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Dead Reckoning For Your Car Eliminates GPS Dead Zones

timothy posted about 7 months ago | from the walk-30-paces-then-turn-left dept.

Transportation 151

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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My Toyota has had this since 2004... (5, Informative)

Electricity Likes Me (1098643) | about 7 months ago | (#46195305)

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

Re:My Toyota has had this since 2004... (0)

Anonymous Coward | about 7 months ago | (#46195401)

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

The metric system isn't new either, but Americans managed to shit-can the logic that the rest of the world enjoys.

Fuck off (0, Funny)

Anonymous Coward | about 7 months ago | (#46197567)

We love our furlongs, chains, drams, grains, pounds, ounces, cups, gallons, slugs, fortnights, etc. Speaking as an engineer, calculations work just fine in either, but I prefer a system with history and finesse, you uncultured swine!

Re:My Toyota has had this since 2004... (0)

JoeMerchant (803320) | about 7 months ago | (#46195431)

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

Re:My Toyota has had this since 2004... (1)

kheldan (1460303) | about 7 months ago | (#46196979)

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 consumer-level applications, and automobiles are consumer-level, so I'm not so surprised that it's taken this long for someone to step up and close that gap. As a sidebar it's a fairly small gap compared to what it used to be, GPS receivers are amazingly more sensitive than they used to be when companies like Trimble and Garmin were the only games in town, 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.

..and of course, my being properly paranoid, this technology also means that it's going to be that much harder to defeat the GPS in your car so that the government and nosy corporations can't track our every move when driving. I suppose even if you disconnected the antenna, it'd eventually ask you to enter your co-ordinates so D.R. would work, but I suppose you could put in "Barrow, Alaska" or something and let it try to figure out how you're driving across the ocean..

Re: My Toyota has had this since 2004... (2, Informative)

Anonymous Coward | about 7 months ago | (#46195463)

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.

Re:My Toyota has had this since 2004... (1)

Bigger R (131370) | about 7 months ago | (#46195507)

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

Re:My Toyota has had this since 2004... (0)

Bigger R (131370) | about 7 months ago | (#46195523)

Also disappointed in my typo, but it WAS just a Beta comment! :)

Re:My Toyota has had this since 2004... (2)

AmiMoJo (196126) | about 7 months ago | (#46195531)

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.

Re:My Toyota has had this since 2004... (1)

BasilBrush (643681) | about 7 months ago | (#46195789)

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.

Re:My Toyota has had this since 2004... (1)

Bing Tsher E (943915) | about 7 months ago | (#46196301)

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.

Re:My Toyota has had this since 2004... (2)

Grishnakh (216268) | about 7 months ago | (#46196731)

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 garage with a GPS-only device). The problem with in-car nav systems is that they usually have very out-of-date technology otherwise, the maps aren't updated, you have to pay a fortune for updated maps, etc.

Re:My Toyota has had this since 2004... (1)

michelcolman (1208008) | about 7 months ago | (#46196901)

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.

Re:My Toyota has had this since 2004... (1)

Grishnakh (216268) | about 7 months ago | (#46197045)

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.

Re:My Toyota has had this since 2004... (1)

jtara (133429) | about 7 months ago | (#46197813)

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 using a previously determined position, or fix, and advancing that position based upon known or estimated speeds over elapsed time and course."

But we can do better than that, today, and there are a number of sensors that - with the right math - can be "fused" to provide a more accurate estimate of position than would be possible using any one. GPS, then, is just one potential input.

Wikipedia gives a very broad definition, as this isn't just applied to navigation:

"Sensor fusion is the combining of sensory data or data derived from sensory data from disparate sources such that the resulting information is in some sense better than would be possible when these sources were used individually. The term better in this case can mean more accurate, more complete, or more dependable, or refer to the result of an emerging view, such as stereoscopic vision (calculation of depth information by combining two-dimensional images from two cameras at slightly different viewpoints)."

Phones today typically have GPS, accelerometer, magnetometer, and gyro sensors. While additional inputs such as auto speedometer (not very accurate, though, by law only required to be +- 1.5% or so) and wheel sensors might be useful, they certainly aren't required.

I'd assume that major navigation apps already do this, probably using Kalman Filtering:

http://www.cs.unc.edu/~welch/k... [unc.edu]

http://en.wikipedia.org/wiki/K... [wikipedia.org]

So, this is nothing new. But, then again - there's no claim that it is. (Just the incorrect reading between the lines here...) They've just conveniently put the needed sensors and a means of performing the calculations in a single chip.

You know, just like Apple did for the iPhone 5S...

Re:My Toyota has had this since 2004... (1)

DeathToBill (601486) | about 7 months ago | (#46196855)

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.

Re: My Toyota has had this since 2004... (1)

Balthisar (649688) | about 7 months ago | (#46195663)

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

Re: My Toyota has had this since 2004... (1)

ebno-10db (1459097) | about 7 months ago | (#46195869)

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.

Got you all beat... (0)

Anonymous Coward | about 7 months ago | (#46196005)

We used dead reckoning in the early 1980s to fill in for missing GPS satellites before all of them were even in orbit.

The PROBLEM that exists, is error rates. Once on dead reckoning, the error grows from a few inches to a few feet within seconds. This is not a problem for ocean going ships... But a severe problem for cars.

Use of accelerometers is only to reduce the error. Unfortunately, accelerometers can be wrong - due to rotation, deceleration, and acceleration when there is no feedback on WHAT is causing the readings. Especially when due to vibration. Anything that is a multiple of the sampling frequency causes erroneous readings - and can make it appear that a vehicle is moving in one direction... but due to sampling error, misses the reverse.

Re:Got you all beat... (2)

K. S. Kyosuke (729550) | about 7 months ago | (#46196197)

Use of accelerometers is only to reduce the error. Unfortunately, accelerometers can be wrong - due to rotation, deceleration, and acceleration when there is no feedback on WHAT is causing the readings

Cars don't fly. As long as you have traction, measuring distance shouldn't be a problem (especially if you supplement wheel axle sensors with an optical device similar to modern computer mice, to compensate for the tire pressure, and integrate the data). Unlike with airplanes and ICBMs, you shouldn't need precise acceleration from the accelerometers, vehicle orientation along the three axes is what you need. Direct distance measurements obviate the need for double integration (but are impossible in subs, airplanes, and spacecrafts, unlike in cars).

Re:Got you all beat... (2)

Grishnakh (216268) | about 7 months ago | (#46196767)

You don't even need to go to all that trouble. That kind of accuracy simply isn't necessary in a car as long as it has GPS. Dead-reckoning, in an in-car navigation system, is only needed to make up for the inaccuracy with GPS, which is mainly because you sometimes lose the signals (inside a parking garage, around too many tall buildings, etc.). You don't normally lose GPS signals for a very long amount of time, only short periods. So DR is just a supplement, and the vehicle's odometer signal alone is enough for supplementation, and an electronic compass signal is even better because this gives you direction, in case you turn the car while your GPS signal is missing. You're not looking for accuracy to the inch or even the foot, 50-foot accuracy is good enough in this application, so compensating for tire pressure is entirely unnecessary; they don't do that for the vehicle's odometer after all. You just need the system to warn you in enough time for you to make the next turn.

Re:Got you all beat... (1)

natron3030 (3530211) | about 7 months ago | (#46197357)

Without good DR you don't have to lose a GPS signal in a large city for a nav system's positioning to utterly fail. An Urban Canyoning effect can render GPS unreliable despite a strong signal. I've seen GPS in a mile long urban canyon position a vehicle in and across a parallel river in the middle of the canyon. The ultimate solution when this behavior is detected is to rely solely on DR, which in practice can go days of driving before being significantly inaccurate.

Re:Got you all beat... (1)

Grishnakh (216268) | about 7 months ago | (#46197513)

Surely you can use both, even if your DR data is not so great; just use the DR data to verify the GPS data makes sense. If the GPS signals say the vehicle has suddenly teleported into a river, check that against the DR. If the DR data says you're still driving straight, then disregard the GPS data until it agrees with the DR data.

Re:My Toyota has had this since 2004... (0)

Anonymous Coward | about 7 months ago | (#46195831)

Indeed. A buddy of mine had this in his '01 Ford Mondeo (I think it was a VDO Dayton unit - cost a pretty penny back then.. Good thing it was a company car).

Re:My Toyota has had this since 2004... (5, Funny)

GoChickenFat (743372) | about 7 months ago | (#46195841)

My car has had this since I started to drive. It's called "using my brain".

Re:My Toyota has had this since 2004... (0)

Anonymous Coward | about 7 months ago | (#46196079)

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

I trust a road atlas and local maps over GPS.

Re:My Toyota has had this since 2004... (0)

Anonymous Coward | about 7 months ago | (#46196299)

Most, if not all, GPS units have maps as a primary feature, and unlike paper maps you will likely have one of the most recent, up-to-date versions already on there, rather than one thats 10+ years old, at least for most towns and cities. They're read just the same, and can even zoom in or out for long road trips or navigating a town without having to have a whole book or wad of maps; paper maps are only better when it comes to the power issue.

But the fact remains that if you need turn-by-turn directions to get where you're going you're probably too fucking stupid to be driving, and its kind of shocking that you're smart enough to know how to breathe.

Re:My Toyota has had this since 2004... (1)

K. S. Kyosuke (729550) | about 7 months ago | (#46196135)

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).

Re:My Toyota has had this since 2004... (1)

Razgorov Prikazka (1699498) | about 7 months ago | (#46196413)

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

Re:My Toyota has had this since 2004... (2)

K. S. Kyosuke (729550) | about 7 months ago | (#46196503)

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.

This was required before the end of SA! (1)

Terje Mathisen (128806) | about 7 months ago | (#46196667)

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 odometers, so that differences in tire type & pressure is automatically compensated for.

Using a barometer you can do the same for altitude, automatically compensating for changes in local air pressure.

Terje

Fuck Beta (0, Offtopic)

Anonymous Coward | about 7 months ago | (#46195315)

Catch all placeholder.

I work for an automotive telematic unit supplier.. (0)

Anonymous Coward | about 7 months ago | (#46195319)

.. and we've had 2D dead reckoning for YEARS, across many different OEMs... and it's still not always perfect (in under water tunnels, for example)

but why 3D? Do you really care which level of the parking garage you're driving on?

Re:I work for an automotive telematic unit supplie (2)

dreamchaser (49529) | about 7 months ago | (#46195527)

Why 3D? Because GPS provides your elevation and uses that as well as your XY coordinates to determine where you are, trip time, etc.

Re:I work for an automotive telematic unit supplie (1)

K. S. Kyosuke (729550) | about 7 months ago | (#46196247)

GPS elevation measurements are notoriously problematic unless you have survey-class equipment. (I also wonder how many map application programmers can actually work with WGS84 elevation data.)

Re:I work for an automotive telematic unit supplie (1)

Opportunist (166417) | about 7 months ago | (#46195725)

Believe me, when your GPS tells you to go straight ahead because that's where the exit is but you're still on the 6th floor, yes, you definitely do!

Re:I work for an automotive telematic unit supplie (1)

gottabeme (590848) | about 7 months ago | (#46195845)

Who would use GPS to navigate inside a parking garage?

Re:I work for an automotive telematic unit supplie (1)

JustOK (667959) | about 7 months ago | (#46196161)

People that need to use a GPS inside a parking garage, for one.

Re:I work for an automotive telematic unit supplie (2)

K. S. Kyosuke (729550) | about 7 months ago | (#46196261)

A self-driving car? (In conjunction with other sensors, I assume.)

Re:I work for an automotive telematic unit supplie (0)

Anonymous Coward | about 7 months ago | (#46196285)

People who couldn't find their way out of a parking garage if the exits had signs and there were arrows on the floor leading them in the right direction. Basically people with the same level of intelligence as those who are pushing the Beta of this very site.

Re:I work for an automotive telematic unit supplie (1)

gnasher719 (869701) | about 7 months ago | (#46196745)

Who would use GPS to navigate inside a parking garage?

Not to navigate, hopefully. But in a large parking garage that you don't know well, it would be useful to be able to use GPS to remember where your car is and find it again.

Re:I work for an automotive telematic unit supplie (2)

fisted (2295862) | about 7 months ago | (#46197559)

I can only see one possible outcome of that. -- "Uh, where was my car again?" - (checks GPS) - "Oh, right, it's still right under my butt, duh."

Re:I work for an automotive telematic unit supplie (1)

CityZen (464761) | about 7 months ago | (#46197371)

Why 3D? Because some places have lots of elevated highways (as well as parallel roads underneath them).

But mostly because GPS works in 3D, and re-acquiring the signal is faster the more accurate the 3D estimated location is.

don't think this really works on phones yet (5, Interesting)

Trepidity (597) | about 7 months ago | (#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.

Re:don't think this really works on phones yet (1)

drinkypoo (153816) | about 7 months ago | (#46195473)

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.

Re:don't think this really works on phones yet (1)

AmiMoJo (196126) | about 7 months ago | (#46195563)

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.

Re:don't think this really works on phones yet (1)

BasilBrush (643681) | about 7 months ago | (#46195829)

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.

Re:don't think this really works on phones yet (1)

aix tom (902140) | about 7 months ago | (#46197369)

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.

Re:don't think this really works on phones yet (1)

kipsate (314423) | about 7 months ago | (#46195995)

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.

Actually it does (1)

Arker (91948) | about 7 months ago | (#46196027)

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 concept certainly is not.

Re:Actually it does (1)

BasilBrush (643681) | about 7 months ago | (#46196085)

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.

My BMW have beta retard system (-1, Troll)

Anonymous Coward | about 7 months ago | (#46195337)

WTF you post so frequently, do you have hamsters running in your department? Or are the post don't look like they are on topic?

FUCK the BETA and fuck new slashdot

many moons ago (1)

bferrell (253291) | about 7 months ago | (#46195343)

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

Re:many moons ago (1)

kamakazi (74641) | about 7 months ago | (#46195857)

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 city.

It is a wonderfully elegant solution, since it predated public availability of GPS systems and had no external dependancies. It was also delightful in that it was an exact computer analog of nautical navigation since the discovery of the compass and knots on a rope.

Re:many moons ago (1)

mrbester (200927) | about 7 months ago | (#46195893)

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

Re:many moons ago (0)

Anonymous Coward | about 7 months ago | (#46196365)

If this is basically the same story I saw months ago, the actual story is that they've managed to shrink the whole system down to microchip size.

I reckon either Slashdot or Beta is dead (-1, Offtopic)

runeghost (2509522) | about 7 months ago | (#46195355)

Please post this to new articles if it hasn't been posted yet.

On February 5, 2014, Slashdot announced through a javascript popup that they are starting to "move in to" the new Slashdot Beta design.

Slashdot Beta is a trend-following attempt to give Slashdot a fresh look, an approach that has led to less space for text and an abandonment of the traditional Slashdot look. Much worse than that, Slashdot Beta fundamentally breaks [reddit.com] the classic Slashdot discussion and moderation system. If you haven't seen Slashdot Beta already, open this [slashdot.org] ] in a new tab. After seeing that, click here [slashdot.org] to return to classic Slashdot.

We should boycott stories and only discuss the abomination that is Slashdot Beta until Dice abandons the project.

We should boycott slashdot entirely during the week of Feb 10 to Feb 17 as part of the wider slashcott [slashdot.org] Moderators - only spend mod points on comments that discuss Beta Commentors - only discuss Beta http://slashdot.org/recent [slashdot.org] - Vote up the Fuck Beta stories

Keep this up for a few days and we may finally get the PHBs attention. Links of note: Discussion of Beta: http://slashdot.org/firehose.p... [slashdot.org] Discussion of where to go if Beta goes live: http://slashdot.org/firehose.p... [slashdot.org] Alternative Slashdot: altslashdot.org [altslashdot.org] IRC Discussion: freenode #slashdot-refugees

Re:I reckon either Slashdot or Beta is dead (1, Insightful)

Somebody Is Using My (985418) | about 7 months ago | (#46195415)

Don't forget nntp://comp.misc [comp.misc] on Usenet
(although I doubt there are any modern browsers that support the nntp:// [nntp] protocol* anymore so you will have to join mainly by downloading a free usenet client, sign up to eternal-september.org and adding comp.misc to your subscribed newsgroup list)

Still, if people are willing to use old school IRC then Usenet isn't much worse ;-)

* similar to PIN number

Hey... (-1, Flamebait)

Anonymous Coward | about 7 months ago | (#46195367)

Go away beta, nobody likes you.

Adios! (0)

Anonymous Coward | about 7 months ago | (#46195385)

"The Company's net loss for the quarter ended December 31, 2013 totaled approximately $5.9 million, resulting in diluted loss per share of $0.11. [...] Slashdot Media was acquired to provide content and services that are important to technology professionals in their everyday work lives and to leverage that reach into the global technology community benefiting user engagement on the Dice.com site. The expected benefits have started to be realized at Dice.com. However, advertising revenue has declined over the past year and there is no improvement expected in the future financial performance of Slashdot Media's underlying advertising business. Therefore, $7.2 million of intangible assets and $6.3 million of goodwill related to Slashdot Media were reduced to zero."

Fork /.

Dice Holdings, Inc. (1)

Anonymous Coward | about 7 months ago | (#46195411)

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

Fork or die.

Re:Dice Holdings, Inc. (1)

Bing Tsher E (943915) | about 7 months ago | (#46196387)

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.

prius GPS has had that for ages (1)

Win Hill (1594463) | about 7 months ago | (#46195419)

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.

Not with a bang, but with a Beta. (1, Offtopic)

emmagsachs (1024119) | about 7 months ago | (#46195437)

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 ears, and will continue to do so. Dice intends to dispose of Classic in favor of Beta [slashdot.org] , whether we like it or not. Do you know how to tell whether an executive really cares about feedback? If her CV [linkedin.com] doesn't proclaim the following "successes":

Proven track record innovating and improving iconic websites (CNET.com, Dice.com, Slashdot.org, Sourceforge.net) while protecting their voice and brand integrity

Classic for your Beta Eliminates Screen Dead Zones (-1, Flamebait)

Anonymous Coward | about 7 months ago | (#46195487)

Please, stop posting meaningful comments. Your post of today is killing the Slashdot of tomorrow.

FUCK DICE, FUCK BETA.

Good for Priavacy? (0)

Anonymous Coward | about 7 months ago | (#46195491)

Correct me if I'm wrong, but wouldn't a GPS (or, Localized Positioning System?) that doesn't need to connect to a network be good for privacy? If it is, that could be a good marketing angle.

Welcome to 2000 !!! (2, Interesting)

thygate (1590197) | about 7 months ago | (#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..

Inertial Navigation - not dead reckoning (2)

marcgvky (949079) | about 7 months ago | (#46195515)

The title is misleading. They use accelerators and vehicle speed to navigate. It aint dead reckoning

Re:Inertial Navigation - not dead reckoning (0)

Anonymous Coward | about 7 months ago | (#46195761)

Concur! Couldn't have said it better myself.

Re:Inertial Navigation - not dead reckoning (1)

BasilBrush (643681) | about 7 months ago | (#46195861)

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.

Re:Inertial Navigation - not dead reckoning (1)

FlyingGuy (989135) | about 7 months ago | (#46196047)

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 that the DR cannot take into account set and drift and the accuracy of speed measurement is quite important.

OK, now lets take a cars NAV system. If it is a typical device it is has pretty much the entire road map loaded as a set of links and nodes with background tiles that are pre-rendered for the given zoom levels it is designed to support. 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.

So the summary is quite miss leading because the editor does not know the difference or the sales weenie from the company thought that "Dead Reckoning" sounded cool.

Re:Inertial Navigation - not dead reckoning (1)

BasilBrush (643681) | about 7 months ago | (#46196153)

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?

Re:Inertial Navigation - not dead reckoning (1)

FlyingGuy (989135) | about 7 months ago | (#46196665)

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 change my course so that it is a vector of those winds to arrive at a given point.

From Wikipedia on Automotive Dead Reckoning...

Dead reckoning is today implemented in some high-end automotive navigation systems in order to overcome the limitations of GPS/GNSS technology alone. Satellite microwave signals are unavailable in parking garages and tunnels, and often severely degraded in urban canyons and near trees due to blocked lines of sight to the satellites or multipath propagation. In a dead-reckoning navigation system, the car is equipped with sensors that know the wheel diameter and record wheel rotations and steering direction. These sensors are often already present in cars for other purposes (anti-lock braking system, electronic stability control) and can be read by the navigation system from the controller-area network bus. The navigation system then uses a Kalman filter to integrate the always-available sensor data with the accurate but occasionally unavailable position information from the satellite data into a combined position fix.

This is in principle not inertial navigation, but then again it is not DR in the truest sense of the phrase as it was recognized in navigation. We can call it something else, we can call it lots of things but it is not, imho, DR because the the nav system in the car is constantly updating a position based upon speed and direction of travel. This is a hybrid of inertial and DR so call it something else, just don't call it DR because the cars system is trying to obtain a fix ever second or so. I think it is great that they are trying to do these things, but I also value calling something what it is and not something that it is not.

Re:Inertial Navigation - not dead reckoning (1)

Aviation Pete (252403) | about 7 months ago | (#46196459)

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 soon. DARPA is looking into improved MEMS for this, but it will take many years before this trickles down to a consumer nav system.

to the contrary (4, Funny)

Jaktar (975138) | about 7 months ago | (#46195667)

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

GPS + WiFi (2)

gnasher719 (869701) | about 7 months ago | (#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.

Re:GPS + WiFi (1)

Rich0 (548339) | about 7 months ago | (#46196109)

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

Re:GPS + WiFi (1)

BasilBrush (643681) | about 7 months ago | (#46196239)

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.

Re:GPS + WiFi (0)

Bing Tsher E (943915) | about 7 months ago | (#46196403)

Does your vibrating buttplug run iOS, or just the app on your phone that controls it?

Re:GPS + WiFi (1)

gnasher719 (869701) | about 7 months ago | (#46196797)

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.

Just give it a fancy name... (1)

jennatalia (2684459) | about 7 months ago | (#46195689)

True, this isn't new, but highlighting this fact for every car and improving the technology can make things better for consumers. Aircraft systems have been using it for many years. It would be better if the car had another type of location reference other than GPS, though. Implanting cell tower recognition and interrogation for triangulation would be a way, but would probably require a lot of coordination between the auto industry and FCC.

What's the point? (0)

Anonymous Coward | about 7 months ago | (#46195693)

Our brains have had dead reckoning since the dawn of time. Pilots use it every day. What ever happened to opening up a map and figuring it out for ourselves? Anybody remember Thomas Bros? I'm not in any way against technology, but seriously...if the GPS goes out, figure it out yourself.

http://www.bostonglobe.com/ideas/2013/08/17/our-brains-pay-price-for-gps/d2Tnvo4hiWjuybid5UhQVO/story.html

Just sayin'...

SLASHDOT AS YOU KNEW IT IS FINISHED (-1)

Anonymous Coward | about 7 months ago | (#46195711)

IT IS OVER.....One look at the slashdotmedia.com webpage will confirm that for you.
If you cannot stomach the BETA redsign, if you really love the classic site layout so much, YOU MUST fork the site code and start another site such as what "AltSlashdot" are attempting to do....no if's or but's about this anymore !!!!! Personally speaking, I think it may be a good idea if Joel Spolsky (co-founder of StackOverflow) got involved.

Re:SLASHDOT AS YOU KNEW IT IS FINISHED (1)

maxwell demon (590494) | about 7 months ago | (#46195773)

Yeah sure, we need several million Slashdot clones ... ;-)

My phone already does this. (1)

Telecommando (513768) | about 7 months ago | (#46195815)

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-reckoning). At the time I was impressed.

Re:My phone already does this. (2)

mtippett (110279) | about 7 months ago | (#46196227)

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, it is insulated somewhat and can be compensated.

Cars have wheels that are stuck to the ground and provide a good distance measuring tool - everyone has probably seen a dedicated GPS. They have a fixed magnetometer that is well protected from interference and is fixed relative to the vehicles direction of travel.

Both can align to roads on a map, so you have a correction factor in the roads. Any good nav system will lock onto the roads.

So Cars probably already have a higher probability of tracking reasonable well as is (I've never had the problem described except in hills under dense tree cover). Phones have some better LBS capability. Adding the sensors to the cars, and having a wifi/cell phone lookup capability (live or otherwise) would probably give cars a solid edge. This story seems to be more adware for eyeballs, but may have some merit.

Are you calling everyone stupid? (0)

Anonymous Coward | about 7 months ago | (#46195825)

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

"We've all been there. You send the money to the Nigerian prince so that he can finally pay the transfer fee to send you his ten million dollars." Seriously, you said something equivalent, but the context made it sound like you weren't joking.

As far as is possible for a generalization on the Internet, that's kind of insulting, don't you think? Nobody is really that stupid, except for the kind of people you read about in Darwin Awards.

Using interactive computer maps: sure! Relying on them, and not already knowing where you're going in advance? Please, please tell me there isn't someone who does that, yet is old enough to know how to type sentences into Slashdot forms. If I do happen to be addressing such a person: no, I haven't "been there," and yes, I am calling you a fucking moron who I never want to have anything to do with, because I have no illusions that such magnitude of idiocy could be contained to a single personality quirk: I know you ooze imbecility from every part of your personality. You're an embarrassment to the human race, and we won't miss you when you're gone.

Fundamentals (0)

Anonymous Coward | about 7 months ago | (#46195973)

One of the first things any student pilot learns is to stop looking at the GPS and start looking out the fucking window. This principle is just as valid for driving a car. The GPS is not the terrain, and neither is a paper map. Pull your head out of your ass and start using it.

paper maps? (0)

Anonymous Coward | about 7 months ago | (#46196121)

i must be the only person who uses paper maps, a compass and triangulation of known landmarks. seriously, i use a compass inside a car. it works 99% of the time unless i am near a strong electromagnetic field or a ferromagnetic metal like iron.

Re: paper maps? (0)

Anonymous Coward | about 7 months ago | (#46196445)

Did you know that a modern GPS has a map, a compass, and tells you where you are as well as where you've been?

You don't have to use their navigation to use a GPS the same way you use a map, but you have to take time to plot your course and some people sadly have problems with that.

Putting a real map in their hands doesn't even fix THAT problem.

Is there a fix for (1)

gelfling (6534) | about 7 months ago | (#46196183)

Being a Sprint customer?

3D DR is news to me (1)

natron3030 (3530211) | about 7 months ago | (#46196321)

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 free up the radio to provide more accurate positioning and guidance quicker.

Old technology (1)

technical_maven (2756487) | about 7 months ago | (#46196357)

Yep, my 2001 Acura has it too. They use wheel sensor data for speed and a gyro compass for azimuth. It works very well.

aftermarket units already solved this years ago... (0)

Anonymous Coward | about 7 months ago | (#46196439)

They've tied into the vehicle VSS and have gyros built in to help with issues like this (and it works rather well)

cars do have dead reckoning (1)

YesIAmAScript (886271) | about 7 months ago | (#46196593)

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 made add-on GPSes for cars which required installation so the NAV could get speedometer data and reverse light data so it could dead reckon your position.

http://en.wikipedia.org/wiki/E... [wikipedia.org]

Inertial Navigation. Cool! (1)

Lisias (447563) | about 7 months ago | (#46196839)

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

"ded", not "dead" (2)

DoofusOfDeath (636671) | about 7 months ago | (#46197423)

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

Automotive Dead Wreckoning (0)

Anonymous Coward | about 7 months ago | (#46197543)

Something queasy about the way this product is spelled...

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