An Exoskeleton Arm For A Hacker On A Budget

August 2, 2019 by 4 Comments

Whether it is motivated by a dream of superhuman strength courtesy of a mech suit or of mobility for those with impaired muscle function, the powered exoskeleton exerts a curious fascination among engineers. The idea of a machine-augmented human body achieving great things is thwarted though by the difficulty of the task, actuators and power sources small enough to be worn comfortably represent a significant challenge that is not easily overcome. It’s a subject that has captivated [Kristjan Berce] since at a young age seeing his grandmother struggling with lifting, and he presents a working powered exoskeleton arm as a proof of his ideas.

It’s a wonderful exercise in low-tech construction with hand tools and a drill press on pieces of aluminium and wood. Motive power comes from an automotive windscreen wiper motor, and electrical power comes from a hefty LiPo attached to the device’s harness. There is a feedback potentiometer incorporated into the elbow joint, and an Arduino oversees the operation under the direction of a pair of glove-mounted buttons. It’s certainly impressive to see it in the video below lifting a bicycle, though we wonder how its weight might affect someone with less muscle function than average.

Projects like this one are very good to see, because there’s a chance that somebody out there may be helped by building one of these. However there is always a note of caution to be struck, as the best solutions come from those who need them and not those who merely think they have the solution. We have written about the Engineer Saviour Trap here in years past.

This isn’t the first prosthetic arm we’ve seen though, we covered a hackerspace in England printing one for a local youngster.

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RTL-SDR: Seven Years Later

July 31, 2019 by 40 Comments

Before swearing my fealty to the Jolly Wrencher, I wrote for several other sites, creating more or less the same sort of content I do now. In fact, the topical overlap was enough that occasionally those articles would get picked up here on Hackaday. One of those articles, which graced the pages of this site a little more than seven years ago, was Getting Started with RTL-SDR. The original linked article has long since disappeared, and the site it was hosted on is now apparently dedicated to Nintendo games, but you can probably get the gist of what it was about from the title alone.

An “Old School” RTL-SDR Receiver

When I wrote that article in 2012, the RTL-SDR project and its community were still in their infancy. It took some real digging to find out which TV tuners based on the Realtek RTL2832U were supported, what adapters you needed to connect more capable antennas, and how to compile all the software necessary to get them listening outside of their advertised frequency range. It wasn’t exactly the most user-friendly experience, and when it was all said and done, you were left largely to your own devices. If you didn’t know how to create your own receivers in GNU Radio, there wasn’t a whole lot you could do other than eavesdrop on hams or tune into local FM broadcasts.

Nearly a decade later, things have changed dramatically. The RTL-SDR hardware and software has itself improved enormously, but perhaps more importantly, the success of the project has kicked off something of a revolution in the software defined radio (SDR) world. Prior to 2012, SDRs were certainly not unobtainable, but they were considerably more expensive. Back then, the most comparable device on the market would have been the FUNcube dongle, a nearly $200 USD receiver that was actually designed for receiving data from CubeSats. Anything cheaper than that was likely to be a kit, and often operated within a narrower range of frequencies.

Today, we would argue that an RTL-SDR receiver is a must-have tool. For the cost of a cheap set of screwdrivers, you can gain access to a world that not so long ago would have been all but hidden to the amateur hacker. Let’s take a closer look at a few obvious ways that everyone’s favorite low-cost SDR has helped free the RF hacking genie from its bottle in the last few years.

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This Week In Security: Selfblow, Encryption Backdoors, Killer Apps, And The VLC Apocalypse That Wasn’t

July 26, 2019 by 18 Comments

Selfblow (Don’t google that at work, by the way) is a clever exploit by [Balázs Triszka] that affects every Nvidia Tegra device using the nvtboot bootloader — just about all of them except the Nintendo Switch. It’s CVE 2019-5680, and rated at an 8.2 according to Nvidia, but that high CVE rating isn’t entirely reflective of the reality of the situation. Taking advantage of the vulnerability means writing to the boot device, which requires root access, as well as a kernel flag set to expose the boot partitions to userspace. This vulnerability was discovered as part of an effort by [Balázs] and other LineageOS developers to build an open source bootloader for Nvidia Tegra devices.

The Tegra boot process is a bit different, having several stages and a dedicated Boot and Power Management CPU (BPMP). A zero-stage ROM loads nvtboot to memory and starts it executing on the BPMP. One of the tasks of nvtboot is to verify the signature of the next bootloader step, nvtboot-cpu. The file size and memory location are embedded in the nvtboot-cpu header. There are two problems here that together make this vulnerability possible. The first is that the bootloader binary is loaded to its final memory location before the signature verification is performed. The code is written to validate the bootloader signature before starting it executing on the primary CPU, so all is well, right? Continue reading “This Week In Security: Selfblow, Encryption Backdoors, Killer Apps, And The VLC Apocalypse That Wasn’t” →

Brain-Computer Interfaces: Separating Fact From Fiction On Musk’s Brain Implant Claims

July 24, 2019 by 81 Comments

When it comes to something as futuristic-sounding as brain-computer interfaces (BCI), our collective minds tend to zip straight to scenes from countless movies, comics, and other works of science-fiction (including more dystopian scenarios). Our mind’s eye fills with everything from the Borg and neural interfaces of Star Trek, to the neural recording devices with parent-controlled blocking features from Black Mirror, and of course the enslavement of the human race by machines in The Matrix.

And now there’s this Elon Musk guy, proclaiming that he’ll be wiring up people’s brains to computers starting next year, as part of this other company of his: Neuralink. Here the promises and imaginings are truly straight from the realm of sci-fi, ranging from ‘reading and writing’ to the brain, curing brain diseases and merging human minds with artificial intelligence. How much of this is just investor speak? Please join us as we take a look at BCIs, neuroprosthetics and what we can expect of these technologies in the coming years.

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The Great Moon Hoax — No Not That One!

July 23, 2019 by 65 Comments

Humans first walked on the moon 50 years ago, yet there are some people who don’t think it happened. This story is not about them. It turns out there was another great conspiracy theory involving a well-known astronomer, unicorns, and humanoids with bat wings. This one came 134 years before the words “We chose to go to the moon” were uttered.

The 1835 affair — known as the Great Moon Hoax — took the form of six articles published in The Sun, a newspaper in New York City. Think of it like “War of the Worlds” but in newspaper form — reported as if true but completely made up. Although well-known astronomer John Herschel was named in the story, he wasn’t actually involved in the hoax. Richard Adams Locke was the reporter who invented the story. His main goal seemed to be to sell newspapers, but he also may have been poking fun at some of the more outlandish scientific claims of the day.

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Forget The Walkman: It’s The Headphones

July 22, 2019 by 27 Comments

Forty years ago this month, a product was launched  in Japan that would have such a huge impact on the consumer electronics market that we are still using its descendants today. The story goes that one of the Sony founders would listen to music while traveling for the business, and found the company’s existing products cumbersome and awkward so asked his engineers to design something more convenient.

The resulting prototype became the Sony MDL-3L2, a set of miniaturised hi-fi headphones with distinctive foam earpads and a sliding metal headband that in total weighed an astoundingly svelte 45 g. It was paired with a cassette player called a “Walkman” derived from the company’s existing recorder that had been intended for journalists, and went on to sell in the millions. The market for headphones would never be the same again, and if you have a set of lightweight cans in your possession then this was their revolutionary progenitor.

But Hang On, What’s So Special About Headphones?

You probably won’t have heard the Walkman’s 40th anniversary described in those terms in the various reports covering the event, because of course the social impact of the portable music player rather than its headphones is what people remember. The joy of making a mix tape, of listening to The Human League on the bus, and of the adult disapproval of anything involving Kids Having Fun. Previously, music had been a static affair involving bulky record players, but now it could be taken anywhere. The other youth audio icon of that era, the boombox, simply couldn’t match the Walkman, and everybody wanted one.
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Hackaday Links: July 21, 2019

July 21, 2019 by 17 Comments

Ordering a PCB used to be a [Henry Ford]-esque experience: pick any color you like, as long as it’s green. We’ve come a long way in the “express yourself” space with PCBs, with slightly less than all the colors of the rainbow available, and some pretty nice silkscreening options to boot. But wouldn’t it be nice to get full-color graphics on a PCB? Australian company Little Bird thinks so, and they came up with a method to print graphics on a board. The results from what looks like a modified inkjet printer are pretty stunning, if somewhat limited in application. But I bet you could really make a splash with these in our Beautiful Hardware contest.

The 50th anniversary of the Apollo 11 landing has come and gone with at least as much fanfare as it deserves. Part of that celebration was Project Egress, creation of a replica of the Columbia crew hatch from parts made by 44 hackers and makers. Those parts were assembled on Thursday by [Adam Savage] at the National Air and Space Museum in an event that was streamed live. A lot of friends of Hackaday were in on the build and were on hand, like [Fran Blanche], [John Saunders], [Sophy Wong], and [Estefannie]. The Smithsonian says they’ll have a recording of the stream available soon, so watch this space if you’re interested in a replay.

From the “Don’t try this at home” department, organic chemist [Derek Lowe] has compiled a “Things I won’t work with” list. It’s real horror show stuff that regales the uninitiated with all sorts of chemical nightmares. Read up on chlorine trifluoride, an oxidizer of such strength that it’s hypergolic with anything that even approaches being fuel. Wet sand? Yep, bursts into flames on contact. Good reading.

Continuing the safety theme, machinist [Joe Pieczynski] offers this lathe tip designed to keep you in possession of a full set of fingers. He points out that the common practice of using a strip of emery cloth to polish a piece of round stock on either a wood or metal lathe can lead to disaster if the ends of the strip are brought into close proximity, whereupon it can catch and act like a strap wrench. Your fingers don’t stand a chance against such forces, so watch out. [Joe] doesn’t share any gory pictures of what can happen, but they’re out there. Only the brave need to Google “degloving injury.” NSFL – you’ve been warned.

On a happier note, wouldn’t it be nice to be able to print water-clear parts on a standard 3D printer? Sure it would, but the “clear” filaments and resins all seem to result in parts that are, at best, clearish. Industrial designer [Eric Strebel] has developed a method of post-processing clear SLA prints. It’s a little wet sanding followed by a top coat of a super stinky two-part urethane clearcoat. Fussy work, but the results are impressive, and it’s a good technique to file away for someday.