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Dead Reckoning For Your Car Eliminates GPS Dead Zones 151

Posted by timothy
from the walk-30-paces-then-turn-left dept.
cartechboy writes "We've all been there. You're relying on your vehicle's built-in navigation system to get to that meeting downtown, but then suddenly the car loses the satellite signal due to the concrete skyscraper canyon you're in--and you're about to be late. Swiss semiconductor manufacturer U-Blox thinks it has the solution with 3D Automotive Dead Reckoning, or 3D ADR for short. It's a new navigation chip that uses the vehicle's built-in sensors to track speed, horizontal movement, and elevation. The 3D ADR system measures movement in three dimensions, letting the navigation system can keep track of the vehicle's location even when it loses its connection to GPS satellites. Imagine never having to see your navigation screen saying connection lost again. In an age where our phones have accelerometers and compasses, it's amazing your car is still trying to catch up, right?"
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Dead Reckoning For Your Car Eliminates GPS Dead Zones

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  • by Electricity Likes Me (1098643) on Saturday February 08, 2014 @10:27AM (#46195305)

    Seriously this isn't new. Good in-car nav systems have had dead reckoning based on wheel position + speed for ages.

    • It's not even new for uBlox, I was reading about their dead reckoning systems in their (existing, shipping) product literature 5 years ago...

      • by kheldan (1460303)
        No, it's not a new concept (someone above mentioned their car having it in 2004, but I know for a fact that some Japanese auto manufacturer had a dead-reckoning nav system even back in the 1980's or 1990's), and it's not new for U-Blox either (I worked at a defense contractor, and we used U-Blox GPS receivers, I personally worked with them, and knew of their dead-reckoning technology, and this was almost 10 years ago now), but U-Blox makes GPS receivers for high-end embedded applications, not so much for co
        • cutting-edge GPS receivers can pull satellite signals out from all the way down to a few dB above the noise floor now, even in "urban canyon" locations where signal is blocked by buildings as well as being muddled.

          I'd certainly hope so, considering that the satellite signal is considerably below the noise floor once it reaches the ground... (sources vary between 20dB [ucalgary.ca] to 26dB [gpssource.com] below the noise, I didn't do the math myself)

    • by Anonymous Coward

      Yup, my Peugeot (that's a European car maker) has that. Works superbly. Still knows where you're going when you're 3 floors down in an underground parking. Gives very funny results when you take a ferry which turns 180 degrees before docking.

    • by Bigger R (131370)

      Agreed, this is not new. However Beta is new. Sometimes it's good to stick with the old.

      Dissapointing. On the upside, it may free up time for other activities after over a decade of visits.

      Hope someone can make a good call on this.

      Bigger R

    • by AmiMoJo (196126) *

      In fact the very first in car navigation systems used dead reckoning. Honda made one with a map on a cylinder and a little cross hair that you positioned over your starting position. As the car moved the cylinder rotated and the cross hair moved from side to side, following your position on the map.

      Android phones have had the ability to use dead reckoning for years now too.

      • Android phones have had the ability to use dead reckoning for years now too.

        I doubt it, as the accuracy of position on the map is very poor.

        • What do you know about Android phones? You have an iDevice grafted on your right arm, as we all well know.

          Did you only chime in because somebody said 'Android' in a comment?

          I run NetBSD on my SE/30 and I hope one day to run Android on my iPod Touch.

      • by Grishnakh (216268)

        Android phones have had the ability to use dead reckoning for years now too.

        Citation needed. This sounds like bullshit. You get dead reckoning by connecting to some sort of feedback device, namely the wheel sensors or odometer in the vehicle. Android phones don't have a connection to your car's computer; they work entirely off of GPS signals. In-car nav systems aren't like this; they use both GPS and dead-reckoning to get better accuracy than GPS alone (watch what happens when you drive into a parking g

        • You get dead reckoning by connecting to some sort of feedback device, namely the wheel sensors or odometer in the vehicle. Android phones don't have a connection to your car's computer; they work entirely off of GPS signals.

          In theory, if the accellerometers and gyroscopes were precise enough, they could use those. Airplanes were already using inertial reference systems way before GPS was invented. Initialise the box with a starting position while standing still, and it will keep track of where you are using just gyroscopes and accellerometers. Taking the rotation of the earth into account and all.

          Unfortunately, though, accellerometers in even today's newest phones are nowhere near precise enough for that purpose.

          • by Grishnakh (216268)

            Yeah, exactly. Just all the noise they'd generate from being handled by humans would be too much. Maybe if the phone was rigidly mounted in the car.

        • by jtara (133429)

          Modern phones, including Android, iPhone, etc. etc. etc. have this ability. Whether or not a given navigation app uses it is another matter.

          You don't have to use wheel sensors or the odometer (did you mean speedometer?), although those are useful inputs.

          A more applicable and general term than "dead reckoning" is "sensor fusion".

          Here's what Wikipedia has to say about dead reckoning:

          "In navigation, dead reckoning (also ded (for deduced) reckoning or DR) is the process of calculating one's current position by

          • by Grishnakh (216268)

            So how do you filter out all the extra accelerations from the users dropping the phone on the floor, fiddling with it, moving it around, etc. while the car is in motion? Phones aren't rigidly mounted in cars.

            And considering how often Google Maps thinks I've instantly teleported to different places while driving, it doesn't look like all this theory really holds up in reality.

            • Those accelerations aren't 'extra' - they are really happening to the phone and so would have to be taken into account too.

              The problem isn't that the phone is moved around in the car, the problem is that the accelerometers and gyros of the class that exist in phones are orders of magnitude too noisy and imprecise to be used to dead-reackon for more than a few hundred milliseconds.

              There is absolutely no way on earth that any cellphone that exists today uses any of its inertial sensors as part of its GPS solu

            • So how do you filter out all the extra accelerations from the users dropping the phone on the floor, fiddling with it, moving it around, etc. while the car is in motion? Phones aren't rigidly mounted in cars.

              They'll either cancel out (if it ends up in the same place) or be within an acceptable margin of error (most GPS units aren't accurate to the distance between the right front and real left seat anyway).

              And considering how often Google Maps thinks I've instantly teleported to different places while drivi

        • by AmiMoJo (196126) *

          There used to be an option called something like "sensor aiding" which used accelerometers to reduce GPS power consumption and provide some coverage when the GPS signal was lost. For example when driving the GPS could drop down from 1 update/second to 1 update/10 seconds and use the accelerometer to check that the vehicle maintains a more or less constant speed in-between. Accelerometers use a lot less power than GPS.

          Most phones have accelerometers. They are very cheap and necessary for things like screen r

      • I sort of doubt Android phones have any useful sort of dead reckoning. My experience of playing around with accelerometers on phones is that they can tell you roughly which way is up and can detect sharp shakes or jolts and that is all. Attempting to integrate the results over any period of more than about a second results in drift so bad it is useless.

    • My Zephyr (now MKZ) definitely used dead reconing, back in 2007 or so.

      • 2004? I was working on vehicle location systems that had DR at least 10 years before that (especially useful since IIRC there wasn't a full GPS satellite constellation then). DR isn't exactly new - Columbus used it.

    • by GoChickenFat (743372) on Saturday February 08, 2014 @11:49AM (#46195841)
      My car has had this since I started to drive. It's called "using my brain".
    • I assume that military units (ships, submarines, airplanes) have been integrating navigational data from multiple sources (LORAN, GPS, INS...) for decades. Nothing else would make sense in case a war erupts, really (you can't rely solely on sats when (a symmetric) war happens).
      • In maritime navigation DR is one of THE most fundamental way's of navigating. As it has been for litterally ages.

        http://en.wikisource.org/wiki/The_American_Practical_Navigator/Chapter_7
        • That is true, of course, but even back then, it needed periodic data integration (i.e., astronomical or solar observations) to keep the drift bounded.
          • That is absolutely true. The whole idea of navigation, wether it is on land or at sea is that you take measurements. From a practical standpoint it doesnt really matter wether that is from celestial bodies (natural or man-made) or from known landmarks.
            One of the problems a sumarine (whilst being submerged) has is that it can`t do any measurements of that kind. Like LORAN-C, GPS, INS, landmarks, celestial navigation et cetera. So angle, distance and time are the main navigational tools. The main skewing fact
            • One of the problems a sumarine (whilst being submerged) has is that it can`t do any measurements of that kind. Like LORAN-C, GPS, INS, landmarks, celestial navigation et cetera. So angle, distance and time are the main navigational tools

              It could also make gravimetric measurements. And it absolutely has to use INS. But then again, unless it's an SSBN, even at war, occasionally sticking out the electronic mast to get a GPS fix doesn't seem to be a problem. After all, a fast attack submarine has to communicate from time to time, and it can get a navigational fix whenever it's forced to stick out the mast for reasons of communication. On open sea, an error of a mile a day [vectornav.com] seems to be good enough when traveling underwater for most purposes.

    • All car navigation systems pretty much required this when the GPS system was still hobbled by the ~100m uncertainty caused by Selective Availability. (Ended by Clinton in May 2000 [gps.gov]).

      The implementation is actually quite trivial: One sensor on each front wheel gives you two revolution counters (odometers).

      Distance traveled is proportional to the sum of the two counters, while the difference in counts is proportional to how much you have turned.

      As long as you have GPS reception you can use that to calibrate the

      • Close, you use the speed sensor to figure out speed and the steering wheel sensor to figure out direction.
        Cars only have individual wheel sensors for ABS/stability control. No other systems touch those sensors.

      • I know I can upset my ABS system, bringing on the the error light, by doing burnouts and handbrake slides. Burnouts give false readings on the from wheels and handbrake slides give false reading on the rear wheels.

        Would play havoc with such systems but to be fair I don't normally do these while navigating.
    • by X0563511 (793323)

      Hell you've probably got one of those vibrating-comb gyroscopes in there too, they have had those for quite some time and they are usually included in typical "accelerometer" chips.

    • Not new..

      Submarines used it for navigating below the ice cap in the 50's.

      Early Sperry-Rand gyros were too large for a phone and
      perhaps not as good as modern micro machined devices
      today but could get them from A-B-C.... Recall the oldish phrase
      close only counts in horseshoes, hand grenades and A-bombs.

      • I stand corrected....
        c1958 the technology of the North American Aviation N6A-1 Inertial Navigation System was used (per WP).

  • by Trepidity (597) <delirium-slashdo ... org minus author> on Saturday February 08, 2014 @10:30AM (#46195321)

    In an age where our phones have accelerometers and compasses, it's amazing your car is still trying to catch up, right?

    Actually I think it's the opposite, it's only being in a car that makes dead reckoning with any kind of accuracy feasible. A car is a reasonably large and stable platform, which already has good speed information, and can have some accelerometer-type information added relatively easily. A smartphone does have an accelerometer, but the data is far too noisy to do reasonable dead reckoning, because in addition to the macro movements (someone walking, biking, or driving down a street) there area bunch of micro-movements that produce high local acceleration (putting the phone in/out of pockets, taking steps while the phone's in your pocket, etc.). It makes for a much more complex dead-reckoning problem, because instead of just tracking broad movements (car goes 10m this way) you have to resolve a ton of tiny movements (phone was moved 0.3m into pocket, then rapidly accelerated 0.1m left due to owner being jostled on the subway, etc.), which tend to pile too much accelerometer noise on top of the broader movements that you really want to track.

    In short, taking a known starting position and keeping it updated via accelerometer data is a lot easier if your accelerometer is on a car, vs. on a handheld device.

    • by drinkypoo (153816)

      The summary is even dumber than you thought, since all cars in the developed world now have yaw control, which uses (DUN DUN DUN) accelerometers.

    • by AmiMoJo (196126) *

      Dead reckoning works fine on my phone. Some apps, like Navitime, let you navigate on foot inside stations where there is no GPS signal using it.

      All you have to do is average the readings out. You don't need pinpoint accuracy, and GPS typically only gives you +/-5m on a good day anyway. A car will have lots of random juddering too in counties with shit roads like the UK.

      • Some apps, like Navitime, let you navigate on foot inside stations where there is no GPS signal using it.

        Huh? Can you show me which Navitime app does this? Because none of the apps on their website claims to.

        • by AmiMoJo (196126) *

          http://www.youtube.com/watch?v... [youtube.com]

          It only seems to be supported in the Japanese version, probably because they have better data for train station layouts available.

          It's actually quite a clever system. It can tell when you are on the train because of the high rate of acceleration. When get start walking the rate is constant but low. It knows the distances in meters and does a rough estimate using the accelerometer to notify you when you need to change direction.

      • by aix tom (902140)

        A car will have lots of random juddering too in counties with shit roads like the UK.

        But that's not really *random*. Perhaps an updated Navigation system will be able to pinpoint your location exactly just by analysing the frequency of the potholes you drive through.

    • by kipsate (314423)
      Not only that, but the car is on a road and the nav system knows where the roads are. If the nav system has an approximation of the location of the car, and the car makes a right turn, then it can know and sync the position of he car to be on that road.
    • My old cheap Samsung tracks via accel. and compass most of the time, because the GPS is so poor. As long as it can get a GPS fix every few minutes it covers up for the crappy GPS antenna quite well. IIRC the 'Tomtom' that I used to use at work would do the same thing, only of course it didnt need the capability near as often, but you could drive through a long tunnel with it and still show actual position until the signal re-established at the other end.

      Presumably there is something new here, but the basic
      • IIRC the 'Tomtom' that I used to use at work would do the same thing, only of course it didnt need the capability near as often, but you could drive through a long tunnel with it and still show actual position until the signal re-established at the other end.

        The dedicated sat-navs tend to just assume that you are continuing at the same speed on the same road. Than give up after a period of time.

  • There was a system called ETAK (1983... see wikipedia). At the time they "Said" Etak was a Polynesian word that meant "the world moves" and that the technique came from the polynesian nevigation methods.

    Nothing new to see here... Just repackaging masquerading as new

    • by kamakazi (74641)

      Yup, this, I think. I definitely remember in my much younger years a Popular Science review of a system that used dead reckoning, basically you told it where you were to start, and it used distance measuring, nothing as sophisticated as accelerometers, but whenever you turned a corner it would realign itself to the map.

      It did not work well if you drove many miles in a straight line, but worked well in city driving, which of course was all that was needed when people could still use a map to find the right

    • by mrbester (200927)

      So not some manager's girlfriend's name spelled backwards then.

  • by Anonymous Coward

    Beta, brought to you by the same people that fucked Sourceforge.

    Fork or die.

    • Who would want to host code on a website that openly promotes forgery? I always wondered that. Also, many small projects should never centralize on a big conglomerate that can go away at any time.

  • My 7-year-old Prius tracks my movements in tunnels, inside a garage with no GPS, etc. It indicates my changing heading and position as I back out of a parking space, etc.
  • Beta is more than cosmetics or aesthetics. The new design ruins the one thing that makes /. what it is -- the commenting system. I only come here for the comments [slashdot.org], not the 2-day old articles nor the erroneous summaries.

    I do not see the changes of Beta as improvements. What is wrong with Slashdot that demands breaking its foundations? This is not change for the sake of change, but, as others have commented, an attempt to monetize /. at any any cost [slashdot.org], and its users be damned.

    Our complaints have fallen on deaf

  • Welcome to 2000 !!! (Score:3, Interesting)

    by thygate (1590197) on Saturday February 08, 2014 @10:57AM (#46195503)
    seriously, my old bimmer's on-board navigation already did this 15 years ago ! other than that, I've used u-blox in several embedded designs, and they are by far the most fun GPS unit to play with. They have some great pc software for it too. And they've had this functionality for quite some time now. oh yeah, and boo to beta..
  • The title is misleading. They use accelerators and vehicle speed to navigate. It aint dead reckoning
    • Huh? That's exactly what dead reckoning is. Repeatedly estimating where you are given a known start point, and your direction and speed from there.

      • by FlyingGuy (989135)

        As the poster correctly points out there is a large difference.

        Inertial Navigation is where you have a set of gyro's and accelerometers measuring your movement in 3 dimensions for aircraft and submarines and in two dimensions for land based vehicles, which in turn is used to update your position based upon an initial position fix ( or in this case the last fix from the GPS ).

        Dead Reckoning is simply, "I have been going on course 213 for the last three hours at 5 knots so I must be here." The difference is

        • You raise the topic of gyros, when they are not mentioned in TFS or TFA. So forget that.

          Accelerometers simply enable the estimated speed and direction to be kept up to date. And using that to update position is dead reckoning, as we have both described.

          Finally the company themselves call the product 3D Automotive Dead Reckoning. So how the fuck can the summary title be wrong? You think you know what their technology is better than the company do themselves?

          • by FlyingGuy (989135)

            Accelerometers simply enable the estimated speed and direction to be kept up to date. And using that to update position is dead reckoning, as we have both described.

            But that is not DR since those accelerometers can account for set and drift, and by definition that is inertial navigation. DR is simply I am at point X NOW and if I go in a direction for n amount of time at a given speed I will be at point Y. There is no interpositional correction.

            As a pilot I frequently fly without a GPS, hence to better understand my position ( other then looking down at the ground and matching features to a chart ) I rely on reports of wind speed and direction at various altitudes to

            • But that is not DR since those accelerometers can account for set and drift, and by definition that is inertial navigation.

              Again, inertial navigation uses gyros. This doesn't.

              And since you are quoting from Wiki:
              "An inertial navigation system (INS) is a navigation aid that uses a computer, motion sensors (accelerometers) and rotation sensors (gyroscopes) to continuously calculate via dead reckoning the position, orientation, and velocity (direction and speed of movement) of a moving object without the need for external references."

              a) Gyros required.
              b) Even Inertial Nav is a form of dead reckoning.

              As a pilot

              ...you are misapplying what you

        • If it looses contact with the satellite it is pretty much just plain lost, now throw in a fairly accurate gyro and set of accelerometers and when the satellite signal goes bye bye you flip over to inertial navigation which can be made pretty accurate since given the fact that cars generally stay on known roads you can then perform path inference based upon the on board map so that if the inertial system seems to think you are driving through a building the system can correct itself by looking at where it has been and put you position back on the road where you should be.

          Correct in principle, but drift will kill your signal within a few seconds when you rely on the current crop of MEMS for this. Remember, you need to integrate *twice* to get from acceleration to position, and any noise will grow the position error exponentially. If you go with aircraft grade accels, be prepared to spend more than the price of your car for a decent system. This will be precise enough to keep you on track for a few hours, but don't expect this to be part of your next car's nav system anytime

  • by Jaktar (975138) on Saturday February 08, 2014 @11:24AM (#46195667)

    Contrary to the assertion in the story, I've never been there.

  • by gnasher719 (869701) on Saturday February 08, 2014 @11:27AM (#46195679)
    Don't know who well it works, but there was a demo by Apple's iOS developers where they combine GPS and WiFi. In towns with large buildings and awful GPS reception you will usually have tons of WiFi signals around, so at least in principle it should be possible to improve navigation using both.
    • by Rich0 (548339)

      Android has been doing this for eons. Why do you think they were snooping for isids when they did all the street view passes?

      • Android has been doing this for eons.

        So what? The poster didn't say Android didn't do it.

        But as to which did it first, that was iOS. How do I know? Because iOS was using Skyhook Wireless for location in the very first iPhone. And iPhone launched before any Android devices.

        • But as to which did it first, that was iOS. How do I know? Because iOS was using Skyhook Wireless for location in the very first iPhone. And iPhone launched before any Android devices.

          The trick is actually to use both GPS _and_ WiFi. In most places, GPS should be a lot more accurate. Except in towns, where you have (a) huge buildings making GPS suffer, but at the same time (b) lots of WiFi signals so you can probably average out the inaccurate data from them. With a bit of maths you could probably use change in signal strength to improve things if you receive multiple WiFi signals.

          • The trick is actually to use both GPS _and_ WiFi.

            For sure. And that came in the iPhone 3G. And I've just checked, and that also predated all Android phones.

  • A few months ago I left work to run some errands and stuck my Android phone in its car charging dock (which automatically activated my preferred nav program). Six or seven miles down the road I noticed the icon representing my car was different than normal and my location was about a half-block off my actual position. At the next stoplight I checked and discovered my GPS was turned off. My phone had reasonably calculated my position through several turns and stops using only the accelerometer (dead-reckonin

    • by mtippett (110279)

      Maybe. Let's break it down - Phones vs Cars...

      Phones have Location Based Services (LBS) on a typical phone also uses wifi, GPS and Cell Tower location. A request to LBS expects should return a reasonable fix to the highest accuracy. In a dense urban environment, there is a lot of information from wifi/Cell to give a good fix - probably better than GPS. They have a magnetometer that is affected by materials around them and is not guaranteed to be aligned in a consistent way to the movement. In a dock,

  • Being a Sprint customer?

  • The automotive nav system I work on has 2D dead reckoning, relying on GPS for altitude. 3D dead reckoning is news to me, and I suspect is the intended newsworthy bit here. When GPS fails and the digital terrain model doesn't account for urban landscapes like parking garages, both above and below ground, and tunnels, positioning is calculated in software. It's an expensive, imperfect process I imagine can at least be offloaded to sensors, if not improved, as possibly done in this chip. That would certainly f
  • Yep, my 2001 Acura has it too. They use wheel sensor data for speed and a gyro compass for azimuth. It works very well.
  • A GPS which receives speed, wheel position and reverse light data from the car does dead reckoning. I watched a friend's car do it just this weekend as we drove into an underground parking garage where you get no GPS reception.

    Dead reckoning for car NAVs has been around forever, it actually predates GPS. The first in-car NAV systems by Etak were made using only maps and dead reckoning because GPS didn't exist yet. It also predated affordable LCD panels.

    Before accelerometers and gyros were cheap Garmin even

  • Nuclear submarines [wikipedia.org] use them too! :-)

  • by DoofusOfDeath (636671) on Saturday February 08, 2014 @03:14PM (#46197423)

    It's probably too late to turn back the clock on this, but it's actually spelled "ded" reckoning. Short for "DEDuced".

  • When I worked for Navman we developed some of the first consumer in car navigation systems. We looked at this technology around 2002. Nothing new here...
  • Dead reckoning technology is actually very old. It has been used to guide missiles, submarines, and of course cars for decades even before the GPS was invented. It is the technology used by sailors before they had GPS as well. The idea is simple and complex at the same time: use some specific known reference, guess what's happening in the absence of reference, and recalibrate once a new reference becomes available again . References can be the sun, stars, towns, or GPS itself.

    In car dead reckoning, in contr

  • We've all been there. You're relying on your vehicle's built-in navigation system to get to that meeting downtown,

    Errr, no.

    What is the usage case again?

    You're in a concrete canyon downtown. So what the fuck are you doing driving? That's what taxis and tube trains and buses are for. Cars in the city centre are almost always a guarantee for frustration and delay.

    Besides, if it's your own city, how on earth can you exist without knowing it at least as well as the Sat Nav, and also knowing the pedestrian-onl

  • One word, Etak.

    Dead reckoning automotive navigation predates GPS and predates what would have become Geostar. Sure, the hardware is cheaper now, and algorithms might be better, but there's nothing new about this concept. Welcomed? Sure. But don't pretend it's a new idea.

  • Car electronics are perpetually shit, out of date, and overpriced. Put the feature on my phone I don't care if it won't be as accurate.

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