A side view of an Asian woman with brown hair. She has a faint smile and is wearing an earring that looks somewhat like a large copper snowflake. Near the ear hole is a small PCB with a blinking LED. To the right of the image is the text "LED Earring, Recieved power 50 µW"

Power-Over-Skin Makes Powering Wearables Easier

November 4, 2024 by Navarre Bartz 33 Comments

The ever-shrinking size of electronics and sensors has allowed wearables to help us quantify more and more about ourselves in smaller and smaller packages, but one major constraint is the size of the battery you can fit inside. What if you could remotely power a wearable device instead?

Researchers at Carnegie Mellon University were able to develop a power transmitter that lets power flow over human skin to remote devices over distances as far a head-to-toe. The human body can efficiently transmit 40 MHz RF energy along the skin and keeps this energy confined around the body and through clothing, as the effect is capacitive.

The researchers were able to develop several proof-of-concept devices including “a Bluetooth
ring with a joystick, a stick-and-forget medical patch which logs data, and a sun-exposure patch with a screen — demonstrating user input, displays, sensing, and wireless communication.” As the researchers state in the paper, this could open up some really interesting new wearable applications that weren’t possible previously because of power constraints.

If you’re ready to dive into the world of wearables, how about this hackable smart ring or a wearable that rides rails?

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Three 3D printed, spring loaded contraptions sit on a wooden shield. There are arrow shafts connected to the end and a piece of monofilament fishing line extending away from them and through a small eyelet at the edge of. the shield.

How To Shoot Actors With Arrows Sans CGI

November 4, 2024 by Navarre Bartz 20 Comments

Today, movie effects are mostly done in CGI, especially if they’re of the death-defying type. [Tyler Bell] shows us how they shot actors with arrows before CGI.

Almost every medieval movie has someone getting shot with an arrow, but how do you do that non-destructively? [Bell] shows us two primary methods that were used, the pop up rig and steel pronged arrows. The pop up rig is a spring loaded device with one end of an arrow attached that pops up when a mechanism is triggered. [Bell] 3D printed his own version of the mechanism and shows us how it can be used to great effect on shots from the side or rear of the victim.

But what about straight on shots where the rig would be blatantly obvious? That’s when you get to actually shoot the actor (or their stunt double anyway). To do this safely, actors would wear wooden body armor under their costumes and arrows with two small prongs would be shot along a wire into the desired impact site. We appreciate [Bell] using a mannequin for testing before letting his brother shoot him with an arrow. That’s definitely the next level above a trust fall.

We even get a look at using air cannons to launch arrow storms at the end which is particularly epic. Looking for more movie magic? How about the effects from King Kong or Flight of the Navigator?

Thanks to [Xerxes3rd] on Discord for the tip!

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A white handheld with a centered screen and Xbox-style controllers flanking an 8" screen. Speaker grilles are visible below the controllers in the face of the device.

Beth Deck Is A Framework-Powered Gaming Handheld

November 3, 2024 by Navarre Bartz 22 Comments

DIY gaming handhelds have long been the purview of the advanced hacker, with custom enclosures and fiddly soldering making it a project not for the faint of heart. [Beth Le] now brings us a custom handheld for the beginner that can be assembled in 15 minutes and doesn’t require any soldering.

These claims might seem suspicious at first, but the fact that the build is powered by a Framework mainboard makes the dream seem attainable. Using an 8″ touchscreen and a rehoused mobile device controller, the 3D printed enclosure turns the PCB and battery into an interesting alternative to a Steam Deck.

[Beth] recommends waiting for the forthcoming revision 2 to make your own as she is working on refining the model. She also suggests printing in PC or PETG since PLA is too brittle and ABS warping can be an issue for tolerances with the pogo pins. In any case, this is definitely a project to keep your eye on if you enjoy gaming on the go.

As you know, we love Framework around here and the Cambrian Explosion of high-powered custom builds it’s enabled. This isn’t the first time we’ve seen a Framework-Powered handheld either. If you’re looking for a different form factor, we’ve also seen portable all-in-ones, keyboard PCs, and slabtops too.

White pieces on a teal and white chess board. The line of pawns shows three segmented queens in the foreground, one piece being pressed by a man's hand from above in a state between queen and pawn, and the remainder of the pawns in the background in the pawn state.

Transforming Pawn Changes The Game

November 2, 2024 by Navarre Bartz 14 Comments

3D printing has allowed the hobbyist to turn out all sorts of interesting chess sets with either intricate details or things that are too specialized to warrant a full scale injection molded production run. Now, the magic of 3D printing has allowed [Works By Design] to change the game by making pawns that can automatically transform themselves into queens.

Inspired by a CGI transforming chess piece designed by [Polyfjord], [Works By Design] wanted to make a pawn that could transform itself exist in the real world. What started as a chonky setup with multiple springs and a manually-actuated mechanism eventually was whittled down to a single spring, some pins, and four magnets as vitamins for the 3D printed piece.

We always love getting a peek into the trial-and-error process of a project, especially for something with such a slick-looking final product. Paired with a special chess board with steel in the ends, the magnets in the base activate the transformation sequence when they reach the opposite end.

After you print your own, how about playing chess against the printer? We’d love to see a version machined from metal too.

Thanks to [DjBiohazard] on Discord for the tip!

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An exploded view of an electrostatic motor from manufacturer C-Motive. There is a silvery cylinder on the left, two half silver and half golden disks on either side and two thinner gold disks in the center. A square mountin plate is on the right hand side next to one of the silver/gold disks.

Electrostatic Motors Are Making A Comeback

October 29, 2024 by Navarre Bartz 21 Comments

Electrostatic motors are now common in MEMS applications, but researchers at the University of Wisconsin and spinoff C-Motive Technologies have brought macroscale electrostatic motors back. [via MSN/WSJ]

While the first real application of an electric motor was Ben Franklin’s electrostatically-driven turkey rotisserie, electromagnetic type motors largely supplanted the technology due to the types of materials available to engineers of the time. Newer dielectric fluids and power electronics now allow electrostatic motors to be better at some applications than their electromagnetic peers.

The main advantage of electrostatic motors is their reduced critical materials use. In particular, electrostatic motors don’t require copper windings or any rare earth magnets which are getting more expensive as demand grows for electrically-powered machines. C-Motive is initially targeting direct drive industrial applications, and the “voltage driven nature of an electrostatic machine” means they require less cooling than an electromagnetic motor. They also don’t use much if any power when stalled.

Would you like a refresher on how to make static electricity or a deeper dive on how these motors work?

Asahi Linux Brings Better Gaming To Apple Silicon

October 29, 2024 by Navarre Bartz 8 Comments

For those of you longing for better gaming on an Apple Silicon device, Asahi Linux is here to help.

While Apple’s own line of CPUs are relatively new kids on the block, they’ve still been around for four years now, giving hackers ample time to dissect their innards. The team behind Asahi Linux has now brought us “the only conformant OpenGL®, OpenCL™, and Vulkan® drivers” for Apple’s M1 and M2.

The emulation overhead of the system means that most games will need at least 16 GB of RAM to run. Many games are playable, but newer titles can’t yet hit 60 frames per second. The developers are currently focused on “correctness” and hope to improve performance in future updates. Many indie titles are reported to already be working at full speed though.

You can hear more about some of the fiddly bits of how to “tessellate with arcane compute shaders” in the video below. Don’t worry, it’s only 40 minutes of the nine hour video and it should start right at the presentation by GPU dev [Alyssa Rosenzweig].

If you want to see some of how Linux on Apple Silicon started or some of the previous work on hacking the M1 GPU, we have you covered.

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Mini Robotic Arm Lets You Start Your Own Mini Assembly Line

October 24, 2024 by Navarre Bartz 25 Comments

Automating tasks with a robot sounds appealing, but not everyone has the budget for an Aismo or Kuka. [FABRI Creator] has a great tutorial on how to build your own mini robotic arm for small, repeatable tasks.

Walking us through the entire build, step-by-step, [FABRI Creator] shows us how to populate the custom-designed PCB and where to put every servo motor and potentiometer to bring the creation to life. This seems like a great project to start with if you haven’t branched out into motion systems before since it’s a useful build without anything too complicated to trip up the beginner.

Beyond the usual ability to use the arm to perform tasks, this particular device uses an Arduino Nano to allow you to record a set of positions as you move the arm and to replay it over and over. The video shows the arm putting rings on a stand, but we can think of all kinds of small tasks that it could accomplish for us, letting us get back to writing or hacking.

If controlling a robot arm with potentiometers sounds familiar, maybe you remember this robot arm with an arm-shaped controller.

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