Custom Bedroom Lighting Controlled By Alexa

August 2, 2025 by Lewin Day 1 Comment

[Arkandas] had a problem. They liked reading in bed, but their bedroom lamps weren’t cutting it—either too bright and direct, or too dim and diffuse. The solution was custom lighting, and a new project began.

The concept was simple—build a custom controller for a set of addressable LED lighting strips that would be installed in the bedroom. Specifically, in the headboard of the bed, providing controllable light directly where it was needed. The strips themselves were installed in aluminum channel with plastic diffusers to give a nice smooth light. [Arkandas] then tasked an ESP32 to control the strips, using the FastLED library to work with WS2812B LEDs, and also the Adafruit NeoPixel library for using SK6812 LEDs and their extra white channel. The ESP32 was set up to provide a web interface for direct control over the local network. [Arkandas] also made good use of the FauxmoESP library to enable the device to be controlled via Amazon Alexa, which fit nicely into their existing smarthome setup. Files are on Github for the curious.

The final build works well, creating a soft light in the habitable area of the bed that can also be readily controlled via voice commands or via web. We’ve seen the ESP32 do other great feats in this arena before, too, albeit of the more colorful variety. Meanwhile, if you’re cooking up your own smart lighting solutions, don’t hesitate to tell the tipsline!

Hexagonal Lighting Brings A Touch Of Elegance To The Workshop

July 31, 2025 by Adam Zeloof 5 Comments

Sometimes, we’re faced with what should be simple household tasks that we choose to make more difficult. Sure, you could buy a clock, hang it on your wall, and move on with your day, or could spend a week or two building the perfect one. [Nejc Koncan] was in one such situation recently when he needed some new overhead lighting. He wanted hexagonal lights — and since none of the off-the-shelf solutions met his exacting requirements, he built his own.

Unlike most of the cycling RGB hexagonal lighting solutions available on the market, [Nejc] wanted elegant white outlines that he could control via HomeAssistant. After some careful design and quite a bit of trial-and-error, he ended up with a highly modular and very professional-looking installation. The hexagons are constructed from LED strips set into aluminum extrusions, with junction PCBs at each intersection. To complete the look, all of the strips and wiring are hidden by diffusers that slot into the extrusions — and of course, the whole thing is open source.

We see lots of lighting projects here at Hackaday, and even other hexagonal lights — but this might just be one of the most refined. Sometimes it’s worth the extra effort to build a totally over-engineered custom solution.

Experience Other Planets With The Gravity Simulator

July 27, 2025 by Bryan Cockfield 8 Comments

As Earthlings, most of us don’t spend a lot of extra time thinking about the gravity on our home planet. Instead, we go about our days only occasionally dropping things or tripping over furniture but largely attending to other matters of more consequence. When humans visit other worlds, though, there’s a lot more consideration of the gravity and its effects on how humans live and many different ways of training for going to places like the Moon or Mars. This gravity simulator, for example, lets anyone experience what it would be like to balance an object anywhere with different gravity from Earth’s.

The simulator itself largely consists of a row of about 60 NeoPixels, spread out in a line along a length of lightweight PVC pipe. They’re controlled by an Arduino Nano which has a built-in inertial measurement unit, allowing it to sense the angle the pipe is being held at as well as making determinations about its movement. A set of LEDs on the NeoPixel strip is illuminated, which simulates a ball being balanced on this pipe, and motion one way or the other will allow the ball to travel back and forth along its length. With the Earth gravity setting this is fairly intuitive but when the gravity simulation is turned up for heavier planets or turned down for lighter ones the experience changes dramatically. Most of the video explains the math behind determining the effects of a rolling ball in each of these environments, which is worth taking a look at on its own.

While the device obviously can’t change the mass or the force of gravity by pressing a button, it’s a unique way to experience and feel what a small part of existence on another world might be like. With enough budget available there are certainly other ways of providing training for other amounts of gravity like parabolic flights or buoyancy tanks, although one of the other more affordable ways of doing this for laypeople is this low-gravity acrobatic device.

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Diffuse glow of red, green, and blue LEDs embedded in silicone

Embedded LEDs For Soft Robots Made From Silicone

July 23, 2025 by John Elliot V 3 Comments

Over on their YouTube channel [Science Buddies] shows us how to embed LEDs in soft robots. Soft robots can be made entirely or partially from silicone. In the video you see an example of a claw-like gripper made entirely from silicone. You can also use silicone to make “skin”. The skin can stretch, and the degree of stretch can be measured by means of an embedded sensor made from stretchy conductive fabric.

As silicone is translucent if you embed LEDs within it when illuminated they will emit diffuse light. Stranded wire is best for flexibility and the video demonstrates how to loop the wires back and forth into a spring-like shape for expansion and contraction along the axis which will stretch. Or you can wire in the LEDs without bending the wires if you run them along an axis which won’t stretch.

The video shows how to make silicone skin by layering two-part mixture into a mold. A base layer of silicone is followed by a strip of conductive fabric and the LED with its wires. Then another layer of silicone is applied to completely cover and seal the fabric and LED in place. Tape is used to hold the fabric and LED in place while the final layer of silicone is applied.

When the LEDs are embedded in silicone there will be reduced airflow to facilitate cooling so be sure to use a large series resistor to limit the current through the LED as much as possible to prevent overheating. A 1K series resistor would be a good value to try first. If you need the LED to be brighter you will need to decrease the resistance, but make sure you’re not generating too much heat when you do so.

If you’re interested in stretchy circuits you might also like to read about flexible circuits built on polyimide film.

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Researching Glow-Powder Left A Few Scars

July 20, 2025 by Brian McEvoy 34 Comments

Content warning: Human alteration and scalpels.
General warning: We are not speaking as doctors. Or lawyers.

If you watch sci-fi, you probably do not have to think hard to conjure a scene in a trendy bar where the patrons have glowing make-up or tattoos. That bit of futuristic flair was possible years ago with UV-reactive tattoo ink, but it has the unfortunate tendency to permanently fade faster than traditional ink. [Miana], a biohacker, wanted something that could last forever and glow on its own. After months of research and testing, she presents a technique with a silica-coated powder and scarification. Reddit post with graphic content.

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DIY Book Lamp Is A Different Take On The Illuminated Manuscript

July 1, 2025 by Navarre Bartz No comments

People have been coming up with clever ways to bring light to the darkness since we lived in caves, so it’s no surprise we still love finding interesting ways to illuminate our world. [Michael] designed a simple, but beautiful, book lamp that’s easy to assemble yourself.

This build really outshines its origins as an assembly of conductive tape, paper, resistors, LEDs, button cells, and a binder clip. With a printable template for the circuit, this project seems perfect for a makerspace workshop or school science project kids could take home with them. [Michael] walks us through assembling the project in a quick video and even has additional information available for working with conductive tape which makes it super approachable for the beginner.

The slider switch is particularly interesting as it allows you to only turn on the light when the book is open using just conductive tape and paper. We can think of a few other ways you could control this, but they quickly start increasing the part count which makes this particularly elegant. By changing the paper used for the shade or the cover material for the book, you can put a fun spin on the project to match any aesthetic.

If you want to build something a little more complex to light your world, how about a 3D printed Shoji lamp, a color-accurate therapy lamp, or a lamp that can tell you to get back to work.

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A Close Look At The Mitxela Precision Clock Mk IV

June 8, 2025 by John Elliot V 15 Comments

Over on his secondary YouTube channel, [Jeff Geerling] recently demoed the new Mitxela Precision Clock Mk IV.

This clock uses GPS to get the current time, but also your location so it can figure out what time zone you’re in and which daylight savings time might apply. On the back a blinking diode announces the arrival of each second. A temperature-compensated crystal oscillator (TCXO) is employed for accurate time-keeping.

The clock can be folded in half, thereby doubling as a clapperboard for movie makers. The dimming system is analog, not pulse width modulation (PWM), which means no visible flashing artifacts when recording. It is highly configurable and has USB connectivity. And it has not one but two ARM microcontrollers, an ARM STM32L476, and an ARM STM32L010. If you’re interested, you can pick one up for yourself from [Mitxela]’s shop.

Toward the end of his video [Jeff] does some navel gazing, thinking about what might be required if future versions of the clock wanted to get down into precision at the nanosecond level. Do you arrange it so the light arrives at the viewer’s eyeball at the right time? Or do you update it on the clock at the right time and let the viewer know about it after a minuscule delay? Philosophical preponderances for another day!

We should add that we’ve seen plenty of cool stuff from [Mitxela] before, including the Euroknob and these soldering tweezers.

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