Printable Portable Mask Gives You The Numbers On Your Workout

January 16, 2022 by Dan Maloney 7 Comments

We’re currently in the midst of New Year’s Resolutions season, which means an abundance of spanking new treadmills and exercise bikes. And one thing becomes quickly obvious while using those machines: the instruments on them are, at best, only approximately useful for measuring things like your pulse rate, and in the case of estimating the calories burned by your workout, are sometimes wildly optimistic.

If precision quantification of your workout is your goal, you’ll need to monitor your “VO₂max”, a task for which this portable, printable mask is specifically designed. This is [Robert Werner]’s second stab at a design that senses both pressure differential and O₂ concentration to calculate the maximum rate of oxygen usage during exercise. This one uses a commercially available respirator, of the kind used for painting or pesticide application, as the foundation for the build. The respirator’s filter elements are removed from the inlets to provide free flow of air into the mask, while a 3D printed venturi tube is fitted to its exhaust port. The tube houses the pressure and O₂ sensors, as well as a LiPo battery pack and an ESP32. The microcontroller infers the volume of exhaled air from the pressure difference, measures its O₂ content, and calculates the VO₂ max, which is sent via Bluetooth to a smartphone running an exercise tracking app like Zwift or Strava.

[Robert] reports that his $100 instrument compares quite well to VO₂ max measurements taken with a $10,000 physiology lab setup, which is pretty impressive. The nice thing about the design of this mask is how portable it is, and how you can take your exercise routine out into the world — especially handy if your fancy exercise bike gets bricked.

Two views of the M19O2 oxygen concentrator

Design Improvements Make DIY Oxygen Concentrator Even Better

August 18, 2021 by Dan Maloney 8 Comments

A lot of projects we feature on these pages are of the “one and done” variety — tactical builds that serve a specific purpose with little need for further development. Some projects, though, come out as rough prototypes and then go through multiple rounds of refinement, a process we really enjoy tracking down and following. And when the project is something as important as an oxygen concentrator that can be built and maintained easily, all the better.

The need for cheap oxygen concentrators stems directly from the COVID-19 pandemic, which suggested that high-flow oxygen therapy was a better choice than invasive intubations and mechanical ventilation. But medical-grade oxygen isn’t always easy to come by in all parts of the world, so easily built oxygen concentrators, which rely on the nitrogen-adsorbing properties of the mineral zeolite, are meant to fill the gaps. Early versions of the M19O2 and the related OxyKit concentrator, had a very homebrew feel to them, built on wooden frames as they were. And while the rustic nature of the early builds didn’t detract from their utility, the hackers behind them, including our own [Anool Mahidharia], have been making incremental improvements aimed at not only making the devices work better, but also making them easier to build.

The hackers at Maker’s Asylum have done a fantastic job at documenting their work, with everything posted to a GitHub repo so that anyone can undertake a build. And really, for something as important as making oxygen when it’s needed, there’s really no reason not to give this a try.

Building An Oxygen Concentrator: It Isn’t Rocket Science

May 10, 2021 by Jenny List 40 Comments

Back at the start of the pandemic, a variety of hacker designs for life-saving machinery may have pushed the boundaries of patient safety. There are good reasons that a ventilator must pass extensive safety testing and certification before it can be attached to a patient, because were it to in some way fail, the patient would die. A year later, we have many much safer and more realistic ways to use our skills as part of the effort.

Probably one of the most ambitious projects comes from a coalition of Indian hackerspaces who are adapting a proven oxygen concentrator for local manufacture. Among them is Hackaday’s own [Anool Mahidharia], who hosts a Maker’s Asylum video (embedded below) explaining how the oxygen concentrator works and how they can be made safely.

The team have proven their ability in manufacturing over the past year, here showing off the M19 motorised air purifying respirator.

An oxygen concentrator is both surprisingly simple and imbued with a touch of magic. At its center are two columns of zeolite, a highly porous aluminosilicate mineral that performs the task of a molecular sieve. When air is pumped into the column, the zeolite traps nitrogen, leaving the oxygen-enriched remnant to be supplied onwards. There are two such columns to allow each to be on an alternate cycle of enrichment or purging to remove the accumulated nitrogen.

The point of the video is to show that such a device can be constructed from readily available parts and with common tools; as the title says it isn’t rocket science. Concentrators produced by the hackerspace coalition won’t save the world on their own, but as a part of the combined effort they can provide a useful and reliable source of oxygen that will make a significant difference in a country whose oxygen distribution network is under severe strain.

We previously covered the Indian oxygen concentrator effort when they launched the project. Their website can be found on the Maker’s Asylum website, and their crowdfunding campaign can be found on the Indian crowdfunding platform, Ketto. They have already proved their ability to coordinate large-scale manufacturing with their previous PPE and respirator projects, so please consider supporting them if you can. Meanwhile, we can’t help a twinge of space envy, from the fleeting glimpse of Maker’s Asylum in the video.

Continue reading “Building An Oxygen Concentrator: It Isn’t Rocket Science” →

Open-Source Oxygen Hack Chat

May 3, 2021 by Dan Maloney 20 Comments

Join us on Wednesday, May 5 at noon Pacific for the Open-Source Oxygen Hack Chat with Maher Daoudi and the OxiKit Team!

In such tumultuous times, it may be hard to remember last week, let alone last year. But if you dig back a bit, you may recall what a panic the world was in at this point in 2020 about the ventilator crisis. With COVID-19 cases on the rise and the potential for great numbers of patients needing intensive care, everyone and their brother was hacking together makeshift ventilators, in the well-intentioned belief that their inventions would help relieve the coming shortage of these lifesaving medical mechanical miracles.

As it came to pass, though, more COVID-19 patients have benefited from high-flow oxygen therapy than from mechanical ventilation. That’s great news in places where medical oxygen is cheap and easily available, but that’s always the case. We’ve seen recent reports of hospitals in India running out of oxygen, and even rural and remote areas of the developed world can find themselves caught without enough of the vital gas.

To meet the world’s increasing demand for high-flow oxygen therapy, the team at OxiKit has developed an open-source oxygen concentrator that can be built for far less than what commercial concentrators cost. By filtering the nitrogen out of the air, the concentrator provides oxygen at 90% or higher purity, at a flow of up to 25 liters per minute.

Oxikit founder Maher Daoudi and some of the technical team will join us for this Hack Chat to discuss the details of making oxygen concentrators. We’ll learn about how they work, what the design process for their current concentrator was like, and how they got past the obstacles and delivered on the promise of high-flow oxygen for the masses.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, May 5 at 12:00 PM Pacific time. If time zones have you tied up, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.
Continue reading “Open-Source Oxygen Hack Chat” →

A Simple But Effective High-Flow Oxygen Concentrator From Hardware Store Parts

March 24, 2021 by Dan Maloney 76 Comments

To say that a lot has happened in the year since the COVID-19 pandemic started is an understatement of epic proportions, so much so that it may be hard to remember how the hardware hacking community responded during those early days, with mass-produced PPE, homebrew ventilators and the like. But we don’t recall seeing too many attempts to build something like this DIY oxygen concentrator during that initial build-out phase.

Given the simplicity and efficacy of the design, dubbed OxiKit, it seems strange that we didn’t see more of these devices. OxiKit uses zeolite, a porous mineral that can be used as a molecular sieve. The tiny beads are packed into columns made from hardware store PVC pipes and fittings and connected to an oil-less air compressor through some solenoid-controlled pneumatic valves. After being cooled in a coil of copper pipe, the compressed air is forced through one zeolite column, which preferentially retains the nitrogen while letting the oxygen pass through. The oxygen stream is split, with part going into a buffer tank and part going into the outlet of the second zeolite column, where it forces the adsorbed nitrogen to be released. An Arduino controls the valves that alternate the gas flow back and forth, resulting in 15 liters per minute of 96% pure oxygen.

OxiKit isn’t optimized as a commercial oxygen concentrator is, so it’s not particularly quiet. But it’s a heck of a lot cheaper than a commercial unit, and an easy build for most hackers. OxiKit’s designs are all open source, but they do sell kits and some of the harder-to-source parts and supplies, like the zeolite. We’d be tempted to build something like this just because the technology is so neat; having a source of high-flow oxygen available isn’t a bad idea, either.

Got Oxygen? Future Mars Missions Are Relying On The MOXIE Of Perseverance

March 9, 2021 by Dan Maloney 31 Comments

The rule of thumb with planetary exploration so far has been, “What goes up, stays up.” With the exception of the Moon and a precious few sample return missions to asteroids and comets, once a spacecraft heads out, it’s never seen again, either permanently plying the void of interplanetary or interstellar space, or living out eternity on the surface of some planet, whether as a monument to the successful mission that got it there or the twisted wreckage of a good attempt.

At the risk of jinxing things, all signs point to us getting the trip to Mars reduced to practice, which makes a crewed mission to Mars something that can start turning from a dream to a plan. But despite what some hardcore Martian-wannabees say, pretty much everyone who goes to Mars is going to want to at least have the option of returning, and the logistical problems with that are legion. Chief among them will be the need for propellants to make the return trip. Lugging them from Earth would be difficult, to say the least, but if an instrument the size of a car battery that hitched a ride to Mars on Perseverance has anything to say about it, future astronauts might just be making their own propellants, literally pulling them out of thin air.

Continue reading “Got Oxygen? Future Mars Missions Are Relying On The MOXIE Of Perseverance” →

Be A Fire Bender With The Power Of Magnets

July 23, 2018 by Dan Maloney 26 Comments

More often than you think, scientific progress starts with a simple statement: “Huh, that’s funny…” That’s the sign that someone has noticed something peculiar, and that’s the raw fuel of science because it often takes the scientist down interesting rabbit holes that sometimes lead to insights into the way the world works.

[Ben Krasnow] ended up falling down one of those rabbit holes recently with his experiments with magnets and flames. It started with his look at the Zeeman effect, which is the observation that magnetic fields can influence the spectral lines of light emitted by certain sources. In a previous video, [Ben] showed that light from a sodium lamp could be dimmed by a powerful electromagnet. Some of his viewers took exception to his setup, which used an oxy-acetylene flame doped with sodium passing through the poles of the magnet; they thought the effect observed was a simple magnetohydrodynamic effect, and not the Zeeman effect he was supposed to be testing. That led to the experiments in the video below, which started with a candle flame being strongly deflected by the magnet. [Ben] methodically worked through the problem, eliminating variables by going so far as to blow soap bubbles of various gasses within the magnet’s poles to rule out the diamagnetism of oxygen as a cause of the phenomenon. He finally showed that even hot air by itself is deflected, using a simple light bulb and a FLIR camera. It’s good stuff, and well worth a watch.

Spoiler alert: [Ben] is still scratching his head about what’s going on, and we’re looking forward to his conclusions. This isn’t his first rabbit hole expedition, of course; his experiments with creating plasma with high-pressure water were fascinating, as were his DIY superconducting ceramics. Continue reading “Be A Fire Bender With The Power Of Magnets” →