A Simple Robot For Learning About Robotics

December 9, 2024 by Zoe Skyforest 6 Comments

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.

We see lots of educational robots around these parts, like this nifty little robot arm. Video after the break.

Continue reading “A Simple Robot For Learning About Robotics” →

PlayStation Motherboard Sanded And Scanned, But There’s More To Do

December 9, 2024 by Zoe Skyforest 14 Comments

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.

It’s always an exciting time in the PlayStation community; we see lots of great hacks on the regular. If you’re cooking up your own, don’t hesitate to drop us a line!

Electric Bike Uses No Electronics, Weird Motor

December 9, 2024 by Zoe Skyforest 24 Comments

E-bikes combine a bicycle with a big lithium battery, a speed controller, and a motor. What you get from that combination is simple, efficient transportation. [Tom Stanton] wanted to build an e-bike himself, but he did it without any of the fancy electronic components. But the real gem? The weird janky motor he built to run it.

The concept is simple. An e-bike is electric, in that it has an electric motor and a source of electric power. However, [Tom] intended to eliminate the electronic parts—the speed controller, any battery balancing hardware, and the like. Just think no transistors and microchips and you’ve got the right idea. Basically, [Tom] just built an e-bike with motor weak enough that it doesn’t need any fancy throttle control. He can just turn the motor hard on or off with a switch.

The bike is built around a reed switch motor. This uses magnets on a rotor, which interact with a reed switch to time pulses of electricity to coils which drive the motor. [Tom] wound the coils and built the motor from scratch using 3D printed components. The project quickly ran into problems as the reed switch began to suffer degradation from arcing, which [Tom] solved with some innovative tungsten contacts.

Controlling the bike is pretty simple—there’s just a switch connecting a capacitor bank to the motor to provide power on command. No electronics! However, [Tom] has also neatly set up the motor to charge a bank of supercapacitors when coasting downhill. In this regard, the bike can store power on a descent and then use it for a boost when required later on. Between the weird motor and the weedy capacitor bank, it doesn’t do much, but it does work.

If he’s looking for a more potent power source, perhaps the answer is already out on the street — in the form of a battery pack salvaged from the cells in discarded vapes.
Continue reading “Electric Bike Uses No Electronics, Weird Motor” →

The London Underground Is Too Hot, But It’s Not An Easy Fix

December 4, 2024 by Zoe Skyforest 92 Comments

The London Underground is an iconic piece of Victorian era engineering. What started in 1863 quickly became a core piece of infrastructure that would define the modern character of the British capital. It’s grown and changed immensely in the many years that have passed. Sadly, increasing patronage and more trains have created problems that the original designers never envisaged.

Deep in those London tunnels lies an engineering challenge. The Tube is literally cooking itself. Every day, millions of commuters descend into a network of tunnels that have been absorbing heat since the reign of Queen Victoria. Those clay-lined tubes have been soaking up excess thermal energy like a giant underground radiator, and now they’re giving it back with interest. The tunnels are simply too hot, and cooling them down is inordinately difficult.

The Perfect Storm of Thermal Chaos

The Tube’s heat problem isn’t just about one thing gone wrong – it’s about everything gone wrong at once. When Victorian engineers designed these tunnels, cooling wasn’t a major consideration. The tight, compact tunnels were built deep, nestled in the clay beneath London. In the early days, temperatures in the Underground were considered comfortably low.

“The Underground’s the only spot for comfort when the days are hot; it is cooler below.” – London Underground poster, 1926

Originally, the clay surrounding the tunnels sat at around 14°C, acting as a heat sink for the network. However, over the years, with more trains coming and going and more heat pouring in, the temperature has risen. It now typically sits anywhere from 19° to 26 °C. That’s just the earth around the tunnels, though. Air temperatures are worse—hitting as high as 47°C during a 2006 heatwave. The problem has been a continual bugbear of the beloved Tube, with concerns that future heatwaves could see temperatures rise ever higher. Continue reading “The London Underground Is Too Hot, But It’s Not An Easy Fix” →

Scratch And Sniff Stickers And The Gas Panic Of ’87

December 3, 2024 by Zoe Skyforest 41 Comments

Ever wonder how those scratch and sniff stickers manage to pack a punch of aroma into what looks like ordinary paper? The technology behind it is deceptively clever, and has been used everywhere from children’s books to compact discs.

Most Scratch and Sniff stickers are simple nose-based novelties, though they’ve seen other uses as diagnostic tools, too. As Baltimore Gas and Electric discovered in 1987, though, these stickers can also cause a whole lot of hullabaloo. Let’s explore how this nifty technology works, and how it can go—somewhat amusingly—wrong.

The Science

3M developed the scratch and sniff technology in the 1960s. It quickly gained iconic status in the decades that followed. via eBay

At its heart, scratch and sniff technology involves the microencapsulation of tiny smellable particles, which are then impregnated into stickers or other paper products. Microscopic amounts of aromatic materiale are trapped inside gelatin or plastic capsules, and then stuck to paper. When you scratch the surface, these capsules rupture, releasing their aromatic cargo into the air. It’s an elegant feat of materials engineering, originally developed by Gale W. Matson. Working at 3M in the 1960s, he’d been intending to create a new kind of carbonless copy paper.

Scratch and Sniff stickers soon became a popular novelty in the 1970s. The catchy name was perfect—it told you everything you need to know. A children’s book named Little Bunny Follows His Nose was one of the first widespread applications. Released in 1971, it was entirely based around the whole scratch and sniff concept. Children could read along and scratch various illustrations of peaches, roses and pine needles to see what they smelled like. The book was reprinted multiple times, remaining in publication for over three decades.

Other popular media soon followed. Pop rock band The Raspberries put a scratch and sniff sticker on their album cover in 1972. Director John Waters would go on to release his 1981 film Polyester with an accompanying “Odorama” card, which featured multiple smells for viewers to sniff during the movie. The concept still resurfaces occasionally, though the gimmick is now well-worn. In 2010, Katy Perry’s Teenage Dream album smelled like cotton candy thanks to a scratch-and-sniff treatment on the Deluxe Edition, and King Gizzard & The Lizard Wizard put a similar touch on 2017’s Flying Microtonal Banana. Continue reading “Scratch And Sniff Stickers And The Gas Panic Of ’87” →

ESP32 Powers DIY Smart Energy Meter

December 2, 2024 by Zoe Skyforest 20 Comments

Energy is expensive these days. There’s no getting around it. If, like [Giovanni], you want to keep better track of your usage, you might find value in his DIY energy meter build.

[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.
Continue reading “ESP32 Powers DIY Smart Energy Meter” →

Saving A Samsung TV From The Dreaded Boot Loop

November 30, 2024 by Zoe Skyforest 39 Comments

[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?