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Australia Earth Science

Australia Has Moved 1.5 Metres, So It's Updating Its Location For Self-Driving Cars (cnet.com) 134

An anonymous reader shares a CNET report: Australia is changing from "down under" to "down under and across a bit". The country is shifting its longitude and latitude to fix a discrepancy with global satellite navigation systems. Government body Geoscience Australia is updating the Geocentric Datum of Australia, the country's national coordinate system, to bring it in line with international data. The reason Australia is slightly out of whack with global systems is that the country moves about 7 centimetres (2.75 inches) per year due to the shifting of tectonic plates. Since 1994, when the data was last recorded, that's added up to a misalignment of about a metre and a half. While that might not seem like much, various new technology requires location data to be pinpoint accurate. Self-driving cars, for example, must have infinitesimally precise location data to avoid accidents. Drones used for package delivery and driverless farming vehicles also require spot-on information.ABC has more details.
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Australia Has Moved 1.5 Metres, So It's Updating Its Location For Self-Driving Cars

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  • by Anonymous Coward on Friday July 29, 2016 @02:26PM (#52607913)

    Self-driving cars, for example, must have infinitesimally precise location data to avoid accidents.

    Somehow I suspect it's a matter of centimeters rather than nanometers. Need less hyperbole and more accuracy!

    • by Pseudonymous Powers ( 4097097 ) on Friday July 29, 2016 @02:35PM (#52607991)

      Self-driving cars, for example, must have infinitesimally precise location data to avoid accidents.

      Somehow I suspect it's a matter of centimeters rather than nanometers. Need less hyperbole and more accuracy!

      Good collar, Pedant Police, but move over now. I'm with the Pedant FBI. I'm taking charge of this investigation.

      Nanometers may be small, but they're not infinitely small, which is what infinitesimal means. They're barely even any closer to infinitely small than centimeters. Also, we wanted to be more precise here, not less, so what you'd really want in this situation is infinite precision, not infinitesimal precision.

      Let's keep it pedantic out there, citizens.

      • All law enforcement officers will be required to carry precision calipers to verify that a safe following distance is maintained by drivers at all times.

      • Nanometers may be small, but they're not infinitely small, which is what infinitesimal means. They're barely even any closer to infinitely small than centimeters.

        Well, FWIW, *both* of them are infinitely larger than infinitesimal despite the fact that nanometres are closer. So does this mean that the "infinity" between centimetres and infinitesimal is larger than the infinity between nanometres and infinitesimal? Hmmmmmm......

        Also, imagine a line of people standing single-file, extending infinitely in both directions. There are, of course, an infinite number of people. Now, imagine each of these people is joined by a partner. Are there twice as many people now? Do

        • So does this mean that the "infinity" between centimetres and infinitesimal is larger than the infinity between nanometres and infinitesimal?

          No. You can subtract a constant from infinity, subtract any finite number from them, and the size of the infinity doesn't change.

          • Similar to the concept of eternity, which is a long, long time, especially there near the end (sarcasm),
          • So does this mean that the "infinity" between centimetres and infinitesimal is larger than the infinity between nanometres and infinitesimal?

            No. You can subtract a constant from infinity, subtract any finite number from them, and the size of the infinity doesn't change.

            and of course, (for those who are not familiar with the concept) the countable infinity, such as the aforementioned infinitely long line of people, equivalent to the integers or the whole numbers, is infinitely smaller than the real numbers, an infinity of which exists between any two integers.

        • by legRoom ( 4450027 ) on Friday July 29, 2016 @10:11PM (#52610297)

          Also, imagine a line of people standing single-file, extending infinitely in both directions. There are, of course, an infinite number of people. Now, imagine each of these people is joined by a partner. Are there twice as many people now? Does this mean there are "2 x infinity" people? But surely you can't do that to infinity. Er...

          Spoiler; I'm not a mathematician, and don't have the answers, I'm just throwing this out here for amusement. Though I guess someone who knows more about this than I do could explain it

          Modern mathematics recognizes the existence of different "sizes" of infinity, but they don't follow the standard rules of arithmetic. The basic idea is not complicated: anyone who can grasp intermediate algebra should be able to understand it, eventually. (I'm sure that my explanation won't be good enough for a lot of people though; try searching YouTube for "Hillbert's Hotel paradox", maybe.)

          However, the infinite is far outside our everyday experience, so a bit of vocabulary from higher math will make it a lot easier to discuss the examples which follow:

          set [wikipedia.org] - an unordered collection of unique elements. Elements can be numbers, names, other sets, or whatever. Duplicate elements are not allowed: the number 53 (for example) is either in a particular set, or it is not; the set cannot contain two "copies" of 53, or anything like that.

          cardinality [wikipedia.org] - this is the "size" of a set. Two sets have the same cardinality if and only if their members can be put in one-to-one correspondence. For sets with a finite number of elements, such as the set of letters in the English alphabet, the cardinality is simply the number of elements in the set: 26, in this case. This is easily proven by simply associating a number with each letter (A => 1, B => 2, C => 3, ...).

          Where things get interesting, is when we try to compare the sizes of two infinite sets, such as the set of all even numbers (0, 2, 4, 6, ...) versus the set of all whole numbers (0, 1, 2, 3, 4, ...). We cannot simply count the number of elements using finite whole numbers. Instead, we must use transfinite cardinal numbers [wikipedia.org]. To understand what those are, consider some classic examples:

          Hillbert's Paradox of the Grand Hotel
          Imagine that Hillbert's Hotel has an infinite number of rooms, every one of which is occupied by exactly one person. The rooms are each numbered with a sign on the door: 1, 2, 3, 4, ...

          Question: A new guest arrives, and asks the host for a private room. Can the host provide him with a room without doubling anyone up, or kicking anyone out of the hotel?

          Answer: Surprisingly, yes he can! Here's one way he could do so: the host gets on the public address system and instructs every guest to pack his bags, leave his room, look at the number on the door, add one to it, and move into the room with that new number. So, the guy in room #1 moves into #2, the guy in #2 moves into #3, and so on.

          At a finite hotel, this could never work: whoever was in the last room would be kicked out, with no higher numbered room to move into. However, in Hillbert's infinite hotel there is no last room, and so there is no problem. Everyone moves over by one room, and the new guest moves into room #1.

          Conclusion: infinity + 1 = infinity.

          Question: Suppose that the neighbouring Cantor's Infinite Hotel (same setup) needs to be fumigated (or nuked from orbit) because it is infested with an infinite number of cockroaches. The manager of Cantor's Hotel asks the host of Hilbert's Hotel if he can temporarily accommodate an infinite crowd of additio

          • I'm already vaguely aware of parts of these (including the basic idea that there are different levels of infinity) but while I can "accept" the logic, I don't really "get" it and part of my brain is still telling me I'm being complicit in fooling myself or that there's a logical paradox at some level. :-/
    • by s_p_oneil ( 795792 ) on Friday July 29, 2016 @02:53PM (#52608133) Homepage

      Actually, self-driving cars don't need any location information at all to avoid accidents.

      It's not like a GPS can tell them if a light they're approaching is red or green, if there's a car in front of them, or if that hypothetical car is currently slamming on its brakes. It can give them an idea of where to turn, but it can't tell them if there's a pedestrian, a car, a wall, a lake, a big gaping sinkhole in the road, a flooded section, or something like that in the spot where it wants them to turn.

      • Location information doesn't need to be GPS. Autonomous machines guiding themselves without GPS use localization based off of other factors (lidar/radar/sonar) or a combo of sensors. To see the light ahead is changing color, requires an understanding of distance relevant to the vehicle, to react. It does require location information to navigate, but it doesn't have to be Global positioning it can be local coordinates.

        • What you're referring to has nothing to do with the location of the vehicle itself (which is what this article is about), but the location of external objects relative to the vehicle.

          The most important thing a self-driving vehicle accurately needs to track about itself is its current speed. Next would be the current state of the steering wheel, accelerator, and brakes (and perhaps whether the driver is trying to take over to avoid an accident). I suppose there are a number of other things you wouldn't norma

          • The algorithms collectively used in autonomous vehicles lacking in GPS or in addition to it are called SLAM. Simultaneous localization and mapping is defined as follows: In robotic mapping, simultaneous localization and mapping (SLAM) is the computational problem of constructing or updating a map of an unknown environment while simultaneously keeping track of an agent's location within it.

            The equations are designed to calculate the responses of the vehicle or object as it moves through an unknown environmen

        • Quite. GPS is essentially a "cheat system" to make it brain-dead easy to determine your precise location. Without it our robots could still theoretically determine their location via landmarks , street signs, etc, just as we have done since prehistory. It's probably a heck of a lot more difficult to implement though.

      • Actually, self-driving cars don't need any location information at all to avoid accidents.

        It's not like a GPS can tell them if a light they're approaching is red or green, if there's a car in front of them, or if that hypothetical car is currently slamming on its brakes. It can give them an idea of where to turn, but it can't tell them if there's a pedestrian, a car, a wall, a lake, a big gaping sinkhole in the road, a flooded section, or something like that in the spot where it wants them to turn.

        Indeed. human drivers have driven for a long time, and many still drive, without access to GPS info, while still avoiding accidents.

    • And, they don't use GPS to avoid accidents. That would be... totally insane. That's just a "wow"-level stupidity to dump out while trying to explain something.

      * (Yes, I used stupidity as a noun. Get over it, it's an open language.)

      • You seem to be assuming that all accidents are a result of something changing in the environment (e.g. other cars, pedestrians, etc). Knowing not to turn too soon would also help avoid single-car accidents. Other sensors may be able to prevent such things, but accurate GPS could certainly be part of it.

        • You seem to be assuming that all accidents...

          As soon as you decided to assume that I'm making an absolute statement, you could also just have assumed that you didn't understand what I wrote, and attempted to re-parse until you teased out a logical statement.

          And then you follow up by just hand-waving and presuming GPS "may be able" to prevent some things. But you're not really sure. You could have just as easily assumed that the maybe stuff you imagined were brought in by your absolute, rather than being implicated by what I actually said.

          But consider

    • by tchdab1 ( 164848 ) on Friday July 29, 2016 @04:10PM (#52608781) Homepage

      i will keep this in mind the next time I drive to Australia. I'd hate to miss it entirely.

    • Australia is moving about 2 nanometers per second. Fingernails grow at a rate of about 1 nanometer per second. So Australia is moving pretty fast.
      • by dwywit ( 1109409 )

        We're moving generally north, yes? So if I point my fingers southwards, I can watch my fingernails *not* catch up?

        Mind=blown

      • Australia is moving about 2 nanometers per second. Fingernails grow at a rate of about 1 nanometer per second. So Australia is moving pretty fast.

        Yes but the truth is that Australia is not moving. All the other land masses are moving!
        And if I recall one of the sea level references that "proves" sea level is rising is in Australia.
        It is possible assuming this observation is true that the sea level is constant and Australia is sinking.
        But since sea level is rising along with the number political solutions to extract carbon taxes I want to know
        more.

        More data please. It is obvious that India and Asia are colliding and crashing into each other but
        some o

  • No they do not (Score:5, Insightful)

    by SuperKendall ( 25149 ) on Friday July 29, 2016 @02:27PM (#52607919)

    I'm sorry, but when driving I do not have "infinitesimally accurate location data". I have eyes and ears, I and use them to not get in accidents. Turns out that many things on roads are not fixed at all and may appear or disappear at any time...

    • How else can the Aussies play Pokemon Go while driving if their cars are not perfectly accurate?

    • by suutar ( 1860506 )

      You don't. They do (running off the edge of the road because you thought it was a meter that-a-way is an accident).

      • The point is that that data means nothing when there's construction, or the edge of the road is washed out, or a car (or truck...) is stopped in the road... I would expect self-driving cars to use GPS only for an idea of where they are and what roads to use to reach a destination; for actually driving GPS is utterly useless because anything about a road can change any time, you have to use some kind of sensors to figure out how to drive on the road you are on, not the road as fixed GPS data in a database so

  • by OlRickDawson ( 648236 ) on Friday July 29, 2016 @02:27PM (#52607921)
    I always knew they were a little off
    • Standing upside down all-day long does do funny things to people.

      • Standing upside down all-day long does do funny things to people.

        What did you think Max was Mad about?

    • Actually, they're the ones standing still, it's the rest of the world that's moved.

      In all seriousness though, does anyone know what the GPS system itself uses as a reference point to correct for system drift?

      • Re: (Score:2, Informative)

        by Anonymous Coward

        http://www.unoosa.org/pdf/icg/2012/template/WGS_84.pdf

        WGS84

  • by Morpf ( 2683099 ) on Friday July 29, 2016 @02:27PM (#52607925)

    If it was the case we would be in deep trouble considering the typical error in GPS. That is the reason why other sensors like LIDAR and cameras are also used. GPS is for having a general clue where you are, and 1,5 m accuracy would be plenty for that.

    Slashdot editing...

    • by Anonymous Coward

      Precision GPS needs to be with respect to a set of base stations. Like the Continuously Operating Reference Station (CORS) https://www.ngs.noaa.gov/CORS [noaa.gov].
      There is no reason why the coordinate frame cannot be defined to move with the subcontinent.
      The CONUS has portions that move in different directions so we both attach the coordinate frame to one of the plates, and do periodic readjustments
      http://www.ngs.noaa.gov/web/surveys/NA2011/ [noaa.gov]

      • by Morpf ( 2683099 )

        This is true and there are definitely use cases for high precision GPS, requiring special receivers. But the summary and headline were explicitly talking about self-driving cars, where this accuracy is not needed.

      • In the case of GPS though, the system isn't physically anchored to anything. I assume it uses some terrestrial reference point(s) to correct for orbital drift, but I believe the system as a whole is constantly broadcasting all the information to fully define a coordinate system. Anchor those coordinates to Australia, and it's the rest of the world that has apparently drifted 1.5m.

        Having the devices themselves translate between canonical GPS coordinates and locally defined ones might be viable, but would r

        • by Anonymous Coward

          Geoscience Australia, where I work, is implementing a updated but fixed Coordinate Reference System pegged at the year 2020 called Geodetic Datum of Austrlai (GDA2020) which removes drift error accumulated since GDA94, after which time a time component will be added to all coordinates so that GDA2020 will be the last update as the time component will cater for continued drift.

        • Perhaps the GPS system could be extended to periodically broadcast updated translation matrices for the various tectonic plates?
          GPS helps you to determine your longitude, latitude and hight (distance from center of the earth).
          It does not tell you, nor any plate, nor any tree nor any animal: what there is. For that is the map. And now look on your map and you figure: the particular road crossing you are standing at has its center at: X, Y. Probably a surveyor has painted the coordinates on the ground for y

          • >> terrestrial reference point(s) to correct for orbital drift
            > No it does not.

            OP's assumption is more accurate than your response. What is interesting is you go ahead and explain how the system compensates for drift, after saying it doesn't. Ground based stations correct the satellite's internal position, the satellite then sends that to the receivers. so where those ground based control systems are located is going to be the GPS reference. 2 SOPS contacts each GPS satellite regularly with a nav [wikipedia.org]

            • Maps are not in X, Y coordinates but longitude/latitude. Otherwise they would not work.

              However there are approximations for Survey maps and "cadastral land register" maps because those make calculating land areas on a "somewhat local" scale easier (Gauss Krueger Coordinates). GPS is not related to them, and street maps in navigation modules/software use long/lat.

              "terrestrial reference point(s) to correct for orbital drift" probably I misunderstood at what the parent was aiming. Yes, the satellites use groun

            • Thanks, that's what I was wondering about. I didn't see any mention of if/how they compensate for movement of the ground antennas though, since nowhere on Earth is perfectly stationary. I wonder if they simply say "this point is defined as X/Y/Z coordinates", or if they attempt to track compensate for it.

          • You completely missed my point. As you say, the satellites all say "I am here (insert coordinates - 26,560km distance to earth center) and my local time is hh:mm:ss.xxxx", but how is that coordinate system defined?

            THAT is the key question that defines how the coordinate system is "anchored". And since it relies on ground-based reference stations (though from Dare's comment it's sounds as though the stations are the active component there, and periodically update the satellites understanding of where they

  • by npslider ( 4555045 ) on Friday July 29, 2016 @02:33PM (#52607967)

    Does this mean that Apple Maps is now correct? I'm tired of seeing so many Kangaroo's drive off into the Ocean because they relied too heavily on the Maps app.

  • [...] must have infinitesimally precise location data [...]

    No wonder the Tesla self-driving AI is getting into crashes. It's too busy figuring out the Archilles and the tortoise paradox.

    https://en.wikipedia.org/wiki/Zeno's_paradoxes#Achilles_and_the_tortoise [wikipedia.org]

  • So that's how you relocate a penal colony of that size.
    • On the upside, if Australia keeps moving in my direction, I will be able to drive directly to Australia in 172,085,760 years or so. Save me a plane ticket! Now I just have to find something to keep me occupied till then.

      • On the upside, if Australia keeps moving in my direction, I will be able to drive directly to Australia in 172,085,760 years or so. Save me a plane ticket! Now I just have to find something to keep me occupied till then.

        we must start now to build a wall to keep this nation of former convicts from crossing our borders. when australia sends us their continent, they do not send us their best.

  • Australia just can't move freely around the globe without something else moving. So is happening to the other tectonic plates?

    The ABC link mentions that the Australian plate is moving North at 7cm/year and that the Pacific plate is moving West at 11cm/year, but surely they can't be the only ones that move.

    • by rossdee ( 243626 )

      Well on the other side of the world, the UK is leaving Europe

      I'm glad I don't live on the coast, there could be some big tsunamis...

  • by ktakki ( 64573 ) on Friday July 29, 2016 @02:55PM (#52608147) Homepage Journal

    ...where's my continent?

  • Everyone knows that a GPS like TomTom doesn't rely on the GPS coordinates it's given. Instead it assumes that it is on a road, assuming slightly stronger that it is on the road it's supposed to be on than on a nearby road, and corrects it's position.

    A TomTom would not be able to recognise for example that you are driving on the wrong side of the motorway. It would find your rough position (GPS is "rough" with an error of a few meters if you're lucky), detects your motion vector, the figures out the locatio

  • Beacons? (Score:2, Interesting)

    by HalAtWork ( 926717 )

    Rather than wait until someone notices a large margin of error, why not install immobile beacons in key locations that constantly monitor their locations and report back any differences?

    • Immobile beacons that don't shift along with the continent? Even survey points shot into the ground can fluctuate about a foot within a year due to frost drift. I wonder where these stations that don't shift with the continent get anchored.

      • by Fwipp ( 1473271 )

        Beacons that do shift with the continent - the idea is any movement by them, you can also assume that the points between the beacons have moved.

    • Re:Beacons? (Score:5, Informative)

      by Goldenhawk ( 242867 ) on Friday July 29, 2016 @03:16PM (#52608337) Homepage

      Already done. It's called Ground Based Augmentation System (GBAS).
      http://www.faa.gov/about/offic... [faa.gov]

      There's also a system called WAAS, Wide Area Augmentation System, and others.
      http://www.novatel.com/an-intr... [novatel.com]

      A short description (I know, TLDR...) is that ground-based transmitters broadcast an error signal - the difference between received data and the actual known surveyed position. Any properly-equipped receiver uses this signal to offset its GPS-measured position accordingly.

      My Garmin GPS that I got back in 2005 used the WAAS system. It's been around for quite some time.

    • Because by publishing data periodically everybody has synchronized navigation data, and even if somebody doesn't update, if you know that it is easier to predict what data they will have.

      With continuously corrected data you have no idea what somebody actually means when they give you a coordinate.

      The relative coordinates are much more important than the absolute coordinates.

    • Rather than wait until someone notices a large margin of error, why not install immobile beacons in key locations that constantly monitor their locations and report back any differences?

      They do.
      http://www.navipedia.net/index... [navipedia.net]
      https://en.wikipedia.org/wiki/... [wikipedia.org]
      http://www.trimble.com/gps_tut... [trimble.com]
      https://www.ngs.noaa.gov/CORS/ [noaa.gov]

      With regional to local corrections accuracy to 10cm is almost easy.
      A number of auto GPS devices have an additional receiver for exactly this.

      Surveyors can gather high quality data with the assistance of a recording
      stationary receiver (one or more) and post process measurements made
      by the moving instrument.

      Follow the links to Augmentation https://en.wikipedia.org/wiki/... [wikipedia.org]

      O

  • womp rats (Score:5, Funny)

    by kimvette ( 919543 ) on Friday July 29, 2016 @02:58PM (#52608167) Homepage Journal

    I used to bullseye womp rats in my T-16 back home. They're not much bigger than two meters. But, now I miss because GPS is off.

    • He didn't use The Galactic Positioning Service, he used the Force!

      • Kid, I've flown from one side of this galaxy to the other. I've seen a lot of strange stuff, but I've never seen anything to make me believe there's one all-powerful Force controlling everything. There's no mystical energy field that controls my destiny. It's all a lot of simple tricks and nonsense.

        • You don't want to use GPS anymore
          I don't want to use GPS anymore

          Your going to go home and rethink your life
          I'm going to go home and rethink my life

        • *kimvette starts choking

          I find your lack of faith disturbing

  • Well, if everything had been done relative to the same datum to begin with, why would it matter that it shifted? Or perhaps the issue is that things have been incrementally added to databases based on the same datum which is slowly drifting off correct that is the problem...
    • This was my first thought as well... but I suspect the problem is the latter - where some data in the database has incorrect coordinates and needs to be adjusted so that it is properly relative to other data in the database.

      The trick is to next automate the update of coordinates in the database based on the time that has elapsed since they were last "corrected" - and I'm sure with a bit of annual tracking and simple math, someone could implement such an algorithm.

    • For most things it doesn't matter, but something like "augmented reality" would be putting the pixels in the slightly wrong spot. A vehicle auto-pilot should be able to do just fine with a 1m error, because it has to see the road to work at all, but the HUD might still be off, and it would sometimes not choose the best lane anymore. It could even make a wrong turn in a complex urban intersection.

      Even without that, if you never update it becomes a bigger problem over time.

  • Australia is changing from "down under" to "down under and across a bit".

    Men at Work [wikipedia.org] re-unite to update song lyrics [wikipedia.org].

  • As if PST wasn't bad enough, what kind of pain will it be to partially migrate through a new time zone over a period of a millennium...

  • Self-driving cars, for example, must have [...] precise location data to avoid accidents.
    Should be a no brainer that self driving cars don't use GPS for their "self driving". Besides the fact that your "GPS location" can be off by dozens of meters for no apparent reason, it can be gone completely in tunnels, parking houses, between sky scrapers etc. Should be a no brainer that a car can not use GPS for anything than plotting a course from A to B. Everything else is done with cameras, lidar, radar and even

  • Self-driving cars, for example, must have infinitesimally precise location data to avoid accidents.

    If self driving cars are more reliant on GPS data than actual real world feed back to avoid accidents then they better be banned as I don't want that shit anywhere near me.

  • So Australia moved a metre and a half, and their gps wasn't updated.
    That explains how they came to be all driving on the wrong side of the road.

    Does that also explain why they've got a whole continent to themselves, but there are only 24 million people there?
    It must be they're the survivors of the switchover to wrong-side driving.

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