How To Monitor Blood Pressure Without Raising It

Does anyone actually enjoy the sensation of being squeezed by a blood pressure cuff? Well, as Mom used to say, it takes all kinds. For those who find the feeling nearly faint-inducing, take heart: researchers at UC San Diego have created a non-invasive medical wearable with a suite of sensors that can measure blood pressure and monitor multiple biochemicals at the same time.

The device is a small, flexible patch that adheres to the skin. So how does it manage to measure blood pressure without causing discomfort? The blood pressure sensor consists of eight customized piezoelectric transducers that bounce ultrasonic waves off the near and far walls of the artery. Then the sensor calculates the time of flight of the resulting echoes to gauge arterial dilation and contraction, which amounts to a blood pressure reading.

This patch also has a chemical sensor that uses a drug called pilocarpine to induce the skin to sweat, and then measures the levels of lactate, caffeine, and alcohol found within. To monitor glucose levels, a mild current stimulates the release of interstitial fluid — the stuff surrounding our cells that’s rife with glucose, salt, fatty acids, and a few minerals. This is how continuous glucose monitoring for diabetes patients works today. You can check out the team’s research paper for more details on the patch and its sensors.

In the future, the engineers are hoping to add even more sensors and develop a wireless version that doesn’t require external power. Either way, it looks much more comfortable and convenient than current methods.

This Week In Security: Mysterious Mac Malware, An Elegant VMware RCE, And A JSON Mess

There’s a new malware strain targeting MacOS, Silver Sparrow, and it’s unusual for a couple reasons. First, it’s one of the few pieces of malware that targets the new M1 ARM64 processors. Just a reminder, that is Apple’s new in-house silicon design. It’s unusual for a second reason — it’s not doing anything. More precisely, while researchers have been watching, the command and control infrastructure didn’t provide a payload. Silver Sparrow has been positively found on nearly 30,000 machines.

The malware also has an intentional kill switch, where the presence of a particular file triggers a complete removal of the malware package. Researchers at Red Canary point out that this package behaves very much like a legitimate program, difficult to pick out as malware. Ars Technica got an off-the-record statement from Apple, indicating that they are tracking the situation, and have revoked the developer’s certificate used to sign the malware. It’s not entirely clear whether this prevents the malware running on already compromised machines, or just stops new infections.

So who’s behind Silver Sparrow? The observed stealth mode and other complexities suggest that this is more than a simple adware or ransomware campaign. Since it was discovered before the payload was delivered, we may never know what the purpose is. It may have been a government created campaign, targeting something specific. Continue reading “This Week In Security: Mysterious Mac Malware, An Elegant VMware RCE, And A JSON Mess”

Bad Week For Boeing: Reports Of Third Engine Failure Causes Emergency Landing In Moscow

Early Friday morning a Boeing 777 performed an emergency landing in Moscow, according to Russian media. The Interfax news agency cites an anonymous source who claims the landing was caused by an engine failure on a flight from Hong Kong to Madrid. According to the Hong Kong civil aviation department this was a cargo flight. So far no injuries have been reported.

Two damaged fan blades from UA328, a Boeing 777 that returned safely to DIA shortly after takeoff

Engine failures happen, pilots train for them, and our airport infrastructure is setup to accommodate emergency landings like this. However, the timing of this reported failure is notable. This is the second engine failure on a 777 within a week, and the third to occur in a Boeing aircraft.

Shortly after takeoff on Saturday, February 20th, a United Airlines flight bound for Hawaii made an emergency landing after suffering a catastrophic failure of the right engine. The event was widely shared on social media, you likely saw the video from a passenger inside the Boeing 777-200 that shows the damaged engine on fire — if you haven’t you really should. There was also damage on the ground due to falling debris. This prompted Boeing to launch inspections of all 777-200s, and soon afterwards the NTSB published photos of the damaged engine. No injuries have been reported.

Two days later, on February 22nd, a Boeing 747-400 cargo plane operated by Longtail Aviation suffered an engine failure over the Netherlands, dropping parts that reportedly injured two people on the ground. This is a different model of aircraft but uses a Pratt & Whitney PW4000, in the same family as the Pratt & Whitney PW4070/4090 on the United 777-200.

Reports of this morning’s emergency landing in Moscow will need to be verified and investigated, and we have not seen confirmation on what type of engine the Rossiya Airlines B777-300ER used. For comparison the 777-300ERs of the United fleet and the 777-300ERs operated by Emirates both use General Electric engines rather than Pratt & Whitney models, so it is likely the Rossiya aircraft also had a GE engine.

The fact that the flights were all able to make safe landings is a testament to the redundant engineering of these aircraft. CNET did a deep dive into last Saturday’s engine failure and notes that it was an Extended-range Operations Performance Standards (ETOPS) aircraft capable of flying long distances on a single engine — necessary if an aircraft needed to make it half-way to Hawaii on one engine for an emergency landing. They also report on two other Pratt & Whitney PW-4000 engine failures in 2018 and 2000 2020, although as mentioned before, today’s incident likely didn’t involve an engine from this maker.

[Main image source: B777-300 by Maarten Visser CC-BY-SA 2.0]

Art of 3D printer in the middle of printing a Hackaday Jolly Wrencher logo

3D Printering: To Print Stainless, You Do Half The Work

Everyone wants to print using metal. It is possible, but the machines to do the work are usually quite expensive. So it caught our eye when MakerBot announced a printer — armed with an experimental extruder — that can print stainless steel parts. Then we read a bit more and realized that it can only sort of do the job. It needs a lot of help. And with some reasonable, if not trivial, modifications, your printer can probably print metal as well.

The key part of the system is BASF Ultrafuse 316L Stainless Steel filament, something that’s been around for a few years. This is a polymer with metal incorporated into it. This explains the special extruder, since metal-bearing filament is hell on typical 3D printer nozzles. However, what comes out isn’t really steel — not yet. For that, you have to send the part to a post-processing facility where it is baked at 1380 °C in a pure hydrogen atmosphere using special equipment. This debinding and sintering produces a part that the company claims can be up to 96% pure metal.

Continue reading “3D Printering: To Print Stainless, You Do Half The Work”

San Jose Fry's Electronics

Fry’s Electronics Has Fizzled Out Completely

2020 and all its ills have claimed another stalwart among PC builders and electronics hobbyists: Fry’s announced yesterday that they have closed up shop for good after nearly 36 years in business both as a brick-and-mortar wonderland and an online mecca for all things electronic.

According to Fry’s website (PDF copy for posterity), all 31 stores across nine states were suddenly and permanently shuttered on Wednesday the 24th, citing changes in the retail industry and the widespread difficulties wrought by the pandemic. Signs of the retailer’s growing challenges were seen back in 2019 when the company began shifting toward a consignment model in an attempt to cut overhead and liability.

Burbank Fry’s electronics [Image source: Bryce Edwards CC-BY 2.0]
Sadly, I never set foot inside of a Fry’s though I hear it was an experience beginning with the themed entrances found at many of the locations. Now it seems I never will. Where I live, Microcenter is king, and it has been truly awesome to watch the hobby electronics section expand from a single four-foot panel in a dark corner to the multi-aisle marketplace it is today. I keep imagining that Microcenter suddenly went out of business instead, and it makes me want to cry.

So where can a person go to pick up some quick components now that Radio Shack and Fry’s are no more? Of course there’s the previously mentioned Microcenter, but you should also look for old-school supply stores in your area. They may not have an Adafruit section and they’re probably not open after 5:00PM or on the weekends, but these stores are still kicking and they need us now more than ever. We’ve previously reported on gems like Tanner’s Electronics which sadly closed its doors almost a year ago. Help spread the word about your favorites that are still open in the comments below.

Thank you [Ryan], [John], and [Jack] for tipping us off.

[Main image source: San Jose Fry’s by Bryce Edwards; CC-BY 2.0]

May (No Longer) Contain Hackers: MCH 2021 Has Been Cancelled

In a sad but unsurprising turn of events, MCH, this summer’s large hacker camp in the Netherlands, has been cancelled. Organising a large event in a pandemic would inevitably carry some risk, and despite optimism that the European vaccine strategy might have delivered a safe environment by the summer that risk was evidently too high for the event organisers IFCAT to take on. Our community’s events come from within the community itself rather than from commercial promoters, and the financial liability of committing to hire the site and infrastructure would have been too high to bear had the event succumbed to the pandemic. Tickets already purchased will be refunded, and they leave us with a crumb of solace by promising that alternatives will be considered. We understand their decision, and thank them for trying.

As with all such events the behind-the-scenes work for MCH has already started. The badge has been revealed in prototype form, the call for participation has been completed, and the various other event team planning will no doubt be well  under way. This work is unlikely to be wasted, and we hope that it will bear fruit at the next Dutch event whenever that may be.

It would have been nice to think that by now we could be seeing the light at the end of the pandemic tunnel, but despite the sterling work of scientists, healthcare workers, and epidemiologists, it seems we still have a a way to go before we’ll once more be hanging out together drinking Club-Mate in the company of thousands of others. If the pandemic is weighing upon you, take care of yourselves.

Stunning Footage Of Perseverance Landing On Mars

The much-anticipated video from the entry descent and landing (EDL) camera suite on the Perseverance rover has been downlinked to Earth, and it does not disappoint. Watch the video below and be amazed.

The video was played at the NASA press conference today, which is still ongoing as we write this. The brief video below has all the highlights, but the good stuff from an engineering perspective is in the full press conference. The level of detail captured by these cameras, and the bounty of engineering information revealed by these spectacular images, stands in somewhat stark contrast to the fact that they were included on the mission mainly as an afterthought. NASA isn’t often in the habit of adding “nice to have” features to a mission, what with the incredible cost-per-kilogram of delivering a package to Mars. But thankfully they did, using mainly off-the-shelf cameras.

The camera suite covered nearly everything that happened during the “Seven Minutes of Terror” EDL phase of the mission. An up-looking camera saw the sudden and violent deployment of the supersonic parachute — we’re told there’s an Easter egg encoded into the red-and-white gores of the parachute — while a down-looking camera on the rover watched the heat shield separate and fall away. Other cameras on the rover and the descent stage captured the skycrane maneuver in stunning detail, both looking up from the rover and down from the descent stage. We were surprised by the amount of dust kicked up by the descent engines, which fully obscured the images just at the moment of “tango delta” — touchdown of the rover on the surface. Our only complaint is not seeing the descent stage’s “controlled disassembly” 700 meters away from the landing, but one can’t have everything.

Honestly, these are images we could pore over for days. The level of detail is breathtaking, and the degree to which they make Mars a real place instead of an abstract concept can’t be overstated. Hats off to the EDL Imaging team for making all this possible.

Continue reading “Stunning Footage Of Perseverance Landing On Mars”