2025 One Hertz Challenge: Abstract Aircraft Sculpture Based On Lighting Regulations

August 12, 2025 by Lewin Day 9 Comments

The 2025 One Hertz Challenge is really heating up with all kinds of projects that do something once every second. [The Baiko] has given us a rather abstract entry that looks like a plane…if you squint at it under the right conditions.

It’s actually quite an amusing abstract build. If you’ve ever seen planes flying in the night sky, you’ve probably noticed they all have similar lights. Navigation lights, or position lights as they are known, consist of a red light on the left side and a green light on the right side. [The Baiko] assembled two such LEDs on a small sliver of glass along with an ATtiny85 microcontroller.

Powered by a coin cell, they effectively create a abstract representation of a plane in the night sky, paired with a flashing strobe that meets the requirements of the contest. [The Baiko] isn’t exactly sure of the total power draw, but notes it must be low given the circuit has run for weeks on a 30 mAh coin cell.

It’s an amusing piece of PCB art, though from at least one angle, it does appear the red LED might be on the wrong side to meet FAA regulations. Speculate on that in the comments.

In any case, we’ve had a few flashers submitted to the competition thus far, and you’ve got until August 19 to get your own entry in!

2025 One Hertz Challenge: Blinking An LED The Very Old Fashioned Way

August 5, 2025 by Jenny List 10 Comments

Making an LED blink is usually achieved by interrupting its power supply, This can be achieved through any number of oscillator circuits, or even by means of a mechanical system and a switch. For the 2025 One Hertz Challenge though, [jeremy.geppert] has eschewed such means. Instead his LED is always on, and is made to flash by interrupting its light beam with a gap once a second.

This mechanical solution is achieved via a disk with a hole in it, rotating once a second. This is driven from a gear mounted on a 4.8 RPM geared synchronous motor, and the hack lies in getting those gears right. They’re laser cut from ply, from an SVG generated using an online gear designer. The large gear sits on the motor and the small gear on the back of the disk, which is mounted on a bearing. When powered up it spins at 60 RPM, and the LED flashes thus once a second.

We like this entry for its lateral thinking simplicity. The awesome 2025 One Hertz Challenge is still ongoing, so there is still plenty of time for you to join the fun!

Continue reading “2025 One Hertz Challenge: Blinking An LED The Very Old Fashioned Way” →

Fire Alarm Disco Party

August 4, 2025 by Ian Bos 34 Comments

What should your first instinct be when the room catches on fire? Maybe get out of the room, pull an alarm, and have a disco party? Not your first instinct? Well, this seemed pretty obvious to [Flying-Toast], who retrofitted an old fire alarm to activate a personal disco party.

After finding a fire alarm being sold on eBay, [Flying-Toast] couldn’t resist the urge to purchase one to use for his own purposes. He immediately gutted the life-saving internals to fill the shell with his own concoction of ESP goodness to be activated by the usual fire alarm mechanism. This sends a signal to the next elements of the party system.

Every part of the party system receives this activation signal, including the most important part, the party lights. Using a generic crystal disco ball and its own ESP, the party lights are more than sufficient to create the proper panic party. Of course, what is a party without music? With another ESP board and salvaged speakers, the proper atmosphere can be set right before the venue burns to the ground. The final touch is the additional hacked WIFI relays to turn off the lights in the room.

Priorities are important in emergencies, and that is exactly what [Flying-Toast] gave us with this project. Learning from this expertise is important, but how about learning from the near misses? For some risky decision making, be sure to check out the near nuclear war that was almost caused by a false alarm!

Continue reading “Fire Alarm Disco Party” →

Raspberry Pi Pico LED display sitting in window sill

An Ode To The Aesthetic Of Light In 1024 Pixels

August 2, 2025 by Heidi Ulrich 3 Comments

Sometimes, brilliant perspectives need a bit of an introduction first, and this is clearly one. This video essay by [Cleggy] delivers what it promises: an ode to the aesthetic of light. But he goes further, materializing his way of viewing things into a beautiful physical build — and the full explanation of how to do it at home.

What’s outstanding here is not just the visual result, but the path to it. We’ve covered tons of different LED matrices, and while they’re all functional, their eventual purpose is left up to the builder, like coasters or earknobs. [Cleggy] provides both. He captured a vision in the streets and then built an LED matrix from scratch.

The matrix consists of 1024 hand-soldered diodes. They’re driven by a Raspberry Pi Pico and a symphony of square waves. It’s not exactly a WS2812 plug-and-play job. It’s engineered from the silicon up, with D-latches and demultiplexers orchestrating a mesmerizing grayscale visual.

Pulse-width modulation (PWM) is the secret ingredient of this hack. [Cleggy] dims each white pixel separately, by varying the duty cycle of its light signal. The grayscale video data, compressed into CSV files, is parsed line-by-line by the Pico, translating intensity values into shimmering time slices.

It transforms the way you see and perceive things. All that, with a 1000 LED monochrome display. Light shows are all highly personal, and each one is a little different. Some of them are really kid stuff.

Continue reading “An Ode To The Aesthetic Of Light In 1024 Pixels” →

Custom Bedroom Lighting Controlled By Alexa

August 2, 2025 by Lewin Day 3 Comments

[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.

Continue reading “Experience Other Planets With The Gravity Simulator” →