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I wouldn't say "violence", rather, an opportunity to demolish something on (good) purpose. Same reason children will be glued to the window if workers outside are going at it with jackhammers, or, better yet, an excavator is crushing and scraping off the asphalt. (Yeah, I remember exactly how awesome that was.)

A custom 3D-printed user-matched disposable nozzle, perhaps? One could carry a handful in his pocket and don before the act.

I feel a laminar airflow which runs in parallel to the turbulent liquid flow to draw it into the receptacle would reduce waste.

What happens if you urinate through those bladeless Dyson fans?


I also loved the video. But I'd think if one wanted to deploy "simple" mechanical projectile weapons at scale, pneumatic launchers would be easier, more compact and more reliable (way less cool-looking and operating, though!).


like a potato cannon?

I helped design the "reloadable" part of a golf-ball shooter that used acetylene as the accelerant. I don't think it went supersonic, though. There's videos (embarassing ones) on youtube. He eventually designed one that can shoot full cans of monster energy hundreds of yards.

the reason i bring it up is we used to design and build pneumatic ones, that could send C and D batteries thousands of feet if you arced it right. that was with ~125psi, we always wanted to build out to 200+ psi, but instead went into accelerant-based cannons and he got a job doing machine drawing with autocad. the rest is history.

edit: https://nextcloud.projectftm.com/index.php/s/cobra5x we show off the part i designed, toward the end on the "reload" - he designed and built the entire thing.


Sorry to be a bore [that's a firearms joke], but -- while I encourage everyone and their family to experiment with building such devices, with safety in mind of course, it is a lot of fun -- please don't dispose of your old batteries in the natural environment!

Really not trying to call you out here, as a teenager I once had the idea to load up my marble cannon with dead AAs (they're free!) and got a "do you really think that's a good idea?" from an environmentally conscious adult when I went asking for dead batteries.


We moved on to oranges really fast after realizing that batteries coming out of the sky randomly was probably a bad idea, even if there were no apparent people around.

Don't get me wrong, oranges are dangerous too, coming out of the sky at terminal velocity, but at least when they hit the ground they disappeared into a fine, 3 meter wide mist.


oh my god, were it not for your redundant comment I might've gone to the forest to discard my collection of depleted batteries, thank goodness.


I think the cycle time on this would be far superior to a pneumatic system: cycling this system effectively means lifting ~100 pounds ~8 feet, which a reasonably fit person (who could reach that high) could do several times a minute for extended periods.

He got an efficiency over 40% (if memory serves, I watched this video yesterday) -- I wonder between pumping and discharge how efficient a pneumatic system would be, but I can't imagine that it's higher.


If the pump were operated by a bicyclist and the projectile feed automated I imagine the pneumatic system would win out by a very wide margin regardless of any reduction in overall efficiency.


I've seen potato guns (obviously much larger bore than this) and inflated bicycle tires to 100psi+

How do you imagine making the cycle time better "by a very wide margin" compared to lifting 100 pounds less than 10 feet?


Isn't it a simple matter of sustained energy output scaled by the overall efficiency? I'm saying that a human cycling can sustain much much higher energy output for much longer than most other forms of exercise. Running probably comes close and swimming likely exceeds both of those but in the latter two cases I'm not clear how you could productively harness energy from the activity with any sort of efficiency so it doesn't apply here.


Once this thing is dialed in, a wind- or stream- rechargeable version is the obvious next step.


Basically anyone can go buy a pellet rifle that will easily and consistently clear 1500fps. They're still pretty cool, and will go through both doors of a car


I dunno, takes a lot of energy to get a pneumatic system up to the same speeds that this trebuchet can accomplish. I see it really as a super-efficient machine requiring very little effort to load ..

But yeah, the fact that it's super cool looking - and sounding - is a key factor in my willingness to play with one too, one day. ;)


What a coincidence: just earlier today I noticed that normal search with "Tools/Past month" does not in fact filter by date (last time I used it some weeks ago, it had always worked fine). A temporary bug, I hope.


Oh, I thought it's about AI companies asking people to wear those little head-mounted cameras, in hopes of gathering data to train future robot-electricians.


On a related note, there's an annoying mistake in one of the Fatalities in "Mortal Kombat 1": Liu Kang teleports with his opponent into outer space, summons a black hole with a snap of his fingers, and throws the poor sod in. But the accretion disc is red where it rotates towards camera, and blue where it rotates away!


Boy, I really hope somebody got fired for that blunder.


I watched a related Chris Cappy video the other day:

https://www.youtube.com/watch?v=5RBY1cY-GF8

> Poland's elite GROM commandos have become legendary (...) in this episode, we explore (...) the covert war between Poland and Russia, and why Polish-speaking commandos are appearing inside Russian territory.


That ship has sailed, no? Plenty of code for voice generation out there already, you'd basically have to ban general computing.


Remember the "Black Mirror" episode "Metalhead"? (If not, check it out, no spoilers here.) I'm afraid we'll see something like this in the not-too-distant future.

Now, a squad of soldiers, or even just one experienced rifleman, would prob. dispatch of such a threat quickly. But against (at most poorly armed) civilians it would be an all too effective terror/area denial weapon.


Love that episode. The relentlessness of those drones is terrifying. I hope we civilians will have countermeasures against robots like those when the time comes...

Another interesting piece of fiction: Horizon Zero Dawn. AI robots armed to the teeth, fueled by biomass, capable of reproduction via onboard factories. They had to reset the planet.


Very similarly, the movie "Screamers" (I liked it more than Dick's original novelette). Hopefully, no one will decide to really seed a continent/planet with autonomous "oh, we can control them just fine" killer bots.


If it actually becomes a problem, I start carrying my shotgun everywhere, but... Even in the US, most Americans aren't particularly good with a shotgun. Enough of us that most places could have a number of people that they just call. Wake up right now and get out because you might need to shoot something, but it's a dangerous job and I really hope that it never comes down to that.


There's a video of a Finnish clay target champion taking on drones with a shotgun.

The first one gets him because he's unfamiliar with their flight paths.

After that he does better but it clearly shows that you'd have to be an expert to take down a drone with a shotgun.

Also there's a lot of air inside a shotgun spread, so even an on target shot may fail to disable a drone.


I'm reasonably good with clay targets. I would expect that if I was actually asked to take on drones I would need to do some practice on drones before I'd be good at them too. Drones are more expensive than clay targets but they're not particularly expensive and considering the situation I'd be willing to pay the price of a few drones to learn how to shoot them down down in a controlled setting where it's safe.

Shotguns have very short range: if I'm expected to be taking down a drone with a shotgun things are really bad at that point my life is alread in danger. if I hit I may save my life.


There is video out of Ukraine of Russians with shotguns shooting at drones. It’s not very effective.


Remember you are only seeing a selection of the thousands of times this has happened. The drone operating side will release more of the ones where it didn't work.

It does work at least sometimes. If it didn't work at all soldiers would not bother carrying the shotguns.

https://en.wikipedia.org/wiki/Use_of_shotguns_against_drones https://www.businessinsider.com/ukraine-soldiers-best-chance...


It would be surprise me if it is really true. It is probably one of the easier type of gun to pick up in terms of skill and shoot accurately. Still, 'shotgun minute men' has a ring to it.


Good news, amateur astronomy is still done on web forums - they're the place for newcomers to acquire knowledge, and for technical discussions among the more advanced. (Modern social media tend to be rather used for outreach to the lay public.)

Places like Cloudy Nights, Stargazers Lounge, Solarchat, and your country's biggest local-lang forum.


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