A Lightweight Smart Home Server

June 6, 2023 by 31 Comments

Working towards automating a few things in a home often seems simple on the surface, but it’s easy for these projects to snowball into dozens of sensors and various servos, switches, and cameras strewn about one’s living space. The same sort of feature creep sneaks into some of the more popular self-hosted home server platforms as well, with things like openHAB requiring so much computing power that they barely function on something like a Raspberry Pi. [Paulo] thought there should be a more lightweight way of tackling a project like this, and set about building his own smart home server with help from some interesting software.

The project is based around the Dirigera hub from Ikea, partially because [Paulo] is planning to use other smart home devices from Ikea as he can easily find them where he is, and also because these devices tend to use Zigbee, a non-proprietary communications standard. This means that if he ever wants to swap out the hub for another one in the future, it won’t be difficult to do. From here the major hurdle is that using the default software from these devices is fairly limiting, so [Paulo] reached for a Raspbee 2 Zigbee gateway for use with a Raspberry Pi and an extremely lightweight and customizable web server called Mako to make this happen. Using Lua as the high-level language to tie everything together he was able to easily deploy the server to control the Ikea hub and devices and automate them in any way he sees fit.

While it is true that software like openHAB and others already exists to do virtually any home automation task that could be imagined, if you’re looking to do something with a bare minimum of computing power something like [Paulo]’s solution is likely going to be the fastest and most reliable method of getting a few things automated around the home. If you’re looking for something completely open source and built from the ground up, though, we have seen a few alternative smart home solutions like this one which don’t rely on any proprietary hardware or software, but do take a little bit more effort on the user’s part.

Building A Giant Vacuum Tube Smart Lamp

May 19, 2023 by 12 Comments

Vacuum tubes are pretty, which is why they’re often showcased externally on exquisitely-expensive home Hi-Fi hardware. But if you just want to gaze at their beauty without making any noise, why not build this vacuum tube lamp from [Noel Törjék] instead?

[Noel] got into some creative reuse with this build, with the main body consisting of a bell jar and wooden bowls. The internal structure is then created from jar lids, wire, metal sheeting, steel rods, and galvanized wire mesh. Simple modelling techniques are used to assemble the internal parts of the “valve,” including the grid and the electrodes and so on. As for light, [Noel] employed a ZigBee LED driver that he could control over his smart home setup via a Philips Hue bridge.

The final result looks like an extra-large tube. Anyone who knows what it is will spot that it’s not a real one, but they’re also exactly the audience that will appreciate it for what it is. Everyone else will probably just think you’ve taken an interest in strange art-deco replica lighthouses. It’s not the first time we’ve seen replica valves around these parts, though, and we’re sure it won’t be the last!

Taking Apart IKEA’s Latest Air Quality Sensor

March 16, 2023 by 30 Comments

Whether it’s because they’re concerned about worsening pollution or the now endemic variants of COVID-19, a whole lot of people have found themselves in the market for a home air quality monitor thee last couple of years. IKEA noted this trend awhile back, and released the VINDRIKTNING sensor to capitalize on the trend.

The device must have sold pretty well, because last month the Swedish flat-packer unveiled the considerably more capable (and more expensive) VINDSTYRKA. Now thanks to the efforts of [Oleksii Kutuzov] we’ve got a fantastic teardown of the new gadget, and some more information on the improvements IKEA made over its predecessor.

Certainly the most obvious upgrade is the addition of an LCD readout that displays temperature, humidity, and how many particulates the device detected in the air. There’s even a “traffic light” colored indicator to show at a glance how bad your air supply is. The other big change is the addition of wireless, though unlike the WiFi hacks we saw for the VINDRIKTNING, this built-in capability uses Zigbee and is designed to plug into IKEA’s own home automation ecosystem.

Speaking of those hacks, a GitHub user by the name of [MaartenL] chimes in to say they’ve managed to hook an ESP32 up to test pads on the VINDSTYRKA motherboard, allowing the parasitic microcontroller to read the device’s sensors and report their data on the network over a service like MQTT, without impacting the sensor’s normal operations. This is how the first hacks on the older VINDRIKTNING were pulled off, so sounds like a promising start.

But even if you aren’t looking to modify the device from its original configuration (how did you find this website?), it seems pretty clear the VINDSTYRKA is a well-built piece of kit that will serve you and your family well. Which is more than what could be said for some of the cheapo environmental sensors flooding the market.

Thanks to [killergeek] for the tip.

E-Paper Wall Paper

March 15, 2023 by 7 Comments

Just like the clock clock of old, there’s something magical about a giant wall of smaller pieces working together to make a larger version of that thing. The E-Paper Wall 2.0 by [Aaron Christophel] is no exception as it has now upgraded from 2.9″ to 7.4″ screens.

On the 1.0 version, the bezels made it harder to make out the image. The larger screens still have bezels but the larger screen area makes it much easier to make out the image. 3D-printed clips hold the displays onto a plywood backer. We can marvel that e-ink price tags brought the price of e-ink down so that building a wall is still expensive but not eye-wateringly so. The 5×9 array likely uses a module sold on DigiKey for $47 each.

So aside from being willing to drop some money on a custom piece of art, what’s special about this? The real magic comes with the firmware and tooling that [Aaron] developed to flash custom firmware onto each of the 45 displays. A 100MHz ZBS243/SEM9110 8051-based controller lives inside each display and [Aaron] even has a Ghidra plugin to reverse-engineer the existing firmware. It only has 64kb of flash onboard, so [Aaron] devised a clever compression technique that enabled him to store complex images on the displays. A 3D-printed jig with pogo pins means flashing them doesn’t require soldering pins or headers, just drop it on and flash it with an Arduino with a helpful library [Aaron] wrote. A central station communicates with the various displays over ZigBee to send image updates.

The 8051 has a funny way of showing up in projects like this portable soldering iron or the TV Guardian. In many ways, it is a boon for us hackers as it makes it easier to reverse engineer and write new custom firmware when so many devices use the same architecture.

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Connecting Commercial 433 MHz Sensors To MQTT And Home Assistant With RTL-SDR

December 26, 2022 by 37 Comments

When [Elixir of Progress] was looking at setting up environmental sensors around their home to keep track of temperature, humidity and such, the obvious ideas of using WiFi-connected sensors didn’t work due to lack of WiFi range. Although Zigbee (Z-wave) sensors have longer range than WiFi, they are decidedly more expensive, proprietary and require a special transceiver hub. That’s where 433 MHz sensors for weather stations come into the picture.

The idea is simple: virtually all of those sensors – many of them rated for outdoor use – use the unlicensed 433 MHz spectrum that can easily be captured using cheap RTL-SDR (software defined radio) USB dongles. With the data stream from these sensors captured, the open source rtl_433 project enables automatic decoding of these data streams for a wide range of supported sensors.

While Realtek RTL2832-based and other RTL-SDRs can be found for quite cheap, it should be noted that these can run quite hot. Rather than heatsinking the IC, for this project it was elected to only listen sporadically and allow the RTL-SDR receiver to cool down in between listening sessions.

Getting the data from there into Home Assistant, InfluxDB or similar is easy, as rtl_433 can output the decoded data directly to an Influx database, MQTT broker as well as other formats. In this case, the data was sent via MQTT with the Home Assistant instance configured to treat these MQTT topics as sensors. With each sensor’s location carefully registered, this allows for setting up a dense, very low-power network of 433 MHz sensors for monitoring and home automation purposes.

Circadian Lighting For The Home Via Home Assistant

November 13, 2022 by 10 Comments

Artificial lighting is great, in that it lets us work and live well into the night. However, our bodies are dependent on the natural lighting cycles of the sun as part of their basic operation, and artificial lighting can interfere with this. [Tyler Cipriani] decided to use Home Assistant with some smart lights to try and make home lighting more suitable for our natural circadian rhythms.

The basic intent was to give the home bright white/blueish light during the day, matching the sun’s output. The light would then be altered to warmer yellow/red tones in the evening. The eye has cells that respond to blue light to regulate our circadian rhythms with the presence of the sun, so reducing blue light at night may help reduce disruption to sleep and other body processes.

Home Assistant has a Circadian lighting component available built specifically for this task. It’s a useful smart home tool for achieving such a job, too, as it readily works with a wide variety of hardware from different vendors. In [Tyler]’s case, light switches are Zigbee devices that talk to Home Assistant via a Zigbee2MQTT hookup and a Combee Zigbee gateway. Lights around the home are a mixture of Philips Hue devices and other brands of smart lights.

[Tyler] states the effects are “subtle but noticable.” He notes that it’s easier to feel sharp and work during the day, but harder to continue the lighting warms and dims at night. He points out that this is a design feature to help keep him on a healthy sleep schedule.

We’ve seen other circadian rhythm lights before. In fact, NASA uses them on the ISS, but you can build your own for a lot less than they spent. If you’ve got your own circadian lighting hacks, don’t hesitate to drop us a line!

E-paper Price Tags Combined To Create A Large Wireless Display

August 5, 2022 by 3 Comments

E-paper price tags have become popular for retail stores over the past few years, which is great for hackers since we now have some more cheap commodity hardware to play with. [Aaron Christophel] went all on creating grid displays with E-paper price tags, up to a 20×15 grid.

E-paper price tags are great for these kinds of projects, since they are wireless, lightweight, and can last a long time with the onboard batteries. To mount the individual tags on the plywood backboard,[Aaron] simply glued Velcro to the backboard of the tags. The displays’ firmware is based on the reverse engineering work of [Dmitry Grinberg], flashed to a few hundred tags using a convenient 3D printed pogo pin programming jig. All the displays are controlled via a Zigbee USB dongle plugged into a PC running station software.

[Aaron] is also experimenting with the displays removed from their enclosure and popped into a 3D printed grid frame. The disadvantage is the loss of the battery holders and the antenna, which are both integrated into the enclosure. He plans to get around this by powering the displays from a single large battery, and connecting an ESP32 to the displays via ISP or UART.

This project comes hot on the heels of another E-ink grid display project that uses Bluetooth and a rather clever update scheme.

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