Author: Bryan Cockfield

1822 Articles

Solid-State Batteries Take To The Sky

June 17, 2026 by 12 Comments

There always seem to be a handful of revolutionary technologies perpetually out of reach: fusion energy, quantum computers, and full self-driving cars are always in this list, and it seems like there’s also some battery technology which will finally let us fully decouple from fossil fuels in there as well. Although lithium batteries have allowed some ground-based electric transportation, the energy density is still not enough to enable full electrification, especially for things like aircraft. Solid state batteries may be on the verge of changing some of this, though, and a team has recently put them to work in a test aircraft to help make some headway with this novel battery chemistry.

The main contributing factor of these batteries’ improved energy densities is the ability to use a solid lithium anode, which has much higher energy density than the graphite-based anodes in modern liquid electrolyte batteries. Solid state batteries also have improved safety, since the solid electrolyte is generally not flammable and the battery itself is less prone to thermal runaway. The tests in this aircraft, a modified motorized glider, bear this out as well. With a standard lithium ion pack the team was able to harness 250 Wh/kg and with their new solid state battery they managed 410 Wh/kg, which let them fly the craft up to 24,000 feet (7,315 m) with the help of some wing-mounted solar panels.

Of course, a motorized glider is a long way away from battery-powered commercial flights, but tests like this are an important step on the way to de-carbonizing one of the more impactful industries on the planet, as well as hopefully making it less expensive to operate aircraft in the way EVs are generally much cheaper to operate than their internal combustion equivalents. But the limiting factor to adopting solid state batteries isn’t going to be implementation but rather the discovery of a cost effective way to manufacture them at scale. It’s the same reason we haven’t seen mass adoption of things like algae-based biodiesel or economic carbon capture yet.

Security Camera Gets Several Defensive Upgrades

June 16, 2026 by 19 Comments

Ever since the early web, people have been streaming video with inexpensive webcams, and since the advent of the Raspberry Pi and its dedicated camera slot we’ve really seen how easy it can be to build security cameras or any other webcam and get it online quickly. But these cameras notably lack defensive capabilities if anyone tries to break into an area they shouldn’t be, and [John] added some features to this webcam to help defend his garage.

The webcam itself is a custom build, mounted on a custom-built tilt-and-pan mount that lets it freely rotate to view any location in the garage. Some custom software running on a Raspberry Pi lets it operate in autonomous mode or be controlled manually from an Android tablet. But for the defensive capabilities, it also carries a Nerf machine gun with a laser sight and spotlights which can all be controlled autonomously by the Raspberry Pi, including a computer vision system that lets it track various objects. While this is mostly a fun novelty for his security camera, the noise it makes might be enough to startle any would-be burglar.

[John] added a few other features to this build as well, including a speaker, which allows the system to be voice-controlled and to communicate back to the user. This lets him activate and deactivate the system using a verbal password. These types of Nerf guns are fairly popular for turrets as well, and some have practical uses as well like keeping cats from walking on the kitchen counters.

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Deltarune’s Tenna Brought To Life

June 3, 2026 by 1 Comment

For those who have never played the hit video games Undertale and Deltarune, the games are partially known for their interesting characters, many of which have eerie, surreal, and expressive designs. One of the more memorable characters from Deltarune is Tenna, a game show host of sorts whose distinguishing feature is an old television as a head, as well as a colorful suit. As a result he’s been the subject of a number of recreations by various cosplayers and makers like [BigRig Creates].

This version of the character was actually inspired by a previous build by [BunnyBii] which used an iPad as the interactive screen/face. Inside the television, though, the actual human found this to be front heavy and limiting in the ways that it could be used interactively, especially since the only way to see the outside world in this version was with a small endoscope and screen. [BigRig Creates]’s version builds on this idea but swaps out the iPad for a Raspberry Pi, allowing for much more customization, and uses a pair of Xreal glasses instead of a screen for the view of the outside world from in the television.

To get the whole costume together, the head is 3D printed with all of the electronics inside, and a game controller integrated into a handheld microphone controls the animations shown on the screen. A vibrant, custom-tailored suit with white gloves rounds out the ensemble, along with a pair of 3D-printed shoe covers since actual yellow shoes were a bit pricy. There were some interesting problems to solve along the way, specifically with regards to power management for all the electronics, but in the end it all seems to have come together quite well. [BigRig Creates] is no stranger to builds with unusual displays, though; one of our favorites was the world’s largest Nintendo 3DS.

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After The Dust Settles: Building Pebble Apps

June 1, 2026 by 17 Comments

For a piece of wearable technology, Pebble has had a fairly “rocky” history. One of the most successful Kickstarters of its era, it went on to get acquired by FitBit, quietly shelved by them, then acquired by Google and open-sourced, where it’s now somewhat back in the hands of its original creator. Its new open source nature means that regular people can develop for these popular watches again, and [Coconauts] have developed a guide for these watches, new and old.

The original watches had to be coded using C, which is a fundamental language but one that generally isn’t used much in the modern world outside of embedded systems and other areas where efficieny is important. C does much less hand-holding than modern languages, so there are a number of things to keep an eye on when coding for these watches that languages like Rust, Go, and Python handle on their own. Regardless, the two-person team recently built a pair of apps for the Pebble platform as part of an app-making contest, one which notifies the user that the watch is charged to 80%, and another that shows an interactive kitten on the watch’s face.

Both of the apps are available from the Pebble app repository, and from there the source code can be found on respective GitHub pages if you’re looking for some examples to dust off old C skills. If you happen to have an old Pebble watch or always wanted one but didn’t want to deal with FitBit, now might be a good time to get them out and start tinkering around with it since it’s now in the open-source domain.

Off-Grid OCR Server Powered By IPhone

May 31, 2026 by 8 Comments

Running an optical character recognition (OCR) server might sound like it would need some powerful hardware, like a rack-mounted, water-cooled machine, or at least a nice desktop or laptop. But if you have the time, anything could be used. [Hemant] has a long-running personal project that processes a lot of image data over a long time, and set up the OCR server on an iPhone 8 running entirely with solar power, rather than turn to more typical hardware.

Part of what makes this task feasible for low-powered hardware is Apple’s Vision framework, which uses machine learning to aid in things like character recognition (among other tasks). It will run on an iPhone just as easily as a Mac. The phone’s built-in battery already provides the first step of an off-grid setup. This build relies on a separate power bank to integrate the phone with the solar panel more easily. On the software side, [Hemant] reports that the true challenge wasn’t setting up the server as much as it was keeping the iPhone from sleeping or stopping his program from running full-time.

A system like this running off-grid, especially considering the costs of the solar panel and power bank, might seem counterproductive. But when comparing electricity costs for running the same software on his server, he estimates he saves about $10 per month with this setup, which has a payback of somewhere around 2-3 years. Not too bad for a phone that would have otherwise ended up in a landfill. Old phones can be surprisingly good choices for servers, too. It helps if they can run Linux, but plenty of phones will support server applications, even when running their native OS.

Ebike Display Uses Reflective LCD

May 31, 2026 by 19 Comments

Although LCD displays have been used in almost every type of consumer electronics display over the last two decades, many of these screens have a few downsides that limit their usefulness in certain situations. As any owner of an early digital watch, an early laptop, or an early digital camera will testify, these displays often completely fail in direct sunlight. And, a currently new technology often using inexpensive displays in full sunlight conditions is ebikes, so [Volos Projects] decided to use a unique LCD display to solve this issue.

The display is called a reflective LCD (RLCD) and is actually a fairly old but overlooked piece of technology. Displays like these have a reflective layer that bounces ambient light back to the user, increasing contrast and readability in high light, especially when compared to more common transmissive displays. This build is based on a board from Waveshare, which includes the screen and its driver components, and [Volos Projects] integrated this into a test stand that mimics an ebike’s speed sensor and other hardware like turn signals. The display shows the bike’s speed and a few other indicators, and thanks to the screen, this information can be easily seen in full sun.

Although he doesn’t have it on an actual e-bike yet, he hopes it will be useful for those who want to try out something like this with their substandard e-bike displays. The code he’s used is available on a GitHub page for anyone interested. We’d imagine that a low-cost display like this would pair well with an open-source ebike like this one.

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Take The Reins Of This Unique Controller

May 29, 2026 by 6 Comments

Many simulator-style games have their own dedicated controllers, from racing sims with pedals, steering wheels, and shifters to flight sims which have their own joysticks and sometimes entire cockpits. But for how prevalent riding horses is in a wide array of video games from Red Dead Redemption to Zelda to The Witcher we’re not sure we’ve ever seen a controller built specifically for riding virtual horses, at least not until [Squalius] built this horse riding controller.

[Squalius] has been working through a few prototypes of his OpenRidingController and has a fairly complete riding setup now, complete with reins and stirrups for controlling one’s in-game companions. The reins are attached to infrared distance sensors which can send analog signals to the game for controlling steering, and are attached to each other through an elastic band to provide a more realistic feeling when both are pulled to ask the horse to stop. The stirrups can be pulled to tell the horse to move at various speeds, and although a horse doesn’t need to be commanded to jump in real life, this controller provides a method for jumping an in-game horse as well.

Although we’ve mentioned a few games famous for using horses already, [Squalius] also added a handheld joystick to enable his controller to be used in less-conventional games like Minecraft where the player can use a mod to add a horse, and has also used his controller to play DOOM as well. As its name suggests it’s also open source and the code for it is all available on the project’s GitHub page. It’s a type of controller we didn’t realize we were missing until now, and perhaps we would have expected to see one before something like a controller meant for a virtual trombone.

Thanks to [Keith] for the tip!

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