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Solid-State Batteries Take to the Sky

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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 sol...

Building And Testing A DIY Robot Actuator

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[Brandon Lai] is hoping to build a humanoid robot. To that end, he’s going to need some actuators, and decided to design his own. His second pass at this turned out pretty well, with a few snags found along the way. Target specs were a actuator that could run at 40 to 60 rpm while delivering 20 Nm of torque for up to an hour continuously. The design was inspired by an MIT research paper, with [Brandon] making a few mods to suit his use case. Where the MIT design uses an inbuilt planetary gearbox, this build substitutes a cycloidal gearbox with a hope it will provide better torque capacity with less backlash. The design is based around a hand-wound stator made with an off-the-shelf core, while using custom CNC parts and 3D printed components for the motor housing itself. Testing revealed some limitations. Running off a benchtop power supply with limited current, the motor was only able to achieve 7 Nm of torque, though a better PSU would probably improve this. [Brandon] also not...

2026 Frikkin Lasers Contest: Steampunk, 360 O-Scope Does it with Tubes

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Audiophiles all know everything sounds better fed through vacuum tubes, but did you know visualizers look better with them, too? That’s what we’re forced to conclude looking at the Tachyscope Laser, a 360-degree oscilloscope display that is [Daniel Ross]’s entry into the ongoing Frikkin Lasers contest. The diagram makes it look easier than building it probably was. The laser is a good old-fashioned helium–neon tube — something we see less and less of in this era of solid state lasers — and the wavelength gives the waveform display a retro charm. The actual display is unique in our experience, with the beam shining up through a hollow shaft to bounce off a galvanometer mirror on a spinning platform. Galvo sweeps the laser across a translucent target, which creates the waveform by persistence of vision as it spins at 100 RPM or so. Does the fact that the audio signal feeds through a tube amp to drive the single galvanometer actually improve the visuals? ...

FLOSS Weekly Episode 871: Rust Won’t Save You

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This week Jonathan chats with Florian Gilcher about Rust and Ferrous Systems! How have we gotten here, what’s coming next, and what’s new in the Rust world? Watch to find out! http://www.ferrous-systems.com http://www.ferrocene.dev http://www.oxidizeconf.com Did you know you can watch the live recording of the show right on our YouTube Channel ? Have someone you’d like us to interview? Let us know, or have the guest contact us! Take a look at the schedule here . Direct Download in DRM-free MP3. If you’d rather read along, here’s the transcript for this week’s episode . Places to follow the FLOSS Weekly Podcast: Spotify RSS Theme music: “Newer Wave” Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 4.0 License from Blog – Hackaday https://ift.tt/Qcf08Up

The Problem of Making a Good Metal-To-Glass Seal

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If you’ve ever taken a close look at a vacuum tube, you’ll have seen the seals around the pins that keep everything air-tight while providing the the device’s electrical contacts. As [maurycyz] finds out, it’s not an easy process to get right . The problem is one of both chemistry and thermal expansion, as while a good seal can be made between glass and red copper oxide, it remains very difficult indeed to stop the glass cracking on cooldown due to differing thermal expansion properties. We’re led through a variety of experiments including surface treatments and flattening the metal to a sheet, with varying pros and cons. The most successful seal on the page comes from very thin tungsten wire, though hardly the most practical conductor for a vacuum tube. It’s a fascinating investigation for the casual reader, taking them into the properties of metal-glass bonds and the difficulties involved in making them. We have even more respect for the people wh...

Smart Bulb WiFi Server Hosts “Banned” Literature

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Let’s stop for a moment and pause to consider the smart bulb. Imagine going back 20 years and telling yourself that people will be putting computers capable of acting as web servers into light bulbs just so they can control them from their telephone instead of hitting the switch. The whole thing seems crazy — but its great, because it enables hacks like this one where [RickOOOOOO] takes a commercially-available ESP32 smart bulb, and hacks it into a local file server and digital library for banned books. The word “banned” gets bandied about a lot — but assured, there’s nothing getting served up by [RickOOOOOO]’s bulb that’s going to help somebody will ill-intent build an improvised explosive device.  No, at least as conceived here, it appears to be full of easily-available e-books that were pulled from school libraries in the USA, which may-or-may not meet your personal definition of ‘banned’. Whatever you want to call them, we...

How Did They Make View-Master Slides?

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The basics of producing a stereophotograph of real life places were well-established by the time the View-Master arrived, but producing images of imaginary scenes was a bit more involved. [View Master Travels and Peter Dibble] took a look at how the fairy tale and media tie-in reels may have been made . Staring with simple dioramas, View-Master eventually developed an entire team to work on fairy tales. One of the most influential members was sculptor [ Florence Thomas ]. She was instrumental in updating many of the original fairy tale reels from small scale miniatures to 1/6 scale dioramas for the scenes. Unfortunately, the department was eventually cut and all the original miniatures thrown away. Before VCRs, View-Master was the primary way people could interact with their favorite TV shows and movies when they weren’t being broadcast. TV shows could be photographed while in production in Hollywood with a stereo camera giving great visual detail. Some cartoon and movie reels w...