2021: As The Hardware World Turns

January 3, 2022 by Tom Nardi 15 Comments

Well, that didn’t go quite as we expected, did it? Wind the clock back 365 days, and the world seemed to be breathing a collective sigh of relief after making it through 2020 in one piece. Folks started getting their COVID-19 vaccines, and in-person events started tentatively putting new dates on the calendar. After a rough year, it seemed like there was finally some light at the end of the tunnel.

Turns out, it was just a another train. New variants of everyone’s favorite acute respiratory syndrome have kept the pandemic rolling, and in many parts of the world, the last month or so has seen more new cases of the virus than at any point during 2020. This is the part of the Twilight Zone episode were we realize that not only have we not escaped the danger, we didn’t even understand the scope of it to begin with.

Case in point, the chip shortages. We can’t blame it entirely on the pandemic, but it certainly hasn’t helped matters. From video game systems to cars, production has crawled to a standstill as manufacturers fight to get their hands on integrated circuits that were once plentiful. It’s not just a problem for industry either, things have gotten so bad that there’s a good chance most of the people reading this have found themselves unable to get their hands on a part or two these last few months. If you were working on a hobby project, it’s a temporary annoyance. But for those who planned on finally bringing their latest big idea to market, we’ve heard tales of heartbreaking delays and costly redesigns.

It would be easy to look at the last twelve months and see nothing but disappointment, but that’s hardly the attitude you want to have at the beginning of the year. So let’s take the high road, and look back on some of the highlights from 2021 as we turn a hopeful eye towards the future.

Continue reading “2021: As The Hardware World Turns” →

flow chart for Assessment of the Feasibility of Using Noninvasive Wearable Biometric Monitoring Sensors to Detect Influenza and the Common Cold Before Symptom Onset paper

Wearables Can Detect The Flu? Well…Maybe…

December 12, 2021 by Orlando Hoilett 15 Comments

Surprisingly there are no pre-symptomatic screening methods for the common cold or the flu, allowing these viruses to spread unbeknownst to the infected. However, if we could detect when infected people will get sick even before they were showing symptoms, we could do a lot more to contain the flu or common cold and possibly save lives. Well, that’s what this group of researchers in this highly collaborative study set out to accomplish using data from wearable devices.

Participants of the study were given an E4 wristband, a research-grade wearable that measures heart rate, skin temperature, electrodermal activity, and movement. They then wore the E4 before and after inoculation of either influenza or rhinovirus. The researchers used 25 binary, random forest classification models to predict whether or not participants were infected based on the physiological data reported by the E4 sensor. Their results are pretty lengthy, so I’ll only highlight a few major discussion points. In one particular analysis, they found that at 36 hours after inoculation their model had an accuracy of 89% with a 100% sensitivity and a 67% specificity. Those aren’t exactly world-shaking numbers, but something the researchers thought was pretty promising nonetheless.

One major consideration for the accuracy of their model is the quality of the data reported by the wearable. Namely, if the data reported by the wearable isn’t reliable itself, no model derived from such data can be trustworthy either. We’ve discussed those points here at Hackaday before. Another major consideration is the lack of a control group. You definitely need to know if the model is simply tagging everyone as “infected” (which specificity does give us an idea of, to be fair) and a control group of participants who have not been inoculated with either virus would be one possible way to answer that question. Fortunately, the researchers admit this limitation of their work and we hope they will remedy this in future studies.

Studies like this are becoming increasingly common and the ongoing pandemic has motivated these physiological monitoring studies even further. It seems like wearables are here to stay as the academic research involving these devices seems to intensify each day. We’d love to see what kind of data could be obtained by a community-developed device, as we’ve seen some pretty impressive DIY biosensor projects over the years.

Respiratory rate measuring device attached to volunteer's abdomen along with automated antidote injection system

Researchers Use Wearable To Detect And Reverse Opioid Overdoses In Real-Time

December 4, 2021 by Orlando Hoilett 32 Comments

Opioid overdose-related deaths have unfortunately been increasing over the last few decades, with the COVID-19 pandemic exacerbating this public health crisis even further. As a result, many scientists, healthcare professionals, and government officials have been working tirelessly to end this deadly epidemic. Researchers at the University of Washington are one such group and have recently unveiled a wearable to both detect opioid overdose and deliver an antidote, in real-time, restoring normal bodily function.

As the researchers describe in their paper, opioid overdose causes respiratory rate depression which will lead to hypoxia (insufficient oxygen in the blood) and ultimately death. Fortunately, opioid overdose can be readily reversed using naloxone, a compound that binds to receptors in the brain, outcompeting the opiates themselves, and restoring normal breathing. Unfortunately, if someone is overdosing, they are unable to self-administer the antidote and with many opioid overdoses occurring when the victim is alone (51.8%), it is necessary to develop an automated system to deliver the antidote when an overdose is detected.

The researchers begin by describing their process for measuring respiration, of which there are several options. You could use photoplethysmography in much of the same way we measure heart rate. Or you could measure the changing impedance of the chest cavity during breathing or even use an intraoral sensor that measures airflow in the mouth. Instead, the researchers opt to measure respiration by attaching accelerometers to the patient’s abdomen and measuring the movement of the abdominal cavity during breathing. They admit their technique becomes problematic when the patient is not stationary, but argue that in the case of a drug overdose, the patient is likely to be immobilized and the device would be able to measure respiration with ease. They tested their device across dozens of healthy, human volunteers, and even some opiate users themselves, and showed their technique had good agreement with a reference respiratory belt placed around the volunteers’ chests.

The cool part about this paper is that they demonstrated a “closed-loop” feedback system in which their device measured respiration, detected cessation in breathing (indicating an overdose), and delivered the antidote. To deliver naloxone, they leveraged an existing, commercially-available drug delivery system that requires a user to manually activate the device by pressing a button. They hacked the device a bit such that the trigger could be actuated using a servo motor properly positioned to depress the button when an opioid overdose is detected. They simulated an overdose by asking the healthy, human volunteers to hold their breath for a period greater than 15 seconds. They were able to successfully deliver the antidote to 100% of their volunteer group, indicating the device could potentially work in real-world settings.

Now, the form factor of the device undoubtedly needs to improve in order to deploy this device into the field, but we imagine those are improvements are underway and patients have shown willingness to wear such devices already. Also, there’s still a bit of a question of whether or not accelerometer-based breathing detection is optimal since some drug overdoses cause seizures. Nevertheless, this is an important step in combating the alarming rise in opioid overdose-related deaths and we hope to see many more advances in patient monitoring technologies in this field.

Turning Old Masks Into 3D Printer Filament

October 19, 2021 by Tom Nardi 23 Comments

Disposable masks have been a necessity during the COVID-19 pandemic, but for all the good they’ve done, their disposal represents a monumental ecological challenge that has largely been ignored in favor of more immediate concerns. What exactly are we supposed to do with the hundreds of billions of masks that are used once or twice and then thrown away?

If the research being conducted at the University of Bristol’s Design and Manufacturing Futures Lab is any indication, at least some of those masks might get a second chance at life as a 3D printed object. Noting that the ubiquitous blue disposable mask is made up largely of polypropylene and not paper as most of us would assume, the team set out to determine if they could process the masks in such a way that they would end up with a filament that could be run through a standard 3D printer. While there’s still some fine tuning to be done, the results so far are exceptionally impressive; especially as it seems the technique is well within the means of the hobbyist.

The first step in the process, beyond removing the elastic ear straps and any metal strip that might be in the nose, is to heat a stack of masks between two pieces of non-stick paper with a conventional iron. This causes the masks to melt together, and turn into a solid mass that’s much easier to work with. These congealed masks were then put through a consumer-grade blender to produce the fine polypropylene granules that’re suitable for extrusion.

Mounted vertically, the open source Filastruder takes a hopper-full of polypropylene and extrudes it into a 1.75 mm filament. Or at least, that’s the idea. The team notes that the first test run of filament only had an average diameter of 1.5 mm, so they’re modifying the nozzle and developing a more powerful feed mechanism to get closer to the goal diameter. Even still, by cranking up the extrusion multiplier in the slicing software, the team was able to successfully print objects using the thin polypropylene filament.

This is only-during-a-pandemic recycling, and we’re very excited to see this concept developed further. The team notes that the extrusion temperature of 260 °C (500 °F) is far beyond what’s necessary to kill the COVID-19 virus, though if you planned on attempting this with used masks, we’d imagine they would need to be washed regardless. If the hacker and maker community were able to use their 3D printers to churn out personal protective equipment (PPE) in the early days of the pandemic, it seems only fitting that some of it could now be ground up and printed into something new.

Electronic Covid Test Tear Down Shows Frustrating Example Of 1-Time-Use Waste

October 17, 2021 by Al Williams 68 Comments

The latest video from [TheSignalPath] is a result of his purchase of a home COVID-19 test. He found an electronic version that connects to your cell phone and displays the results on the phone. The device is an antigen test and, internally, works like the home tests that show the results using lines similar to a pregnancy test. So, somehow, the phone version reads the lines and communicates with the phone. But how? That’s the point of the video, which you can see below.

In a traditional test, there’s a control line that has to appear to show that the test was done correctly. Then a line under that indicates detection of the virus. The circuit board inside the electronic test has a plastic unit onboard that contains a similar strip and has optical sensors for both the reference line and the detection line. Since it is essentially an optical device — there are some lenses in the strip assembly that look like they are detecting the dye as it moves through the strip with LEDs onboard to shed light on the situation.

Under the microscope, the CPU is a typical Bluetooth-capable ARM chip from Nordic. The board did power up, but the device is made to only operate once because of the test strip. The video notes — and we agree — it seems wasteful to create an entire Bluetooth-enabled microcontroller board with optical components just to read a strip one time that is pretty easy to read to start with. We’ll stick with the simple test strip. Still, it is interesting to see the insides.

If you want to read more about antigen tests, we covered that. We also talked about PCR testing.

Continue reading “Electronic Covid Test Tear Down Shows Frustrating Example Of 1-Time-Use Waste” →

A Raspberry Pi-based COVID Green Pass validator verifies a QR code on a phone.

COVID Green Pass Validator With Raspberry Pi

September 25, 2021 by Kristina Panos No comments

It seems like every nation is dealing with the plague a little differently. In June, the EU instated a COVID Green Pass which comes in the form of a paper or digital QR code. It was designed to grease the wheels of travel throughout Europe and allow access to nursing homes. As of early August, the Green Pass is now required of those 12 and older in Italy to gain access to bars and restaurants, museums, theaters, etc. — anywhere people gather in sizeable groups. The Green Pass shows that you’ve either been vaccinated, have had COVID and recovered, or you have tested negative, and there are different half-lives for each condition: nine months for vaccinated, six for recovered, and just forty-eight hours for a negative test.

[Luca Dentella] has built a Green Pass validator using a Raspberry Pi and a Raspi camera. Actual validation must be done through the official app, so this project is merely for educational purposes. Here’s how it works: the user data including their status and the date/time of pass issuance are encoded into a JSON file, then into CBOR, then it is digitally signed for authenticity. After that, the information is zipped up into a base-45 string, which gets represented as a QR code on your phone. Fortunately, [Luca] found the Minister of Health’s GitHub, which does the hard work of re-inflating the JSON object.

[Luca]’s Pi camera reads in the QR and does complete validation using two apps — a camera client written in Python that finds QRs and sends them to the validation server, written in Node.js. The validation server does formal verification including verifying the signature and the business rules (e.g. has it been more than 48 hours since Karen tested negative?) Fail any of these and the red LED lights up; pass them all and you get the green light. Demo video is after the break.

Are you Canadian? Then check this out, eh?

Continue reading “COVID Green Pass Validator With Raspberry Pi” →

Monoclonal Antibodies: The Guided Missiles Of Medicine

September 15, 2021 by Dan Maloney 11 Comments

Whenever anyone mentions the word “antibodies” these days, it’s sure to grab your attention. Thoughts generally flow to the human immune system and the role it plays in the ongoing COVID-19 pandemic, and to how our bodies fight off disease in general. The immune system is complex in the extreme, but pretty much everyone knows that antibodies are part of it and that they’re vital to the ability of the body to recognize and neutralize invaders like bacteria and viruses.

But as important as antibodies are to long-term immunity and the avoidance of disease, that’s far from all they’re good for. The incredible specificity of antibodies to their target antigens makes them powerful tools for biological research and clinical diagnostics, like rapid COVID-19 testing. The specificity of antibodies has also opened up therapeutic modalities that were once the stuff of science-fiction, where custom-built antibodies act like a guided missile to directly attack not only a specific protein in the body, but sometimes even a specific part of a protein.

Making these therapies work, though, requires special antibodies: monoclonal antibodies. These are very much in the news recently, not only as a possible treatment for COVID-19 but also to treat everything from rheumatoid arthritis to the very worst forms of cancer. But what exactly are monoclonal antibodies, how are they made, and how do they work?

Continue reading “Monoclonal Antibodies: The Guided Missiles Of Medicine” →