Software Bug Results In Insulin Pump Injuries, Spurs Recall

May 11, 2024 by Dan Maloney 24 Comments

Managing Type 1 diabetes is a high-stakes balancing act — too much or too little insulin is a bad thing, resulting in blood glucose levels that deviate from a narrow range with potentially dire consequences on either side. Many diabetics choose to use an insulin pump to make managing all this easier, but as a recent recall of insulin pump software by the US Food and Drug Administration shows, technology isn’t foolproof.

Thankfully, the recall is very narrow in scope. It’s targeted at users of the Tandem t:slim X2 insulin pump, and specifically the companion application running on iOS devices. The mobile app is intended to run on the user’s phone to monitor and control the pump. The pump itself is a small, rechargeable device that users often keep on their belt or tucked into a pocket that delivers a slow, steady infusion of insulin during the day, plus larger bolus doses to compensate for meals.

But version 2.7 of the t:connect mobile app can crash unexpectedly, and on iOS devices, that can lead to the OS continually relaunching it. Each time it does this, the app tries to reconnect with the pump via Bluetooth, which eventually runs down the battery in the pump. Once the battery is dead, no more insulin can be delivered, potentially leading to a condition called hyperglycemia (“hyper” meaning an excess, “gly” referring to sugar, and “emia” meaning presence in blood — excess sugar in the blood.)

Untreated hyperglycemia can progress to a much more serious state called diabetic ketoacidosis, which can lead to coma and death. Thankfully, nobody has suffered that fate from this bug, but the FDA has received over 200 reports of injuries, hence the recall. Tandem sent out a notice to all affected customers back in March to update their apps, but it’s still possible that some users didn’t get the message.

Apart from the human cost of this bug, there’s a lesson here about software design and unintended consequences. While it intuitively seems like a great idea to automatically relaunch a crashed app, especially one with a critical life-safety function, in hindsight, the better course might have been to just go into a safe mode and alert the user with an alarm. That’s a lesson we’ve learned by exploring space, and it seems to apply here as well.

Images: AdobeStock, Tandem Diabetes

The Impossible Repair: Ribbon Cables

May 11, 2024 by Jenny List 32 Comments

It’s a problem that faces many a piece of older equipment that ribbon cables of the type used on membrane keyboards start to fail as they become older. These cables are extremely difficult to repair as they can’t be soldered to, and since they are usually custom to the device in question. All is not lost, though, as [Spare Time Repair] shows us with the cable on a Honeywell heating controller broken by a user attempting to remove the battery with a screwdriver.

The whole process can be seen in the video below the break, and it involves the use of a vinyl cutter to cut the pattern of tracks in aluminium tape stuck on a sheet of acetate. This makes a new piece of ribbon cable, however it’s still a step short of being part of the circuit. His challenge is to make a clip tight enough to attach it to the intact part of the broken cable and maintain contact, then to hope that the new piece of cable bent back on itself can make enough contact for the device to work.

At the end of it all, he has a working Honeywell controller, though as he points out, it’s a device he has little interest in. Instead, this opens a window on an extremely useful technique that should be of relevance far beyond the world of heating. There’s one machine close to home for us that could use this technique, for example.

Continue reading “The Impossible Repair: Ribbon Cables” →

Institutional Memory, On Paper

May 11, 2024 by Elliot Williams 18 Comments

Our own Dan Maloney has been on a Voyager kick for the past couple of years. Voyager, the space probe. As a long-term project, he has been trying to figure out the computer systems on board. He got far enough to write up a great overview piece, and it’s a pretty good summary of what we know these days. But along the way, he stumbled on a couple old documents that would answer a lot of questions.

Dan asked JPL if they had them, and the answer was “no”. Oddly enough, the very people who are involved in the epic save a couple weeks ago would also like a copy. So when Dan tracked the document down to a paper-only collection at Wichita State University, he thought he had won, but the whole box is stashed away as the library undergoes construction.

That box, and a couple of its neighbors, appear to have a treasure trove of documentation about the Voyagers, and it may even be one-of-a-kind. So in the comments, a number of people have volunteered to help the effort, but I think we’re all just going to have to wait until the library is open for business again. In this age of everything-online, everything-scanned-in, it’s amazing to believe that documents about the world’s furthest-flown space probe wouldn’t be available, but so it is!

It makes you wonder how many other similar documents – products of serious work by the people responsible for designing the systems and machines that shaped our world – are out there in the dark somewhere. History can’t capture everything, and it’s down to our collective good judgement in the end. So if you find yourself in a position to shed light on, or scan, such old papers, please do! And then contact some nerd institution like the Internet Archive or the Computer History Museum.

Gather ‘Round This Unique 4-Player Arcade Cabinet

May 11, 2024 by Tom Nardi 4 Comments

Usually when we see arcade cabinet builds, they’re your standard single-player stand up variety. Even one of them takes up quite a bit of room, so as appealing as it might be to link up two or more cabinets together for the occasional multiplayer session, the space required makes it a non-starter for most of us.

But this cleverly designed 4-player cocktail cabinet from [OgrishGadgeteer] goes a long way towards solving that problem. The circular design of the cabinet gives each player a clear view of their respective display in a much smaller footprint than would otherwise be possible, and the glass top allows the whole thing to double as an actual cocktail table when it’s not game time.

The cabinet was modelled in 3D before construction.

According to a post on r/cade, it took [OgrishGadgeteer] three months to go from paper sketches of the cabinet’s basic shape to the final product. Most of the components were picked up on the second hand market, which brought the total cost of the build to around $350. That wouldn’t have been a surprising price for a traditional full-size cabinet build, so for this, it seems like an absolute steal.

A Dell OptiPlex 7060 small form factor PC provides the power for this build, with the video output passing through a 4-way VGA distribution amplifier into 20 inch monitors. At $75, the four player control kit ended up being the single most expensive component of the build, though you could make do with some parts bin buttons and a Pi Pico if you wanted to really bring this one in on a budget.

Perhaps the most surprising element of the whole build is that, despite the cabinet’s complex design, [OgrishGadgeteer] pulled it off without a CNC to cut the plywood panels. Instead, a vinyl cutter was used to make full-size templates of the cuts and holes that needed to be made, which were attached directly to the wood. After that, it was just a matter of following the lines with a jigsaw. Not the fastest or most convenient solution, but it’s hard to argue with the final results.

We’ve seen other cocktail cabinet builds in the past, but this is the first that managed to cram four players in. Well, unless you count Dungeons & Dragons, anyway.

Protoboard Z80 Computer Teaches The Basics

May 11, 2024 by Tom Nardi 16 Comments

As curious people, we’re all incredibly fortunate to live in an age where information can so easily be obtained. If you want to learn how something works, from a cotton gin to an RBMK reactor, you’re just a few keystrokes away from articles, diagrams, and videos on the subject. But as helpful as all of that information can be, we also know that there’s no substitute for hands-on experience.

While we can’t recommend you try building a miniature graphite-moderated nuclear reactor, there’s plenty of other devices that you can study by constructing your own functioning model. For example, when [Jorisclayton] wanted to really know what was going on inside a computer, they decided to go back to basics and build their own Z80 machine. To maximize the experience, they skipped any of the existing kit designs and instead wired the whole thing up by hand across a few perfboards.

The main board contains a 4 MHz Z80 processor, paired with 32K ROM and 64K RAM. Here you’ll also find the clock generator, I/O decoder, serial port, voltage regulator, and a trio of expansion slots that use a long strip of 2.54 mm pin headers as the interface. In the first expansion slot you’ve got a primordial “graphics card” based around the TMS9918 video display controller (VDC) and 16K of additional RAM. The second expansion card has a CompactFlash reader and an LED array mapped to I/O address 0x00h so it can be used for various notifications.

[Jorisclayton] says the final expansion board is still being worked on, but the idea is for it to handle user input through a PS/2 keyboard connector, as well as provide ports for a pair of Super Nintendo (or compatible) controllers. Everything is held together with a minimalist 3D printed frame to show off all that careful soldering.

Obviously there’s no PCB design files to share for this one, but [Jorisclayton] has posted a schematic for wiring everything up if you’re looking for resources to build your own Z80 computer. Sure the chips themselves might no longer be in production, but that doesn’t mean this venerable CPU is going anywhere just yet.

An Umbrella Can Teach A Thing Or Two About Product Longevity

May 10, 2024 by Jenny List 30 Comments

This time of year always brings a few gems from outside Hackaday’s usual circle, as students attending industrial design colleges release their final year projects, The worlds of art and engineering sit very close together at times, and theirs is a discipline which sits firmly astride that line. This is amply demonstrated by the work of [Charlie Humble-Thomas], who has taken an everyday object, the umbrella, and used it to pose the question: How long should objects last?

He explores the topic by making three different umbrellas, none of which we are guessing resemble those you could buy. The first is not particularly durable but is completely recyclable, the second is designed entirely with repairability in mind, while the third is hugely over-engineered and designed for durability. In each case the reader is intended to think about the impact of the umbrella before them.

What strikes us is how much better designed each one is than the typical cheap umbrella on sale today, with the polypropylene recyclable one being flimsy by design, but with a simplicity missing from its commercial counterpart. The durable one meanwhile is full of CNC parts, and carbon fiber.

If you’re hungry for more student work in this vein, we recently brought you this toasty typewriter.

Kaffa Roastery founder Svante Hampf shows a bag of their AI-conic coffee blend.

AI-Created Coffee Blend Isn’t Terrible

May 10, 2024 by Kristina Panos 12 Comments

Weren’t we just talking about coffee-based sacrilege the other day? Here’s something to make the single-origin bean snobs chew their espresso cups: an artisan roastery in Helsinki is offering a coffee blend created by artificial intelligence called AI-conic. The idea, of course, is that technology will lighten the workload needed to produce coffee.

This is an interesting development because Finland consumes the most coffee in the world, according to the International Coffee Organization. Coffee roasting is a highly-valued traditional artisan profession there, so it stands to reason that they might turn to technology for help.

Just like with scotch whisky, there’s nothing wrong with coffee blends outright. Bean blends are good for consistency, when you want every cup to taste pretty much exactly the same. Single-origin beans, though, are traceable to one location, and as a result, they usually have a distinct flavor based on the climate they’re grown in.

If you’re new to coffee, blends are a nice, safe way to start out. And, interestingly, the AI chose to make the blend out of four different types of beans instead of the usual two or three, despite being tasked with creating a blend that would suit the palates of coffee enthusiasts. But the coffee experts agreed that the AI blend was “perfect” and needed no human intervention. We probably won’t be getting to Finland anytime soon, so if you try it, let us know how it tastes!

Do you like cold brew? How would you like to be able to brew some in just three minutes?