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New laser could cram GPS alternative into a shoebox
- master_crab 2y agoSadly, the first applications of this will most likely be military.
- ceejayoz 2y agoThis will absolutely go in missiles to handle GPS jamming and submarines where satellite signals are unavailable, yes. It'll be nice if they can get it small enough for a phone, though.
- reliablereason 2y agoI would assume that the refrigerator sized ones are definitely already in submarines.
- zardo 2y agoMaybe, but this isn't the only way to build a high performance accelerometer.
- nordsieck 2y ago> This will absolutely go in missiles to handle GPS jamming Depending on when the tech is available, preventing GPS jamming of drones is probably much more urgent in Ukraine.
- ceejayoz 2y agoYes, but until they’re autonomous the drones are still heavily subject to jamming of their radio controls. This won’t fix that. HIMARS, on the other hand, will enjoy the improvements.
- KennyBlanken 2y ago"Until"? They've been in use for years now in that war. The Shahed drone, for example, was used by Russia. About two years ago Ukraine was using autonomous drones to down Shahed drones. AI targeting came out in the Gulf war, friend. 35 years ago, Tomahawks could use rudimentary AI to match preprogrammed terrain profile and target imagery to get more precise targeting.
- ceejayoz 2y ago> The Shahed drone, for example, was used by Russia. The Shaeed is really just a rather shitty cruise missile. https://en.wikipedia.org/wiki/HESA_Shahed_136 https://en.wikipedia.org/wiki/HESA_Shahed_136 "No cameras or short-range sensors were noted in 2022." > Tomahawks could use rudimentary AI to match preprogrammed terrain profile and target imagery to get more precise targeting. Key word: preprogrammed, and similarly a cruise missile. It's the FPV drones chasing down people in trenches that require real-time video transmission to control.
- talldayo 2y agoThe Shahed drone can't use it's INS system to communicate with a ground operator or reprogram itself. As the other comment says, it's basically a glorified cruise missile that has the autonomy of a Roomba. Disabling a Shahed with another drone may have happened, but it's certainly not the primary threat to the Shahed when compared to CIWS or SAMs. AI targeting was debuted in the Patriot missile system, which does technically field the required elements of a hands-off kill chain. But TERCOM is not AI nor was it debuted in the 90s with the TLAM. The original BLOCK-I variants of the Tomohawk (and many versions released afterwards) were no more autonomous than the Shahed-136.
- aledalgrande 2y agoYeah it would be awesome to finally have accurate positioning in between highrises on the phone, gps sucks for that.
- vlovich123 2y agoThat’s literally what’s funding this research
- imoverclocked 2y agoThat could be the point of sentiment around this tech. Most funded development is done out of military R&D instead of science/consumer/art purposes. Everything else ends up benefiting eventually but it would be nice if we didn’t only create things for war and then later repurpose them for everything else.
- KennyBlanken 2y agoMore specifically, nuclear arms, where the budget is "there is no budget." Just the inertial guidance system of a 90's-era ICBM cost over six figures per missile. The ability to precisely place a missile without any external navigation (except for stars.) Once it gets cheap enough, it'll probably go into cruise missiles; it could eliminate or reduce the need for terrain contour matching, which requires radar transmission. I'm not 100% certain but I believe when MEMS accelerometers first came out, the better ones were subject to arms controls because of fears they could be used in missiles.
- littlestymaar 2y agoNuclear arms doesn't need as much accuracy as other weapons though: when using a cruise missile or a glide bomb with a few hundreds of kilograms of explosives, you need metric precision to get the military effect, when the payload is a 100kt bomb, then 100m is accurate enough. Unlike other bombs it must absolutely be 100% resilient to any kind of spoofing though, for obvious reasons, hence GNSS is a nonstarter for those when they are the default guidance system for other weapons (with backups, for cruise missile).
- dingaling 2y ago> when the payload is a 100kt bomb, then 100m is accurate enough Not accurate enough for counterforce. When a missile silo lid can withstand 600 atmospheres of overpressure, "close enough" isn't good enough.
- KennyBlanken 2y agoMy point was that nuclear missile development gets a blank check and I cited the over-six-figure intertial guidance units in 80's and 90's era missiles as an example of this. I'm not sure what point you're trying to make here? Accuracy is incredibly important because you don't put a nuke somewhere to kill people; you put it there to destroy infrastructure. More specifically nuclear missile silos, and bomb shelters (well, the people inside them.) Reducing the CEP means you can use a smaller nuclear yield to get the job done, which is preferable for a number of reasons, including politics, but also allowing for more targets in a strike. The very latest US ICBMs are suspected of having sub-100m CEP. CEP for ICBMs is "bad" enough that it is typical for planners to figure three warheads per target, but accuracy is rumored to be getting good enough where that is no longer necessary.
- horstbort 2y agoThankfully, the same measurement technique can be used to measure e.g. gravitational fields, and there are already devices available on the market which surpass classical gravimeters in accuracy and precision. There are also satellite missions in the planning to map Earth's gravitational field with atom interferometry.
- mhb 2y agoIt's only sad if you are a fan of inaccurate munitions and collateral damage.
- hi-v-rocknroll 2y agoThis is truism applicable to the vast majority of technologies. Space was once also a rival mother of invention. If quantum INS can soon take out more Russian ammo dumps in spectacular fashion, then bring on improvements to lasers.
- dangitman 2y ago[dead]
- swayvil 2y agoAn ultra sensitive motion sensor. Intriguing. Could one derive the Earth's rotation? The motion of the solar system? By watching vibrations could it be a microphone?
- thfuran 2y agoYou don't need anything nearly so fancy for a laser microphone.
- swayvil 2y agoStill want one. And this vector right here.... that's the milky way's orbit about the greater magellanic cloud...
- jacobp100 2y agoNo because velocity only makes sense as relative to something else. There’s no ‘fixed points’ in the universe This device will track acceleration rather than velocity
- roywiggins 2y agoPoints on the Earth's surface are experiencing an acceleration- after all, after 12 hours their velocity has changed direction by ~180 degrees. You can detect Earth's rotation with a sufficiently large pendulum[0] or a good gyroscope. Something with enough inertia will tend to refuse to rotate with the planet, which lets you compare the two and infer the absolute rotational speed of the planet. https://en.wikipedia.org/wiki/Foucault_pendulum https://en.wikipedia.org/wiki/Foucault_pendulum
- deleted 2y ago[deleted]
- swayvil 2y agoI figure that all motion is curved because all motion is on space bent by gravity or whatever. So motion always involves some acceleration vectors. Is that... assful?
- bee_rider 2y agoWe’ve had other discussions of these sort of quantum compass ideas, see https://news.ycombinator.com/item?id=40692333 https://news.ycombinator.com/item?id=40692333 for example. I can never quite wrap my head around it or figure out if they are all the same idea, or what, and what exactly the idea is. In particular, the article soften describe something that “could replace GPS.” But then they start taking about compasses, and things that sound a lot like IMUs. Integrating accelerations is well known as a bad way of keeping track of position over longer timescales due to catastrophic cancellation. A more accurate IMU might let you do it for a little longer, but eventually you need an absolute reference point to correct your drift. But then, sometimes there are references to making very careful measurements of the change in the gravitational field. So maybe those could act as landmarks or something? I wish there was an article for people who, like, had a control theory or signal processing class, but it was too early in the morning and not very interesting.
- gmrple 2y agoGravity map matching is an approach that can provide absolute references, the general problem there is that gravity maps are not good enough.
- bee_rider 2y agoThey also vary over time or something, right? So even a more precise measurement device, to get better gravity maps, doesn’t solve the problem… maybe? This is all based on half-remembered other comments.
- ck2 2y agoI wonder if we are within a century of having pulsar detection on a chip. Document enough millisecond pulsars and find your position anywhere in the galaxy. When signal reception and computing power get powerful enough, put it on your wrist.
- xandrius 2y agoProblem is always going to be power rather than computation. I still haven't heard of any major breakthrough in the size of our batteries but when that comes we'll be miniaturizing literally anything.
- ck2 2y agoWe already have solar self-charging watches, power sources by then will also be micro kinetic generators, room temperature vs body temperature generators, and even pulling power from all the radio signals in the room like 5ghz, etc. Maybe they will even use some kind of super capacitors instead of batteries.
- ajuc 2y agoThe main application would obviously be missiles and autonomous military drones. If you can use GPS - you should. It's crazy cheap and it doesn't accumulate errors over time. But in a war GPS can be jammed. This can't.
- 2OEH8eoCRo0 2y agoLot's of Western weapons already combine INS and GPS. I suppose this could be a better alternative to INS. https://en.wikipedia.org/wiki/AGM-158_JASSM https://en.wikipedia.org/wiki/AGM-158_JASSM > Guidance system: GPS, INS, IIR
- wood_spirit 2y agoThere was a big cheapening when the military miniaturised fast gps so small and cheap it could be put into artillery shells. This was very effective when Excalibur and himars first arrived in Ukraine. By the time the small diameter bombs had been married to a rocket the Russians had effective and pervasive gps jamming and accuracy plummeted. The older more expensive systems with ins like atacms maintained accuracy.
- ajuc 2y agoThere's a Polish guy that volunteered in Ukraine building drones, he talked about this. There are tricks to avoid most of the GPS jamming, long-distance drones use them (he said the evolution is crazy fast, every 3 months there's new techniques deployed) the traditional military systems can't be modified in 3 months so they are more vulnurable. They are constantly changing the video and controlling frequencies, there is some AI appearing, a big change was flying signal repeaters, there are tethered flying drones with rolls of fibre for steering/video that are completely invulnurable to jamming. Often they also have cables for power, so they can stay in air forever. But even in the cheapest drones there are ways to deal with it. For starters you shield the GPS from the bottom half-sphere, and you put 2 GPS receivers at opposite ends of the drone and compare the signals. Jammers are closer than sattelites, so the difference between the signals sampled 2 meters apart will be mostly the jamming, and then you can remove it. It's not perfect, but it's good enough for the drones to hit the targets most of the time. And they obviously have cheap accelerometers, compass etc - which is basically INS, just less accurate. So it's sufficient to get by through the region with jamming, and to recognize when GPS is spoofed.
- fdfgyu 2y agoShips are big, if this were a real problem it would be easy to find space for a "lab sized" laser. ICBM warheads are small. Space in drones and fighter jets is at a premium. This is military.
- bluGill 2y agoWhile ships are big, there is a lot they want in them so space tends to be limited if the ship wasn't designed to do that. Military places the big things and the rest in between
- ttul 2y agoIf Sandia is revealing this, they probably have a secret version that is already being loaded into cruise missiles and ICBMs. Seeing what’s happening over in Ukraine, it has to be clear to every military in the world that GPS is no longer of much practical use on its own.
- cyberax 2y agoICBMs have never relied on GPS. They were always using inertial navigation, sometimes coupled with astronavigation.
- jandrewrogers 2y agoUS military systems have always been based primarily on inertial guidance as a matter of policy. They may take optional GPS corrections for small improvements in precision but they don't rely on them. GPS was never really designed to be a navigation system, even though you can use it for that; the military designed it to be a measurement system. The Soviets could have destroyed it the day it was built, it was strictly a peacetime tool. Also, what gets exported to Ukraine is intentionally downgraded in many cases, at least from the US side. Much of what they receive was state-of-the-art circa 1990s or earlier.
- ttul 2y agoYes, for sure intertial and star guidance has been in use in ICBMs forever. But if the inertial guidance is far more accurate, perhaps this changes what you can do with conventional ICBM munitions. For instance being able to target something 10,000 miles away in a GPS-denied place with a 2,000 pound chemical explosive rather than using a cruise missile. Now you can take out someone’s leadership from US soil without using a nuclear warhead.
- ttul 2y ago… acknowledge all the problems with launching an ICBM and the adversary not knowing what type of warhead it carries, of course… just ignore me.
- krick 2y agoSo, remembering the exact location once, and then tracking all movement with almost absolute precision, thus calculating all future locations? Did I get it right?
- actinium226 2y agoBasically yes. If you want to get technical about it, it's not tracking movement it's tracking acceleration, which you can then integrate twice to update position.
- krick 2y agoTechnically, acceleration is movement in an inertial system... Anyway, I was wondering for a long time, why phones/watched don't attempt to do it (at least, I never saw useful results of it). Surely it would be more useful to me than nothing, when lost in a labyrinth underground. I always assumed, that results are so horrible (close to random) that nobody even bothers. But then it doesn't tell me much if there is an accelerometer 1000 or 1M times more accurate, in a shoe-box or otherwise. Like, how often does it have to re-calibrate after all? Are there any records of how currently available consumer devices measure up in this regard?
- mhb 2y agoAfter integrating the output twice from current COTS accelerometers, position is useless in at most a few minutes.
- sahmeepee 2y agoYou might be interested in this app to try it for yourself: https://github.com/nisargnp/DeadReckoning https://github.com/nisargnp/DeadReckoning I read a paper some time ago which suggested that mobile devices are still nowhere near good enough to use this e.g. for navigation around a shopping mall.
- kylehotchkiss 2y agoBut like an IMU, doesn’t this need occasional calibration with a known location source?
- cryptonector 2y agoYes, but if it's accurate enough then the frequency of recalibration can be kept low enough that inertial navigation can be practical.
- golemiprague 2y ago[dead]
- cyberax 2y agoAnother obvious idea: use mega-constellations. GPS signals can't be signed because the signal bandwidth is limited, a digital signature is going to take hours to get transmitted. But by using something like a Starlink satellite, it's possible to transmit digitally signed timing packets that can't be spoofed.
- minetest2048 2y agoGalileo open signals are signed: https://www.gsc-europa.eu/galileo/services/galileo-open-service-navigation-message-authentication-osnma https://www.gsc-europa.eu/galileo/services/galileo-open-serv... and it have the same data throughput as GPS L1
- night862 2y agoIt’s a newer development, GPS proper doesn’t support signing. Galileo is a different satellite.
- cyberax 2y agoIt takes about 5 minutes to transmit a signature, as I understand? The receiver then can try to find the combination of navigation packets that gives the right signature, and recover its position this way. So yeah, this should solve the spoofing issues for most cases. Low-orbit sats would be able to transmit a signature every millisecond or so, but that's not really necessary.
- Havoc 2y agoReally hope they hurry with this. Would solve a fair few issues