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Vaccum-chamber quantum sensor device could allow GPS-free navigation

breakingdefense.com

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Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#61

Post by nuccy »

avsteele wrote: post #25

The innovation here appear to be the chamber. (caveat: I still need to read the paper). A few thoughts follow. They are going for a UHV***, probably Still a lot of other work to do though. I see a table full of optics to make the MOT*. Also see a pair of anti-Helmholtz coils for the magnetic field. They could maybe replace those coils (which probably drive a few amps) with permanent magnets (assuming they don't need…

> Quantum sensors for PNT use atomic accelerometers or gyroscopes

There is one fundamental problem with using any sensors for global positioning: a stationary frame of reference is indistinguishable from the one moving with a constant speed on a straight (actually geodesic [2]) line (inertial frame of reference, general principle of relativity [1]). So accelerometers and gyros indeed can give you accurate orientation and acceleration/deceleration data, but they will inevitably accumulate uncertainty for long eventless movements, so use of GPS will be needed to occasionally calibrate the true position. The obvious options is to augment this data with readings of wheels rotational, airspeed sensors, radars, etc, then such systems may last even longer without cross-calibration with GPS.

1. https://en.m.wikipedia.org/wiki/Principle_of_relativity

2. https://en.m.wikipedia.org/wiki/Geodesics_in_general_relativ...

Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#62

Post by jiggawatts »

JohnJamesRambo wrote: post #28
chana_masala wrote: post #27

Earlier quoted context omitted.

HackerNews amazes me with how for nearly any topic there will be deep expertise in the thread. Thank you for sharing

But then it also usually impresses me with how people think companies haven’t thought of and tried the things they thought of in reading the article and thinking about it for a few minutes.

But sometimes they haven't thought of "it".

These forums have an interesting kind of collective intelligence. People commenting here rarely (if ever) have full knowledge of the specifics of the particular instance of the topic at hand, but often have very deep knowledge of the associated theory.

In my experience, if you take any 10 people and form a team or company to make some product, they won't have anywhere near the breath or depth of knowledge that people here could bring to bear. What they have is time and persistence, but I guarantee you that they're "flailing about" and wasting time on many wrong or suboptimal solutions. In most cases, someone here could set them on the right track within minutes.

It's so strange to me that the Internet enables this, but we use this superpower for essentially nothing more than casual chit-chat. We show off our knowledge, where we happen to have a particularly impactful trick up our sleeve, win some meaningless points, and feel smug about ourselves for an afternoon. I do this all the time. It's fun.

But what would happen if we did this properly? Like Uber? Made it into an app where startups, research teams, and software developer houses could use the collective knowledge and advice of hundreds of thousands of people instead of just the dozens on their staff? Just click here to get expert advice on your question, $55 guaranteed price? Would you click?

Maybe it is time that we all plugged into the group consciousness and started contributing to the collective... /s

Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#63

Post by MauranKilom »

jiggawatts wrote: post #62
JohnJamesRambo wrote: post #28

Earlier quoted context omitted.

But then it also usually impresses me with how people think companies haven’t thought of and tried the things they thought of in reading the article and thinking about it for a few minutes.

But sometimes they haven't thought of "it". These forums have an interesting kind of collective intelligence. People commenting here rarely (if ever) have full knowledge of the specifics of the particular instance of the topic at hand, but often have very deep knowledge of the associated theory. In my experience, if you take any 10 people and form a team or company to make some product, they won't have anywhere near…

To some extent, that's just StackOverflow (and the other StackExchange sites). Not quite as commercially focused as you imagine, but at least the code parts definitely are used like that.

For more individualized problem solving, this just amounts to consultancies, no?

Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#64

Post by a_e_k »

brabel wrote: post #60
chana_masala wrote: post #27

Earlier quoted context omitted.

HackerNews amazes me with how for nearly any topic there will be deep expertise in the thread. Thank you for sharing

The OP seems to know something, but I wouldn't go as far as taking the comment above as coming from an "expert"... the fact they feel confident to make recommendations about improvements on the chamber without even reading the paper actually tells me they are just armchair expert.

I don't know about that. At least for myself, when I say that I've read a paper I mean that I've read it thoroughly from end-to-end and thought deeply about it, not unlike what I do when I'm doing a peer review. (I.e., "grokking" the paper.)

There are way too many papers to do that for every one that comes out in my field, though, so I've gotten pretty good at skimming a paper quickly and making a snap assessment. I might say I'm aware of or acquainted with said paper, but I'd never say I'd really _read_ it.

So charitably speaking, I'd interpret the top-level commenter (avsteele) as meaning that they've only skimmed the paper and these are off-the-cuff comments, rather than that they haven't looked at the paper at all.

Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#65

Post by baq »

willis936 wrote: post #38
Animats wrote: post #36

DARPA has been funding work on better gyros and accelerometers for about 10 years now. MEMS gyros keep getting better. The good ones are down to a few degrees per hour.[1] That IMU/GPS is $3,386.09. Not down to the phone/vacuum cleaner price point yet. This is nowhere near as good as the device described in the parent article, but it's good enough for a lot of applications. If you can get a GPS fix every few minutes,…

GPS is trivial to jam. Any exotic IMU has huge defense implications. Being able to miniaturize it would be a big deal.

Civilian GPS. Milspec encrypted FHSS or whatever are they using not so much unless you flood the whole spectrum.

Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#66

Post by basicplus2 »

sgtnoodle wrote: post #57
basicplus2 wrote: post #49

This reminds me of a spacecraft navigation system that employed an almost perfect sphere, that floated inside the centre of chamber that employed a detection system that corrected the spacecrafts direction to keep the sphere in the centre of the chamber. On the drawings it was referred to as the space crafts "consciousness" Unfortunately i cannot find any reference to it anywhere.

I remember that too. Maybe this? https://en.m.wikipedia.org/wiki/Gravity_Probe_B

Thats cool! but not that.. the one I an thinking of used the device for course correction over vast distances

Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#67

Post by willis936 »

Johnythree wrote: post #55
jvanderbot wrote: post #52

Earlier quoted context omitted.

That's great for radios, but I wasn't aware GPS satellites employed this technology in their transmitted beacons.

GPS does use Spread Spectrum for its navigation beacons.

SSC does next to nothing for jamming. It changes the band by a negligible amount.

Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#68

Post by musingsole »

JohnJamesRambo wrote: post #28
chana_masala wrote: post #27

Earlier quoted context omitted.

HackerNews amazes me with how for nearly any topic there will be deep expertise in the thread. Thank you for sharing

But then it also usually impresses me with how people think companies haven’t thought of and tried the things they thought of in reading the article and thinking about it for a few minutes.

We're talking about quantum mechanics and vacuum chambers. If you can spec such a system... congratulations, you're an expert. Kathy down the street doesn't even know this technology exists.

On patents...if you're in a sufficiently unexplored space, simple ideas become eminently patentable. So -- given the context -- yeah, pretty much any thought made that is aware of these systems is likely patentable.

Profitable to patent? That's a different question.

Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#69

Post by horstbort »

avsteele wrote: post #25

The innovation here appear to be the chamber. (caveat: I still need to read the paper). A few thoughts follow. They are going for a UHV***, probably Still a lot of other work to do though. I see a table full of optics to make the MOT*. Also see a pair of anti-Helmholtz coils for the magnetic field. They could maybe replace those coils (which probably drive a few amps) with permanent magnets (assuming they don't need…

Permanent magnets are typically a no-go, because these sensors employ matter-wave interferometry, i.e. interference between atoms. Those unfortunately do not only react to gravity, but also to magnet fields, so these need to be suppressed as far as possible, especially gradients. And yes, this will absolutely be a pulsed design. I think, the breakthrough here is that they maintain a decent vacuum even without NEGs, which you can of course buy off the shelf, but they still tend to be quite bulky. Also, they state a vacuum of about 10^{-7} torr. Far from UHV.

Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#70

Post by jaclaz »

jiggawatts wrote: post #62
JohnJamesRambo wrote: post #28

Earlier quoted context omitted.

But then it also usually impresses me with how people think companies haven’t thought of and tried the things they thought of in reading the article and thinking about it for a few minutes.

But sometimes they haven't thought of "it". These forums have an interesting kind of collective intelligence. People commenting here rarely (if ever) have full knowledge of the specifics of the particular instance of the topic at hand, but often have very deep knowledge of the associated theory. In my experience, if you take any 10 people and form a team or company to make some product, they won't have anywhere near…

>Made it into an app where startups, research teams, and software developer houses could use the collective knowledge and advice of hundreds of thousands of people instead of just the dozens on their staff?

Maybe it would be needed that those (startup, research teams, software developer houses) learn before to listen to their customers/users.

Everyone of course is different and has different experiences, but in the last few years (personally) I found an increasing "detachment" between the people that write the software and their users.

Maybe it us just me, but it seems like users (even paying ones in case of commercial tools) are considered more a nuisance than a resource.

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