An Automated Water Tank Controller

August 2, 2026 by Zoe Skyforest 12 Comments

[Jumpor] lives in a part of India where the water infrastructure is a little frustrating to use. Water gets delivered to underground tanks outside of homes, and must then be regularly pumped into rooftop tanks prior to use inside the building. Typically, this pumping is handled manually—by switching on a pump and running it until water comes out of an overflow pipe to indicate the rooftop tank is full. [Jumpor] decided to improve this wasteful and time consuming process with a little automation project.

The build is based around an ESP32 microcontroller. It’s hooked up to an ultrasonic sensor which can measure the water level inside the rooftop water tank. When the sensor detects the level descending below a set point, the microcontroller fires a relay to trigger the lift pump to fill up the tank. Once the sensor detects the tank is full, the pump is shut off, saving liters of water compared to waiting for water to pour out of the overflow as an indicator of the same.

It’s a simple enough project, but [Jumpor] was sure to include the important practical considerations. Since the rig was being installed in a rental, it was desirable to not make any permanent modifications to the water system. Thus, a fresh cap for the water tank was modified to host the electronics and level sensor, such that the original could be replaced at a later date. Due consideration was also paid to things like avoiding crossing the minimum detection threshold of the sensor, which could lead to accidental overflows if not managed correctly.

The aim of this project was to ease the day to day burden of maintaining a basic utility. That’s the sort of project we love to see around these parts.

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A Complex Way To Push A Button

July 31, 2026 by Bryan Cockfield 17 Comments

We’ve likely all looked at a simple problem in our lives and thought that it would be an easy fix, only to realize that the project is enormously more complicated than we first realized. Whether that’s starting a home improvement project, doing a quick repair to a bicycle or car, or trying to install an obscure piece of software on a Linux machine, the amount of time we budget for these tasks often ends up woefully underestimated. [Oscar]’s night light needs to have its brightness set every night, and it seems easy enough to get a microcontroller to automate that, right?

Well, upon opening the small device, the first issue is that there is no labeling on any of the parts, so simply adding a jumper on to existing microcontroller pins without damaging anything wouldn’t easily be possible. Adding a secondary microcontroller is the next logical step, but the power supply in the night light is extremely underpowered so using even the smallest Raspberry Pi or off-the-shelf Arduino was out of the question too. [Oscar] instead chose an ATtiny85, which solves the power requirement issue, but these are a bit more of a challenge to program without a USB device. From there, it needs a transistor wired in to the circuit to actually push the button for him, plus a few support resistors, so [Oscar] actually had a PCB custom-built to hold all of these components.

Even after all of that, the space within the night light enclosure made installing the PCB a challenge, but in the end he has a device which, when his home automation system powers on the plug for the nightlight, automatically boots up and pushes the switch the required number of times and then puts itself to sleep. We’d call that a success even after the colossal effort getting this inexpensive, small light working the way he wanted. There are some other low-powered solutions for problems like these too, as long as being battery-powered isn’t a dealbreaker.

Samsung’s SmartThings API Terminates Free Access

July 28, 2026 by Maya Posch 26 Comments

If there’s one constant in the world of commercial home automation solutions, it is that of decreasing availability and higher costs as time goes on. So too with Samsung’s SmartThings, the API of which will cease free access in October of 2026.

While this does not affect people who use the SmartThings app, any system that relies on access to this API will soon face a $4.99 per month fee for non-commercial users, with various commercial tiers also in the pipeline. While the rest of the blog post has all the elegance of the output of a ‘please generate a list of plausible excuses’ query to ChatGPT, the most likely reason is that offering free services after the sale of an Internet of Things device will never be profitable.

SmartThings was originally a 2012 Kickstarter campaign that ended up becoming successful enough that the company was bought by Samsung in 2014. Its current offerings are very much like other Smart Home products, with recently added support for Matter and interoperability with third-party devices.

If you have SmartThings integrated with your Home Assistant installation, you are also likely affected by this change if at any point you use the API. Of course, this isn’t the first time that SmartThings customers had to scramble to fix broken infrastructure, such as when in 2021 the original hubs got discontinued.

A vaguely perforated metal cylinder sits on a wooden box with a grey cylinder and LCD display atop it. There are holes in the top of the grey cylinder for air to flow through.

A Smarter DIY Air Filter

July 21, 2026 by Navarre Bartz 25 Comments

As predominantly indoor creatures, it’s important to maintain a healthy habitat for the hacker. [Kishan Pratap Singh] designed a clever solution in AirSense, an ESP32-powered air filter.

If you’re thinking of cleaning the air in your environment, you might also want to know some properties about the air coming out of the filter. AirSense measures PM2.5 dust concentration, Air Quality Index (AQI), temperature, humidity, and atmospheric pressure. The various sensors are mounted along the exhaust path of the filter, which lets your know what kind of air it’s pumping out.

The system drives a 150 mm exhaust fan mounted in a 3D printed cap that pulls air through a cylindrical Xiaomi HEPA filter inside a perforated metal trash can enclosure. The ESP32 and an LCD readout of the environmental data also live in the cap, giving the device a sleek look. While [Singh] chose to run the filter continuously, we wonder if it might be interesting to set it up to only filter the air if air quality drops below a certain level to conserve power, especially if you’re on a time-of-use power plan. That would require redesigning the sensor assembly (or running the unit in reverse), so maybe it’s over-complicating things?

We’ve seen the Xiaomi Air purifier filter mentioned before, but under the auspices of hacking it’s filter DRM, an open source air filter designed by [Naomi Wu], and even an ESP32 pressed into service to plug an air purifier into Home Assistant.

IBM Home Director: Home Automation In 1996

July 8, 2026 by Maya Posch 20 Comments

Back in the 1990s IBM had a pretty sizeable presence in the PC market, including its rather spiffy Aptiva series of PCs. Naturally their PCs had to feature heavily in another consumer-related thing that was popular in the 1990s, being smart home automation in the form of IBM Home Director. Recently [Ionic1k] took a look at this blast from the past, starting with one of the original IBM commercials.

At its core it used the same X10 protocol that similar solutions from RadioShack and others used, with many modules and packages you could get to use with it. You could also get a more bespoke installation performed at your home to move beyond mere X10, which some people are still finding when they’re buying a house.

Since this uses powerline communication, it required no wires to be run, just the requisite modules to be plugged into a power outlet, with the video demonstrating the basic setup and installation. The PC itself is plugged into the control module via the serial port, from which the Home Director control software can be used to create a configuration and control the state of connected modules.

Although X10 has the same issues as any kind of powerline communication, overall it seems like a very nice system, with a wide range of modules and absolutely easy to set up even for a casual Windows user.

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A device with a brown plastic gear cylinder and indicator on the left and a series of black pieces approximately the size of tongue depressors sits on a butcher block workbench. A thin brown divider with the word "Finished" sits between sets of the presumably chalkboard tongue depressors.

A New Twist On The To Do List

July 3, 2026 by Navarre Bartz 11 Comments

Humans are odd creatures, and no two are exactly alike, which is likely why so many different methods exist for tracking the progress of tasks that must be accomplished. [Simone Giertz] has graced us with her own spin on task tracking that adds an element of chance.

[Giertz] tells us that she started with written lists that she tackled in dice-determined order to keep her from overthinking or cherry-picking tasks. While this worked fine, she longed for a more elegant solution. Approaching the UI first, unlike any Open Source project ever, she determined that a marker that could randomly point to a task on a vertical list would be most pleasant.

The bulk of the project was evaluating different mechanisms to make the marker pick tasks at random while not selecting a task that had already been completed. A set of magnetic toggles that could repel the marker proved ineffective, but a simpler solution involving moving the completed tasks past a divider won the day. The finished product has a satisfying selection mechanism that makes interacting with the chore chart a joy, which probably helps make it more likely things get done.

We’ve seen many productivity hacks over the years, including Arya’s Hacking the Self, this rotary time tracker, or this e-ink macropad.

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Hacking A Reverse Osmosis Water Filter Through Its Smart Faucet

June 30, 2026 by Maya Posch 27 Comments

Reverse-osmosis (RO) systems are one way to ensure that you get very clean drinking water. The Waterdrop G3P600 variety that [Tomasz Wasilczyk] recently purchased is definitely among the fanciest and ‘smartest’, with the faucet having its own 7-segment display and gaggle of LEDs connected to the actual RO unit with a four-pin connector. This naturally meant that whatever protocol runs on this cable had to be reverse-engineered for science.

Now with more custom PCB. (Credit: Tomasz Wasilczyk) — Now with more custom PCB.

The main practical benefit here is to make the system smarter — such as plugging it into a home automation system with ESPHome support, as well as make it play nice with refrigerator lines.

What automation and monitoring options exist here thus depend on what data gets sent between the RO unit and the faucet. Fortunately this turned out to be quite extensive, ranging from filter health, the water quality and pump status as well as air temperature and faucet state.

Unsurprisingly the four-pin connector turned out to be a basic serial link, with 5 V, ground and a 9,600 baud connection. From this it was easy enough to deduce the protocol, and by looking at what lit up on the faucet, a custom PCB wasn’t far behind.

After one blown-up fuse later due to getting 24 V instead of 12 V on the RO unit when tapping off power, the unit popped to life and was able to be connected to Home Assistant, from where the entire functionality and what triggered what could be mapped out. Of course, there’s still more to be discovered and reverse-engineered in the unit, but this seems like a good place to start.