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?

If you’re into pushing tech boundaries from home, this one’s for you. Redditor [mi_kotalik] has crafted ‘Zero’, a custom pair of DIY augmented reality (AR) glasses using a Raspberry Pi Zero. Designed as an affordable, self-contained device for displaying simple AR functions, Zero allows him to experiment without breaking the bank. With features like video playback, Bluetooth audio, a teleprompter, and an image viewer, Zero is a testament to what can be done with determination and creativity on a budget. The original Reddit thread includes videos, a build log, and links to documentation on X, giving you an in-depth look into [mi_kotalik]’s journey. Take a sneak peek through the lens here.

Creating Zero wasn’t simple. From designing the frame in Tinkercad to experimenting with transparent PETG to print lenses (ultimately switching to resin-cast lenses), [mi_kotalik] faced plenty of challenges. By customizing SPI displays and optimizing them to 60 FPS, he achieved an impressive level of real-time responsiveness, allowing him to explore AR interactions like never before. While the Raspberry Pi Zero’s power is limited, [mi_kotalik] is already planning a V2 with a Compute Module 4 to enable 3D rendering, GPS, and spatial tracking.

Zero is an inspiring example for tinkerers hoping to make AR tech more accessible, especially after the fresh news of both Meta and Apple cancelling their attempts to venture in the world of AR. If you are into AR and eager to learn from an original project like this one, check out the full Reddit thread and explore Hackaday’s past coverage on augmented reality experiments.

Unless you spend all your time lounging on the sofa, you probably own at least one pair of shoes. But have you ever thought to make your own to improve some aspect of your life? YouTube channel Answer in Progress set out to do precisely that, but it didn’t quite work out.

When you (well, other people) get into running, it’s tempting to believe a lot of the shoe company hype and just drop hundreds of dollars on the latest ‘super shoe’ and hope that will help you break your target time. But do you actually need to buy into all this, or can you make something yourself? The project aimed to get the 5k time down significantly, at any cost, but primarily by cheating with technology. The team set out to look at the design process, given that there is indeed a fair amount of science to shoe design. Firstly, after a quick run, the main issues with some existing shoes were identified, specifically that there are a lot of pain points; feet hurt from all the impacts, and knees take a real pounding, too. That meant they needed to increase the sole cushioning. They felt that too much energy was wasted with the shoes not promoting forward motion as much as possible; feet tended to bounce upwards so that a rocker sole shape would help. Finally, laces and other upper sole features cause distraction and some comfort issues, so those can be deleted.

The plan was to make a ‘sock’ shoe style, with an upper in one piece and stretchy enough to slip on without laces. The process started by wrapping the foot in cling film and then a few layers of duct tape to fix the shape. This was split down the top to extract the foot, open out the pattern, and transfer it to some nylon fabric. The outer profile was transferred and cut out with simple hand tools in a fashion that would allow the shape to be reconstructed as it was glued to a sole. It sounds simple, but it’s pretty fiddly work.

The latest running shoes use specialised rubber materials for the midsole. The solid foam wedge between the outer rubber and the inner sole cushions the foot. Those materials are only a few per cent ‘better’ than much more accessible foams that can be 3D printed. After sculpting a sole shape by hand using Blender, a friend 3D printed it. After that, the upper part was glued and ready for a test run. Which didn’t last long. It turned out that the lack of a stable heel counter (the bit around the back) that helps lock the heel in place meant the foot was too loose in the shoe, causing potential issues such as an ankle roll. That would be not good.  A follow-up session with a sports-focused chiropodist demonstrated that all this was rather pointless before the fundamental issues of strength and fitness were addressed. So, whilst it was fun to see an attempt to beat the big boys at their own game, it sure isn’t easy to pull it off, especially if you can’t get off the sofa.

The invention of flexible 3D printing filaments spurred the development of a wide range of 3D-printed footwear, like these low-poly beauties. While we’re 3D printing shoes, we also need some lace locks. Finally, with winter approaching for us Northerners, perhaps it’s time to run off a pair of 3D-printed strap-on cleats.

Thanks to [fluffy] for the tip!

[Christina Ernst] executed a fantastic idea just in time for Halloween: her very own Remy the rat (from the 2007 film Ratatouille). Just like in the film Remy perches on her head and appears to guide her movements by pulling on hair as though operating a marionette. It’s a great effect, and we love the hard headband used to anchor everything, which also offers a handy way to route the necessary wires.

Behind Remy are hidden two sub-micro servos, one for each arm. [Christina] simply ties locks of her hair to Remy’s hands, and lets the servos do the rest. Part of what makes the effect work so well is that Remy is eye-catching, and the relatively small movements of Remy’s hands are magnified and made more visible in the process of moving the locks of hair.

Originally Remy’s movements were random, but [Christina] added an MPU6050 accelerometer board to measure vertical movements of her own arm. She uses that sensor data to make Remy’s motions reflect her own. The MPU6050 is economical and easy to work with, readily available on breakout boards from countless overseas sellers, and we’ve seen it show up in all kinds of projects such as this tiny DIY drone and self-balancing cube.

Want to make your own Remy, or put your own spin on the idea? The 3D models and code are all on GitHub and if you want to see more of it in action, [Christina] posts videos of her work on TikTok and Instagram.

[via CBC]

Today, you likely often authenticate or pay for things with a tap, either using a chip in your card, or with your phone, or maybe even with your watch or a Yubikey. Now, imagine doing all these things way back in 1998 with a single wearable device that you could shower or swim with. Sound crazy?

These types of transactions and authentications were more than possible then. In fact, the Java ring and its iButton brethren were poised to take over all kinds of informational handshakes, from unlocking doors and computers to paying for things, sharing medical records, making coffee according to preference, and much more. So, what happened?

Just Press the Blue Dot

Perhaps the most late-nineties piece of tech jewelry ever produced, the Java Ring is a wearable computer. It contains a tiny microprocessor with a million transistors that has a built-in Java Virtual Machine (JVM), non-volatile storage, and an serial interface for data transfer.

While it might be the coolest piece in the catalog, the Java ring was just one of many ways to get your iButton. But wait, what is this iButton I keep talking about?

In 1989, Dallas Semiconductor created a storage device that resembles a coin cell battery and uses the 1-Wire communication protocol. The top of the iButton is the positive contact, and the casing acts as ground. These things are still around, and have many applications from holding bus fare in Istanbul to the immunization records of Canadian cows.

For $15 in 1998 money, you could get a Blue Dot receptor to go with it for sexy hardware two-factor authentication into your computer via serial or parallel port. Using an iButton was as easy as pressing the ring (or what have you) up against the Blue Dot.

Indestructible Inside and Out, Except for When You Need It

Made of of stainless steel and waterproof grommets, this thing is built to be indestructible. The batteries were rated for a ten-year life, and the ring itself for one million hot contacts with Blue Dot receptors.

This thing has several types of encryption going for it, including 1024-bit RSA public-key encryption, which acts like a PGP key. There’s a random number generator and a real-time clock to disallow backdating transactions. And the processor is driven by an unstabilized ring oscillator, so it constantly varies its clock speed between 10 and 20 MHz. This way, the speed can’t be detected externally.

But probably the coolest part is that the embedded RAM is tamper-proof. If tampered with, the RAM undergoes a process called rapid zeroization that erases everything. Of course, while Java Rings and other iButton devices maybe be internally and externally tamper-proof, they can be lost or stolen quite easily. This is part of why the iButton came in many form factors, from key chains and necklaces to rings and watch add-ons. You can see some in the brochure below that came with the ring:

The Part You’ve Been Waiting For

I seriously doubt I can get into this thing without totally destroying it, so these exploded views will have to do. Note the ESD suppressor.

So, What Happened?

I surmise that the demise of the Java Ring and other iButton devices has to do with barriers to entry for businesses — even though receptors may have been $15 each, it simply cost too much to adopt the technology. And although it was stylish to Java all the things at the time, well, you can see how that turned out.

If you want a Java Ring, they’re on ebay. If you want a modern version of the Java Ring, just dissolve a credit card and put the goodies in resin.

The Bigscreen Beyond is a small and lightweight VR headset that in part achieves its small size and weight by requiring custom fitting based on a facial scan. [Val’s Virtuals] managed to improve fitment even more by redesigning a facial interface and using a 3D scan of one’s own head to fine-tune the result even further. The new designs distribute weight more evenly while also providing an optional flip-up connection.

It may be true that only a minority of people own a Bigscreen Beyond headset, and even fewer of them are willing to DIY their own custom facial interface. But [Val]’s workflow and directions for using Blender to combine a 3D scan of one’s face with his redesigned parts to create a custom-fitted, foam-lined facial interface is good reading, and worth keeping in mind for anyone who designs wearables that could benefit from custom fitting. It’s all spelled out in the project’s documentation — look for the .txt file among the 3D models.

We’ve seen a variety of DIY approaches to VR hardware, from nearly scratch-built headsets to lens experiments, and one thing that’s clear is that better comfort is always an improvement. With newer iPhones able to do 3D scanning and 1:1 scale scanning in general becoming more accessible, we have a feeling we’re going to see more of this DIY approach to ultra-customization.

[Zibartas] recently created wearable helmets from the game Starfield that look fantastic, and we’re happy to see that he created a video showcasing the whole process of design, manufacture, and assembly. The video really highlights just how much good old-fashioned manual work like sanding goes into getting good results, even in an era where fancy modern equipment like 3D printing is available to just about anyone.

The visor, for example, is one such example. The usual approach to making a custom helmet visor (like for Daft Punk helmet builds) is some kind of thermoforming. However, the Starfield helmet visors were poor candidates due to their shape and color. [Zibartas]’s solution was to 3D print the whole visor in custom-tinted resin, followed by lots and lots of sanding and polishing to obtain a clear and glassy-smooth end product.

A lot of patient sanding ended up being necessary for other reasons as well. Each helmet has a staggering number of individual parts, most of which are 3D printed with resin, and these parts didn’t always fit together perfectly well.

[Zibartas] also ended up spending a lot of time troubleshooting an issue that many of us might have had an easier time recognizing and addressing. The helmet cleverly integrates a faux-neon style RGB LED strip for internal lighting, but the LED strip would glitch out when the ventilation fan was turned on. The solution after a lot of troubleshooting ended up being simple decoupling capacitors, helping to isolate the microcontrollers built into the LED strip from the inductive load of the motors.

What [Zibartas] may have lacked in the finer points of electronics, he certainly makes up for in practical experience when it comes to wearable pieces like these. The helmets look solid but are in fact full of open spaces and hollow, porous surfaces. This makes them more challenging to design and assemble, but it pays off in spades when worn. The helmets not only look great, but allow a huge amount of airflow. This along with the fans makes them comfortable to wear as well as prevents the face shield from misting up from the wearer’s breathing. It’s a real work of art, so check out the build video, embedded just below.