Microwave Motion Detector Notifies Your Smart Phone

February 20, 2025 by Lewin Day 16 Comments

Your garden variety motion detector uses IR, but these days, there are fancier technologies for achieving similar goals. If so desired, you can source yourself a microwave-based presence sensor instead. Indeed, like [N-08 Labs], you might like to whip one up into a basic intrusion detection system.

The idea is simple enough—take a RCWL-0516 microwave presence sensor, and set it up to detect motion and warn you when it happens. It’s a simple part to use—it simply drives a 3.3 volt logic output high if it detects someone or something. It basically just emits a microwave signal and detects a change in phase when someone or something—usually something fleshy—is in front of it. [N-08 Labs] simply hooked one up to an IO pin on an ESP8266, with the microcontroller board set up to communicate wirelessly with a Blynk IoT app, which then in turn fires off a smartphone notification that the sensor picked something up. The whole thing is built inside the shell of an AC adapter that provides power and let it easily hide in plain sight.

A project like this doesn’t just have to be for security purposes. You might even just use it to determine when your pet (or a racoon) is using the cat door, or similar. Indeed, we’ve seen great solutions to that particular problem, too. Video after the break.

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Gimbal Clock Relies On Servos For Its Cool Movements

January 16, 2025 by Lewin Day 1 Comment

In the annals of human history, clocks got boring there for a while. Most were just variations on hands spinning in a circle, with the occasional tweeting bird mechanism to liven things up. These days, we’re treated to all kinds of original and oddball designs, like this neat gimbal clock from [Twisted&Tinned].

The concept of the build is straightforward enough. It has four main vertical arms, each with a servo at the base that rotates about a vertical axis. Upon each arm are between one and three servos which rotate 3D printed structures in the shape of numbers. A Wemos D1 Mini microcontroller commands the servos to the correct positions to display the current time. It also uses its WiFi connection to get accurate time updates directly from a network time server.

It’s quite an artistic build—and it’s rather enjoyable to watch this one flex and twist its way into displaying the right time. It’s also easier to read at a glance than some of the more unintelligible designs out there. Indeed, we see all kinds of neat and innovative clocks around these parts.

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Using The ESP8266 For Low-Cost Fault Injection

January 15, 2025 by Tom Nardi 10 Comments

As a general concept, fault injection is a technique that studies how a system reacts to unusual or unexpected external forces. The idea is that, if you can trigger a glitch at the precise moment, you might be able to use that to your advantage in disabling security features or otherwise gaining further access to the device in question. In the hardware world, this could be achieved by fiddling with the power going into the device, or subjecting it to extreme temperatures.

We’ve covered voltage glitching attacks on these pages in the past, but most of the tools used are fairly expensive if you’re not doing this kind of thing professionally. Luckily for us, [Aditya Patil] has developed a fault injection tool that can run on a standard ESP8266 development board. Obviously it’s not as capable as a bespoke device costing hundreds of dollars, but if you just want to experiment with the concept, it’s a fantastic way to wrap your head around it all.

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A chicken's egg with many holes glows beneath a glass globe set atop an inverted wooden bowl.

Glowing Egg Is A One-Oeuf Solution For Tracking Cycles

September 7, 2024 by Kristina Panos 28 Comments

Look, if something happened to you every three weeks or so to basically turn you into a different person and factored heavily into whether any new humans were created, you’d probably want to keep abreast of the schedule, yeah? Yeah. So, while there are, of course, a ton of ways to do this with your phone, most of those apps do gross things with your data. Are you angry yet?

[Jakoba the Online Witch] certainly was, or if not angry, at least annoyed. So she built a glowing egg timer, which shines a different color based on current point in her cycle, to let her know when she is fertile and expecting Aunt Flo.

The coolest part is that this is an actual egg from one of [Jakoba]’s backyard chickens. No. The coolest part is how she was able to make so many holes without breaking it. (It took four tries.)

After bleaching the insides, the egg was ready to glow. As [Jakoba] says, the guts are simple — just a Wemos D1 Mini ESP8266, a WS2812 LED, and a heatsink. The enclosure consists of an inverted peanut bowl with a glass ornament hot-glued in place.

Once it was put together, all she had to do was add it in Home Assistant and use the current calendar state to trigger services from the YAML configuration.

Would you prefer an on-body solution? Here’s an earring that tracks temperature.

An ESP Makes A Bicycle Odometer

August 7, 2024 by Jenny List 4 Comments

If you’d like to measure the speed of your cycling then it’s easy enough to buy a cycle computer, but as [Clovis Fritzen] has done it’s also an option to build one. The result of his work is a smart PCB on which the speed is indicated with a row of LEDs.

The sensor is a straightforward affair, a reed switch with a magnet on a wheel, which is sensed by an ESP8266. The six LEDs are charlieplexeed over three lines. To keep the supply voltage correct for the ESP from the uncertain state of a lithium battery, a small buck-boost module is used. Sadly the code doesn’t seem to make the speed available via the wireless part of the processor, but we’re guessing that a bit of extra software work could fix that.

The result when put in a box on the handlebars, is a smart but simple instrument that would aid any bike. It’s by no means the first one we’ve brought you and we doubt it will be the last.

A Cute Sentry Scans Your Net For Scullduggery

July 4, 2024 by Elliot Williams 10 Comments

As long as we get to make our own network security tools, why not make them look cute? Netgotchi may not be much more than an ESP8266 running network scans and offering up a honeypot service, but it smiles while sits on your desk and we think that’s swell.

Taking inspiration from a recent series of red-team devices that make hacking adorable, most obviously pwnagotchi (and arguably Flipper), Netgotchi lives on the light side of the Force. Right now, it enumerates the devices on your network and can alert you when anything sketchy joins in. We can totally imagine customizing this to include other network security or health checks, and extending the available facial expressions accordingly.

You might not always be thinking about your network, and if you’re like us, that’s probably just fine. But we love standalone displays that show one thing in an easily digestable manner, and this fits the bill, with a smile.

Quick & Capable WiFi For Your Nice-Power Supply

May 31, 2024 by Arya Voronova 15 Comments

Rejoice, those of us who have purchased a Nice-Power lab PSU from an Eastern source. Yes, the name might sound like a re-brand of a generic product, maybe you will even see this exact PSU on a shelf at a physical store near you, under a more local brand name and with a fair markup. Nevermind the circumstances, the most important part is that [Georgi Dobrishinov] found a way to add an ESP8266 to the PSU by tapping its internal UART control interface, and wrote a web UI for all your Internet-of-Lab-PSUs needs, called the PowerLinkESP project.

All you need is a Wemos D1 development board, or any other ESP8266 board that has UART pins exposed and handles 5 V input. [Georgi] brings everything else, from pictures showing you where to plug it in and where to tap 5 V, to extensive instructions on how to compile and upload the code, using just the Arduino IDE. Oh, and he tops it off with STLs for a 3D printed case, lest your Wemos D1 board flop around inside.

With [Georgi]’s software, you can monitor your PSU with interactive charts for all readings, export charts in both PNG and CSV, and access a good few features. Your ESP8266’s network uplink is also highly configurable, from an STA mode for a static lab config, to an AP mode for any on-the-go monitoring from your phone, and it even switches between them automatically! The firmware makes your PSU all that more practical, to the point that if you’re about to build an interface for your PSU, you should pay attention to [Georgi]’s work.

Lab PSUs with WiFi integration are worth looking into, just check out our review of this one; smart features are so nice to have, we hackers straight up rewrite PSU firmware to get there if we have to. Oh, and if you ever feel like standardizing your work so that it can interface to a whole world of measurement equipment, look no further than SCPI, something that’s easier to add to your project than you might expect, even with as little as Python and a Pi.