Robots are super interesting, but you probably shouldn’t start learning about them with a full-sized industrial SCARA arm or anything. Better to learn with something smaller and simpler to understand. This simple Arduino-powered robot is called Bug, and it aims to be just that.
The design comes to us from [Joshua Stanley]. It’s based around the ubiquitous Arduino Uno, paired with a motor control and I/O shield for more connectivity. The robot uses treads for locomotion—each side has two wheels wrapped in a belt for grip. The robot has a small DC gearmotor driving each belt so it can be driven forwards, backwards, and steered differentially. To perceive the world, it uses an off-the-shelf ultrasonic transceiver module, and an NRF24L01 module for remote control. All this is wrapped up in a basic 3D-printed housing that positions the ultrasonic modules effectively as “eyes” which is kind of cute, all in all.
Despite its small size and simple construction, Bug gets around perfectly well in testing on an outdoor footpath. It even has enough torque to flip itself up at full throttle. For now, [Joshua] notes it’s a glorified remote control car, but he plans to expand it further with more functionality going forward.
If you want to reverse engineer the boards in a modern console, you’d better have a lab, a lot of fancy gear, and a good few months to dedicate to the task. The humble PlayStation, on the other hand, is more accessible in this regard. [Lawrence Brode] pulled one apart and started documenting it as part of a grander quest for console understanding.
[Lawrence’s] ultimate goal is to create a portable PlayStation using original hardware. That is, rather than cannibalizing an existing console, he wants to build an original portable from scratch. He needed to understand the PlayStation to recreate it, so he started by analyzing the original hardware.
The first part of [Lawrence’s] quest was to try and reverse engineer the PlayStation motherboard itself. The 1990s console has the benefit of only using a two-layer PCB, meaning it’s far easier to trace out than more modern multi-layer designs. [Lawrence] started with a damaged console, pulled out the motherboard, and stripped off all the components. He then cleaned the board, scanned it, and then sandblasted it to remove the solder mask.
He’s begun the work of tracing out signals, and next on the agenda is to create a new custom PCB that’s compatible with the original PlayStation hardware. You can grab his work via GitHub if you’re interested. [Lawrence] is also excited about the possibilities of grabbing the 24-bit RGB signal heading into the GPU and using it for an HDMI output conversion in the future.
[Giovanni] built his energy meter to monitor energy usage in his whole home. An ESP32 serves as the heart of this build. It’s hooked up with a JSY-MK-194G energy metering module, which uses a current clamp and transformer in order to accurately monitor the amount of energy passing through the mains connection to his home. With this setup, it’s possible to track voltage, current, frequency, and power factor, so you can really nerd out over the electrical specifics of what’s going on. Results are then shared with Home Assistant via the ESPHome plugin and the ESP32’s WiFi connection. This allows [Giovanni] to see plots of live and historical data from the power meter via his smartphone.
A project like this one is a great way to explore saving energy, particularly if you live somewhere without a smart meter or any other sort of accessible usage tracking. We’ve featured some of [Giovanni’s] neat projects before, too. Video after the break.
[eigma] had a difficult problem. After pulling a TV out of the trash and bringing it home, it turned out it was suffering from a troubling boot loop issue that basically made it useless. As so many of us do, they decided to fix it…which ended up being a far bigger task than initially expected.
The TV in question was a Samsung UN40H5003AF. Powering it up would net a red standby light which would stay on for about eight seconds. Then it would flicker off, come back on, and repeat the cycle. So far, so bad. Investigation began with the usual—checking the power supplies and investigating the basics. No easy wins were found. A debug UART provided precious little information, and schematics proved hard to come by.
Eventually, though, investigation dialed in on a 4 MB SPI flash chip on the board. Dumping the chip revealed the firmware onboard was damaged and corrupt. Upon further tinkering, [eigma] figured that most of the dump looked valid. On a hunch, suspecting that maybe just a single bit was wrong, they came up with a crazy plan: use a script to brute-force flipping every single bit until the firmware’s CRC check came back valid. It took eighteen hours, but the script found a valid solution. Lo and behold, burning the fixed firmware to the TV brought it back to life.
It feels weird for a single bit flip to kill an entire TV, but this kind of failure isn’t unheard of. We’ve seen other dedicated hackers perform similar restorations previously. If you’re out there valiantly rescuing e-waste with these techniques, do tell us your story, won’t you?
The build relies on an ESP32 as the brains of the operation. It employs small 28BYJ-48 motors to run the motion platform. These were chosen as they operate on 5 V, simplifying the build by allowing everything to run off a single power supply. Along with a bunch of 3D printed parts, the motors are assembled into motion system with linear rods and belts in a CoreXY layout, chosen for speed and precision. It’s charged with moving a small magnet to drag a ball bearing through the sand to draw patterns under the command of G-code generated with the Sandify tool.
We’ve seen some great sand table builds over the years. Some use polar coordinate systems, while others repurpose bits of 3D printers. If you’ve got a creative new way of doing it, don’t hesitate to let us know!
The basic design relies on familiar components. It uses a pair of MGN15 linear rails as the basis of the motion platform, along with NEMA 17 stepper motors to run the X and Y axes. These are assembled with the aid of 3D-printed parts that bring the whole frame together, along with a pen lifter operated with a hobby servo.
The neat thing about the design is that the barebones machine is designed to sit upon an existing tabletop. This eliminates the need to integrate a large flat work surface into the plotter itself. Instead, the X axis just runs along whatever surface you place it on, rolling on a small wheel. It’s likely not ideal for accuracy or performance; we could see the machine itself skating around if run too fast. For a lightweight barebones plotter, though, it works well enough.
[Paul Junkin] bought a curious product off the Internet. It was supposed to generate electricity when hooked up to a running hose. Only, it didn’t do a very good job. His solution was straightforward—he built his own hose-powered generator that actually worked.
The design uses a turbine hooked up to a small motor acting as a generator. To maximize the transfer of energy from the stream of water to the blades of the turbine, the hose is hooked up to a convergent nozzle. [Paul] does a great job explaining the simple physics at play, as well as the iterative design process he used to get to the final product. He calculates the best-case power coming out of his hose around 50 watts, so for his turbine to collect 22 watts is a win, and it’s good enough to charge a phone or run some LED lighting.
Meet the Micro Planck. It’s a simple ortholinear mechanical keyboard in a decidedly compact form factor—measuring just 23 cm wide, 9.5 cm tall, and 2 cm deep. You could probably stuff it in your pocket if you wear baggy jeans. Oh, and if you don’t know what ortholinear means, it just means that the keys are in a straight grid instead of staggered. Kind of like those “keyboards” at the bowling alley.
The build relies on Gateron KS-33 switches installed on a custom PCB, with a ATmega32U4 microcontroller running the popular open source QMK firmware. The keyboard has a USB-C port because it’s 2024, and all the components are wrapped up in a neat 3D printed shell.
Overall, it’s a tasteful design that packs in a lot of functionality. It’s also neat to see a mechanical design used which offers more tactile feedback than the rubber dome designs more typical at this scale. Meanwhile, if you’re cooking up your own nifty keyboard designs, don’t hesitate to let us know what you’re up to!
“The Nintendo DS isn’t wide enough!” said nobody, ever. Most players found Nintendo’s form factor to be perfectly acceptable for gaming on the go, after all. Still, that doesn’t mean a handheld gaming rig with a more… cinematic aspect ratio couldn’t be fun! [Marcin Plaza] built just that, with great results.
The initial plan was to build a Steam Deck-like device, but using laptop trackpads instead of joysticks. [Marcin] had a broken Lenovo Yoga 730-13 to use as the basis for the build. That caused the plan to diverge, as the only screen [Marcin] could find that was easily compatible with the laptop’s eDP interface was an ultrawide unit. From there, a clamshell enclosure was designed specifically to rehouse all the key components from the Lenovo laptop. The top half of the clamshell would hold the screen, while the base would feature a small custom keyboard, some buttons, and the aforementioned trackpad. This thing reminds us of the Nintendo DS for multiple reasons. It’s not just the clamshell design—it’s the fact it has a touch control on the lower deck, albeit without a screen.
It’s an original concept for a handheld gaming device, and it makes us wish there were more games built for the ultrawide aspect ratio. This is one project that has us browsing the usual websites to see just what other oddball screens are out there… round screens in a makeup compact clamshell, anyone? Video after the break.
If you’re good at music theory, you can probably find all the chords and progressions you need just by using your fingers and a suitable instrument. For a lot of musicians, though, remembering huge banks of chords can be difficult, and experimenting with combinations can quickly become tedious and tiring. Enter the minichord, a tiny version of the Omnichord synth designed by [Benjamin] that offers to help out by putting all the chords you need a mere button press away.
The minichord is based around the Teensy 4.0, a capable microcontroller platform if ever there was one. It’s paired with a bunch of tactile buttons which are used to tell the Teensy which chord you desire to play. Various combinations of buttons can be used to play more advanced chords, too. There are potentiometers on board as well for volume control, as well as a touch pad for “strumming” arpeggios and other fine control tasks. An online interface allows modifying the presets onboard, too.
[Benjamin] hopes to get the minichord into production; it’s currently in a Seeedstudio competition that could see that happen, based on likes on the project video. The minichord isn’t the only player in this space, of course. The Orchard synth has been making similar waves this week. We’ve seen [Benjamin’s] work before, too. Video after the break.
Imagine you own a weather station. Then imagine that after some years have passed, you’ve had to replace one of the sensors multiple times. Your new problem is that the sensor is no longer available. What does a hacker like [Luca] do? Build a custom solution, of course!
[Luca]’s work concerns the La Crosse WS-9257F-IT weather station, and the repeat failures of the TX44DTH-IT external sensor. Thankfully, [Luca] found that the weather station’s communication protocol had been thoroughly reverse-engineered by [Fred], among others. He then set about creating a bridge to take humidity and temperature data from Zigbee sensors hooked up to his Home Assistant hub, and send it to the La Crosse weather station. This was achieved with the aid of a SX1276 LoRa module on a TTGO LoRa board. Details are on GitHub for the curious.
Luca didn’t just work on the Home Assistant integration, though. A standalone sensor was also developed, based on the Xiao SAMD21 microcontroller board and a BME280 temperature, pressure, and humidity sensor. It too can integrate with the Lacrosse weather station, and proved useful for one of [Luca’s] friends who was in the same boat.
Ultimately, it sucks when a manufacturer no longer supports hardware that you love and use every day. However, the hacking community has a way of working around such trifling limitations. It’s something to be proud of—as the corporate world leaves hardware behind, the hackers pick up the slack!
Most of us associate echolocation with bats. These amazing creatures are able to chirp at frequencies beyond the limit of our hearing, and they use the reflected sound to map the world around them. It’s the perfect technology for navigating pitch-dark cave systems, so it’s understandable why evolution drove down this innovative path.
Humans, on the other hand, have far more limited hearing, and we’re not great chirpers, either. And yet, it turns out we can learn this remarkable skill, too. In fact, research suggests it’s far more achievable than you might think—for the sighted and vision impaired alike!
Bounce That Sound
Bats are the most famous biologcal users of echolocation. Credit: Petteri Aimonen
Before we talk about humans using echolocation, let’s examine how the pros do it. Bats are nature’s acoustic engineers, emitting rapid-fire ultrasonic pulses from their larynx that can range from 11 kHz to over 200 kHz. Much of that range is far beyond human hearing, which tops out at under 20 kHz. As these sound waves bounce off objects in their environment, the bat’s specialized ultrasonic-capable ears capture the returning echoes. Their brain then processes these echoes in real-time, comparing the outgoing and incoming signals to construct a detailed 3D map of their surroundings. The differences in echo timing tell them how far away objects are, while variations in frequency and amplitude reveal information about size, texture, and even movement. Bats will vary between constant-frequency chirps and frequency-modulated tones depending on where they’re flying and what they’re trying to achieve, such as navigating a dark cavern or chasing prey. This biological sonar is so precise that bats can use it to track tiny insects while flying at speed.
Humans can’t naturally produce sounds in the ultrasonic frequency range. Nor could we hear them if we did. That doesn’t mean we can’t echolocate, though—it just means we don’t have quite the same level of equipment as the average bat. Instead, humans can achieve relatively basic echolocation using simple tongue clicks. In fact, a research paper from 2021 outlined that skills in this area can be developed with as little as a 10-week training program. Over this period, researchers successfully taught echolocation to both sighted and blind participants using a combination of practical exercises and virtual training. A group of 14 sighted and 12 blind participants took part, with the former using blindfolds to negate their vision.
The aim of the research was to investigate click-based echolocation in humans. When a person makes a sharp click with their tongue, they’re essentially launching a sonic probe into their environment. As these sound waves radiate outward, they reflect off surfaces and return to the ears with subtle changes. A flat wall creates a different echo signature than a rounded pole, while soft materials absorb more sound than hard surfaces. The timing between click and echo precisely encodes distance, while differences between the echoes reaching each ear allows for direction finding.
The orientation task involved asking participants to use mouth clicks to determine the way a rectangular object was oriented in front of them. Credit: research paperThe size discrimination task asked participants to determine which disc was bigger solely using echolocation. Credit: research paper
The training regime consisted of a variety of simple tasks. The researchers aimed to train participants on size discrimination, with participants facing two foam board disks mounted on metal poles. They had to effectively determine which foam disc was larger using only their mouth clicks and their hearing. The program also included an orientation challenge, which used a single rectangular board that could be rotated to different angles. The participants had to again use clicks and their hearing to determine the orientation of the board. These basic tools allowed participants to develop increasingly refined echo-sensing abilities in a controlled environment.
Perhaps the most intriguing part of the training involved a navigation task in a virtually simulated maze. Researchers first created special binaural recordings of a mannikin moving through a real-world maze, making clicks as it went. They then created virtual mazes that participants could navigate using keyboard controls. As they navigated through the virtual maze, without vision, the participants would hear the relevant echo signature recorded in the real maze. The idea was to allow participants to build mental maps of virtual spaces using only acoustic information. This provided a safe, controlled environment for developing advanced navigation skills before applying them in the real world. Participants also attempted using echolocation to navigate in the real world, navigating freely with experimenters on hand to guide them if needed.
Participants were trained to navigate a virtual maze using audio cues only. Credit: research paper
The most surprising finding wasn’t that people could learn echolocation – it was how accessible the skill proved to be. Previous assumptions about age and visual status being major factors in learning echolocation turned out to be largely unfounded. While younger participants showed some advantages in the computer-based exercises, the core skill of practical echolocation was accessible to all participants. After 10 weeks of training, participants were able to correctly answer the size discrimination task over 75% of the time, and at increased range compared to when they began. Orientation discrimination also improved greatly over the test period to a success rate over 60% for the cohort. Virtual maze completion times also dropped by over 50%.
Over time, participants improved in all tasks—particularly the size discrimination task, as seen in the results on this graph. The difficulty level of tasks were also scaled over time, presenting greater challenge as participants improved their echolocation skills. Credit: research paper
The study also involved a follow-up three months later with the blind members of the cohort. Participants credited the training with improving their spatial awareness, and some noted they had begun to use the technique to find doors or exits, or to make their way through strange places.
What’s particularly fascinating is how this challenges our understanding of basic human sensory capabilities. Echolocation doesn’t involve adding new sensors or augmenting existing ones—it’s just about training the brain to extract more information from signals it already receives. It’s a reminder that human perception is far more plastic than we often assume.
The researchers suggest that echolocation training should be integrated into standard mobility training for visually impaired individuals. Given the relatively short training period needed to develop functional echo-sensing abilities, it’s hard to argue against its inclusion. We might be standing at the threshold of a broader acceptance of human echolocation, not as an exotic capability, but as a practical skill that anyone can learn.
If you live near Central Park or some other local chess hub, you’re likely never short of opponents for a good game. If you find yourself looking for a computer opponent, or you just prefer playing online, you might like this LED chessboard from [DIY Machines] instead.
At heart, it’s basically a regular chessboard with addressable LEDs of the WS2812B variety under each square. The lights are under the command of an Arduino Nano, which is also tasked with reading button inputs from the board’s side panel. The Nano is interfaced with a Raspberry Pi, which is the true brains of the operation. The Pi handles chess tasks—checking the validity of moves, acting as a computer opponent, and connecting online for games against other humans if so desired. Everything is wrapped up with 3D printed parts, making this an easy project to build for the average DIY maker.
[Stephen] has a basement that depends on a sump pump. What that means is if the pump fails or the power goes out, the basement floods—which is rather undesirable. Not wanting to rely on a single point of failure, [Stephen] decided to build a monitor for the basement situation, which quickly spiralled to a greater degree of complexity than he initially expected.
The initial plan was just to have water level sensors reporting data over a modified CATS packet radio transmitter. On the other end, the plan was to capture the feed via a CATS receiver, pipe the data to the internet via FELINET, and then have the data displayed on a Grafana dashboard. Simple enough. From there, though, [Stephen] started musing on the possibilities. He thought about capturing humidity data to verify the dehumidifier was working. Plus, temperature would be handy to get early warning before any pipes were frozen in colder times. Achieving those aims would be easy enough with a BME280 sensor, though hacking it into the CATS rig was a little challenging.
The results are pretty neat, though. [Stephen] can now track all the vital signs of his basement remotely, with all the data displayed elegantly on a nice Grafana dashboard. If you’re looking to get started on a similar project, we’ve featured a great Grafana guide at a previous Supercon, just by the by. All in all, [Stephen’s] project may have a touch of the old overkill, but sometimes, the most rewarding projects are the ones you pour your heart and soul into!
Analog dials used to be a pretty common way of displaying information on test equipment and in industrial applications. They fell out of favor as more advanced display technologies became cheaper. However, if you combine an analog dial with a modern e-ink display, it turns out you get something truly fantastic indeed.
This build comes to us from [Arne]. The concept is simple—get an e-ink display, and draw a dial on it using whatever graphics and scale you choose. Then, put it behind a traditional coil-driven analog dial in place of the more traditional paper scale. Now, you have an analog dial that can display any quantity you desire. Just update the screen to display a different scale as needed. Meanwhile, if you don’t need to change the display, the e-ink display will draw zero power and still display the same thing.
[Arne] explains how it all works in the writeup. It’s basically a LilyGo T5 ESP32 board with an e-ink screen attached, and it’s combined with a MF-110A multimeter. It’s super easy to buy that stuff and start tinkering with the concept yourself. [Arne] uses it with Home Assistant, which is as good an idea as any.
You get all the benefits of a redrawable display, with the wonderful visual tactility of a real analog dial. It’s a build that smashes old and new together in the best way possible. It doesn’t heart that [Arne] chose a great retro font for the dial, either. Applause all around!
Boats normally get around with propellers or water jets for propulsion. Occasionally, they use paddles. [Engineering After Hours] claims he is “changing the boat game forever” with his new 3D printed boat design that uses a tank tread for propulsion instead. Forgive him for the hyperbole of the YouTuber. It’s basically a modified paddle design, but it’s also pretty cool.
It works on land, even if it doesn’t steer well!
The basic idea is simple enough—think “floating snowmobile” and you’re in the ballpark. In the water, the chunky tank track provides forward propulsion with its paddle-like treads. It’s not that much different from a paddle wheel steamer. However, where it diverges is that it’s more flexible than a traditional paddle wheel.
The tracked design is actually pretty good at propelling the boat in shallow water without getting stuck. In fact, it works pretty well on dirt, too! The video covers the basic concept, but it also goes into some detail regarding optimizing the design, too. Getting the float and track geometry right is key to performance, after all.
Drilling holes can be quite time consuming work, particularly if you have to drill a lot of them. Think about all the hassle of grabbing a part, fixturing it in the drill press, lining it up, double checking, and then finally making the hole. That takes some time, and that’s no good if you’ve got lots of parts to drill. There’s an easy way around that, though. Build yourself a rad jig like [izzy swan] did.
The first jig we get to see is simple. It has a wooden platter, which hosts a fixture for a plastic enclosure to slot perfectly into place. Also on the platter is a regular old power drill. The platter also has a crank handle which, when pulled, pivots the platter, runs the power drill, and forces it through the enclosure in the exact right spot. It’s makes drilling a hole in the enclosure a repeatable operation that takes just a couple of seconds. The jig gets it right every time.
The video gets better from there, though. We get to see even niftier jigs that feature multiple drills, all doing their thing in concert with just one pull of a lever. [izzy] then shows us how these jigs are built from the ground up. It’s compelling stuff.
If you’re doing any sort of DIY manufacturing in real numbers, you’ve probably had to drill a lot of holes before. Jig making skills could really help you if that’s the case. Video after the break.
If you’ve ever worked with guitar pedals or analog audio gear, you’ve probably realized the value of a resistor decade box. They substitute for a resistor in a circuit and let you quickly flick through a few different values at the twist of a knob. You can still buy them if you know where to look, but [M Caldeira] decided to build his own.
At its core, the decade box relies on a number of 11-position rotary switches. Seven are used in this case—covering each “decade” of resistances, from 1 ohm to 10 ohm and all the way up to 1 megaohm. The 11 positions on each switch allows the selection of a given resistance. For example, position 7 on the 100 ohm switch selects 700 ohms, and adds it to the total resistance of the box.
[M Caldeira] did a good job of building the basic circuit, as well as assembling it in an attractive, easy-to-use way. It should serve him well on his future audio projects and many others besides. It’s a simple thing, but sometimes there’s nothing more satisfying than building your own tools.
Whether you’re a kid or a kid at heart, learning about science and engineering can be a lot more fun if it’s practical. You could sit around learning about motors and control theory, or you could build a robot arm and play with it. If the latter sounds like your bag of hammers, you might like Pedro 2.0.
Pedro 2.0 is a simple 3D-printable robot arm intended for STEAM education. If you’re new to that acronym, it basically refers to the combination of artistic skills with education around science, technology, engineering and mathematics.
The build relies on components that are readily available pretty much around the world—SG90 servo motors, ball bearings, and an Arduino running the show. There’s also an NRF24L01 module for wireless remote control. All the rest of the major mechanical parts can be whipped up on a 3D printer, and you don’t need a particularly special one, either. Any old FDM machine should do the job just fine if it’s calibrated properly.
If you fancy dipping your toes in the world of robot arms, this is a really easy starting point that will teach you a lot along the way. From there, you can delve into more advanced designs, or even consider constructing your own tentacles. The world really is your octopus oyster.
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