 660, and 780 nm. That’s deep red to almost ultra violet, and everything inbetween. These are powered by a 5 V, 60 W power supply, and controlled via a Raspberry Pi with 12 PWM channels in a circuit that’s basically just a bunch of MOSFETs. Proper heatsinking is required.

The impressive part of this build is the optics. A 3D printed mount holds and connects optical fibers and sends them into an optical combiner that is basically just a square acrylic rod. This is output to another optical fiber that will shine on just about anything. A webpage running on a Raspberry Pi sets the PWM channels of all the LEDs, and the resulting output shows up at the end of an optical fiber. It’s great if you want to look at something in a specific frequency of light. It also looks really cool, so that’s a bonus.

RGB Word Clock Doesn’t Skimp On The Features

March 9, 2019 by Tom Nardi 5 Comments

Like most pieces of technology, word clocks seem to be getting better and better every year. As hackers get their hands on better microcontrollers and more capable LED controllers, these builds not only look more polished, but get improved features and functions. Luckily for us, the rise of these advanced modular components means they’re getting easier to build too. For an example of these parallel traits, look no further than VERBIS by [Andrei Erdei].

This colorful word clock is powered by an ESP8266, a 8×8 RGB LED matrix, and a WS2812 RGB LED controller module. [Andrei] used the diminutive ESP-01 which can plug right into the LED controller, and just needs a 3.3 VDC regulator board to complete the very compact electronics package.

To keep the LEDs from interfering with each other, [Andrei] has designed a 3D printed grid which fits over the matrix board. On top of that goes a piece of paper that has the letters printed on it. He mentions that he was able to get good results printing this “stencil” out on an inkjet printer by simply running the same piece of paper through a few times; picking up more black ink each time it went through. Judging by the sharp characters seen in the video after the break, the trick worked well.

With his hardware put together, [Andrei] turned his attention to the software. We really think the project shines here, as his clock not only supports NTP for automatically setting the time over the Internet, but offers a full web interface to control various functions such as the LED colors. You can even change the NTP server and network configuration right from the UI, which is a nice touch compared to just hard coding the values into the code. Even if you don’t use the same hardware, the open source control software is definitely something you should look into if you’re building your own word clock.

We recently covered another easy to build word clock that used an LED matrix and not a whole lot else, but it was quite tiny. This build is a much more reasonable size for a desk, but you’ll probably need to break out the laser cutter if you want to get much bigger.

Continue reading “RGB Word Clock Doesn’t Skimp On The Features” →

Fueled By Jealousy, This Smart Lamp Really Shines

March 6, 2019 by Tom Nardi 8 Comments

As a lover of lava lamps, [Julian Butler] knew when he saw a coworker’s modern LED incarnation of the classic piece of illuminated decor that he had to have one for himself. The only problem was that the Kickstarter for it had long since ended, and they were no longer available. So he did what any good hacker would do: he studied it closely, took a bunch of notes, and built his own version that ended up being even better than the original.

In the three part series on his blog, [Julian] takes us through the design and construction of his take on the Ion Mood Light, which raised over $72,000 back in 2014. The details in the Kickstarter campaign plus his own first-hand observations of the device were enough to give him the high-level summary: the device has a core of RGB LEDs behind a diffuser, and uses some software trickery to pulse out some pleasing effects and patterns. He wasn’t concerned about the Bluetooth or the smartphone application, so all he really needed to do was put some NeoPixel LEDs inside a glass cylinder and he’d be done. Of course, it always sounds easy…

The actual journey to get there, as you might have guessed from the three part series, took awhile. Sourcing the LEDs was easy enough, and using a Fadecandy controller made getting the LEDs to blink out some cool patterns fairly straightforward. But it took [Julian] a bit of experimentation and a few trips to the crafts store before he found a material which would diffuse the LEDs enough for his tastes. Though in the end, he thinks the multiple layers of acrylic he ended up going with actually do a better job of blending the light from the individual LEDs than in the original Ion.

Using the Fadecandy made it easy to drive the LEDs, but he still needed something to provide it with the commands. To that end, he added a decorative base to his LED column that hides a Raspberry Pi and all the lamp’s associated electronics. This includes a microphone which gives his lamp the same sort of sound reactive features that made the Ion so popular. The base does make his lamp a bit bulkier than the original version, but the metallic mesh construction is attractive enough the overall look works.

Of course, you might be wondering how [Julian] got the LEDs to react to sound, or do any of the other gorgeous effects shown off in the video after the break. The software which makes this possible makes up the third and final post in the series, and is really a whole project in itself. The short version of the story is that he used Python and Processing to do real-time computational fluid dynamics, but not before making the necessary adjustments to speed up the simulation on ARM hardware. You know, normal lamp stuff.

This isn’t the first time we’ve seen projects using the Fadecandy board. From creating a Tron inspired desk to building the 5,760 LED “Space Tunnel”, it looks like a great choice if you’ve got a problem that can be solved by the application of a ridiculous number of LEDS.

Continue reading “Fueled By Jealousy, This Smart Lamp Really Shines” →

Tech Imitates Life: Fireflies Make Better Light Bulbs

March 5, 2019 by Al Williams 46 Comments

While we often think we are clever designers, living things often meet or beat the best human designs. It is easy to forget that nature even has living lightbulbs, among them the firefly. Researchers from Penn State decided to compare how fireflies create light and found that they deal with a problem similar to LEDs. The insight may lead to an increase in efficiency for LEDs, which is currently about 50%.

The problem is that some light generated never gets out of the LED (or the firefly’s body). Some light inevitably reflects back into the device. One known mitigation for this is creating a tiny texture pattern on the LED surface which allows more light to escape. These are typically a V-shaped structure etched into the surface. This isn’t news to the firefly, however, which has similar structures on their lanterns as do some other light-generating animals (apparently glowing cockroaches are a thing). However, the organic structures differ from LED textures in an important way.

Continue reading “Tech Imitates Life: Fireflies Make Better Light Bulbs” →

Cylindrical LED Display Comes Full Circle

March 5, 2019 by Tom Nardi 2 Comments

According to [makeTVee], his latest project started out as an experiment to see how well the LED matrix techniques he’s worked with in the past would translate to a cylindrical form factor. We’re going to go ahead and say that not only was the test a success, but that the concept definitely holds promise for displays that are both functional and aesthetically pleasing. This build stops a bit short of being a complete implementation, but what he has so far is very promising and we hope he continues fleshing it out.

A laser cutter was used to create the interlocking segments that make up the display’s frame, but we imagine you could pull off a similar design using 3D printed parts if you don’t have access to a laser. Strips of WS2812 LEDs are mounted along the inside of the cylinder so that each individual LED lines up with the center of a cell. To finish off the outside of the cylinder [makeTVee] used a thin wood veneer called MicroWOOD, which gives the LEDs a nice diffused glow. The wood grain in the veneer also provides an organic touch that keeps the whole thing from looking too sterile.

Of course, a display like this only works if you’ve got software to drive it. To that end, [makeTVee] has used pygame to create a simulator on his computer that shows what the display would look like if it were unrolled and flattened it out. This makes it a lot easier to create content, as you can see the whole display at once. He says the source for the new tool will be coming to GitHub soon, and we’re very interested in taking a look.

If this display looks familiar, it’s probably because a distinctly flatter version of it took the top spot in our “Visualize it with Pi” contest last year.

Continue reading “Cylindrical LED Display Comes Full Circle” →

Teardown Of A Luxury Bluetooth Nightlight

February 28, 2019 by Tom Nardi 4 Comments

If you had asked us yesterday what peak nightlight technology looked like, we might have said one of those LED panels that you stick in the outlet. At least it beats one of those little wimpy light bulbs behind the seashell, anyway. But after looking at a detailed teardown of the “Glow Light” from Casper, we’ve learned a lot about the modern nightlight. Such as the fact that there are adults who not only sleep with nightlights, but are willing to pay $89 USD for one.

But more importantly, as [Tyler Mincey] demonstrates in his excellent look inside one of these high-end nightlights, they are gorgeous pieces of engineering. Even if a nightlight next to the bed has long since gone the way of pajamas with feet on them for you personally, we think you’ll be impressed just how much technology has gone into these softly glowing gadgets.

On the outside they might look like marshmallows, but the insides look far more like what you’d expect from an expensive piece of consumer gear. It’s based on the Nordic nRF52832 Bluetooth SoC which is becoming an increasingly common sight in consumer gadgets, and uses an inertial measurement unit (IMU) to detect when it’s moved or twisted and adjusts the light output accordingly. If you’ve got the disposable income for two of these things, they’ll even synchronize so that twisting one will dim its counterpart.

The teardown that [Tyler] did on the Glow Light is quite frankly one of the best we’ve ever seen, and while it might be a bit light on the gritty technical details, it more than makes up for that with the fantastic pictures that are about as close to actual hardware porn as you can get. The only question we have now is, how long until a hacker replicates this design with a 3D printed enclosure and an ESP?

[Thanks to Adrian for the tip.]