A DIY DIN rail mounted rack of PLC components for home automation

2024 Home Sweet Home Automation: A DIY SCADA Smart Home

March 20, 2024 by Dave Rowntree 22 Comments

A SCADA-style display of icons and control buttons — Touch-screen control and monitoring

Supervisory control and data acquisition, or SCADA, systems sit in the background in industrial settings, performing all kinds of important jobs but in an ad-hoc setup, depending on the precise requirements of the installation. When we think about home automation systems, they’re pretty much the same deal: ad-hoc systems put together from off-the-shelf components and a few custom bits thrown in. [Stefan Schnitzer] clearly has significant knowledge of SCADA in an industrial setting and has carried this over into their home for their entry into the Hackaday 2024 Home Sweet Home Automation Contest. Continue reading “2024 Home Sweet Home Automation: A DIY SCADA Smart Home” →

IoT Air Purifier Makes A Great Case Study In Reverse Engineering

February 6, 2024 by Dan Maloney 10 Comments

Here at Hackaday, about the only thing we like more than writing up tales of reverse engineering heroics is writing up tales of reverse engineering heroics that succeed in jailbreaking expensive widgets from their needless IoT dependency. It’s got a real “stick it to the man” vibe that’s hard to resist.

The thing is, we rarely see a reverse engineering write-up as thorough as the one [James Warner] did while integrating an IoT air purifier into Home Assistant, so we just had to make sure we called this one out. Buckle up; it’s a long, detailed post that really gets down into the weeds, but not unnecessarily so. [James] doesn’t cloud-shame the appliance manufacturer, so we can’t be sure who built this, but it’s someone who thought it’d be a swell idea to make the thing completely dependent on their servers for remote control via smartphone. The reverse engineering effort started with a quick look at the phone app, but when that didn’t pay off in any useful way, [James] started snooping on what the device was talking about using Wireshark.

One thing led to another, wires were soldered to the serial pins on the ESP32 on the purifier’s main board, and with the help of a FlipperZero as a UART bridge, the firmware was soon in hand. This gave [James] clues about the filesystem, which led to a whole Ghidra side quest into learning how to flash the firmware. [James] then dug into the meat of the problem: figuring out the packet structure used to talk to the server, and getting the private key used to encrypt the packets. This allowed a classic man-in-the-middle attack to figure out the contents of each packet and eventually, an MQTT bridge to let Home Assistant control the purifier.

If it sounds like we glossed over a lot, we know — this article is like a master class on reverse engineering. [James] pulled a lot of tools out of his kit for this, and the write-up is clear and concise. You may not have the same mystery fan to work with, but this would be a great place to start reverse engineering just about anything.

Thanks to [ThoriumBR] for the tip.

FLOSS Weekly Episode 767: Owntracks, Are We There Yet?

January 24, 2024 by Jonathan Bennett 2 Comments

This week Jonathan Bennett and Jeff Massie talk with JP Mens about Owntracks, the collection of programs that lets you take back control of your own location data. It’s built around the simple idea of taking position data from a mobile phone or other data source, sending it over MQTT to a central server, and logging that data to a simple data store.

From there, you can share it as trips, mark points of interest, play back your movement in a web browser, and more. And because it’s just JSON inside MQTT, it’s pretty trivial to make a connector to interface with other projects, like Home Assistant. We’ve even covered the process!

Continue reading “FLOSS Weekly Episode 767: Owntracks, Are We There Yet?” →

Toy Gaming Controller Makes The Big Leagues

November 1, 2023 by Bryan Cockfield 5 Comments

Some of the off-brand video game consoles and even accessories for the major brands can leave a lot to be desired. Whether it’s poor build quality or a general lack of support or updates, there are quite a few things on the market not worth anyone’s time or money. [Jonathan] was recently handed just such a peripheral, a toy game controller originally meant for a small child, but upon further inspection it turned into a surprisingly hackable platform, capable of plenty of IoT-type tasks.

The controller itself was easily disassembled, and the functional buttons within were wired to a Wemos D1 Mini instead of the originally-planned ESP32 because of some wiring irregularities and the fact that the Wemos D1 Mini having the required amount of I/O. It’s still small enough to be sealed back inside the controller as well, powered by the batteries that would have powered the original controller.

For the software, [Jonathan] is using MQTT to register button presses with everything easily accessible over Wi-Fi, also making it possible to update the software wirelessly. He was able to use it to do a few things as proof-of-concept, including playing a game in PyGame and controlling a Sonos speaker, but for now he’s using it to control an LED sculpture. With something this easily modified, though, it would be pretty straightforward to use it instead for a home automation remote control, especially since it is already set up to use MQTT.

Continue reading “Toy Gaming Controller Makes The Big Leagues” →

Keeping Badgers At Bay With Tensorflow

October 15, 2023 by Danie Conradie 9 Comments

Human-animal conflict is always a contentious issue, and finding ways to prevent damage without causing harm to the animals often requires creative solutions. [James Milward] needed a humane method to stop badgers and foxes from uprooting his garden, leading him to create the Furbinator 3000, a system that combines computer vision with audio deterrents..

[James] initially tried using scent repellents (which were ignored) and blocking access to his garden (resulting in more digging), but found some success with commercial ultrasonic audio repellent devices. However, these had to be manually turned off during the day to avoid annoying activation of the PIR motion sensors by [James] and his family, and the integrated solar panels couldn’t keep up with the load.

This presented a good opportunity to try his hand at practical machine vision. He already had a substantial number of sample images from the Ring cameras in his garden, which he turned into a functional TensorFlow Lite model with about 2.5 hours of training. He linked it with event-activated RTSP streams from his Ring cameras using the ring-mqtt library. To minimize false positives on stationary objects, he incorporated a motion filter into the processing pipeline. When it identifies a fox or badger with reasonable accuracy, it generates an MQTT event.

[James] modified the ultrasonic devices so they would react to these events using an ESP8266-based WeMos D1 Mini Pro development board and added an external 5 V power supply for sustained operation. All development was performed in a Docker container which simplified deployment on a Raspberry Pi 4.

After implementing the system, [James] woke up to the satisfying sight of his garden remaining untouched overnight, a victory that even earned him some coverage by the BBC.

Thanks for the tip [Laurent]!

A hot tub with a smartphone in front showing real-time sensor data

ESP32 Keeps Track Of Hot Tub’s Vital Signs

October 1, 2023 by Robin Kearey 11 Comments

Like swimming pools, hot tubs need regular monitoring to ensure their water stays clean and clear. An average person might take a water quality reading once or twice a week using test strips, but such a low sampling rate obviously won’t do for a hacker. [Stephen Carey] has therefore built a hot tub monitor that checks the water quality every minute and reports it on a neat mobile dashboard.

[Stephen]’s system uses commercially available sensors that track pH levels and Oxidation-Reduction Potential (ORP), both basic measurements that indicate water quality. A second set of sensors keeps track of the temperature of the water and the outside air, which should help in finding insulation failures and keeping energy use under control.

An ESP32 reads the sensors and sends out the data through WiFi. [Stephen] programmed the ESP32 in MicroPython, using an MQTT driver to connect it to Home Assistant. By looking at the graphs generated, you can tell when someone entered the tub from a step change in pH and ORP. It’s even possible to generate alerts when any of the values drift outside their acceptable range – we can already imagine an alarm going off when someone enters without having showered first.

The system also has a calibration mode to check the sensors against a well-defined buffer solution. As with many chemical sensors, the pH and ORP probes gradually lose their active material and need to be replaced after about a year. Good ones aren’t cheap, but [Stephen] has found pretty decent low-cost alternatives on AliExpress that should be fine for a home setup.

If you also want your tub or pool to be actively managed, you’ll need a more complex system, perhaps even one that can also dispense chemicals. If your hot tub is heated by a wood fire, however, all you need is a way to alert the person tending the fire.

Streaming Video From An ESP32

September 5, 2023 by Bryan Cockfield 11 Comments

The ESP32, while first thought to be little more than a way of adding wireless capabilities to other microcontrollers, has quickly replaced many of them with its ability to be programmed as its own platform rather than simply an accessory. This also paved the way for accessories of its own, such as various sensors and even a camera. This guide goes over taking the input from the camera and streaming it out over the network to multiple browsers.

On the server side of things, the ESP32 and its attached camera are set up with MQTT, a lightweight communications protocol which uses a publish/subscribe model to send information. The ESP32 is configured to publish its images only, but not subscribe to any other nodes. On the client side, the browser runs a JavaScript program which is able to gather these images and stitch them together into a video.

This can be quite a bit of data to send out over the ESP32’s compact hardware, so there are some tips and tricks for getting more out of these little devices, including using an external antenna for better Wi-Fi signal, or omitting it entirely in favor of Ethernet. As far as getting a lot out of a tiny microcontroller, though, leveraging MQTT really helps the ESP32 go a long way. These chips have come along way since they were first introduced; they’re powerful enough to act as 8-bit gaming consoles too.

Thanks to [Surfskidude] for the tip!