Hackaday Links: July 31, 2022

July 31, 2022 by Dan Maloney 12 Comments

Don’t look up! As of the time of this writing, there’s a decent chance that a Chinese Long March 5B booster has already completed its uncontrolled return to Earth, hopefully safely. The reentry prediction was continually tweaked over the last week or so, until the consensus closed in on 30 Jul 2022 at 17:08 UTC, give or take an hour either way. That two-hour window makes for a LOT of uncertainty about where the 25-ton piece of space debris will end up. Given the last prediction by The Aerospace Corporation, the likely surface paths cover a lot of open ocean, with only parts of Mexico and South America potentially in the crosshairs, along with parts of Indonesia. It’s expected that most of the material in the massive booster will burn up in the atmosphere, but with the size of the thing, even 20% making it to the ground could be catastrophic, as it nearly was in 2020.

[Update: US Space Command confirms that the booster splashed down in the Indian Ocean region at 16:45 UTC. No word yet on how much debris survived, or if any populated areas were impacted.]

Good news, everyone — thanks to 3D printing, we now know the maximum height of a dive into water that the average human can perform without injury. And it’s surprisingly small — 8 meters for head first, 12 meters if you break the water with your hands first, and 15 meters feet first. Bear in mind this is for the average person; the record for surviving a foot-first dive is almost 60 meters, but that was by a trained diver. Researchers from Cornell came up with these numbers by printing models of human divers in various poses, fitting them with accelerometers, and comparing the readings they got with known figures for deceleration injuries. There was no mention of the maximum survivable belly flop, but based on first-hand anecdotal experience, we’d say it’s not much more than a meter.

Humans have done a lot of spacefaring in the last sixty years or so, but almost all of it has been either in low Earth orbit or as flybys of our neighbors in the Sol system. Sure we’ve landed plenty of probes, but mostly on the Moon, Mars, and a few lucky asteroids. And Venus, which is sometimes easy to forget. We were reminded of that fact by this cool video of the 1982 Soviet landing of Venera 14, one of only a few attempts to land on our so-called sister planet. The video shows the few photographs Venera 14 managed to take before being destroyed by the heat and pressure on Venus, but the real treat is the sound recording the probe managed to make. Venera 14 captured the sounds of its own operations on the Venusian surface, including what sounds like a pneumatic drill being used to sample the regolith. It also captured, as the narrator put it, “the gentle blow of the Venusian wind” — as gentle as ultra-dense carbon dioxide hot enough to melt lead can be, anyway.

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Demonstrate Danger, Safely

July 30, 2022 by Elliot Williams 67 Comments

Dan Maloney and I were talking about the chess robot arm that broke a child’s finger during the podcast, and it turns out that we both have extreme respect for robot arms in particular. Dan had a story of a broken encoder wheel that lead to out-of-control behavior that almost hit him, and I won’t even get within striking distance of the things unless I know they’re powered off after seeing what programming errors in a perfectly functioning machine can do to two-by-fours.

This made me think of all the dangerous things I’ve done, but moreover about all the intensely simple precautions you can to render them non-risky, and I think that’s extremely important to talk about. Tops of my list are the aforementioned industrial robot arm and high powered lasers.

Staying safe with an industrial robot arm is as easy as staying out of reach when it’s powered. Our procedure was to draw a line on the floor that traced the arm’s maximum radius, and you stay always outside that line when the light is on. It’s not foolproof, because you could hand the ’bot a golf club or something, but it’s a good minimum precaution. And when you need to get within the line, which you do, you power the thing down. There’s a good reason that many industrial robots live in cages with interlocks on the doors.

Laser safety is similar. You need to know where the beam is going, make sure it’s adequately terminated, and never take one in the eye. This can be as simple as putting the device in a box: laser stays in box, nobody goes blind. If you need to see inside, a webcam is marvelous. But sometimes you need to focus or align the laser, and then you put on the laser safety glasses and think really hard about where the beam is going. And then you close the box again when you’re done.

None of these safety measures are particularly challenging to implement, or conceptually hard: draw a line on the floor, put it in a box. There were a recent series of videos on making Lichtenberg figures safely, and as a general rule with high voltage projects, a great precaution is a two-button deadman’s switch box. This at least ensures that both of your hands are nowhere near the high voltage when it goes on, at the cost of two switches.

If all of the safety precautions are simple once you’ve heard them, they were nothing I would have come up with myself. I learned them all from other hackers. Same goes with the table saw in my workshop, or driving a car even. But since the more hackery endeavors are less common, the “common-sense” safety precautions in oddball fields are simply less commonly known. It’s our jobs as the folks who do know the secrets of safety to share them with others. When you do something dangerous, show off your safety hacks!

Hackaday Podcast 179: Danger Chess, Corona Motors, An Omni-Walker, And A Fast Talking Telescope

July 29, 2022 by Dan Maloney 3 Comments

Join Hackaday Editor-in-Chief Elliot Williams and Staff Writer Dan Maloney for their take on the hottest hacks in a hot, hot week. We found a bunch of unusual mechanisms this week, like an omnidirectional robot that’s not quite wheeled but not quite a walker either. Or, if you’d rather fly, there’s a UAV that’s basically a flying propeller. There’s danger afoot too, with news of a chess-playing robot with a nasty streak, a laser engraver that’ll probably blind you, and a high-voltage corona motor that actually does useful work. We’ll use our X-ray vision to take a deep dive into a 60-GHz phased array antenna, let a baby teach a machine what it means to be hungry, and build a couple of toy cameras just for funsies. Balloons as a UI? Maybe someday, thanks to ultrasonic levitation. And we’ll wrap things up by snooping in on the Webb telescope’s communications, as we find out how many people it takes to make wire harnesses. Spoiler alert: it’s a lot.

Check out 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 here!

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This Week In Security: Symbiote, Smart Locks, And CosmicStrand

July 29, 2022 by Jonathan Bennett 23 Comments

Symbiote is a particularly nasty Linux rootkit, and we have the interesting case of two separate analysis releasing this week. Up first is [CyberMasterV] taking apart a very early sample of the malware. The primary purpose of Symbiote seems to be capturing SSH logins, and this version does so by hooking the Pluggable Authentication Modules (PAM) system to capture users logging in to the machine it resides on. It also watches for SSH and SCP binaries, and sniffs the terminal used by those binaries, thereby capturing outgoing credentials.

All this data gets packaged up as DNS queries and shuffled off to the Command and Control server. “Easy”, I hear you say, “just block DNS traffic to everywhere except a trusted DNS provider.” It’s more clever than that. The data is in the form of valid DNS subdomains. In full, it’s a DNS request to PacketNumber.MachineID.Data.px32.nss.atendimento-estilo[.]com, all appropriately encoded to be valid. Every request will be for a unique host name, so every request gets forwarded to the C&C controller, which does double duty as the authoritative DNS resolver for that domain. You might get some mileage out of blocking (or at least logging) very long DNS queries.

Symbiote also replaces the typical files and devices you would look at to find a potential problem. For instance, /proc/net/tcp is where the kernel reports open TCP connections. On an infected machine, a copy of this file is maintained by the malware, conveniently leaving out the connections resulting from the infections. Symbiote has a hook in fopen, so whenever a process tries to read this location, the read is redirected to the cooked version, neatly hiding the rootkit. This stealth feature is apparently also used to hide other malware from the same attackers that may be on the same machine.
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Your Own Engineering Workstation, With Mame

July 28, 2022 by Al Williams 19 Comments

There are some things that leave indelible impressions in your memory. One of those things, for me, was a technical presentation in 1980 I attended — by calling in a lot of favors — a presentation by HP at what is now the Stennis Space Center. I was a student and it took a few phone calls to wrangle an invite but I wound up in a state-of-the-art conference room with a bunch of NASA engineers watching HP tell us about all their latest and greatest. Not that I could afford any of it, mind you. What really caught my imagination that day was the HP9845C, a color graphics computer with a roughly $40,000 price tag. That was twice the average US salary for 1980. Now, of course, you have a much better computer — or, rather, you probably have several much better computers including your phone. But if you want to relive those days, you can actually recreate the HP9845C’s 1980-vintage graphics glory using, of all things, a game emulator.

The Machine

The HP9845C with a Colorful Soft Key Display

Keep in mind that the IBM PC was nearly two years away at this point and, even then, wouldn’t hold a candle to the HP9845C. Like many machines of its era, it ran BASIC natively — in fact, it used special microcode to run BASIC programs relatively quickly on its 16-bit 5.7 MHz CPU. The 560 x 455 pixel graphics system had its own CPU and you could max it out with a decadent 1.5 MB of RAM. (But not, alas, for $40,000 which got you — I think –128K or so.)

The widespread use of the computer mouse was still in the future, so the HP had that wonderful light pen. Mass storage was also no problem — there was a 217 kB tape drive and while earlier models had a second drive and a thermal printer optional, these were included in the color “C” model. Like HP calculators, you could slot in different ROMs for different purposes. There were other options such as a digitizer and even floppy discs.

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Electrolytes, They’re What Dehydrated Hackaday Writers Crave!

July 27, 2022 by Jenny List 106 Comments

The oddly prophetic 2006 comedy film Idiocracy features an isotonic drink called Brawndo, whose marketing continuously refers to its electrolytes as a miraculous property. Brawndo is revealed in the film to be useless for agricultural irrigation, but yesterday perhaps a couple of Hackaday writers could have used a bottle or two. At the MCH hacker camp, the record heat of a Dutch summer under the influence of global warming caused us to become dehydrated, and thus necessitated a trip to the first aid post for some treatment. We’d done all the right things, staying in the shade, keeping as cool as we could, eating salty foods like crisps, and drinking plenty of liquids, so what had gone wrong?

Perhaps Club-Mate Should Have An Isotonic Version

The answer will probably be obvious to trained observers, we’d become deficient in those electrolytes. Our bodily stocks of sodium and potassium salts had become exhausted by sweat and all that extra water requiring trips to the toilet, so while we weren’t dehydrated in liquid terms we had exhausted some of the essentials to our cellular function.

The symptoms would have been easy to spot given the right training, but at a hacker camp it was too easy to attribute a headache and tiredness to a late night. For me the point at which it became obvious something was significantly wrong came when my thought processes started to slow down and my movement became a lot less easy. I’m a long-distance walker and cyclist, yet here I was walking like an octogenarian. If I’d know what to spot I might also have noticed that I had stopped sweating despite the heat. I found a friend (Thanks Gasman!), and together we made our way to the first aid post. MCH2022 first aiders were very efficient, and I was given a cup of oral rehydration salts which restored me to health in a matter of minutes. Continue reading “Electrolytes, They’re What Dehydrated Hackaday Writers Crave!” →

Protecting The Hughes H4 Hercules With… Beach Balls?

July 26, 2022 by Ryan Flowers 45 Comments

While visiting the Evergreen Aviation & Space Museum in McMinnville, OR, USA over the weekend, I came across a hack.

In addition to the excellent displays on site and an area where one can watch a video on repeat, the museum offers guided tours for a very reasonable price. And it was during this tour that my life as an aviation geek changed forever. Why? I got to visit the flight deck of the H4 and even sit in the pilots seat where Howard Hughes sat when he flew the plane almost 75 years ago.

It was later in the tour, after I’d had a moment to take in the enormity of sitting in the seat, that I found a wonderful hack to share with you all: and it’s all about beach balls. Continue reading “Protecting The Hughes H4 Hercules With… Beach Balls?” →