Comment by carapace | Hacker News Reader

Comment by carapace | Hacker News Reader

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"Build a better mousetrap and the world will beat a path to your door." is bunk. People don't automatically adopt new better things. I don't know why though.

In my teens and twenties I collected ideas the way some folk collect stamps. The simple fact of the matter is that there are amazing things out there that you've never heard of, and no one really seems to care.

(As an aside, I hate the question, "If FOO is so great why doesn't everyone use it?" I do not know. That's not my department.)

These days some of these things are better known and some even have Wikipedia pages and stuff ( E.g. https://en.wikipedia.org/wiki/Vaneless_ion_wind_generator ) but a lot of others are still obscure (trawl through Rex Research if you want to look for weird tech.)

Like, there's a mechanism that can absorb kinetic energy. The demo has a little car on rails with a ramp at one end and a wall at the other. They put a wineglass at the wall and they put the car on the ramp and let it go: the glass shatters. They activate the device and repeat: car hits glass and halts, glass does not shatter. Messed up, right? They're from Poland IIRC, they've been doing demos at trade shows. I bet you've never heard of them. (Bug me and I'll try to dig up a link; They're in Rex Research.)

I already mentioned the "Vaneless" ion wind generator, an efficient solid-state device for converting wind into electric power without e.g. killing birds with spinning vanes. Cheap, simple, easy, durable, been around for decades, and you just now heard about it, eh? :)

There's a battery that desalinizes salt water. A nuclear reactor made of molten salt. Balloons stronger than steel. There's a guy in Michigan, Wally Wallington, who figured out how to move monoliths single-handedly, they walk just like the old stories say!

Anyway, I'm getting ranty here. To veer back on topic: yeah, it's a bummer, you build an awesome mousetrap and even the people with lots of mice ignore it. I wish I knew what to tell you. Maybe paint it mauve?

These examples provide your answer - digging just past the surface, they're not better at giving people what they want.

The vaneless ion generator is >5x less efficient.

Molten Salt Reactors, on the surface, sound quite safe, but nuclear power's primary problem is economics, and this is an unproven technology operating over the long time scales needed to amortize reactor construction costs. Nuclear power systems present novel failure mechanisms that don't exist in everyday technology, such as the corrosion mechanisms caused by coupling of mechanical, thermal, chemical, and radiological stresses, and MSR's present a new set of these that are poorly understood. Additionally, MSR's exhibit thermal shocks in normal operations orders of magnitude above what may be produced in a water-cooled reactor.

It's just not that simple - it looks simple to you.

And yet the molten-sodium and molten-lead reactors, which sound quite unsafe, actually exist and used even today, since the seventies, actually.

Yes, they actually exist in the West as research reactors, since there has been no demonstration or certification of their suitability for long-term operation.

It seems to me like you're just being circular now, like you're saying "Sure, MS reactors exist, but we don't know if they are good because we haven't done the work to find out."

Going back to the original article "Why isn't differential dataflow more popular?" we could ask "Why aren't Molten Salt reactors more popular?"

There are usually multiple sane reasons why these ideas don't make it; either technological, practical, business or social hurdles. Conformism is one of them. They aren't actually better than what they are going against until they overcome that, or offer some kind of massive advantage that makes it dumb not to switch.

I've heard that, I don't buy it. I think we are just stupid and crazy.

Biodegradable plastic has been a thing for over half a century yet the whole planet is choking on discarded plastic. Where's the sane reason for that?

Cars!

Cars aren't sane, we had to convince ourselves that they were though a deliberate campaign of domestic propaganda![1] Cars kill hella people (I don't have stats for the rest of the world but more Americans have been killed by cars than have died in all the wars we've fought!) And that's just the people that get hit. There's air pollution (car exhaust is a deadly poison) and tires are constantly wearing down and giving off vulcanized rubber particles. I won't deny their convenience, but you'll never convince we they're sane.

Or my old pet peeve: refrigerators. They open like cabinets instead of like drawers. The cold air goes out, the warm air goes in, and you get to pay for the energy to cool it off. Why not make them like a chest of drawers?

Sanity? I think not.

[1] "The Real Reason Jaywalking Is A Crime" (Adam Ruins Everything) https://www.youtube.com/watch?v=vxopfjXkArM)

Replying here to the other fella:

> The vaneless ion generator is >5x less efficient.

C'mon, less efficient by what metrics? Total cost over the lifetime of the structure, including maintenance? Killing eagles?

In re: Molten Salt reactors there's a old page[1] about Molten Salt tech in general that talks about reactors towards the end:

> The second MSR was a civilian power plant prototype, the Molten Salt Reactor Experiment (MSRE)7. Hugely successful, it was ignored by the US Atomic Energy Commission (US AEC), which had decided to favor the Liquid Metal Fast Breeder Reactor (LMFBR). The Director of ORNL, Dr. Alvin Weinberg, pushed for the MSR, but was fired for his efforts 8.

> 8. Pages 198 - 200, "The First Nuclear Era : The Life and Times of a Technological Fixer", by Alvin Martin Weinberg (1994).

I've read a longer history of Molten Salt reactors that described the events referenced in the above quote. Evidently both kinds of reactor showed promise early on (MS and LMFB) but for bureaucratic reasons the one was passed over for the other.

[1] https://web.archive.org/web/20040602210408/http://home.earth...

Or my old pet peeve: refrigerators. They open like cabinets instead of like drawers. The cold air goes out, the warm air goes in, and you get to pay for the energy to cool it off. Why not make them like a chest of drawers?

This one has an easy answer. If you want to isolate each of the drawers so that opening one does not result in the warming of the others, then you'll need a separate mechanism for blowing cold air into each drawer. (Or worse, a separate cooling coil for each drawer.) These are expensive mechanical components prone to failure, and each of these mechanisms takes up valuable space in the fridge. They may provide some long term amortized savings over the energy cost if done correctly, but it's not at all obvious to me that would be the case without seeing the math worked out.

Newer designs are actually integrating drawers of all sorts of configurations and even mini limited drawers/access for guests while entertaining and what not.

Speaking of refrigerators, they should pull cold air from outside and vent hot air into the house. For roughly half the year where we are, a fridge would just cycle outside air. But no, it has to fight the internal house temp for the whole year.

Sanity? I think not.

See, this is exactly the point. When something that seems obvious is not happening, most of the time it just means there is a gap in your understanding.

Unless you live in the north pole and get outside temps in the 3°C range, this idea is already a no-go. Refrigerators are pretty efficient, using the same energy as a single incandescent lamp. They are not fighting the internal house temperature at all - compressors/heat pumps actually get less efficient at colder temperatures, and the heat it sheds off is offsetting your heating costs.

I'll bite, but you haven't shown anything and have sprinkled your comment full of rhetorical devices and fallacies.

The average upfridge at homedepot (USA) consumes 500kWh ish a year. This is to cool down from an internal ambient of 20C. It absolutely takes more work to cool from 20C than it does 10,5 or 0C. This is the conservation of energy. Cooler _efficiency_ changes as it approaches the setpoint do not mean that I can have free energy by having a larger delta.

Modern refrigerators have been designed specifically (forced by the government) because they are always-on devices that in aggregate consume large amounts of energy. You are conflating low power and always-on consumption of energy.

I'll absolutely engage with you, but it needs to be over facts and mathematics and not hand wavy arguments about "pretty efficient" vs a incandescent lamp.

https://openstax.org/books/physics/pages/12-2-first-law-of-t...

This is a great thread, thanks. Familiarity is a powerful thing. It helps explain why excel remains the most widely used “programming language” in enterprise.

Part of it is habits, which are not easy to change. And the fact that when they are changed, it’s often incrementally, by substituting them with something similar enough.

Thanks for the reminder of the amazing things that are out there, but just haven’t cracked the mainstream. I think about it a lot with software from the 90s. Things like HyperCard. Stuff that, despite lower processor rates and memory, seemed MORE sophisticated than a lot of what’s standard today.

Cheers!

And yes! HyperCard is a great example. Really picking on the IT industry is like taking candy from a baby, we're so woefully ignorant of our own prior art.

>there's a mechanism that can absorb kinetic energy

Yes, it's called braking.

"The demo has a little car on rails with a ramp at one end and a wall at the other." any link for that?

https://www.youtube.com/watch?v=z-h56N_A3rY It's in Polish. They also drive a real car into one of these things set up as a bumper!

News articles, links to more videos, patents, etc.: http://www.rexresearch.com/lagiewka/lagiewka.htm

I think you fell for a trickster.

"A small Fiat 126p, going 45 km per hour, was driven into a concrete wall. The bumper was not damaged. The driver wore no seatbelts. The inertial reaction, which should have thrown him onto the hood, did not ocur. The stopping distance was only 16 centimetres. Impossible? Yet hundreds of people in, and the stadium, and millions more on television. The use in all vehicles of the absorber of the energy, "Ecollision", can radically improve automobile safety."

Regardless of the mechanism of energy absorption, if a vehicle is decelerated from 45 kph to 0 within 16 centimeters, there needs to be a way to remove the kinetic energy from the driver inside as well (seatbelts). If not, they will simply continue flying along at 45 kph, through the windshield. If the driver in this case was not wearing seatbelts, it's quite likely that the vehicle was not going that quickly.

``Lagiewka says, "The technical idea behind my buffer can be used in very many practical solutions. Another invention which I showed experimentally, is the brake. Connected to the axis on a Mercedes, the car stopped in one-quarter of the distance usually required".''

When braking, the limiting factor is usually not the brake mechanism itself (e.g. the disc brakes), but the interface between tires and the road. That's why cars have anti-lock systems.

> I think you fell for a trickster.

It's possible. I certainly haven't tried to replicate the mechanism.

In the video you can see the driver does experience "the inertial reaction" when the car halts, at least it seems to me that he leans forward due to inertia at that moment. I think that description is just bad. (Or, of course, it was just a weird hoax.)

If I do not calculate wrongly on my back of envelope, to brake from 10m/s (36km/h) in 10cm you need constant 50g acceleration on the driver... he certainly should feel that. Yes, it is a con.

Meaning no disrespect, I don't see why your "back of envelope" estimate (which you didn't actually share) should be given more credit than the video. Like I said, I think that written description is simply wrong. It wouldn't be the first time a journalist misreported the details of some technology, eh?

I just watched the video again with the playback speed at 1/4 (thanks Youtube!) and at 0:46 ( https://youtu.be/z-h56N_A3rY?t=45 ) when the car hits the bumper I can clearly see the driver lean forward due to inertia. Of course you still need to wear a seatbelt, this isn't magic. (You know on Star Trek how the Klingon disruptors make a person disintegrate, clothes and all, yeah? How does the disintegration process know to stop at the floor? What is it about the interface between boots and floor which stops the disintegration? Could you use that to make disintegration-proof armour?) I get what you're saying. I do.

The point is not that the driver magically didn't feel inertia (he did, and you can clearly see it in the video) it's that the car didn't crumple. The kinetic energy given up by the stopping car went into the flywheel rather than into violent deformation of the physical structure of the car. I.e. it works (if it works at all, I don't deny that it might be a hoax) like a "crumple zone" without the crumple:

> Crumple zones are designed to increase the time over which the total force from the change in momentum is applied to an occupant ...

~ https://en.wikipedia.org/wiki/Crumple_zone

> The point is not that the driver magically didn't feel inertia (he did, and you can clearly see it in the video)

He clearly didn't experience 50g deceleration, he would have been sent flying through the windshield.

What's more likely is that the car actually did take a lot more than 16cm to slow down to 0 m/s or that it wasn't going at 45km/h. I would bet on the second, the car looks like it's going at maybe 20km/h in the video.

> The kinetic energy given up by the stopping car went into the flywheel rather than into violent deformation of the physical structure of the car.

That's an interesting idea but if it ends up being less effective at protecting the humans inside I don't think most people will choose it over normal crumple zones.

> if it ends up being less effective at protecting the humans inside

Of course. Who cares if you can just reset the flywheel (as opposed to scrapping the crumpled car) if you still have to scrap the people off of the dashboard?

My whole point is that there are devices like this one that may be more effective, given some R&D, but that get neglected.

Let me put forward another, perhaps less physically controversial, example: the "Rolomite".

> Rolamite is a technology for very low friction bearings developed by Sandia National Laboratories in the 1960s. It is the only elementary machine discovered in the twentieth century and can be used in various ways such as a component in switches, thermostats, valves, pumps, and clutches, among others.

> The Rolamite was invented by Sandia engineer Donald F. Wilkes and was patented on June 24, 1969. It was discovered while Wilkes was working on a miniature device to detect small changes in the inertia of a small mass. After testing an S-shaped metal foil, which he found to be unstable to support surfaces, the engineer inserted rollers into the S-shaped bends of the band, producing a mechanical assembly that has very low friction in one direction and high stiffness transversely. It became known as Rolamite.

https://en.wikipedia.org/wiki/Rolamite

Or the Hilsch-Ranque vortex tube:

> The vortex tube, also known as the Ranque-Hilsch vortex tube, is a mechanical device that separates a compressed gas into hot and cold streams. The gas emerging from the "hot" end can reach temperatures of 200 °C (392 °F), and the gas emerging from the "cold end" can reach −50 °C (−58 °F). It has no moving parts.

https://en.wikipedia.org/wiki/Vortex_tube

Now these you can actually buy. They sell little ones that go on the end of an air compressor hose to deliver "spot cold" as it's called. I once emailed a company who makes them to ask what would happen if you set it up so that the cold (or hot) output chilled (or heated) the incoming air, would you get a feedback loop? But they weren't interested.

The vortex tube is less efficient than a heat pump, so there are good reasons not to use it in every potential application, but I feel that there are good applications that go completely unrealized. That's my original point. Just because some cool technology exists doesn't guarantee that it will be used well, or at all.

"back of envelope" estimate (which you didn't actually share) "

If you are interested: going from v to 0 or going from 0 to v uniformly with acceleration in time t is related by v=at. The distance traveled is s=1/2a t^2. Plugging the first into the second gives s=1/2 v^2/a. So a=1/2 v^2/s= 1/2 (10m/s)^2/0.1m=500m/s^2~50g

Interestingly this directly follows from the definition of acceleration and doesnt use anything like Newtons laws.

Looking at the Video, why didn't they just do it in a controlled environment? Some gauges/meter marking and high speed cameras. The time it takes for the stop is in the order of t=v/a=10/500s=1/50s so only one frame in normal video rate.

Cheers for showing your work. But again, in the video, whatever it's faults, you do see a car hit a barrier and not go crunch, yeah?

> why didn't they just do it in a controlled environment?

Well, there is more than one video. The one we're talking about is obviously a public demonstration and not a scientific test. (There was one video that seems to have been removed now that showed a very good and clear demo of the ramp/glass being done at some trade show or convention. that video or others might still be on YT somewhere.)

What about that ramp/glass demo? A glass shatters when the little car thingy hits it, and then another glass doesn't shatter when the flywheel device is active.

And really, I haven't dug into this particular tech too deeply, it could well be a hoax.

But my point still stands, there are lots of interesting and useful ideas that work and get ignored or neglected. Magnus effect rotors, the Tesla turbine, desalinizing batteries, "Aircrete", etc...

I could literally go on all day, just listing the less "woo-woo" stuff off of Rex Research.

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