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.

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.

Sold by German DIY store OBI, the OBI Energy Tracker is a €15 set of two devices, one of which you essentially stick on top of your existing electricity meter. This then allows for electricity usage to be measured and tracked, with the data sent to the second, gateway device. This latter cloud-bound device is linked to an OBI account via the heyOBI app. This correspondingly called for the gateway device to be reverse-engineered and freed from its cloud-based shackles, a task that [Aaron Christophel] happily took upon himself.

The whole process is also covered in two videos, with the first providing all the essentials on reprovisioning the original firmware for a local MQTT server in English, while the second, German-language video focuses on custom firmware for the ESP32-C3 inside of the gateway device.

Inside the reader device is a Cortex-M0+-based BAT32G135 MCU that communicates with the meter via its IR protocol. This is then communicated via 868 MHz LoRa to the gateway device that will be placed somewhere within Wi-Fi reach by the user. Inside this latter device is as mentioned the ESP32-C3, which by default runs firmware that communicates via secure MQTT with an AWS cloud instance for the typical cloud-based shenanigans.

The aforementioned reprovisioning option doesn’t require firmware flashing, just a handful of steps to follow. This involves fetching the 32-bit TEA key, generating your own PKI, running your own MQTTS-capable broker and having the provided Python script handle the rest from there.

Flashing custom firmware is the other option, with straightforward UART/JTAG reflashing sadly disabled by the manufacturer. With the effort required here you could perhaps argue that simply connecting the reader device to a custom gateway device might be a lot easier, especially if you already have a LoRa transceiver and associated hardware.