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?

We’ve all heard stories of the dangers of 3D printing, with fires from runaway hot ends or dodgy heated build plates being the main hazards. But what about the particulates? Can they actually cause health problems in the long run? Maybe, if new research into the carcinogenicity of common 3D printing plastics pans out.

According to authors [CheolHong Lim] and [DongSeok Seo], the research covered in this paper was undertaken because of reports of rare cancers among Korean STEM teachers, particularly those who used 3D printers in their curricula. It was thought that only long-term, continued exposure to the particulates generated by 3D printers could potentially be hazardous and that PLA was less likely to be hazardous than ABS. The study was designed to assess the potential carcinogenicity of both ABS and PLA particulates under conditions similar to what could be expected in an educational setting.

To do this, they generated particulates by heating ABS and PLA to extruder temperatures, collected and characterized them electrostatically, and dissolved them in the solvent DMSO. They used a cell line known as Balb/c, derived from fibroblasts of an albino laboratory mouse, to assess the cytotoxic concentration of each plastic, then conducted a comet assay, which uses cell shape as a proxy for DNA damage; damaged cells often take on a characteristically tailed shape that resembles a comet. This showed no significant DNA damage for either plastic.

But just because a substance doesn’t cause DNA damage doesn’t mean it can’t mess with the cell’s working in other ways. To assess this, they performed a series of cell transformation assays, which look for morphological changes as a result of treatment with a potential carcinogen. Neither ABS nor PLA were found to be carcinogenic in this assay. They also looked at the RNA of the treated cells, to assess the expression of genes related to carcinogenic pathways. They found that of 147 cancer-related genes, 113 were either turned up or turned down relative to controls. Finally, they looked at glucose metabolism as a proxy for the metabolic changes a malignant cell generally experiences, finding that both plastics increased metabolism in vitro.

Does this mean that 3D printing causes cancer? No, not by a long shot. But, it’s clear that under lab conditions, exposure to either PLA or ABS particulates seems to be related to some of the cell changes associated with carcinogenesis. What exactly this means in the real world remains to be seen, but the work described here at least sets the stage for further examination.

What does this all mean to the home gamer? For now, maybe you should at least crack a window while you’re printing.

If you’re feeling underwhelmed by yet another smartwatch announcement, then researchers at the University of Maryland may have just the wearable for you. Instead of just tracking your movement from one spot, Calico winds around you like a cartoon sidekick.

Using a “railway system,”(PDF) the Calico can travel around a garment to get better telemetry than if it were shackled to a wrist. By moving around the body, the robot can track exercise, teach dance moves, or take up-close heart measurements. Tracks can be magnetically linked across garments, and Calico can use different movement patterns to communicate information to the user.

This two-wheeled robot that rides the rails is built around a custom PCB with a MDBT42Q microcontroller for a brain which lets it communicate with a smartphone over Bluetooth Low Energy. Location is monitored by small magnets embedded in the silicone and plastic living hinge track, and it can use location as a way to provide “ambient visual feedback.”

The researchers even designed a friendly cover for the robot with googly eyes so that the device feels more personable. We think animated wearables could really take off since everyone loves cute animal companions, assuming they don’t fall into the uncanny valley.

If you love unusual wearables as much as we do, be sure to check out Wearable Sensors on Your Skin and the Wearable Cone of Silence.

They say that sitting is the new smoking. They’re wrong — smoking is much, much worse, for you than sitting, and smoking only while standing or while jogging around the block in no way to justify the habit. But they’re also not wrong that humans weren’t made for extended periods parked on their posteriors, but we do it anyway, to the detriment of our heart health, posture, and general well-being. So something like this butt-detecting stand-up reminder could make a big difference to your health.

While like many of us, [Dave Bennett] has a wearable that prompts him to get up and move around after detecting 30 minutes of sitting, he found that it’s too easy to dismiss the alarm and just go right on sitting. Feeling like he needed a little more encouragement to get up and go, he built a presence detector completely from scratch. His sensor is a sheet of static-protective Velostat foam wrapped in conductive tape; when compressed, the resistance across the pad drops, making it easy to detect with a simple comparator circuit.

We admit to getting excited when we first saw the alarm circuit; a quick glance at the schematic seemed like it was based on a 555, which it totally could be. But no, [Dave]’s design goals include protection against spoofing the alarm with a quick “cheek sneak,” which was most easily implemented in code. So that 8-pin device in the circuit is an ATtiny85, which sounds the alarm after 30 minutes and requires him to stay off his butt for a full minute before resetting. The video below hits the high points of design and shows it in use.

Annoying? Yes, but that’s the point. Of course a standing desk would do the same thing, but that’s not going to work for everyone, so this is a nice alternative.

More bad news from Mars this week, and this time not just from Perseverance. Last week the eagerly anticipated first flight of the helicopter Ingenuity was delayed for a couple of days after failing a full-speed spin-up test of its rotors. That appears to have been a bigger deal than initially thought, as it required a significant rewrite of the helicopter’s software. That meant testing, of course, and subsequent upload to the UAV, which at 174 million miles away takes a bit of doing. The good news is that they were able to complete the full-speed rotor test without the full program upload, so we’re one step closer to flight, which may take place as early as Monday morning.

Meanwhile, over at Elysium Planitia, the Mars InSight lander has troubles of its own. The geophysical laboratory, which has been trying to explore the inner structure of Mars since landing in 2018, entered an “emergency hibernation” state this week because of a lack of sufficient power generation. Unlike the radioisotope-powered Perseverance rover, InSight relies on a pair of solar panels for its electricity, and those panels are being obscured by Martian dust. The panels normally get blown clean by Martian winds, but things have been calm lately and the dust has really built up. If this seems like deja vu all over again, it’s probably because a planet-wide dust storm is what killed the plucky Opportunity rover back in 2018. Here’s hoping the wind picks up a little and InSight can get back to work.

Funny what crops up in one’s newsfeed, especially when one is responsible for putting out content that populates others’ newsfeeds. We recently took a look at the dangers of “zinc fever”, a flu-like illness that can crop up after inhaling gasses produced by molten zinc. That resulted in stumbling across an article from last year about mild steel welding fumes being classified as a human carcinogen. This comes from the Health and Safety Executive, a UK government agency concerned with workplace health issues. The release is an interesting read, and it suggests that mild steel fumes can cause not only lung cancer but kidney cancer. The announcement is mainly concerned with British workplaces, of course, but there are some interesting tidbits in there, such as the fact that welding fumes make dust particles so small that they can reach down into the very lowest reaches of lungs, the alveoli where gas exchange occurs. It’s enough to make one invest in PAPR or some kind of fume extractor.

For those of a certain vintage, our first computer was probably something that bore little resemblance to a PC or laptop. It was likely a single-board affair or something like a C64, and acquiring the essential bit of hardware usually left little in the budget for a proper monitor. Little 12″ B&W TVs were a dime a dozen, though, and easily — if grainily — enlisted into service as a monitor by way of an RF modulator. To recreate a little of that magic with modern hardware, Hackaday contributor Adam Zeloof came up with the PiMod Zero, an RF-modulator hat for the Raspberry Pi Zero that turns the component video into an NTSC analog signal. He’s open-sourced the design files, or there’s a CrowdSupply campaign for those who prefer to buy.

And finally, if you somehow traveled back in time to the 1940s with a laptop, how long would it have taken you to crack the Enigma code? Longer than you think, at least according to Dr. Mike Pound over at Computerphile, who released a fascinating video on how Enigma worked and what it took for Turing and the gang at Bletchley to crack the code. We knew some of the details of Enigma’s workings before seeing this video, but Mike’s explanation was really good. And, his explanation of the shortcut method he used to decode an Enigma message made the whole process clearer to us than it’s ever been. Interesting stuff.

As more and more people spend their working hours behind a computer, bad posture and the accompanying back pain and back problems become a growing epidemic. To combat this in his own daily life, [ImageryEel] made PosturePack, a wearable Bluetooth-enabled posture sensor.

The PosturePack is designed to fit into a small pocket sewn into the pack of an undershirt, between the shoulder blades. It consists of a custom PCB with an ATmega32U4, BNO055 IMU, Bluetooth module,  small LiPo and power circuitry. Based on the orientation data from the IMU, a notification is sent over Bluetooth to a smartphone whenever the user hunches forward.

[ImageryEel] says although the mobile notifications worked, haptic feedback integrated into the unit would be a better option. This could also be used to remind the user to stand up and take a break now and then, and provide an alternative to a smartwatch for activity monitoring without sending every movement to someone else’s servers. Software will always be the hardest part for projects like these, especially as the device become “smarter”. Learning to recognize activity and postures is actually a good place for tiny machine learning models.

Compared The posture sensors we covered before had to be installed and set up at a specific workstation, like an ultrasound-based version attached to a chair, and a webcam-based version.

As we’ve looked at the subject of face masks in the first two parts of this series, our emphasis has been on a physical step to aid your chances of making it through the COVID-19 pandemic in one piece. But given that the upheaval caused by all the social changes enacted to protect the population are likely to leave an indelible mark on those who live through them, there are significant aspects of surviving all this that go beyond the physical.

This will be a once-in-a-lifetime event for many people, a significant number will find it traumatic in some way, and for many of those people there will be an immediate and then ongoing effect on mental health. If anyone is in doubt as to from what position this is coming, I count myself among that number.

The Pressure Of A Once In A Lifetime Event

Different countries have placed their own public health restrictions on their populations, but it’s likely that many of you are in some form of lockdown situation, with social or communal  activities and locations closed or curtailed, going out restricted, and with all around you in the same situation. A perfect storm of having social outlets removed while simultaneously being stuck at home perhaps with family or housemates you’d prefer not to spend too much time with is not ideal. Add to that the multiple stresses from the pandemic itself as well as other news stories from our turbulent world, and it’s hardly a surprising that it’s taking a toll.

In my case, I found myself abruptly deprived of my main social outlets, as my hackerspace closed for the duration and my group of friends could no longer hang out. Living in the depths of the countryside as I do can be great in normal times, but being forbidden to leave my little part of it and seeing nobody else at all except my family members for a couple of months has given me a rough ride.

At first I dove into online meetings, and quickly amassed a pile of new apps for different services on my phone. But then the sheer number of social groups came to take up most of my evenings, I found I had little left to say, and gained a new source of stress lest I’d said the wrong thing, or not supported someone adequately, or looked like a fool. I’ve had an up-and-down existence these last couple of months, and the same worries can be found in whether I can find enough Hackaday stories to make up a month, or whether I taxed my car on time.

It’s OK, This Isn’t Normal

It’s crazy, finding oneself approaching burn-out when one should be having an easier time of it due to less of life’s normal stresses. But I suspect I’m not alone in this. I think my mistake was to expect that in extraordinary times I could continue on as normal, because while the world around us has gone a little crazy it’s all the same in my little office with its gently humming PC and oversized clacky keyboard.

If I have a takeaway from all this, it’s that what I needed to do was to recognise that this isn’t normal. It’s unreasonable to expect to be able to do things as before, even to be able to do more than before. I wasn’t having endless Jitsi and Zoom meetings before all this, in fact I didn’t even have either service. So why was I suddenly deeming myself able to be the life and soul of the party 24-7, and then chastising myself for being unable to live up to it?

And why was I surprised that feeding the ever-hungry maw of a continuous daily publication such as Hackaday was feeling so daunting? Few of us can be superhuman at the best of times, so perhaps we should all recognise that it’s OK to back off a little when things become too much. I found that backing away from the interactions helped me a load, and spreading out my Hackaday work also made it less intimidating.

Recognising my limits and cutting back on the things that were bringing me down may have restored some balance, but I am still cut off from my peers and in uncomfortable proximity to my family. In this I am indebted to a small network of friends with whom I’ve been in regular phone contact. Not Jitsi or Zoom, good old-fashioned phone. We talk, we help, we keep each other sane. I hope I have been as much help to them in this as they have to me.

Finally, The Rest Of You Have  A Part To Play Too

This has been my attempt to make sense of the pandemic as a mental health event, drawing on my own experiences. I’m not out of the wood yet, but I hope if you find yourself in a similar state then some of my coping strategies may be of help to you.

There is another side to this though, and it lies with those of you who aren’t suffering particularly from all this. Wow, I envy you! Some of you though maybe won’t realise that not everyone is like you, so now’s the time to consider this, and think before you speak and act around other people during this difficult time. If our community has an ugly side at times it can be that its culture can be unforgiving, and sometimes what may seem like a throwaway comment on a forum or social media to you could have a crushing effect on someone else. Part of us all getting through is making much more of an effort to be nice to one another, and thereby making ourselves a little better. Let’s do that.

Take care, and think about what you post, and if you see someone you know abruptly disappear, check up on them. Together, we will get through all this.