We are accustomed to medical devices being expensive, but sometimes the costs seem to far exceed reasonable expectations. At its most simplistic, a hearing aid should just be a battery, microphone, amplifier, and speaker, all wrapped in an enclosure, right? These kinds of parts can be had for a few dimes, so why do modern hearing aids cost thousands of dollars, and why can’t they seem to go down in price?
Continue reading “It Costs WHAT?! A Sounding Into Hearing Aids”
Join us on Wednesday, February 3 at noon Pacific for the Mechanical Timekeeping Hack Chat with Clickspring!
The reckoning of the passage of time has been of vital importance to humans pretty much for all our history, but for most of that time we were stuck looking at the movements of heavenly bodies or noting the changing of the seasons to answer questions of time. The search for mechanical aids to mark the passage of time began surprisingly early, though, pretty much from the time our ancestors first learned to work with metals.
Timekeeping devices were often created to please a potentate or to satisfy a religious imperative, but whatever the reason for their invention, these early clocks and calendars were key to a ton of discoveries. Timekeeping devices were among the first precision mechanisms, and as such formed the basis of much of our mechanical world. A mechanical representation of the passage of time also gave us some of the first precise observations of the physical world, which led to an enormous number of discoveries about the nature of the universe, not to mention practical skills such as navigation, which allowed us to explore the world with greater confidence.
In our era, precision timekeeping has moved beyond the mechanical realm into the subatomic world, and mechanisms built to please a prince are relegated to museums and collectors. That’s not to say there isn’t plenty to learn from the building of mechanical timepieces, as anyone who has watched any of the videos on Clickspring’s YouTube channel can attest. Clickspring not only makes some magnificent modern timepieces, like his famous open-frame clock, but recently he’s also branched out into the timekeeping mechanisms of the ancients. He built a reproduction Byzantine sundial-calendar, and tackled a reproduction of the famous Antikythera mechanism. The latter was undertaken using only the tools and materials that would have been available to the original maker. That led to an unexpected discovery and a detour into the world of scholarly publishing.
Clickspring has been busy lately, but he made some time to stop by the Hack Chat and talk about mechanical timepieces. We’ll talk about his modern builds, his forays into the mechanisms of antiquity, and his serendipitous discovery. On the way we’re likely to talk about what it takes to build precision mechanisms in a small shop, and whatever else that crops up.
Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, February 3 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 “Mechanical Timekeeping Hack Chat With Clickspring”
It’s easy to imagine that once a spacecraft leaves Earth’s atmosphere and is in a stable orbit, the most dangerous phase of the mission is over. After all, that’s when we collectively close the live stream and turn our attentions back to terrestrial matters. Once the fire and fury of the launch is over with, all the excitement is done. From that point on, it’s just years of silently sailing through the vacuum of space. What’s the worst that could happen?
Unfortunately, satellite radio provider Sirius XM just received a harsh reminder that there’s still plenty that can go wrong after you’ve slipped Earth’s surly bonds. Despite a flawless launch in early December 2020 on a SpaceX Falcon 9 and a reportedly uneventful trip to its designated position in geostationary orbit approximately 35,786 km (22,236 mi) above the planet, their brand new SXM-7 broadcasting satellite appears to be in serious trouble.
Maxar Technologies, prime contractor for the SXM-7, says they’re currently trying to determine what’s gone wrong with the 7,000 kilogram satellite. In a statement, the Colorado-based aerospace company claimed they were focused on “safely completing the commissioning of the satellite and optimizing its performance.” But the language used by Sirius XM in their January 27th filing with the U.S. Securities and Exchange Commission was notably more pessimistic. No mention is made of bringing SXM-7 online, and instead, the company makes it clear that their existing fleet of satellites will be able to maintain service to their customers until a replacement can be launched.
So what happened, and more importantly, is there any hope for SXM-7? Neither company has released any concrete details, and given the amount of money on the line, there’s a good chance the public won’t get the full story for some time. But we can theorize a bit based on what we do know, and make some predictions about where things go from here.
We are extraordinarily fortunate to live at a time in which hardware with astounding capabilities can be had for only a few dollars. Systems that would once have taken an expensive pile of chips and discretes along with months of development time to assemble are now integrated onto commodity silicon. Whether it is a Linux-capable system-on-chip or a microcontroller, such peripherals as WiFi, GPUs, Bluetooth, or USB stacks now come as part of the chip, just another software library rather than a ton of extra hardware.
If there is a price to be paid for this convenience, it comes in the form of the blob. A piece of pre-compiled binary software that does the hard work of talking to the hardware and which presents a unified API to the software. Whether you’re talking to the ESP32 WiFi through an Arduino library or booting a Raspberry Pi with a Linux distribution, while your code may be available or even maybe open source, the blob it relies upon to work is closed source and proprietary. This presents a challenge not only to Software Libre enthusiasts in search of a truly open source computer, but also to the rest of us because we are left reliant upon the willingness of the hardware manufacturer to update and patch their blobs.
An open-source advocate would say that the solution is easy, the manufacturers should simply make their blobs open-source. And it’s true, were all blobs open-source then the Software Libre crowd would be happy and their open-source nature would ease the generation of those updates and patches. So why don’t manufacturers release their blobs as open-source? In some cases that may well be due to a closed-source mindset of never releasing anything to the world to protect company intellectual property, but to leave it at that is not a full answer. To fully understand why that is the case it’s worth looking at how our multifunctional chips are made.
Continue reading “Why Blobs Are Important, And Why You Should Care”
Hackaday editors Mike Szczys and Elliot Williams discuss the greatest hacks of the week that was. Antennas aren’t rocket science, so this week we really enjoyed a video that demystifies antenna designs and a project that tunes up the antennas on cheap wireless modules in the simplest of ways. Google’s in the news this week with the end to project Loon, and a dust-up with the volunteer package maintainers who have spent years making sure Chromium browser is in the Linux repos. Elliot is gaga for magic eye tubes and crazy musical instruments, while Mike is over the moon for a chain-based clock display. We close up the episode talking about the Concorde, and the math behind cable mechanisms.
Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!
Direct download (~65 MB)
Sudo is super important Linux utility, as well as the source of endless jokes. What’s not a joke is CVE-2021-3156, a serious vulnerability around incorrect handling of escape characters. This bug was discovered by researchers at Qualys, and has been in the sudo codebase since 2011. If you haven’t updated your Linux machine in a couple days, you may very well be running the vulnerable sudo binary still. There’s a simple one-liner to test for the vulnerability:
sudoedit -s '\' `perl -e 'print "A" x 65536'`
In response to this command, my machine throws this error, meaning it’s vulnerable:
malloc(): corrupted top size
Aborted (core dumped)
To understand the problem with sudo, we have to understand escape characters. It really boils down to spaces in file and folder names, and how to deal with them. You want to name your folder “My Stuff”? That’s fine, but how do you interact with that directory name on the command line, when spaces are the default delimiter between arguments? One option is to wrap it in quotation marks, but that gets old in a hurry. The Unix solution is to use the backslash character as an escape character. Hence you can refer to your fancy folder as My\ Stuff. The shell sees the escape character, and knows to interpret the space as part of the folder name, rather than an argument separator. Escape characters are a common vulnerability location, as there are plenty of edge cases. Continue reading “This Week In Security: Sudo, Database Breaches, And Ransomware”
Every day in the US, seventeen people die because they couldn’t get a organ transplant in time. An American biotech company called United Therapeutics is looking to pick up the lifesaving slack by producing a line of genetically-modified pigs for the purpose of harvesting their organs, among other therapeutic uses. United Therapeutics’ pig-farming subsidiary Revivicor is a spin-off of PPL Therapeutics, the company that gave us Dolly the cloned sheep back in 1996. They intend to start transplanting pig organs into humans as early as this year.
Although it sounds like science fiction, the idea of transplanting animal cells, organs, and tissue into humans has been around for over a hundred years. The main problem with xenotransplantation is that it usually triggers severe immune system reactions in the recipient’s body. In one of the more noteworthy cases, a baby girl received a baboon heart in 1984, but died a few weeks later because her body rejected the organ.
The leading cause of xenotransplant rejection is a sugar called alpha-gal. This sugar appears on the cell surfaces of all non-primate mammals. Alpha-gal is problematic for other reasons, too: a condition called alpha-gal syndrome usually begins when a Lone Star tick bites a person and transmits alpha-gal cells from the blood of animals they have bitten. From that point on, the person will experience an allergic reaction when eating red meat such as beef, pork, and lamb.
Continue reading “Swine Of The Times: Pig-to-Human Organ Transplants On Track For 2021”
