Hackaday Links: August 22, 2021

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It’s usually pretty hard to miss when Boston Dynamics drops a new video of one or more of their robots doing something flashy. But in case you’ve been under a rock the last few days, you might want to check out the Atlas parkour video. We last saw a pair of Atlas robots busting some dance moves with a few other Boston Dynamics robots, and while that was an incredible demonstration of the level of control they’ve engineered, they really were just playing back a series of preprogrammed moves. The obstacle course demo, though, seems like something different. There’s a good overview of the demo in IEEE Spectrum, where they point out that this is the first time we’ve seen Atlas show off using all four limbs at once for coordinated motion — that sweet vault over the fence. And really, it’s hard not to watch such human-like moves and not think that it’s just somebody in a robot suit. Even the stumbles feel human. What’s even more fun, though, is the behind-the-scenes look at Atlas. Especially for the face-plants and fails.

August 19 was the 100th anniversary of the birth of Gene Roddenberry, the creator of Star Trek. In the process of just trying to build a fictional universe to tell some interesting stories and make a little money, he managed to spawn not only an enduring science-fiction franchise but also to inspire generations of future scientists and engineers. The number of things that Star Trek writers invented to move their stories along that later showed up as actual products is astonishing, as are the weird coincidences like placing the fictional planet Vulcan in orbit around star 40 Eridani, only to find out that there’s actually a potentially habitable exoplanet circling that star. As a salute to Roddenberry, the Deep Space Network was used last week to send a message to 40 Eridani. One of the big dishes at the Goldstone DSN site in California blasted the 20-kW signal out on Thursday, starting it on its 16.5-year journey to the stars. We looked for details on what was sent, but the only description was that it contained a 1976 recording by the Great Bird of the Galaxy himself. Whatever it was, it’ll take at least 33 years to see if we get a response. Mark your calendars.

I’ve been doing a lot of work on cars lately, a task made considerably more approachable by the fact that the newest vehicle in the family fleet is from 2004. I find working on cars very satisfying, and I’m dreading the day when we’re forced to replace one of our old-timers with something more modern and less amenable to driveway repairs. That said, there’s also a lot to like about newer vehicles, particularly electric vehicles. It would be nice to have a way to move away from ICE vehicles while still being able to work on your ride. But if Ford’s tease this week of an EV crate motor comes to pass, it just might be the best of both worlds. The motor, bearing the unfortunate moniker “Eluminator” — just can’t resist putting that “E” in there, can they? — is supposed to be a drop-in replacement for an internal combustion engine, suitable for a “restomod” project. These car builds aim to make a car look as vintage as possible, but radically change the guts to add functionality — think a Raspberry Pi running a Spotify client that’s stuffed into a vintage Atwater Kent cathedral radio. We like the idea of electrifying an old car, but it seems to us that a crate motor is only part of the answer. Is there such thing as a crate battery?

And finally, there was an interesting article detailing a new approach to repairing ruptured eardrums using 3D printing. The tympanic membrane is a thin, delicate sheet of tissue that is easily punctured, whether by blunt-force trauma, infections, or even by loud sounds like gunshots or explosions. Hearing is compromised when an eardrum is damaged, and the hole can serve as a route for pathogenic microorganisms to get into the inner ear. Fixing the hole usually requires a graft from the patient’s own tissues, often sourced from the little dongle covering the ear canal. But this tissue isn’t nearly as thin as the natural eardrum, and while hearing can be restored, it’s often muddy and muffled. The new technique is to 3D-print a custom graft for the patient, using a special polymer and printer. The artificial membrane mimics the structure of the natural tympanic membrane and restores more natural hearing immediately. It also serves as a scaffold for the body to fill in with natural cells, hopefully returning natural function as the 3D-printed part is absorbed. It’s interesting work, and the video in the linked article is pretty fascinating too.

22 thoughts on “Hackaday Links: August 22, 2021

  1. > We looked for details on what was sent, but the only description was that it contained a 1976 recording by the Great Bird of the Galaxy himself.

    The Great Bird of the Galaxy was the nickname of Star Trek creator Gene Roddenberry, given to him by Associate Producer Robert Justman.
    ( https://memory-alpha.fandom.com/wiki/Great_bird_of_the_galaxy )

    Maybe it was related in some way to this 1976 article The Great Bird of the Galaxy:

    1. 20 kW (73.0103 dBm)
      S-band transmitter @ 2.29 to 2.30 GHz
      16.5 light years would have a Free Space Path Loss of about: 383.2 dB to 383.5 dB

      I’ll skip the maths but to receive the message that was sent would require an antenna with a diameter of about half that of our solar system.
      To put that into perspective:
      The diameter of earth is about 12.7 thousand kilometres
      The distance from earth to the sun is 149.6 million kilometres
      The diameter of the solar system is barely 287.46 billion kilometres

      We will never have the receiver built in only 33 years, we probably could not even do it in 33 million years. Talk is cheap, but listening, truly listening is going to be damn expensive! And only 16.5 light years would be a local call.

      1. Huh? Did you forget the transmitter gain? Should be above ~60 dB, and you only need ~150 dB to get an SNR of 1 against thermal noise of ~-100 dBm. That’s big, but not “half the solar system” big. Diameter of the Earth would be enough to do it.

        1. Not sure you fully understood what he said. He said transmitted power of 73 dBm, and path loss of 383 dB. This does not include the antenna gains on both ends, which are the numbers to solve for. With the numbers given (+73 dBm transmit, -100 dBm receive) we have a budget of 173 dB, of which we have -383 dB of path loss. Which means the total of the antenna gains needs to be at least 383-173 = 210 dB. Which may not be impossible, but it’s still a huge challenge. And just to make it more fun, while WE know exactly what direction to beam the power to, which puts a lot of antenna gain on our end, we have to assume that the receiver isn’t specifically looking for something coming from the Sol system, so their antenna gain is going to be a lot less, given similar technologies. But that’s just the Sol-Eridani transmission. Presumably on the reply transmission, they will pinpoint us as precisely as they can.

          1. Except we *already know* the transmitter gain is 60 dB. It’s a 70 m dish. And so you need around 150 dB of gain, which yeah, is huge, but not “half the size of the solar system” huge. Like I said.

    2. It also shows up in a scene from an episode of Star Trek itself, namely Mantrap, as when Rand enters the Botany lab to bring Sulu a snack, and he says that about the lady bringing him that snack.

  2. “Fixing the hole usually requires a graft from the patient’s own tissues, often sourced from the little dongle covering the ear canal.”

    Or medicine for a couple weeks.

  3. There is no reason to electrify proper ‘vintage’ cars because there are too few of them in daily use, to make any significant impact on the environment.
    This has been tested in Rotterdam, where for 1 or 2 years they prohibited all cars from before 1990 or so.
    After measuring carefully and for a long enough time, they found out that there was no measurable difference before and after instating the ban.
    This was because although per kilometer traveled the old cars pollute more, the total amount of kilometers done in older cars is just too small. Vintage cars are in general only used for nice weekend rides, and there are also only few of those cars left, compared to the stuff people drive everyday. Too few old cars that drive too little to make an impact.

    After a few court cases, the ban was overthrown and the couple of old cars in Rotterdam were allowed to be there again.

    1. Which ALMOST makes a good case. The cars banned were 30 years old or older. At the point we find a need to ban ICE-powered cars, most of them will be about 10 years old. Completely different situation.

      1. Plus when you’re talking vintage cars, at those times the vehicles weren’t really capable of surviving 30 years without serious effort and maintenance. Nowadays *many* cars should be able to run 20 years if kept out of worst conditions (garage kept, rust avoided, etc.) and maintained.

        I don’t see how stuff like this helps, though: it’s still a rich person’s solution. I don’t know how you fix the problem considering perfectly usable ICE vehicles are sub-$5k and I seriously can’t imagine EVs getting there.

          1. [Pat], I didn’t mean my response to be a criticism of your comment. I was just expounding on it.
            If ICEs are banned, and electric cars aren’t, people will keep theirs even if it means pouring bathtub gin into their gas tanks.

  4. Wait a second, it is quite possible that Vulcans have already received the message, intercepted by one of their craft monitoring human civilization, and relayed by subspace radio to their planet. But, since it is a fact that they will not contact us until we are able to warp travel, They will choose not to reply…

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