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Hackaday Links: June 22, 2025

June 22, 2025 by 16 Comments

Hold onto your hats, everyone — there’s stunning news afoot. It’s hard to believe, but it looks like over-reliance on chatbots to do your homework can turn your brain into pudding. At least that seems to be the conclusion of a preprint paper out of the MIT Media Lab, which looked at 54 adults between the ages of 18 and 39, who were tasked with writing a series of essays. They divided participants into three groups — one that used ChatGPT to help write the essays, one that was limited to using only Google search, and one that had to do everything the old-fashioned way. They recorded the brain activity of writers using EEG, in order to get an idea of brain engagement with the task. The brain-only group had the greatest engagement, which stayed consistently high throughout the series, while the ChatGPT group had the least. More alarmingly, the engagement for the chatbot group went down even further with each essay written. The ChatGPT group produced essays that were very similar between writers and were judged “soulless” by two English teachers. Go figure.

Continue reading “Hackaday Links: June 22, 2025” →

A green box with the answer to if a nuke has gone off with red neon lights

Has A Nuke Gone Off? Indicator

June 22, 2025 by 23 Comments

Look out of a window, ask yourself the question, “Has a nuke gone off?”. Maybe, maybe not, and all of us here at Hackaday need to know the answer to these important questions! Introducing the hasanukegoneoff.com Indicator from [bigcrimping] to answer our cries.

An ESP32 running a MicroPython script handles the critical checks from hasanukegoneoff.com for any notification of nuclear mayhem. This will either power the INS-1 neon bulb, indicating “no” or “yes” in the unfortunate case of a blast. Of course, there is also the button required for testing the notification lights; no chance of failure can be left. All of this is fitted onto a custom dual-sided PCB and placed inside a custom 3D-printed enclosure.

Hasanukegoneoff.com’s detection system, covered before here, relies on an HSN-1000L Nuclear Event Detector to check for neutrons coming from the blast zone. [bigcrimping] also provides the project plans for your own blast detector to answer the critical question of “has a nuke gone off” from anywhere other than the website’s Chippenham, England location.

This entire project is open sourced, so keep sure to check out [bigcrimping]’s GitHub for both portions of this project on the detector and receiver. While this project provides some needed dark humor, nukes are still scary and especially so when disarming them with nothing but a hacksaw and testing equipment.

Thanks to [Daniel Gooch] for the tip.

Drone Photogrammetry

Photogrammetry Takes To The Skies

June 22, 2025 by 14 Comments

Maybe your goal is to preserve the heyday of rail travel with a precise scale replica of a particular railroad station. Maybe you’re making a hyper-local edition of Monopoly in which the houses and hotels are the actual houses and hotels in your hometown.

Whatever the reason, if you have need for shrinkifying a building or other reasonably large object, there is (at least) one sure-fire way to do it, and [ nastideplasy ] is your guide with this tutorial on drone photogrammetry.

The process is essentially the same as any other photogrammetry you may have seen before—take lots of overlapping photos of an object from many different angles around it, stitch those photos together, make a 3D mesh by triangulating corresponding points from multiple photos—but this time the photos are captured by drone, allowing for much larger subjects, so long as you can safely and legally fly a drone around it.

The challenge, of course, is capturing a sufficient number of overlapping photos such that your reconstruction software can process them into a clean 3D mesh. Where purpose-built 3D scanners, automatic turntables, or a steady hand and lots of patience worked well at a smaller scale, skill with a pair of control sticks is the key to getting a good scan of a house.

[ nastideplasy ] also points out the importance of lighting. Direct sunlight and deep shadows can cause issues when processing the images, and doing this at night is almost certainly out of the question. Overcast days are your best bet for a clean scan.

The tutorial calls for software from Autodesk to stitch photos and clean up 3D meshes. We’ve also seen some excellent results with open source options like Meshroom as well.

A C-shaped wooden frame is shown surrounding a circular tongue drum. The wooden frame holds eight black adjustable arms, at the ends of which are mounted solenoids, positioned just above the surface of the drum.

Giving A Drum MIDI Input With Lots Of Solenoids

June 22, 2025 by 7 Comments

As far as giving mechanical instruments electronic control goes, drums are probably the best candidate for conversion; learning to play them is challenging and loud for a human, but they’re a straightforward matter for a microcontroller. [Jeremy Cook]’s latest project takes this approach by using an Arduino Opta to play a tongue drum.

[Jeremy]’s design far the drum controller was inspired by the ring-shaped arrangement of the Cray 2 supercomputer. A laser-cut MDF frame forms a C-shape around the tongue drum, and holds eight camera mount friction arms. Each friction arm holds a solenoid above a different point on the drum head, making it easy to position them. A few supports were 3D-printed, and some sections of PVC tubing form pivots to close the ring frame. [Jeremy] found that the the bare metal tips of the solenoids made a harsh sound against the drum, so he covered the tips of six solenoids with plastic caps, while the other two uncoated tips provide an auditory contrast.

The Arduino Opta is an open-source programmable logic controller normally intended for industrial automation. Here, its silent solid-state relays drive the solenoids, as [Jeremy]’s done before in an earlier experiment. The Opta is programmed to accept MIDI input, which [Jeremy] provided from two of the MIDI controllers which we’ve seen him build previously. He was able to get it working in time for the 2024 Orlando Maker Faire, which was the major time constraint.

Of course, for a project like this you need a MIDI controller, and we’ve previously seen [Jeremy] convert a kalimba into such a controller. We’ve seen this kind of drum machine at least once before, but it’s more common to see a purely electronic implementation.

Tektronix TDS8000 banner

Repairing An Old Tektronix TDS8000 Scope

June 22, 2025 by 3 Comments

Over on his YouTube channel our hacker [CircuitValley] repairs an old TDS8000 scope.

The TDS8000 was manufactured by Tektronix circa 2001 and was also marketed as the CSA8000 Communications Signal Analyzer as well as the TDS8000 Digital Sampling Oscilloscope. Tektronix is no longer manufacturing and selling these scopes but the documentation is still available from their website, including the User Manual (268 page PDF), the Service Manual (198 page PDF), and some basic specs (in HTML).

You can do a lot of things with a TDS8000 scope but particularly its use case was Time-Domain Reflectometry (TDR). A TDR scope is the time-domain equivalent of a Vector Network Analyzer (VNA) which operates in the frequency-domain.

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A man is shown performing a wheelie on a red bicycle in a classroom. In the background, a projector is displaying a phone screen running an indistinct app.

An Adaptive Soundtrack For Bike Tricks

June 22, 2025 by 7 Comments

If you’ve put in all the necessary practice to learn bike tricks, you’d probably like an appropriately dramatic soundtrack to accompany your stunts. A team of students working on a capstone project at the University of Washington took this natural desire a step further with the Music Bike, a system that generates adaptive music in response to the bike’s motion.

The Music Bike has a set of sensors controlled by an ESP32-S3 mounted beneath the bike seat. The ESP32 transmits the data it collects over BLE to an Android app, which in turn uses the FMOD Studio adaptive sound engine to generate the music played. An MPU9250 IMU collects most position and motion data, supplemented by a hall effect sensor which tracks wheel speed and direction of rotation.

When the Android app receives sensor data, it performs some processing to detect the bike’s actions, then uses these to control FMOD’s output. The students tried using machine learning to detect bike tricks, but had trouble with latency and accuracy, so they switched to a threshold classifier. They were eventually able to detect jumps, 180-degree spins, forward and reverse motion, and wheelies. FMOD uses this information to modify music pitch, alter instrument layering, and change the track. The students gave an impressive in-class demonstration of the system in the video below (the demonstration begins at 4:30).

Surprisingly enough, this isn’t the first music-producing bike we’ve featured here. We’ve also seen a music-reactive bike lighting system.

Thanks to [Blake Hannaford] for the tip!

Tamagotchi Torture Chamber Is Equal Parts Nostalgia And Sadism

June 21, 2025 by 8 Comments

Coming in hot from Cornell University, students [Amanda Huang], [Caroline Hohner], and [Rhea Goswami] bring a project that is guaranteed to tickle the funny bone of anyone in the under-40 set, and sadists of all ages: The Tamagochi Torture Chamber.

Tamagotchi Torture Chamber displaying Tombstone
He’s dead, Jim.

In case you somehow missed it, Bandai’s Tamagochi is a genre-defining digital pet that was the fad toy at the turn of the millennium, and has had periodic revivals since. Like the original digital pet, there are three pushbuttons to allow you to feed, play with, and clean your digital pet. These affect the basic stats of happiness, health, food and weight in ways that will be familiar to anyone who played with the original Tamagochi. Just as with the original, mistreatment or neglect causes the Tamagochi to “die” and display a tombstone on the TFT display.

Where the “Torture Chamber” part comes in is the presence of an accelerometer and soft physics simulation– the soft physics gets an entire core of the Pi Pico at the heart of this build dedicated to it, while the other core handles all inputs, display and game logic. What this enables is the ability to bounce the digital pet off the walls of its digital home with an adorable squish (and drop in health stat) by tilting the unit. You can check that out in the demo video blow.

Is it overkill for a kids toy to have a full soft body simulation, rather than just a squish-bounce animation? Probably, but for an ECE project, it lets the students show off their chops… and possibly work out some frustrations.

We won’t judge. We will point you to other Tamagotchi-inspired projects, though: like this adorable fitness buddy, or this depressingly realistic human version.

If you’ve got an innovative way to torture video game characters, or a project less likely to get you on Skynet’s hitlist, don’t forget to send in a tip!

Continue reading “Tamagotchi Torture Chamber Is Equal Parts Nostalgia And Sadism” →