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192 Articles

Hackaday.io Low-Power Challenge Begins Today

January 24, 2023 by 23 Comments

How low can you go? The 2023 Hackaday.io Low-Power Challenge is about doing the most with the least juice – bang for the power-budget buck, if you get our drift. And with three $150 gift certificates from Digi-Key on the line, you’ll be able to keep your projects going forever. The Challenge runs until March 21st, but with low-power, the devil is often in the details, so get started today!

More and more projects need to run on their own power, and more often than not, that means getting by without access to a wall plug. This contest is to encourage your designs that run on solar, small batteries, and generally energy harvested from wherever you can get it. But the power generation mechanism is taking the back seat here – we want to see what you can do with a few good electrons. Surprise us with your maximum minimalism!

Continue reading “Hackaday.io Low-Power Challenge Begins Today” →

Showing the end result car, with mechanum wheels and a green chassis with what seems to be a camera window on top

2022 FPV Contest: ESP32-Powered FPV Car Uses Javascript For VR Magic

December 30, 2022 by 5 Comments

You don’t always need much to build an FPV rig – especially if you’re willing to take advantage of the power of modern smartphones. [joe57005] is showing off his VR FPV build – a fully-printable small Mechanum wheels car chassis, equipped with an ESP32-CAM board serving a 720×720 stream through WiFi. The car uses regular 9g servos to drive each wheel, giving you omnidirectional movement wherever you want to go. An ESP32 CPU and a single low-res camera might not sound like much if you’re aiming for a VR view, and all the ESP32 does is stream the video feed over WebSockets – however, the simplicity is well-compensated for on the frontend. Continue reading “2022 FPV Contest: ESP32-Powered FPV Car Uses Javascript For VR Magic” →

The assembled switch PCB in the palm of its creator's hand

TTP223 Brings Simple Touch Controls To A LED Lamp

October 4, 2022 by 7 Comments

You can buy small modules with capacitive touch detection ICs — most often it’s the TTP223, a single-button capacitive model with configurable output modes. These are designed to pair with a microcontroller or some simple logic-level input, but [Alain Mauer] wanted was to bring touch control to a simple LED strip. Not to be set deterred, he’s put together a simple TTP223-based switch board.

Initially, he made a prototype using one of the regular TTP223 boards as a module, but then transferred the full schematic onto a single PCB. The final board uses an NPN transistor capable of handling up to 3 amps to do the switching job, and Zener-based regulation to provide 5 V for the TTP223 itself from the 12 V input. [Alain] shares the schematic, as well as BOM together with Gerber files for a 2×3 panel in case you’re interested in adding a few of these handy boards to your parts bin.

The TTP223 is a ubiquitous and quite capable chip – we’ve seen it used for building a mouse with low actuation force buttons, a soft power switch, and even a UV-sensing talisman that’s equal parts miniature electronics and fascinating metalwork.

Continue reading “TTP223 Brings Simple Touch Controls To A LED Lamp” →

Screenshot of a logic analyzer software, showing the SDA channel being split into three separate traces

I2C Tap Helps Assign Blame For SDA Conflicts

May 2, 2022 by 8 Comments

If you’ve ever debugged a misbehaving I2C circuit, you probably know how frustrating it can be. Thankfully [Jim] over at Hackaday.io, has a proto-boardable circuit that can help!

Inter-integrated circuit bus (aka I2C) uses open collector outputs on a two wire interface. Open collector means a device connected to the I2C bus can only pull the bus down to ground. Chips never drive a logic “HIGH” on the wires. When nothing is driving the lines low, a weak resistor pulls the lines up to VCC. This is a good thing, because I2C is also a multidrop bus — meaning many devices can be connected to the bus at the time. Without open collector outputs, one chip could drive a high, while another drives a low – which would create a short circuit, possibly damaging both devices.

Even with all this protection, there can be problems. The SCL and SDA lines in the I2C communication protocol are bidirectional, which means either a controller or a peripheral can pull it low. Sometimes, when tracing I2C communications you’ll need to figure out which part is holding the line low. With many devices sharing the same bus, that can become nigh-impossible. Some folks have tricks with resistors and analog sampling, but the tried and true method of de-soldering and physically lifting chip pins off the bus often comes into play.

[Jim’s] circuit splits SDA signal into controller-side and peripheral-side, helping you make it clear who is to blame for hiccups and stray noise. To do that, he’s using 6N137 optoisolators and LMV393 comparators. [Jim] shared a NapkinCAD schematic with us, meant to be replicate-able in times of dire need. With this design, you can split your I2C bus into four separate channels – controller-side SDA, peripheral-side SDA, combined SDA and SCL. 4 Channels might be a lot for a scope, but this is no problem for today’s cheap logic analyzers.

Continue reading “I2C Tap Helps Assign Blame For SDA Conflicts” →

The Tracer board strapped to the frame of a bicycle with a red Velcro strap

Tracer, A Platform For All Things Movement Logging

April 1, 2022 by 2 Comments

[elektroThing] is building a lightweight, battery-powered board to track and measure movement of all kinds, called Tracer. Powered by an ESP32, it has a LSM6DSL 6DoF accelerometer & gyroscope sensor, and a VL53L0X Time-of-Flight sensor. A small Li-ion battery in a holder reportedly provides for 5 hours of streaming data over Bluetooth Low Energy (BLE) at 100 Hz. It’s essentially a wireless movement sensor platform to be paired with a more powerful computer for data logging and analysis. What’s such a platform good for?

They show it attached to a tennis racket, saying you could use the data to, for a start, count the strokes done in a given match. They’ve also strapped it to a bicycle’s crankshaft and used it as a cadence sensor – good for gauging your cycling efficiency! But of course, this can be used in more applications than sport. A device like this could be used for logging movement of any relatively nearby objects, be it your cat, an office chair, or a door someone might slam a bit too hard at times. Say, you wanted to develop a sleep tracker and were to collect some data for defining your algorithms and planning your hardware requirements – this would work wonders.

There’s already available example code for streaming data into the Phyphox data logging and graphing app, as well as schematics – hopefully, the full board files will be available soon. A worthy open-source opponent to commercial devices available for similar purposes, this platform is good news for any hacker that wants to do motion measurement projects without reinventing quite a few wheels at once. We are told this board might get to CrowdSupply soon, and we can’t wait! Platforms like these, if done well, can grow an offspring of new projects for us to have fun with, and our paid projects get all that much easier to work on.

We’ve shown projects with such sensors before – here’s one that helps your rifle aim by giving you data to debug your last-second rifle movements, and another that logs movement data from inside a football. There’s a million endpoints you could stream your data into, and we are told you could even use Google Sheets. Just a year ago, we held our Data Logging contest and the entries we received will surely point out quite a few under-explored areas in your daily life!

The octagonal wooden box described in the project. On the left, outer surface of the box is shown, with "Say Friend And Come In" inscription, as well as a few draings (presumably from Lord of The Rings) and two metallic color stars that happen to serve as capacitative sensor electrodes. On the right, underside of the lid is shown, with all the electronics involved glued into CNC-machined channels.

Say Friend And Have This Box Open For You

March 28, 2022 by 13 Comments

Handcrafted gifts are special, and this one’s no exception. [John Pender] made a Tolkien-inspired box for his son and shared the details with us on Hackaday.io. This one-of-a-kind handcrafted box fulfills one role and does it perfectly – just like with the Doors of Durin, you have to say ‘friend’ in Elvish, and the box shall unlock for you.

This box, carefully engraved and with attention paid to its surface finish, stands on its own as a gift. However, with the voice recognition function, it’s a project complicated enough to cover quite a few fields at once – woodworking, electronics, and software. The electronics are laid out in CNC-machined channels, and LED strips illuminate the “Say Friend And Come In” inscriptions once the box is ready to listen. If you’re wondering how the unlocking process works, the video embedded below shows it all.

Two solenoids keep the lid locked, and in its center is a Pi Zero, the brains of the operation. With small batteries and a power-hungry board, power management is a bit intricate. Two capacitive sensors and a small power management device are always powered up. When both of the sensors are touched, a power switch module from Pololu wakes the Pi up. It, in turn, takes its sweet time, as fully-fledged Linux boards do, and lights up the LED strip once it’s listening.

Continue reading “Say Friend And Have This Box Open For You” →

Announcing: The 2022 Hackaday.io Sci-Fi Contest

March 10, 2022 by 6 Comments

Ladies and Gentlemen, Sentient robots, Travellers from the distant future, or Aliens from the outer rim, it’s time to enter the 2022 Hackaday.io Sci-Fi Contest!

We last ran the Sci-Fi contest in the far, far past — before the Voigt-Kampff machine was detecting replicants on the gritty streets of 2019’s LA. Back then, we had some out-of-this-world entries. It’s time for the sequel.

Thanks to Digi-Key, the contest’s sponsor, your best blaster, your coolest costume, or your most righteous robot could win you one of three $150 shopping sprees in their parts warehouse. Create a Hackaday.io project, enter it in the contest, and you’re set. You might as well do that right now, but the contest closes on April 25th.

Sci-Fi is all about the looks, so if it’s purely decorative, be sure to blind us with science (fiction). If your project actually functions, so much the better! Of course we’d like to know how it works and how you made it, so documentation of the project is the other big scoring category. Whatever it is, it’s got to be sci-fi, and it’s got to have some electronics in it.

If you’re looking for inspiration, you could do a lot worse than to check out [Jerome Kelty]’s Animatronic Stargate Helmet, that not coincidentally took the grand prize last time around. It’s an artistic and engineering masterpiece all rolled into one, and the description of how it’s made is just as extensive. [Jochen Alt]’s “Paul” robot isn’t out of any particular sci-fi franchise that we know, but of rolling on one ball and reciting robot poetry, it absolutely should be.

Honorable Mentions

In addition to the overall prizes, we’ll be recognizing the best projects in the following honorable mention categories:

  • Star Star: Whether you’re “beam me up” or “use the force”, fans of either of the “Star” franchises are eligible for this honorable mention.
  • ExoSuit: This category recognizes sci-fi creations that you can wear. Costumes and armor fit in here.
  • Stolen off the Set: If your blaster looks exactly like Han Solo’s, you’re a winner here.  This is the category for your best prop replica.
  • Living in the Future: If your sci-fi device was purely fantasy when imagined, but now it’s realizable, you’re living in the future. A working tricorder or a functioning robot companion would fit in fine here.
  • The Most Important Device: Has no function, but it certainly looks like it does. Just blinking lights that blink back and forth, yet the government spent millions of dollars on it.

You don’t have to tell us where your project fits in. We’ve got you covered.

Engage!

Get started now by creating a project page on Hackaday.io. In the left sidebar of your project page, use the “Submit Project To” button to enter in the 2022 Sci-Fi Contest.

You have from now until April 25, 2022 to get it finished. Of course, if your time machine actually works, you can finish it whenever. Check out the Hackaday.io contest page for all the fine print.