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DARPA Develops Non-GPS Navigation Chip
Zothecula writes "The Global Positioning System (GPS) has proved a boon for those with a bad sense of direction, but the satellite-based system isn't without its shortcomings. Something as simple as going indoors or entering a tunnel can render the system useless. That might be inconvenient for civilians, but it's potentially disastrous to military users, for whom the system was originally built. DARPA is addressing such concerns with the development of a self-sufficient navigation system that can aid navigation when GPS is temporarily unavailable."
Embedded car GPS systems are linked to the car speed data, and when entering a long tunnel, will continue to move the position correctly.
For this limited scenario, it appears to the user as if the GPS was active all along.
It wouldn't be disastrous for military applications, because military navigators are all trained on how to navigate without GPS. And they practice it. Also, does anyone lose their way going into a tunnel? Maybe a mining complex or caves or something....
It works by have six-axis, extremely sensitive, gyroscopes and accelerometers. Thus it can extrapolate position within a margin of error, hopefully long enough to get back in range of GPS.
"First they came for the slanderers and i said nothing."
What the article is describing (an IMU) have been around forever (since before GPS), and pretty much any system that uses GPS for navigation has one to supplement the GPS. What is new here is the size; a full IMU on a single chip the size of your pinky finger nail. Pretty cool considering that not too long ago these used to comprise of multiple separate physical devices (gyrometer x3, accellerometer x3, magnetometer), but have been getting progressively smaller over the years. MEMs has come a long way.
nothing new about gyroscopes and accelerometers in a package, even an integrated circuit one.....this might be smaller or perhaps more accurate than some I've seen over the DECADES. but definitely no new tech or ideas here.
http://en.wikipedia.org/wiki/Inertial_navigation_system There are even a whole bunch of ways to build them.
Go to an average mall nowadays and ask yourself it that's true. ;-)
Lost at C:>. Found at C.
The story here is they made a really small INU & timing module. AHRS/IMU/INU (among other acronyms) have been around for a very long time. This is simply a very, very, small one, that is probably cheaper to produce than exsiting MEMS systems. Of course, it won't have the accuracy of the larger systems, but that's part of the trade offs.
if you are indoors you probably know where you are
Says the man who never travels. Try out your theory in an airport or major mall. Heck, I would love indoor navigation for some medical complexes.
Smart but misguided, one might say ...
Bent, folded, spindled, and mutilated.
if you go into a tunnel, you will come out and get the signal again. and its not like you need to navitage inside a tunnel.
Not all tunnels have only one entry and exit point. I already missed an exit in the tunnels under Brussels on a couple of occasions. And even if all tunnels were simple one-pipe affairs... What if you need to make a turn shortly after the tunnel, and your GPS takes too long to get a fix so it still has you at the tunnel's entrance when you blissfully sail past your turn?
I'm not saying we couldn't cope without these improvements, as indeed in the past we managed to do just fine without GPS. But there's room for useful improvement nonetheless.
Install windows on my workstation? You crazy? Got any idea how much I paid for the damn thing?
So when can I get these at digikey?
As others have posted, intertial nav platforms have been around for decades -- in military aircraft, and then in commercial aircraft.
The break throughs are not only in getting the platform sensors, the gyros, accelerometers, and magnetometers, onto a single chip, but also in being able to provide the computer horsepower to do the Kalman filtering to integrate all these sensors to come out with a nav/position solution, in a few cubic centimeters of processed sand, and for a few Watts.
It's not just the sensors, it's the processing as well. The sensors just throw data at you (data with all sorts of errors); the Kalman filter lets you bring everything together for your nav/position solution. As a prof long ago said it, "Kalman filtering -- how to stop worrying and learn to love matrix inversion."
Missiles have had inertial navigation systems for some time now. Where's the advance that brings this technology to regular consumers?
DC8 jets had inertial navigation systems back in the '60s. You could fly from LAX to Tokyo without touching the controls and the plane would only be a few hundred yards off alignment from the runway. Not bad for a 5000+ mile flight.
They can take my LifeAlert pendant when they pry it from my cold dead fingers.
One major application for this is terminal guidance for munitions, like the Joint Direct Attack Munition and surface-to-ground missiles like the Hellfire. Those need an IMU so they can hit targets with GPS jammers. They get an initial position from the aircraft, which has a better IMU and upward-looking antennas which can probably get GPS despite ground jammers. All the small IMU has to do is keep a good position and heading for about a minute.
As this gets smaller, it becomes usable on more munitions, such as mortar rounds. Eventually, most indirect fire ammo will have this.
in the USA we have A-GPS. the cell towers send out a GPS signal which is a lot faster than the US Air Force one
if you are indoors you probably know where you are
Let me introduce you to the Great White North:
PATH is downtown Toronto's underground walkway linking 28 kilometres of shopping, services and entertainment.
PATH facts:
According to Guinness World Records, PATH is the largest underground shopping complex with 29 km (18 miles) of shopping arcades. It has 371,600 sq. metres (4 million sq. ft) of retail space. In fact, the retail space connected to PATH rivals the West Edmonton Mall in size.
The approximate 1,200 shops and services, such as photocopy shops and shoe repairs, found in PATH, employ about 5,000 people. Once a year, businesses in PATH host the world's largest underground sidewalk sale.
More than 50 buildings/office towers are connected through PATH. Twenty parking garages, five subway stations, two major department stores, six major hotels, and a railway terminal are also accessible through PATH. It also provides links to some of Toronto's major tourist and entertainment attractions such as: the Hockey Hall of Fame, Roy Thomson Hall, Air Canada Centre, Rogers Centre, and the CN Tower. City Hall and Metro Hall are also connected through PATH.
There are more than 125 grade level access points and 60 decision points where a pedestrian has to decide between turning left or right, or continuing straight on. The average size of a connecting link is 20 metres (66 ft.) long by 6 metres (20 ft.) wide.
Signage includes a symbol for people with disabilities whenever there is a flight of stairs ahead.
PATH Facts
Umm, that's not at all how A-GPS works.
http://en.wikipedia.org/wiki/Assisted_GPS
A-GPS works by providing an estimated position and time to the GPS reveiver, along with ephemerides (orbital position/parameters) of the satellites. Together, that the search space of which satellitest to look for, estimates of signal doppler, and estimated position. So you get a faster initial position fix, ie cold-start. Once your GPS has accurate time, position, and lock on multiple satellites, A-GPS provides no more benefits.
The data is not a GPS signal from the towers, it's a data payload, pure and simple. In some systems, the GSM networks provides a special low-latency time hack directly, since A-GPS really needs 1mS accuracy to be maximally useful (1mS = 300km position error) and cellular data latency is much worse than that. Position, ephemeris ans 100ms time is still useful though. Estimated position comes from visible towers and big databases, also many smartphones use WiFi as well.
More to the point, inertial navigation sensors like this are designed to augment Radionavigation systems, either carrying the slack when radio isn't available, or helping provide more precise or refined motion data to keep the GPS's Filterssmooth and accurate
nothing new about gyroscopes and accelerometers in a package, even an integrated circuit one.....this might be smaller or perhaps more accurate than some I've seen over the DECADES. but definitely no new tech or ideas here.
yeah.. the first autopilots worked on those gyro+accel principles.
world was created 5 seconds before this post as it is.
There's a respectably large underground complex in Crystal City, on the south side of Washington DC, though it's not quite Toronto scale. A subway station, a mall with food court, entrances to office buildings, bottom floors of a couple of hotels. I had some business trips where entered the subway at National Airport (briefly above ground) and didn't come out of the tunnels again until I left town. There's an elevator in the complex that tells you what floor you're on which was confused one day (telling me I was one floor below the one I was really on), and unfortunately I didn't have time to take it down to the basement to see what it would say about it.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks