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Indian startup 3D prints rocket engine in 72 hours

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Re: Indian startup 3D prints rocket engine in 72 hours

#211

Post by mynameisvlad »

ETH_start wrote: post #154
toss1 wrote: post #121

Earlier quoted context omitted.

This is true, but it also falsifies Tesla's naming, promotion, abd advertising of the capability as "Full Self-Driving". ("Self-Driving" alone could be reasonable in certain contexts, but insisting on "Full Self-Driving" is a flat-out lie in plain language. Saying " Alan is fully capable of driving the car." means that he requires zero monitoring and/or intervention; same for the "Fully..." phrase.)

What the name implies if interpreted without any context pales in comparison to the repeated and explicit instructions and warnings given to the driver that clarify that the driver should always be in control.

You don’t just get a pass, especially not when you actively are promoting it as soon™ being able to drive you without any input whatsoever. Robotaxis and the like have been promised for years now, it’s not like Tesla isn’t actively claiming the technology is basically around the corner.

In short, saying it’s “Full Self Driving (Supervised)” is not really enough.

Re: Indian startup 3D prints rocket engine in 72 hours

#212

Post by sobellian »

vasco wrote: post #171
sobellian wrote: post #141

Earlier quoted context omitted.

This is a "truthy" statement that sounds right but is, in fact, false. Radio systems have an easily measurable SNR, but the noise cannot be eliminated.

You can measure is from outside the system itself if you know the original signal. Of course its possible to measure the noise externally if you know what was transmitted.

AFAIK this is incorrect. There exist modulation schemes where the received signal power is evident. For Wifi the signal is usually > 10-100x the noise floor and it is modulated with phase-shift keying. So there is no technical problem with seeing a noise floor, then receiving a much larger signal with constant envelope and calculating an SNR.

ETA: Just to sharpen the point, this is clearest when considering digital noise and error correction. It is easier for error correction codes to indicate a corrupted message than it is to provide the correct message.

Re: Indian startup 3D prints rocket engine in 72 hours

#214

Post by Etheryte »

treflop wrote: post #210
sandworm101 wrote: post #142

Earlier quoted context omitted.

>> maybe the juice isn't worth the squeeze In rockets/aerospace, where the failure of any one of a thousand different parts means instant disintegration, checks are always worth the squeeze. Everyone talks about building rockets on the cheap and accepting a slightly-higher failure rate, but in reality that doesn't work. Even a tiny increase in component fault rates translates to total mission failure once multiplied…

My dad works in aerospace. In no field or world does anyone actually check every little part. You create a process, you test that process so that you understand its limits, and then you make sure to follow that process. Now I don't know if 3D printing rocket parts actually works and I have my doubts but this startup is currently testing the process and they will figure out its limits. That's the whole point of R&D.

For context, 3D printing rocket parts is incredibly common, even student teams often use printed nozzles and such. The linked article is about printing a whole engine as a single piece, which is a different beast.

Re: Indian startup 3D prints rocket engine in 72 hours

#216

Post by hermitcrab »

gridspy wrote: post #196
nvy wrote: post #135

Earlier quoted context omitted.

The "Wright Brothers" moment for rocketry happened 60 years ago.

The first useful rockets were during the second world war, used for artillery into London. So over 80 years ago. https://en.wikipedia.org/wiki/V-2_rocket

Depends what you mean by 'useful'. They were a technological marvel, but an incredibly inefficient way to deliver approx a ton of high explosive. But I guess we should be thankful that Hitler wasted so much of Germany's increasingly scarce resources on 'Wunderwaffe' like rockets. The Allies developed technology that was less showy, but much more useful (computers, cavity magnetron, proximity fuze, atom bomb etc).

Re: Indian startup 3D prints rocket engine in 72 hours

#217

Post by nvy »

gridspy wrote: post #196
nvy wrote: post #135

Earlier quoted context omitted.

The "Wright Brothers" moment for rocketry happened 60 years ago.

The first useful rockets were during the second world war, used for artillery into London. So over 80 years ago. https://en.wikipedia.org/wiki/V-2_rocket

Yeah I was referring to Sputnik, as the V2 wasn't orbital.

Re: Indian startup 3D prints rocket engine in 72 hours

#218

Post by Dylan16807 »

lesuorac wrote: post #163
lukan wrote: post #144

Earlier quoted context omitted.

Is there data, that indicates Tesla did this, or something like this?

Kind of? Autopilot has a habit of disengaging right before crashes [1]; which may not be a bad thing, your seat belt also has a habit of not being adjustable in a crash (dunno if an ICE engine will turn off). Mix that with Elon had a habit of commenting on crashes [2] to keep good marketing about FSD. And like who cares if it was "Auto lane control" vs "Autopilot" that let somebody drive the car from the passenger se…

Your second link makes it clear that no version of self-driving was on anywhere near that particular crash, so that does not support the above comment at all.

If the only true part is that the system disengages at some point, then "kind of" is much too generous for that kind of rumor-mongering.

But if I ever see some real proof I'll spread it far and wide.

Re: Indian startup 3D prints rocket engine in 72 hours

#219

Post by abduhl »

gridspy wrote: post #203
abduhl wrote: post #198

Earlier quoted context omitted.

And you think that a driver commands their Tesla to run into an object when they enable autopilot or FSD?

One is a failure to act as an agent - to control the car and make decisions. Another is a failure to even be a reliable tool - to do what the operator commands. Very different. Creating Agents is a lot harder.

Coming up with new words and terms in order to escape the comparison smacks of This Time It’s Different. Therac-25 was an Agent for performing radiation therapy - it controlled the radiation machine and made decisions. Autopilot/FSD is supposed to be a tool for the driver and it fails to be a reliable tool by driving into things.

This Time It’s Not Different At All

Re: Indian startup 3D prints rocket engine in 72 hours

#220

Post by Dylan16807 »

vasco wrote: post #49
Etheryte wrote: post #26

> The machine also automatically outputs a report that details any deviations during printing, removing the need for postfabrication qualification. Anyone who's previously worked with 3D printing knows that this simply does not pass any kind of a sniff test. Both preventing and detecting internal defects is one of the, if not the hardest problem in 3D printing. There are many large companies trying to find ways to re…

If any system could measure its own signal to noise accurately, it wouldn't have any noise in the first place.

That only works if you have an ultra-high-resolution record of isolated noise.

An accurate measurement of signal-to-noise is just some power levels and basic knowledge of the shapes of the signals. It's easy to figure out and doesn't help you read back your data. It helps you configure appropriate transmission settings and doesn't do much else.

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