Doing my first upgrade to FreeBSD 15 :3
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Doing my first upgrade to FreeBSD 15 :3
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undefined stefano@mastodon.bsd.cafe shared this topic on
Gli ultimi otto messaggi ricevuti dalla Federazione
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@annamam@mastodon.social hello and welcome to the #Fediverse
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@jwz I know. Some people don't
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Magnetic-Suspension Hoverboard is Only 11 Years Late
Anyone who saw Back to the Future II was disappointed when 2015 rolled around with nary a hoverboard in sight. There have been various attempts to fake it, but none of them quite have the feel of floating about wherever you’d like to go that the movie conveys. The little-known YouTuber [Colin Furze] has a new take on the idea: use magnets. Really big magnets.
If you’re one of [Colin]’s handful of subscribers, then you probably saw his magnetic-suspension bike. We passed on that one, but we couldn’t resist the urge to cover the hoverboard version, regardless of how popular [Colin] might be on YouTube. It’s actually stupidly simple: the suspension is provided by the repulsive force between alarmingly large neodymium magnets. In this case, two are on the base plate that holds the skateboard ‘trucks’, and two are on the wooden ‘deck’ that [Colin] rides upon.
Of course magnetic repulsion is a very unstable equilibrium, so [Colin] had to reduce the degrees of freedom. In his first test, that was with a pair of rods and linear bearings. That way the deck could only move in the z-axis, providing the sensation of hovering without allowing the deck to slide off its magnetic perch. Unfortunately those pins transferred too much vibration from the ground into the deck, ruining the illusion of floating on air.
After realizing that he’d never be able to ollie (jump) this massive beast of a skateboard, [Colin] decides he might as well use a longboard instead. Longboards, as the name implies, are long skateboards, and are for transportation, not tricks. The longboard gets the same massive magnets, but after a couple of iterations to find a smoother solution — including a neat but unsuccessful tensegrity-inspired version — ends up with a pair of loosely-fitted pins once again, though relocated to the rear of the board. From the rider’s perspective, it looks exactly like a hoverboard, since you can’t see underneath from that angle. According to [Colin], it feels like a hoverboard, too.
The only way to do better would be with eddy currents over copper, or superconductors over a magnetic track, but both of those methods limit you to very specific locations. This might be a bit of a fakeout, but its one with a degree of freedom. One, to be specific. You have to admit, it’s still less of a fake than the handle-less Segway we got in 2015, at least.
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@geeknik this sound like a dystopian fiction. Don’t wanna believe it.
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@haayman We do what we must because we can. Also if I don't then the answer won't be there when I forget and do the search again.
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@gianmarcogg03
Per non parlare quelli che dicono di essere privati e sicuri e poi vedi nella lista di siti collegati che si vede con NoScript vanno a pescare da google amazon ecc.
In questo caso il sito utilizza cookiebot, che proviene da UK ma la cui proprietà è USA, vanificando quindi qualsiasi idea di servizio completamente EU.
@informapirata @informatica
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@jwz this is soo stackoverflow to post the answer yourself 🤗
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@jon_ellis So I guess if this is on a machine where file vault matters for other accounts, your plan B is to make a Guest2 user and rsync it back to template from cron.
