Designers Release 'Aweigh', An Open Source Alternative to GPS (dezeen.com) 186
"A team of student designers and engineers from the RCA and Imperial College have designed an open-source alternative to GPS, called Aweigh, that does not rely on satellites," reports the design magazine Dezeen.
It's similar to the sextant, calculating positions by measuring the angular distances between the horizon and the sun. ExRex (Slashdot reader #47,177) shares their report: They said that Aweigh can even work on a cloudy day when the sun is not in view, and unlike devices that use satellites, such as smartphones, Aweigh functions offline so a user's positional data cannot be leaked through the internet.
"Satellites send information which can be intercepted and interfered with, but to interfere with Aweigh, one would need to artificially move the sun," explained the team of four, made up of States Lee, Samuel Iliffe, Flora Weil and Keren Zhang. "If one of the devices is faulty or broken, it is only that user who suffers. If one satellite is faulty, then the consequences can affect millions of users.
"Most people don't think about the way they navigate," the group continued, "but as concerns over centralised technology and data privacy increase, individuals should have a choice over how their data is taken and used. Aweigh is about giving back choice...." Describing the system as "a set of tools and blueprints", the team wanted users to be able to hack or fix the tools they use, so making the project open-source was important.
There's a video about the device here. It locates the sun by reading light values with a customized Raspberry Pi board.
Although Slashdot reader RockDoctor asks an interesting question: does it work at night?
It's similar to the sextant, calculating positions by measuring the angular distances between the horizon and the sun. ExRex (Slashdot reader #47,177) shares their report: They said that Aweigh can even work on a cloudy day when the sun is not in view, and unlike devices that use satellites, such as smartphones, Aweigh functions offline so a user's positional data cannot be leaked through the internet.
"Satellites send information which can be intercepted and interfered with, but to interfere with Aweigh, one would need to artificially move the sun," explained the team of four, made up of States Lee, Samuel Iliffe, Flora Weil and Keren Zhang. "If one of the devices is faulty or broken, it is only that user who suffers. If one satellite is faulty, then the consequences can affect millions of users.
"Most people don't think about the way they navigate," the group continued, "but as concerns over centralised technology and data privacy increase, individuals should have a choice over how their data is taken and used. Aweigh is about giving back choice...." Describing the system as "a set of tools and blueprints", the team wanted users to be able to hack or fix the tools they use, so making the project open-source was important.
There's a video about the device here. It locates the sun by reading light values with a customized Raspberry Pi board.
Although Slashdot reader RockDoctor asks an interesting question: does it work at night?
Eh? (Score:5, Insightful)
What? GPS is one-way and doesn't need the Internet to function at all.
Re: Eh? (Score:2)
The kids today think that because your cell phone is dumb and refuses to give gps readings if it doesnâ(TM)t have live ephemeris, all gps is like that.
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I encourage people to read up on the GPS satellite system. It's designed from the ground up to be standalone. Any use of Internet resources is just an enhancement of GPS; for instance you can have the equivalent of DGPS (Differential GPS, a way of improving accuracy dramatically) by using Internet resources. But otherwise a GPS receiver can function with nothing other than it's own antenna.
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you can have the equivalent of DGPS (Differential GPS, a way of improving accuracy dramatically) by using Internet resources
I've actually *done this* before. Please read every word before replying, mmkay?
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Provided your device has all the maps built in. Otherwise you have a bunch of accurate clock signals and some math problems to work out.
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My Win7 phone had 'Here', which offered downloadable maps. I downloaded the maps for the US states I expected to be in, and also for some European countries I drove in. The maps were free, and I had plenty of room for them. So this much at least is easy. And afaik, it would have been possible to use it in a phone that had no cell provider, once you installed the maps. That's certainly how I used it in Europe--I didn't bother to buy a European sim card. So there would have been no return signal, assumi
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Ummm... for the most part yes, your phone is most definitely giving away your gps location data.
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Osmand supports both online and offline maps.
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So does Google maps.
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Sounds interesting. I may have to check that out.
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Last time I was in the Amazon or the Andes, there was no construction or traffic. (Ok, there was traffic in Quito and Bogota, but not elsewhere in the Andes.) Landmarks, yes, but most maps have those.
All seriousness aside, while the sidewalk may stop once you get outside of New York city, there are plenty of downloadable open-source maps + gazetteers for the rest of the world, and they show significant detail. Here's a map of Logrono (the 'n' should have a tilde, but this is slashdot), Ecuador, a town ou
WTF (Score:5, Insightful)
"unlike devices that use satellites, such as smartphones, Aweigh functions offline so a user's positional data cannot be leaked through the internet"
GPS doesn't use the internet at all. It is a one-way transmission from satellite to Earth based stations (such as the sensor in the phone), and uses triangulation of multiple signals to determine position. There is nothing internet about this at all.
Cell phones OPTIONALLY have A-GPS, which also uses Wi-Fi and Cell Towers for triangulation, which relies upon centralized databases accessed over the internet, but this is purely optional!
Re: WTF (Score:3, Interesting)
Is this a gofundme scam? Everything seems wrong.
Why no ground-based beacons? (Score:2)
The "interesting" mod caught my attention, but it turned out to be an AC, so I'm not going to reply along that line. WTF you ACs, eh?
However I wish there were more interesting, dare I say insightful, comments to be found. Yeah, it's early as measured by Slashdot-front-page time (I'd estimate about 1/16 o'clock), but I'm still disappointed. Maybe it's an intrinsically confusing topic? Security is one aspect. The linkage to personal information seems spurious, except that this "Aweigh" app might well be a phi
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but I still don't understand why no one is producing cheap little GPS transmitter units for indoor use.
Because people with suits and guns will show up and take all your toys away. All your toys, not just your illegal transmitters. And worse, they'll take you away, too.
You'll need to come up with a plan that involves unregulated bandwidth. And then triangulate using that, instead of triangulating using GPS frequencies. You could probably just use wifi.
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I think in your rude way you are trying to say you think (or theorize or fantasize) that the frequency conflicts cannot be resolved. You seem to lack any technical justification, though it's possible it exists (even though your presentation was utterly unpersuasive). It's obvious that GPS is designed to deal with lots of transmitters as satellites become more or less visible, and there must be technical limits to how many signals can be handled at one time by one receiver.
Of course I'm strongly biased again
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I think in your rude way you are trying to say you think (or theorize or fantasize) that the frequency conflicts cannot be resolved.
Oh, I'm being rude, well. Fuck you.
And no, I don't think the conflicts can't be resolved, I think those conflicts can't be resolved by you. Or by any other individual party. Multiple industries would have to agree it is a good idea, just to get to the state where the US military tells you "No." It isn't that that part "can't" also be resolved, it is that it "hasn't" been resolved, so nobody is going to try to build the device you describe. You don't even build a prototype of that unless you're a licensed go
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Or like loran, invented during WWII.
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Everything you need to know can be summed up by this one phrase from the article:
Royal College of Art
It's a neat hack, I'll grant. An electronic sextant, with software and 3D models for printing. It'd be a fun build, educational, and perhaps even useful. But forget all that stuff about how it corrects deficiencies of GPS. That's all nonsense which I hope was written with tongues firmly implanted in cheeks. It's an art project.
Re:WTF (Score:5, Insightful)
Yeah this makes zero sense. It require accurate time to function. Guess what you need to get an accurate clock? An existing accurate clock, so you either need to use the internet to get an updated time or you can just access the GPS clocks. But if you access the GPS clocks then you're using evil satellites.
And in order to calibrate your compass, you again need to consult existing up-to-date maps which again requires connections to the outside world.
It is a fun science project but it's nothing more than that. It doesn't actually give the user any sort of independence.
You know what's way more useful if you need to navigate? A topographical map and a compass. Easier to assemble too and doesn't require recharging.
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getting time or GPS from satellites doesn't involve your phone talking to anything.
even without update the clock in your cell phone will not lose a second in a week, will lose less than 20 seconds in a year!
the problem is the accuracy of determining position of sun, a quality sextant in proper hands will go to tenth of nautical mile under ideal conditions but this method sure won't! so if you're camping and want to know within about a mile where you are maybe this method would work (and there are no trees
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It also can download the ephemeris data for a faster fix.
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GPS doesn't require the internet but it doesn't function offline. You are dependent on a satellite network and cell phone triangulation depends on the cellular network. This solution would be offline in the sense that it doesn't need any external network. Cell phones have GPS and A-GPS and using that for your benefit is optional, this data is definitely generated and tracked under the justification that it is needed for emergency services to function.
I get the sense that whoever made that video knows and un
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Incorrect.
A-GPS is assisted GPS, and ALL cellphones must have them as part of the E911 mandate. What happens is it allows GPS location with only 1 GPS satellite in view, using the difference in received signals and what the tower gets to determine the phone's location.
It also allows sending the ephermeris data via the cont
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GPS doesn't use the internet at all. It is a one-way transmission from satellite to Earth based stations (such as the sensor in the phone), and uses triangulation of multiple signals to determine position. There is nothing internet about this at all. 100% of smartphones in the US feed the location back to the cell provider and Google and Apple. Technically, the GPS doesn't do it, but if you're using GPS on a cellphone, everybody that you're giving your data to knows exactly where you are.
Turn on airplane mode. If you have offline map software (TomTom for example) or just use a GPS utility that shows the coordinates and altitude, they work just fine. If you want completely offline never online, get a dedicated GPS device and load maps over sd card.
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get a dedicated GPS device and load maps over sd card.
This has the added benefit of actually telling you what your latitude/longitude means. :D
Without a map, your lat\long doesn't tell you how to get to your destination.
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get a dedicated GPS device and load maps over sd card.
This has the added benefit of actually telling you what your latitude/longitude means. :D
Without a map, your lat\long doesn't tell you how to get to your destination.
There are several offline GPS options available on smart phones. Tom Tom has one for example. If you bought the old one, you're in even better shape since it was a one-time purchase app.
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I meant vs a glorified sextant.
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Lol. The concept works only at night (Score:2)
> No need for a map light since it won't work at night anyway, so saves some space that way too.
That's funny.
That reminds me, the method claimed I the summary - measuring the angle between the sun and the horizon, only tells you your latitude. It doesn't tell you your longitude. The sun, in particular isn't even very precise for latitude because it's so big.
To get longitude and latitude, you need at least two celestial objects, and preferably more. Preferably points of light - stars. So the sextant only
Re: WTF (Score:2)
It does if you know the coordinates of your destination.
You probably use that DNS thing too, donâ(TM)t you?
Re:WTF (Score:5, Informative)
Multiple times, both Google and Apple have been caught (and I think Google still does) storing your location data on your phone, until you go back online.
Of course, this could still happen with the above app/idea. The real issue here is that Google has root on your phone, just so you can install a couple of apps. Same for Apple. They own your phone, because Samsung/LG/whatever gave them the keys -- and that includes the keys to the phone's modem firmware usually...
(Via some API or another)
Anyhow.
Bah.
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Agreed. I'll sell Blymie one of my old cell phones with GPS maps pre-installed. He need never put a functioning sim card in it.
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You aren't offline, you are still dependent on the GPS network. The video was produced by a college of art, I don't think it was produced by someone who actually understood the solution or technology at all.
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Right, or take your sim card out. I've used GPS on my old Win7 phone in Europe, where my US-based sim card was of no use. The GPS, and my downloaded maps, worked just fine.
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100% of smartphones in the US feed the location back to the cell provider and Google and Apple.
I have an android phone without GPS malware (Google Play Services). I use GPS (Global Positioning Systems) for maps completely offline and it doesn't transmit GPS location data to anyone.
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That's a function of how cell phones work so that the best cell tower* can handle the any calls or data. As you move around your location is sent to the nearby towers and the tower that handles your phone can change. (It's a simplistic overview.) It has nothing to do with how GPS works.
* - I say tower but the telecom equipment could be mounted on any type of structure.
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That is the question. How does it operate? People are jumping up to attack the solution... that seems premature given that nothing in the TFA or video gives any real indication of how it works.
Ephemeris (Score:2)
Satellite ephemeris data is part of the signal from the satellites (the other part is the phase matched carrier wave.) If your phone is going to the towers it is either triangulating from them or it is pulling map data (or potentially sending your current location to somebody.)
Here's the problem (Score:2)
Ephemeris data is literally the exact current location of the satellite. There's no point in downloading ephemeris data ahead of time, because as soon as you can see the satellite it is going to broadcast its data to you. If there is an orbital correction or position re-measurement, all of that stored data would be obsolete. Only the latest transmission is going to useful.
GPS transmits two primary data, the ephemeris and the phased carrier wave. The ephemeris transmission gives the current exact positio
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"this post wound up WAY longer than I expected. Sorry." I'm not, I learned. Thank you.
Open source solution already exists (Score:2)
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Good maps are not "open source."
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Good maps are not "open source."
There are some pretty good open source maps, actually. There's loads of free (and freely redistributable) GIS data out there.
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The base map source I've found is OpenStreetMap. It's data, not software, but it is open in the sense that it's all public, you may download it and use it for whatever purpose, and is not locked up behind Google's style of walled garden. It also has reams of data not available in Google's mapping services, such as the best map of trail networks I've found.
Go ahead, try to batch-download all of Google's map data. Let us know how that goes for you.
So unless you want to quibble over the meaning of "open sou
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Good maps are not "open source."
Welcome to the surface!
No, those are not mutants.
So basically worse than anything else? (Score:2)
Great, even a last cell + accelerometer set-up will do better. And it will be pretty bad.
It doesn't seem to be precise enough to be usefull (Score:2)
However people have demonstrated that with a simple photocell and a microcontroller with a real time clock, you can kinda get a rough estimate of where you are. The trick is to compare the brightness outside with the current time and date in UTC. Essentially you estimate dawn and sunset and can use that to determine local time and season.
Of course with more effort you could take the position of the sun into account. You can measure that, for example via polarisation. In any case, it's fairly inaccurate, but
Punch that strawman right in the nose. (Score:2)
No, "devices that use [GNSS] satellites" do not have to be online, or leak info. Even smartphones (the GPS on a deactivated, disconnected smartphone can still work, it may just take longer to lock on, because it's not getting aGPS info).
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The point isn't that the device "has to" be online. The point is that the device is in fact online, that the devices tend to leak information, and that users often lack control of that process.
There are other ways to solve the problem, to be sure. But just because a use case doesn't apply to you, doesn't imply it is somehow wrong.
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Does it fit in my pocket? (Score:2)
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Also, as someone else said, "Does it work at night?"
Yes, all you need to do is walk east until you see the sun then it will start working again. Alternately you can walk briskly north or south until you get to the other side of the planet, or run west to catch up to the sun.
needs technical details, not stop-motion showboat (Score:4, Insightful)
Electronic sextant (Score:3)
The problem is that it needs an accurate time to get a (more) accurate reading, hence you'll need to query an NTP server (or attach a GPS-based clock), you just destroyed your entire premise of staying offline and not requiring a GPS signal.
It's a cool high school science project though, but I wouldn't say it's something that will ever be a commercial success. We need GPS for very precise and accurate navigation, especially in air- and waterways.
At night you could navigate with the stars, not sure if they radiate quite enough signal to be measurable here on earth through a cloud canopy.
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The problem is that it needs an accurate time to get a (more) accurate reading, hence you'll need to query an NTP server (or attach a GPS-based clock), you just destroyed your entire premise of staying offline and not requiring a GPS signal.
While probably overkill there are always CSACs if you need them.
https://www.microsemi.com/prod... [microsemi.com]
Personally given over reliance on GPS and lack of or extremely rusty manual navigation skills something like this would be a good backup. Either due to technical fuckups or intentional acts (Such as North Korea denying GPS over thousands of square miles of ocean) automated star nav like this as backup to GPS would be useful given cost.
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I could use a 555 to build a clock with better accuracy than the clocks they had on ships when sextants were popular, so I think people are wildly misunderstanding the precision when considering that it needs an "accurate" clock to get an "accurate" reading.
The reason that it wouldn't be a "commercial success" is that the whole use case is to avoid one of the ills of the modern consumerist landscape.
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I'm not sure what you're replying to, but at least back in the 70s, there were radio broadcasts that would let you set a chronometer to be precise to within 1/5 of a second. (By precise, I mean the chronometer might be a half hour off, but you knew exactly how far off it was to within 1/5 second.) I don't know whether those time signals are still broadcast.
who will use this? (Score:2)
Will it work for vampires (Score:2)
Asking for a friend, of course
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There is no reason not to make one that uses the moon.
So it should work for werewolves, too.
Any tech specs? (Score:2)
Did anyone find an explanation of how it works or how well it works that went beyond hand-waving references to polarization? All I could find was tedious exposition of why it is needed. To me it seems like vaporware. I would almost rather carry a sextant around with me (with an artificial horizon) and figure out where I am that way. Actually, you could probably invent a mini sextant that you just put in front of your smartphone and have it snap a picture and tell you where you are (to the extent possible fr
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I have not read the article, but: blue daylight is polarized in a way that you can tell the direction to the sun, and the approximate distance to the sun. There is some evidence to imply that the Vikings knew this, and used naturally occurring calcite crystals to navigate even in partly cloudy weather. (Calcite is mildly polarizing.) However, I doubt that this could be very accurate.
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You can look at their code if you like:
https://github.com/build-aweig... [github.com]
Tell me what you think, and look closely at the commands for the servo to move the filter...
Night (Score:2)
For nighttime, there has long been software capable of auto-discovering and tracking stars. Normally you tell it where you and it then finds the star you want, but there's no reason - so long as it knows the time accurately enough, that it couldn't tell you where you were from the night-sky.
I remember one in particular that used something like BBC Micro and a primitive low-res digitiser. You gave it lat-lon and time/date, pointed it at the night-sky, and it recognised certain stars and ten helped you auto
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In order to figure out where you are it is not enough to simply see the night sky. It has to measure angles between the stars and something on earth. Small angular errors will lead to very large position errors. For example, 1 minute of arc (1/60th of a degree) is about 1 nautical mile. So a degree is 60 nautical miles (1 nautical mile is more than a regular mile). The compass and accelerometer in a smart phone are not likely to be accurate enough for this to work to any high degree of precision. I would th
But what does it do? (Score:2)
Lots of hype, but what does it do? Can it tell you where you are to the nearest metre? kilometre? hundred kilometres?
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Is this a joke? (Score:2)
Aaaargh! Avast! (Score:2)
If I'm going to be navigating in my SUV with a sextant, then I want a carronade for use if someone cuts me off.
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Does navigating with a sextant while driving count as distracted driving? Or is this one of those cases where technology has gone out in front of the law again?
2:37 of my life I'll never get back (Score:3)
That was possibly the most pointless video I've every seen. WTF did I just watch?
But I digress... If this thing relies on a magnetic compass for navigation, you're pretty well screwed for any sort of practical ground vehicle.
Also, I want something that works indoors too.
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There are ways to continue to track movement based on a combination of altimeter, previously measured location, compass, so forth that could close the gap when you go inside. But really, disparaging or embracing this solutions seems very premature since we basically still have no information about its methodology. Think out of the box in the right way and suddenly you've turned well established and understood 2D technology into three dimensions and what was impossible becomes simple... and those sort of ans
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A magnetic compass? What happens when the poles switch?
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Wake me when that happens. If I'm still here.
What about at night? (Score:2)
That's nice. What happens when it's nighttime? What happens if you're inside a building? What happens if you have something obstructing your view of the sun, like buildings, or when in a canyon?
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I guess there are *some* buildings that are pretty large inside. But in general, if I'm inside a building, I know where I am; getting a sextant fix, even if I could, would not tell me anything I didn't already know.
Night--well, that's s.t. else.
User's positional data cannot be leaked to the int (Score:2)
Please elaborate more on this.
As I think user data can leak on matter their source.
Or am I badly wrong?
from Aweigh.... (Score:2)
Whatever. (Score:2)
So that's something.
Re:Intercept satellite GPS data is a concern??? (Score:5, Insightful)
Not really intercept. But the ability to make a GPS read incorrectly by broadcasting a false signal is proven.
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If it can still tell you what county you are in, it will be more accurate than this new system.
A sextant can pilot a ship to the correct port. It is not going to keep your car in the correct lane.
Re: Intercept satellite GPS data is a concern??? (Score:2)
And this isnâ(TM)t a sextant. A decent celestial navigator can find his position to within a few miles. I would be surprised if you could get close to that with a few light sensors and no precision parts.
Re:Intercept satellite GPS data is a concern??? (Score:4, Informative)
It is not going to keep your car in the correct lane.
Uh...I'm pretty sure GPS won't do that, either (at least civilian ones). Mine still occasionally decides that I'm still on the freeway when I'm on the off-ramp running parallel...
My GPS device (no maps) shows accuracy to about 5 meters. While 16 feet is amazing when you consider the size of the planet, a car lane is about 12 feet on the US Highway system and 8-10 feet in Europe.
I might trust GPS to tell me what road I'm on, but not what lane I'm in.
The new dual-frequency receivers can absolutely te (Score:2)
The silicon coming online with the current flagship phones (Snapdragon 855 SoC and Broadcom BCM47755 receiver) support the secondary L5 frequency from the major satnav systems, on top of the standard L1 - the *practical* accuracy of a dual-frequency system is about a half meter, more than accurate enough to provide lane-specific navigation.
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I'd rather save the $1200 and pay attention to where I'm driving. Then again I'm a cheapskate.
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Lane-level navigation (not autodriving) would be handy - I was in Vegas a couple of weeks ago, it would have been nice to be told "you'll need to be in the second-from-the-left lane, not the far left one you're currently in" a couple of times. It's not something I'd have specifically looked for in a new phone, but my five-year-old one finally crapped the bed so it was upgrade time. Now if they'd just get the software to use the L5...
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Well, being from vegas I can tell you that there is so much construction and shit that happens here(they will tear the same road up 3 times in 1 year). There is no device that will be able to tell you what lane to be in because the one your in may end. Google does about as good as you can as far as representing what lanes you should be in. Our roads are fucked, and are confusing as hell to people who don't live here, and even some that do. I have done a lot of service work and I work in construction so I've
Re:Intercept satellite GPS data is a concern??? (Score:5, Funny)
A sextant can pilot a ship to the correct port. It is not going to keep your car in the correct lane.
Sextants are also notoriously difficult to use while driving.
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Yea, how do you see through the tent. And do you and your partner have to unbuckle the seat belts?
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The Chinese Govt does not directly censor Chinese citizens.
You said something they didn't like, you either disappeared, or you didn't. That is something, but it isn't censorship.
Making broadcasters run a 2 second delay and bleep out any swear words is direct censorship. Fining somebody who swears on the air in order to prevent them from saying that next time, that is direct censorship. Sending them to prison for it is also direct censorship.
But if they just disappear from the airwaves, and nobody is really
Re:GPS does not need the internet. (Score:5, Insightful)
Probably the confusion is thanks to Google, and Google Maps.
On every phone I have, when I turn off all Google tracking and location data storage, eg 'via towers', Google Maps endlessly asks me to turn it back on.
For example, if I hit the 'centre on my location' button, it will say "For greater accuracy, please turn on this and that'.
There's no option to 'remember my answer', no way to make it stop, it just endlessly keeps popping up. Google is famous for 'bugs that are really nags' or 'bugs designed to screw over competition', so if there's a profit motive, expect a Google App to have a bug making it 'less painful' to submit to their spying or profit method.
Fuck. You. Google.
Re:Couldn't watch the video... (Score:4, Informative)
No matter, I did watch the video and it is 2:50 seconds and the only thing it tells you about their solution is it has something to do with navigation and involves a polarized lens. No specs, no details, no theory of operation, nothing. There was actually more in the TFS than the video.
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Wait you read TFS AND watched the video? You know this is slashdot right?
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Yeah. This thing is a scam. It "works"
As long as they develop the darn gadget properly
As long as it is not cloudy.
As long as you are outdoors and not moving.
As long as there is a level horizon.
As long as you have a precision time reference.
Statistically, all those conditions equate to : Never.
Btw. typically available sources of precision time:
1) connect to the internet (duh.)
2) Get it from GPS (duh.)
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1) No, a sextant can be used with stars, provided you have a horizon. Usually one uses the horizon just after sunset or before sunrise, since at those times the stars and the horizon are both visible. Aviators used to use a sextant at night with stars and an artificial horizon, i.e. a level.
2) You know when it is solar noon by taking shots from just before until just after local noon. (How far before and after depends on how accurately you know your present latitude.) And it's local noon--by definition-
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I'm skeptical about the idea too, but: "Where do you get accurate time? From GPS." Or from quartz watches. Heck, when I was in the Navy back in the 70s, we got time precise enough for navigation from a chronometer (and accurate enough because you could compute exactly how far off the chronometer was, based on its last calibration).