The BiVACOR Total Artificial Heart: A Maglev Bridge To Life

July 28, 2024 by Maya Posch 28 Comments

The BiVACOR THA hooked up with the CTO Dianiel Timms in the background. (Credit: BiVACOR)

Outside of the brain, the heart is probably the organ that you miss the most when it ceases to function correctly. Unfortunately, as we cannot grow custom replacement hearts yet, we have to keep heart patients alive long enough for them to receive a donor heart. Yet despite the heart being essentially a blood pump, engineering even a short-term artificial replacement has been a struggle for many decades. A new contender has now arrived in the BiVACOR TAH (total artificial heart), which just had the first prototype implanted in a human patient.

Unlike the typical membrane-based pumps, the BiVACOR TAH is a rotary pump that uses an impeller-based design with magnetic levitation replacing bearings and theoretically minimizing damage to the blood. This design should also mean a significant flowrate, enough even for an exercising adult. Naturally, this TAH is only being tested as a bridge-to-transplant solution, for patients with a failing heart who do not qualify for a ventricular assist device. This may give more heart patients a chance to that donor heart transplant, even if a TAH as a destination therapy could save so many more lives.

The harsh reality is that the number of donor hearts decreases each year while demand increases, leading to unconventional approaches like xenotransplantation using specially bred pigs as donor, as well as therapeutic cloning to grow a new heart from the patient’s own cells. Having a universal TAH that could be left in-place (destination therapy) for decades would offer a solid option next to the latter, but remains elusive. As shown by e.g. the lack of progress with a TAH like the ReinHeart despite a promising 2014 paper in a bovine model.

Hopefully before long we’ll figure out a reliable way to fix this ‘just a blood pump’ in our bodies, regardless of whether it’s a biological or mechanical solution.

You’ve Got The Portable Radio, Now What About The Antenna?

July 28, 2024 by Jenny List 10 Comments

There’s an old saying in the amateur radio community that when it comes to antennas all you need is a piece of wet string. This may be a little fanciful, but it’s certainly true that an effective antenna can be made with surprisingly little in the way of conductor. It’s something [Evan Pratten VZ3ZZA] demonstrates amply with a description of the antenna he took camping in a Canadian provincial park.

Most of us would try some form of dipole on our adventures, but the antenna he’s using caught our eye as it’s described as an end-fed half-wave, but it has both a half-wave and quarter-wave element. Made from speaker cable or in this case thin mains cable for lamps, it’s obviously far from a perfect match and requires an ATU, but it generates an impressive array of FT4 contacts on a pretty meagre power level. We particularly like his in-plain-sight test run in the parking lot of a supermarket.

We frequently talk about the diversity of pursuits in amateur radio aside from that of the chequebook ham, and this project shows one of those. The world of QRP, operating at extreme low power, is not expensive to enter and can be extremely rewarding.

Hackaday Links: July 28, 2024

July 28, 2024 by Dan Maloney 14 Comments

What is this dystopia coming to when one of the world’s largest tech companies can’t find a way to sufficiently monetize a nearly endless stream of personal data coming from its army of high-tech privacy-invading robots? To the surprise of almost nobody, Amazon is rolling out a paid tier to their Alexa service in an attempt to backfill the $25 billion hole the smart devices helped dig over the last few years. The business model was supposed to be simple: insinuate an always-on listening device into customers’ lives to make it as easy as possible for them to instantly gratify their need for the widgets and whatsits that Amazon is uniquely poised to deliver, collecting as much metadata along the way as possible; multiple revenue streams — what could go wrong? Apparently a lot, because the only thing people didn’t do with Alexa was order stuff. Now Amazon is reportedly seeking an additional $10 a month for the improved AI version of Alexa, which will be on top of the ever-expanding Amazon Prime membership fee, currently at an eye-watering $139 per year. Whether customers bite or not remains to be seen, but we think there might be a glut of Echo devices on the second-hand market in the near future. We hate to say we told you so, but — ah, who are we kidding? We love to say we told you so.

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An RC Tracked Robot, Without The Pain

July 28, 2024 by Jenny List 13 Comments

Small robots can be found at all levels from STEM toys for kids all the way through to complex hacker projects. Somewhere along that line between easy enough for anyone to build and interesting enough for hackers lies the PlayCar, from [ComfySpace]. It’s a small build-it-yourself tracked robot that’s controlled from your smartphone via an app.

At the PlayCar’s heart is a Raspberry Pi Zero 2W, and surrounding it are a set of inexpensive off the shelf modules for power and motor control. The juice meanwhile comes from a set of AA batteries, and the motors are geared DC units. Having acquired all the components, the 3D printable parts can then be downloaded from Printables, and the ComfySpace app can be downloaded for either Apple or Android platforms.

It’s clear that ComfySpace is a start-up targeting the education sector, and we wish them every success. The approach of making an open platform is one we like, as it has the potential to create a community feeding back designs and add-ons rather than remaining proprietary. You can take a look at the video below the break for more information.

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A Demo Party On A Chip

July 28, 2024 by Jenny List 5 Comments

The demoscene has provided our community with its artistic outlet since the first computers which could handle graphics, and has stayed at the forefront of technology all the way. For all that though, there’s a frontier it hasn’t yet entirely conquered, which exists in the realm of silicon. To address this cones the ever awesome Tiny Tapeout, who are bringing their ASIC-for-the-masses scheme to the world of demos with an ASIC demo competition.

With a closing date of 6th of September, all accepted entrants get a free Tiny Tapeout tile for their entry. Entries are limited to two tiles or less. with VGA and audio outputs via a specified PMOD pinout. There are a variety of categories including the expected best sound and best graphics, but among them we’re most interested by the mixed signal one that includes analogue circuitry.

Tiny Tapeout has been a particularly exciting project over the last couple of years, truly breaking new ground for the hardware hacker world. Since they’ve just recently been able to start doing some analog design on the chips, we’re excited to see what people come up with for this competition, and we hope it will provide significant advancement to the art. In the best tradition of the demo scene, they’ve even made an intro for the competition, which you can see below the break.

Want to know what all the fuss is about? Start here!

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Printed Portable Computer Inspired By The Classics

July 28, 2024 by Tom Nardi 3 Comments

These days, laptop computers are all more or less the same, at least externally. Some are thicker than others, they might come in different colors, or with a 360° hinge that lets you flip the screen around the back and use it as a tablet, but overall they’ve all got the same shape and proportions. The industry, and indeed the users, eventually agreed on the best way to make a computer portable and are now fully committed to it.

But that wasn’t always the case. In the 1980s there were a number of laptops from the likes of Toshiba, Tandy, and even IBM that took a slightly different approach to the clamshell design. These computers featured ultra-wide displays with a hinge located closer to the center of the computer, giving the machine a distinctive “trunk” in the back. It’s these classic machines that clearly inspired [Michael Mayer] to design the Portable Pi 84.

[Michael] says that the 3D printed enclosure was largely designed around the 40% ortholinear keyboard, which itself is based on the Happy-Keyboard from [Luis Alegría]. The rest apparently just fell into place, such as the fact that the 1600 x 600 Waveshare 9.3 inch display happens to be almost the perfect size to cover the keyboard below it.

Compared to many of the other custom computer builds we’ve covered, the rear compartment of the Portable Pi 84 provides ample free space for the various system components. That includes the Raspberry Pi 4 that runs the show, a UPS “hat” that powers the system via a pair of 21700 batteries, and even a set of amplified speakers. It looks like there’s still plenty of room in the back for additional gear, such as an RTL-SDR or perhaps even a cartridge slot.

A particularly nice feature of this build are the inset panels on the rear of the machine, which allow for the various ports and connectors to be reconfigured by the user without having to re-print the entire case — one could imagine a replacement panel that features a connector for an external WiFi antenna, for example. We also like the use of heat-set inserts throughout the case, which will not only make the build sturdier, but means the case can be opened and closed regularly without fear of stripping out the screw holes.

So is this a computer or a cyberdeck? It’s hard to say. We tend to think that a proper deck needs to have a more unique physical layout, and technically this form factor was actually fairly popular at one point. But whatever you want to call builds like this, we’re stoked to see them become more common and better documented. Long live the truly personal computer.

French acrobatic artist [Bastien Dausse] flies around on an impressive anti-gravity device he created.

Low-Gravity Playground Looks Highly Entertaining (and Useful)

July 28, 2024 by Kristina Panos 22 Comments

With US astronauts scheduled to return to the Moon in 2026, it might be nice for them to really and truly know ahead of time what the gravity situation is going to be like. At 1/6th Earth’s gravity, the difference can be difficult to simulate.

But not anymore. French acrobatic artist [Bastien Dausse] has created a contraption that does exactly that. [Dausse] straps himself in, and is instantly able to slowly sproing about, up and down and all around in semi-slow motion, using this device which is calibrated to the Moon’s gravity. [Dausse]’s troupe’s performances center on the idea of gravity and of subverting it.

In order to achieve this effect, the swooping sculpture uses a pair of large counterweights. Check out the video below to see how they too become part of the action during a captivating duet performance. Although not attached, part of the device is a disk on which it smoothly moves around. It looks really fun, and more than a little bit dangerous. But mostly fun.

Did you know that Da Vinci created several experiments dedicated to determining the properties of gravity?

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