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Technology

Real-Time Collaborative Mapmaking 179

savetz writes "Throughout October and November, citizens of Amsterdam were invited to wear a GPS tracker as they went about their lives. Their whereabouts were forwarded to a server which created a map of the city in real-time, based on "the sheer movements of real people." The site includes aggregate maps, and those created by individuals, including a subway driver, cyclist, and marathon trainer."
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Real-Time Collaborative Mapmaking

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  • you've come a long way baby. next stop....AMERICA!
  • by Scrameustache ( 459504 ) on Monday December 02, 2002 @04:34PM (#4796085) Homepage Journal
    They gave a GPS to a subway driver? What next? GPS maps of deep mineshafts? : )

    • Re:Subway driver? (Score:2, Informative)

      by inteller ( 599544 )
      actually GPS in it's purest form could never map the subway, just places where it went above ground. TO map underground they'd need some sort of OnStar type system that relied on more than just a GPS signal.
    • Re:Subway driver? (Score:2, Informative)

      by CrazyJoel ( 146417 )
      The a lot of the "subway" in Amsterdam is above ground.
      • i thought all of the city transport was above ground, big trolleys with bus drivers that weren't picky if u reused your ticket. heck, even most of the trains were above ground there.

        it really adds all of the charm to almost being run over by something every second on the street :) ring ring! ring ring!

    • How about strapping mini-GPSes to ally cats, or maybe even cockroaches? Better yet, politicians. Could get interesting.....

      Anyhow, as far as I recall, and my memory of Amsterdam is a little hazy (forget why, though), there *are* no subways. The public transport is electric streetcars [hotels-of-amsterdam.org] that kind of look like subways trains, but are much shorter and do not go under the ground. Warning: these things are actually very dangerous as they basically run on the sidewalks, have a tendency to sneak up on you, and need considerable room to stop. Be careful.

      Dan
  • by Brigadier ( 12956 ) on Monday December 02, 2002 @04:36PM (#4796105)


    this reminds me of a story of two guys who at intersections would carry the back wheels of the car over wheel sensors. thus the traffic department would have to account for 64.5 cars passing through the intersections.
    • Were these the guys with the 2.3 kids?

    • by Anonymous Coward
      Great, except traffic counters dont count in .5 cars. If one axle somehow did not trip the air tube, it would show up as one full car short (depending on tube and machine setup).
    • this reminds me of a story of two guys who at intersections would carry the back wheels of the car over wheel sensors. thus the traffic department would have to account for 64.5 cars passing through the intersections.

      I think I'd just drive with two wheels on the sidewalk... but then again I read /. and have no muscles.
    • by devphil ( 51341 ) on Monday December 02, 2002 @04:52PM (#4796258) Homepage


      There's a great scene in Cryptonomicon where he writes about attaching lights to people's heads, then tracking the lights from a side view as they walk on and off street curbs. Graphing over time would produce a square wave, with sidewalks showing up as high lines, and streets as low lines.

      The point is that Waterhouse is one of the kinds of people who could stare at boatloads of those graphs, and then emerge with an extremely detailed street map of London.

    • Or 64 cars and one Segway.
    • What about vehicles with 3, 5, or 7 axles???
    • This would be the case if only cars went passed an particular intersection. In real life, you would have both the sensor, and then a study where people actually do a car count to determine a reasonable ratio for car / truck traffic. Think about it. The sensor is only measuring axle passages. Cars may have two, but trucks can have anywhere from 3 axles up.

      If you ever wonder why there are a number of cars sitting on the grass around intersections or interchanges that is what they are doing.

      It would be a lot more fun to sit at the sensor and go back and forward...
      • It would be a lot more fun to sit at the sensor and go back and forward...

        Oh c'mon, that's what pogo sticks are for! When I was 14 I bounced on one of those pneumatic car-sensor tubes at a dry-cleaner in my neighborhood with a pogo stick... I think the entire staff came out looking for me, and they were carrying big sticks. :-)

        Ah, the good 'ol days....

      • Aaaaah, so the "$4,300 O.B.O" sign in their window is only there to confuse the "Big Brother" naysayers!!!

        I'd been wondering.

        Cause $4,300 (or best offer) for some of those cars is outrageously high!
      • It would be a lot more fun to sit at the sensor and go back and forward...

        Nah, just keep looping around and backing over it. That way some bean counter can get stuck trying to figure how the hell negative 14 cars went through the intersection this month :)

        -
    • Surely it would be easier to hop on the nearest sport bike and do a wheelie over the sensor?

      Of course, any dual axle truck would screw it up as well. Or a heavy unicycle.

      I may also just be over analyzing the joke in which case I apologize.
    • by JaredOfEuropa ( 526365 ) on Monday December 02, 2002 @07:18PM (#4797314) Journal
      Heh, they did something similar over here, when a new system for measuring speed over a stretch of road was introduced. The system would read the license plate at two points a few miles apart, and calculate the speed using the time difference.

      During the test phase, a few guys got two identical Volkwagens and put the license plate of one on the back of the other. They then drove one past one checkpoint and immediately drove the other past the next, clocking a respectable speed of Mach 15 or so. The people looking at the stored photographs thought they were looking at the same car in both pictures and were as puzzled as the system. Probably didn't stop them for sending these guys a speeding ticket anyway *shudders*
      • Probably didn't stop them for sending these guys a speeding ticket anyway *shudders*

        I sure hope the fine wasn't $10 per mile over the speed limit :)

        clocking a respectable speed of Mach 15

        A real fun project would be to try to break light speed....

        ... in reverse!



        -
      • Step 1: Print 2 identical numberplates onto paper.
        Step 2: Hold first numberplate to speed camera on the A1
        Step 3: A friend holds the second number plate to the next speed camera.

        Adjust timing to a "believable" level, somewhere around 150mph. Wander around your competitors' carpark to gather numberplates to use...
  • I'd spell out "PWND" by walking in the correct pattern!
  • This is a great idea! If only my country could embed a chip inside of me and everyone in the U.S., then we can bring spam to a whole new level!!!
    • This is a great idea! If only my country could embed a chip inside of me and everyone in the U.S., then we can bring spam to a whole new level!!!

      Let me get this straight. You want a subcutaneous chip that will turn yours and everybody else's brains into spiced pork and ham?
    • Every public wall and floor is a continuous video advertisement in Spielberg's 2002 movie "Minority Report". It is keyed into the biometrics of the passerby. No special chip needed.
  • by steveadept ( 545416 ) on Monday December 02, 2002 @04:37PM (#4796122)
    Okay, it may seem a funny jumping-off point, but stick with me for a second. Digital society hates spam, but not nearly enough for anything to actually be done about it. I think that's because it's basically limited to doing damage to your Inbox.

    Yet when everybody's walking around with wristwatches connected to GPS and the 'net, and Joe's Pizza and Meg's Jewelry and Walmart and Target all want to spam your watch with their current specials as you walk within a hundred feet of their stores, people would (I hope) find that far too invasive and seek iron-clad control over the data they receive.

    Unfortunately, I don't think this is the likely scenario. Probably most device manufacturers will provide a preference which permits you to turn off "unsolicited advertising" delivered via a certain protocol, but other delivery methods (http, pop3, etc.) will remain just as viable. Too bad.

    Steve
  • by BWJones ( 18351 ) on Monday December 02, 2002 @04:37PM (#4796126) Homepage Journal
    Boy, what do you think the odds are of a U.S. sponsored project like this that will dump all of the data into our new government database?

    It gives new meaning to "Where Do You Want To Go Today", and sounds like a marketing/GOP wet dream.

    • It'd be more of "Where You Went Today", since the government would have it all recorded.
    • As a follow up to my previous post, I suppose there could be some good reasons for wanting this sort of data such as disaster planning, urban planning, resource management, service availability etc... However, this sort of data would be just what companies would want to target ads and its availability should be severely limited for obvious reasons of privacy. What worries me though is that cities and other organizations with this sort of data would realize they are sitting on a goldmine that could be sold off to the highest corporate bidder.

    • It gives new meaning to "Where Do You Want To Go Today"

      Apple switch story: And my PDA was all like 'Beep, Where the hell do you think *you're* going?'
    • I know! Just think of what PURE EVIL the goverment could do with a database filled with coordinates of where people travel the most. The horror! ::shudder::

      ummm oh nevermind.
    • This reminds me a bit of Platonic Chain [cdn-japan.com] where one of the girls tracks a guy she bumped into through the nationwide survalance network and figures out his favorite walkways; then hangs around the walkway to try to bump into him again and start up a relationship. It's creepy in a cute sort of way.
  • What is it about this that excites people? I am in no way one of those freaky-conspiracy-paranoid people, but this freaks me out.
    "This map does not register streets or blocks of houses"
    Sure, it doesn't register streets, but the data is there. Which smoke house did YOU spend the afternoon in?
  • GPSr fun (Score:5, Interesting)

    by faeryman ( 191366 ) on Monday December 02, 2002 @04:38PM (#4796135) Homepage
    I was sitting around yesterday thinking about what else can be done with GPS besides geocaching, etc. This is pretty cool.

    If you like this, you might like GPS drawing [gpsdrawing.com] too.
  • Drunk (Score:2, Funny)

    by Anonymous Coward
    Give it to me after a night of drinking. I'll make you one hell of a map!
    • it would probably make a more interesting map if given out before the night of drinking. i'm not sure i would want to see my own map though, nor hear the stories that go with each twist/turn.
  • Excellent! (Score:5, Interesting)

    by Marxist Commentary ( 461279 ) on Monday December 02, 2002 @04:39PM (#4796150) Homepage
    I've been using a Garmin GPS II+ that I originally bought for mapping backcountry nonmotorized trails, using a mountain bike. It was great for that, including its ability to upload its waypoints and track log to my PC, where I could integrate the data into mapmaking (GIS) software.

    On the water, I found its articulated antenna and lack of waterproofing a liability. I used it in a housing (heavy-duty ziploc type), but found
    it awkward. I just got a new Garmin eTrex, a 12-channel waterproof (1m for 30 min) unit that has the features I want. No internal maps, but I've never seen a handheld GPS that can compete with
    the big-screen units in that department-- they're as good as an actual NOS chart.

    If it were possible to do so, I would love to donate my map data to such a project - perhaps an open source map project? It could make for some exciting orienteering!
    • Re:Excellent! (Score:3, Interesting)

      by flippet ( 582344 )
      That would certainly be useful for those times when you're hopelessly lost, find yourself and spend ages wondering exactly where you went.

      I spent two hours last month hacking round in a forest after going off the track while cycling; I'd _love_ to know where I went, and how close to various paths I must have gone...

      Phil, just me

    • I think it's an excellent idea to create some sort of structured repository for geophysical data. To draw an analogy, I love Google, but it worries me that Google owns their (increasingly universal) dataset as a private for-profit corporation. Map data about the globe is just about the most 'open' sort of information that a human could need... getting from here to there, and information about here or there, being pretty fundamental to life. There are all sorts of applications -- travel, leisure, commerce, play, whatever.

      The OSS community does a great job thinking about the pros and cons of open source *software* but doesn't do nearly so much work on the subject of open *data* with which to use the software. This issue is implicit in Slashdot favorites such as FOIA requests to reign in government, public domain vs. copyright issues, fair use, etc., but no one seems to formally frame the 'Open Data' issue in a way that motivates the same sort of response as does Open Source. We should start a new movement, parallel and complementary to OSS! Any takers? We need bandwidth and storage, just like everyone else... I see from Internic that mapdata.org is available. Someone want to hack out a good MySQL table structure to hold it all? Lemme know when we open the project on SourceForge... etc.

      Be active!
  • hey... (Score:4, Funny)

    by Niles_Stonne ( 105949 ) on Monday December 02, 2002 @04:42PM (#4796174) Homepage
    Hey, what's that one that keeps wandering around that street corner...
  • by sssmashy ( 612587 ) on Monday December 02, 2002 @04:42PM (#4796178)
    Finally, a way to track the "real people" movements of residents of Amsterdam. Now I can find the marijuana cafes and red-light clubs frequented by Dutchmen who know what they're doing, as opposed to settling for the crappy spots they push on tourists.
    • Unfortunately it seems the red zones that appear on the map [waag.org] aren't color coded to represent that. Also aparently absent from the color scheme are green spots to identify the hash bars.

      If they could get a representative sample of the population, this would be a great technology for city planners. What I would like to see are maps that instead of giving a week at a time - give cumulative maps for each half hour during weekday mornings and afternoons to identify which traffic routes to take or avoid.

      Given enough devices with a real-time hookup and it would be invaluable in directing traffic around problem spots. The same could be done in the NorthEastern US by putting ez-Pass readers into all highway onramps and offramps that didn't charge a toll but tracked traffic flow. Of course this could also have serious privacy implications as well.

    • HEADLINE: Amsterdam's sex industry soon to be no more.

      In a new survey studying the routes and streets used by Amsterdam inhabitants conducted over two months by the "waag society" a startling result is to be found: Less than five people are using the streets of the infamous "red light district". Following that discovery to its conclusion it is logical to predict the demise of the Amsterdam sex industry. Following the spread of this news, all the small entrepreneurs and owners of SME in the disctrict have formed an union to promote their wares and plan to combine forces to present the buyers with new incentives and and discounts like "buy one, get one free".

      On the other hand, religious leaders around the world have rejoiced at the high moral Amsterdam inhabitants have chosen to follow despite the temptation, with the exception of his Holiness the Pope John Paul II who was heard muttering under his breath "damn, where will I go for my cardiovascular exercise now?" while the founder of the Church of Satan, Mr Anton Szandor LaVey, was found on the site of the tragedy where he issued a communique in which he deplored the current situation in Amsterdam and encouraged Amsterdams denizens of all sex to provide for the needy that may be left after the demise of this glorious industry by "taking a whore in your home and in your bed", and, "for the more evil of us blessed by your Dark Lord with pots of cash, to provide for the young, it is never too early to start a good education". He also encouraged those that do not have enough money to do so to "provide to the needs of the poor sod^H^H^Hconsumers who will suffer from the destruction of such a wonderful industry".

      Ok, it didn't come ot as funny as I hoped but its 22:00 and my funny bone is already asleep, so bugger.
  • by Tony.Tang ( 164961 ) <slashdot&sleek,hn,org> on Monday December 02, 2002 @04:43PM (#4796193) Homepage Journal
    The images are absolutely fantastic, and go to demonstrate just how small our lives are. Cumulatively, all their users contribute to a very revealing map of Amsterdam; however, individually, most stay in a very small subset of the area. It's easy to see how those east-side/west-side stereotypes can develop given that most people really only live on one side and never really go to "the other side."

    The visualization technique that they use is really cool too -- it lets you see more vividly the areas that get traversed (cumulatively) more heavily.

  • This is what I want todo myself with my etrex, mapping motorcycle trails (as tracks), and having a website to share them ... Never thought of putting them on random people and telling them just to go wherever ;)
  • uh, hello? (Score:2, Funny)

    by tps12 ( 105590 )
    Government tracking with satellites == bad, remember?

    I swear, when they finally start installing video cameras in everyone's houses, all they'll have to do is say they're BlueTooth enabled or XML-RPC enhanced and the geeks will eat it up.
    • Re:uh, hello? (Score:3, Insightful)

      by LostCluster ( 625375 )
      Government tracking == bad, private group tracking data for limited purposes == good.

      Tracking me to give me a speeding ticket every time my car's speed > 66 mph == bad... tracking me so that the world can know trafic's moving at 75 mph on route 3 good.
    • Re:uh, hello? (Score:2, Informative)

      by faeryman ( 191366 )
      I know this is halfjoking, but ...GPS units like the ones used in this example do not transmit your position, only triangulate it and store it locally. Someone has to download all the routes off of it to track you.

      Some systems (like the vehicle locator systems) use a satellite uplink though to transmit the position given off by the GPS though. This is totally different than Big Brother stalking you just because you bought an eTrex :) But it is possible for it to happen given the proper combos of technology.

    • when I first got my GPS, I tried this for a week. I got bored when all it showed was route from the coffee pot to my cube to the bathroom and back.
    • by nebenfun ( 530284 ) on Monday December 02, 2002 @05:06PM (#4796353)
      Government Agent: How would you like a free child safety camera?

      Average Geek: Screw you! You agent of MS...

      Government Agent: What if I said that it ran linux?

      Average Geek: Screw you...hmmm, did you say linux?

      Government Agent: Yes, I did.

      Average Geek: Does it support...

      Government Agent: Ogg Vorbis? Yes, of course.

      Average Geek: I'll take five.

      Government Agent: Going to run a Beowulf, eh? Hehe...you crazy geeks.
      • Free? Cool!

        I'll hack it so it does nothing except scan the digits of Pi to find the longest consecutive string of 4's.

        -
  • Seriously. I've got a GPS, and a link cable for my PC. I want to make a map of my life travels :-)

    -S
    • by faeryman ( 191366 )
      It's not too hard! I'm interested in this sort of thing too.

      You'll need some software to gather your paths from the GPS, and some digital maps to overlay them on.

      Some of the popular software is EasyGPS for the PC, and GPSy [gpsy.com] and MacGPS [macgpspro.com] Pro for the Mac. You can download a free version of each.

      The maps are a little harder to come by though. Here is a list to get you started. [gpsy.com] Some are free, some cost up to about $100 depending on size, scale, and detail. You can scan in your paper maps and calibrate them in some software too.

      I think this is really cool - I'd like to have a map of North America and see where all I've been :)
    • I want to make a map of my life travels :-)

      Possible uses for tracking your life adventures:

      • CIA knows where to point the orbiting laser if you need to be assassinated.
      • You have a built in alibi if you ever get accused of being somewhere you're not. (would require secure storage, including from you)
      • Stalker is able to view where you are and decides to drop in.
      • You might be well off, so muggers can see your routine, and wait till you're in the bad part of town.
      • You have built-in lo-jack in case you're kidnapped.
      • You can look at your "location log" to see where you made that wrong turn.
      • You can see pretty curves and loops from the night you attempted to walk home drunk.
      • Letting your children or future historians have a better idea of what your life was like.
    • I did this! Got my GPS and some software to make a perfect map of me sitting on my duff at the keyboard, with a few lines indicating the occasional bathroom break and trips to the supermarket.
  • Red Light (Score:2, Insightful)

    by kiley ( 95428 )
    It is great to see that every one of those people spent some time in the Red Light District. :)
  • Now they need a distributed cluster of web servers to fight the /. effect. Can anyone mirror some of the better images from the site (if you can get them) so others of us can see them?
  • The GPS server will only record a whole bunch of coordinates oscillating up and down, up and down...
  • Who do you trust? (Score:4, Insightful)

    by LostCluster ( 625375 ) on Monday December 02, 2002 @04:53PM (#4796265)
    One use I can think of this would be a data source for traffic reports. If the sensor is moving quickly, it's safe to assume that whereever that sensor is, there's a highway operating perfectly fine. If a sensor comes to a stop or goes slower than normal speed on a highway (excluding tollbooths and rest stations, zones that I'm sure will be quickly identified) that indicates that something has gone wrong such as an accident or blockage. Whatever it is doesn't matter, so much as the fact cars aren't going at the proper speed. What would result from this data is a hot-cold map of the highways that indicates pixel by pixel where the road is at full speed, and where it's not. The only thing is, I'd much rather that sensor in my car be reporting to a private traffic-reporting company than the government....
    • I forget the name, but there's at least one startup in the Bay Area proposing to do exactly this, but with cell phones. I think they are proposing to use the new GPS functionality required for emergency (911) calls.
    • Re:Who do you trust? (Score:3, Informative)

      by nairnr ( 314138 )
      If you want to see something of interest that does this check out Houston Live Traffic [tamu.edu] They use toll-booth transponders with sensors every 1-5 miles. This then gives them a live map of average traffic flow. They also have web cams at various spots.
      Overall this is an excellent demonstration of this kind of technology.
    • TrafficDodger [trafficdodger.com] uses existing highway sensors and fancy AI search techniques to suggest fast routes in traffic for the LA area. Free, at least for now.

  • Why not me? (Score:4, Funny)

    by r_j_prahad ( 309298 ) <r_j_prahad AT hotmail DOT com> on Monday December 02, 2002 @04:54PM (#4796266)
    They should have asked me to participate, they could be having a most excellent map of the red light district by now!

    Oh, it wasn't funded? Never mind.
  • by nlinecomputers ( 602059 ) on Monday December 02, 2002 @04:54PM (#4796272)
    ...cat. Just where the hell DOES he go when he vanishes for 3 days? Now If I can just tap into those orbiting "Star Wars" laser guns I could teach him to stay at home.

    Bad KITTY!!! ***death ray come down from the sky***ZAP! Fried cat found 2 miles away.

    Well maybe not...

    • It's a little known fact that the average moggy enjoys the intellectual pursuit of Cat Chess almost as much as sporadic violent confrontations with other random cats.

      The rules (based upon observation) are pretty straight forward, and are as follow:

      A point is scored by a cat that can simultaneously observe at least 2 other cats.

      Any cat observed by 2 other cats simultaneously is out of the game.

      That's it - so strategy plays a big part - on the one hand, a high vantage point lends itself to high scoring rounds, but has the increased danger of being spotted by other cats. These games can go on for days though, often ending only in a mass fight or when the competitors fancy some milk and maybe the chance to bat a small bird around for fun.
  • So, this way everyone would know that I skipped work on Friday, and spent it at the stip bar!

  • I wish I my city would use info like this for street planning. It would beat the heck out of those rubber lines counting axles by intersections.
  • by unfortunateson ( 527551 ) on Monday December 02, 2002 @05:03PM (#4796328) Journal
    ... you'd get a most excellent map of where the public restrooms are. Always useful when traveling to a foreign city.
  • This sort of thing has been achieved by ham radio operators for 10+ years now. In the ham radio community it is called APRS (Automatic Position Relay system). For more info check out http://web.usna.navy.mil/~bruninga/aprs.html
  • Over time this would develop better maps of surface streets and access. Some of the current maps of this scale would get you lost with non existent and mislocated streets. This could be used as a quality control for city maps. I would participate if given an opportunity
  • I have to admit, as interesting as a concept as this is, just how much detail does the tracker obtain? Is it only the geographic position? (yes I realize that that is what it is named after...) How will this play in regards to the "Big Brother" theory? Though it would be a great idea for use in the parole system, how long will it take for it to go beyond acceptable boundaries? Numerous people wish they could be the stars the see on TV, at the rate this technology could go, we could very well find our lives being that much closer to those some admire. Exposed, and never again to be completely and privately our own.
  • http://www.waag.org/realtime/images/kaarten/2-11-4 0d.jpg [waag.org]

    those bright red blotches must be the smoke shops and red light district. high traffic!
  • the amount of traffic in one section of town was mapped to a highway calculated to be 50 lanes wide, but upon further investigation turned out to be where the greatest number of brothels reside.
  • i definately suggest a visit.

    but seriously folks. that city is old, circular and downright confusing to find your way around. and that's when you're sober, after a couple of good coffee shop visits, forget it. everything looks the same (the locals should attest to this), and the city is a big horse shoe. so if you take one wrong turn you wind up who knows where!

    hell. one night i spent 2 hours freezin my butt off, during the summer, at 3 am until i could find a decent sign.

    i for one am glad to see gps put to a fun use.

  • I considered doing that a few years ago. Actually, I wanted to use inertial sensors to track relative position with good acuracy and then use GPS to nail down some absolute positions. Someone sitting with a laptop could click on icons indicating road type in real time too. I just wanted to make a videogame with I-696 in Detroit, so I could go over the standard 80-90 MPH.

    Paul

  • One thing I have noticed about a lot of open source stuff is that they all use those horrific Tiger maps. Tiger maps suck. Big time. They are good for just looking at street names, but when you want to use them for anything more than that they are not good at all. For example, the street I live on shows up on the tiger maps as being about 50 feet south of where it really is, and the intersection closest to my house is more than 150 feet off.

    But, because tiger maps are free, that is what is used. However, if you want to build your own talking GPS navigation system, using those maps is a bad thing - the routes would be all goofed up.

    So, I have been considering doing something like these guys so there could be some way to get decent maps out there for free that will give better results.

    However, I see a number of potential problems. First, you can't just turn on a GPS and start recording data. My Magellan 315 starts averaging when you sit still. Get under an obstruction and the data it records is all over the place. After only an hour of sitting you would have somewhere around 100 data points that don't exist. That would be a lot of work for someone to clean up.

    The other problem I see is really related to participation. It's one thing if you are in a small town with 50 or so streets in it - you would probably be more apt to get your town fully mapped. However, living in the Big City, I only really travel a few streets during a typical month - mainly highways and interstates, with the occassional side street. Since the ways I travel always have a ton of traffic on them, that means most everyone else goes that way too - probably including a good number of people who might be participating in such a project as well.
    • So ignore the data points which are close together during a long period. You're not particularly interested in data from an hour when you're not moving. Throw away data from periods when you're not moving or when it has been "too long" since a GPS reading.

      If the data is coming from a bunch of people who are wandering around for weeks, they'll probably run through the same area several times and generate several valid data points. Even more if they keep doing it for months.

      Matching the raw data to actual locations is a different problem. Let's say we start with TIGER maps. Use speeds to locate and confirm the highway locations. People who enter/exit a freeway will show where the limited number of access points are, so now the location of those intersecting streets is known (if TIGER doesn't show the ramps, you might have to record them -- easy to do that if you care). Cars which use those known streets allow correlation of TIGER locations of those streets. Turns and cross traffic show intersecting streets -- counting number of blocks from highways allows confirmation of location of all individual streets (alleys would add some confusion). Streets with curves in them allow further confirmation of locations along the street. Patterns of traffic pauses show STOP signs or traffic lights. Areas with only interpolated data hint at tree cover or tall buildings.

    • One thing I have noticed about a lot of open source stuff is that they all use those horrific Tiger maps. Tiger maps suck. ... and the intersection closest to my house is more than 150 feet off.


      That's one of the cans of worms I have been pondering deeply ever since I demo-ed a PostGIS based system that lets random users lodge spatial data.How on earth do you do meaningful QA on that quantity of data? Especially when many people are happy to use layers such as TIGER.


      FWIW, I think that collecting raw GPS tracks is a low value activity. I think the most value will come from validated overlays put together in a Wiki fashion. Leave it to the Cave Clanners to maintain a Wiki style layer of drains and urban tunnels, leave it to the geeks to maintain a WiFi layer. Pull you favorite overlay sites together in your PDA and enjoy an augmented reality...


      Xix.

  • A surprising result: 90% of the people seem to either stay in one place, make a trip to the convenience store, or take a bi-weekly trip to this one hippie looking guy's front porch. The map basically looks like this:

    \
    /
    \
    -=-=-=-=-=* :)
  • by jki ( 624756 ) on Monday December 02, 2002 @05:35PM (#4796570) Homepage
    ...this story reminds me of one the dark-hour ideas. Would not be sometimes handy if you could "rent the eyes" of people around the world, for say 5 minutes. Just like in the GPS'ing Amsterdarm scenario, there would be people in multiple cities with world - carrying GPS and a digital (video) camera.

    Then, when you spot someone in a interesting place, you could get control of his camera for some time. Maybe there could be the option donate the guy $5 and ask him to move 100 feet left.... now that's a real big brother scenario :) Anyway, it could be fun too, to be "in the place" when something interesting happens...talking about Amsterdam...(red) lights, camera, action :)

  • Whenever I'm gettting to know a girl I'm intrested in this sort of image always comes to mind. I always wonder "could we have crossed paths before?"

    Over time the lines might come close to crossing, but they never touch. Then one day it happens.

  • I can just see it now, Your spouse looks up your GPS data and finds that just about every night you said you were 'working late', you have thes long traces at their best friend's house

    (Sorry: Former best friend).

  • The city of Amsterdam has extensive canals and waterways. If people wearing these transmitters use any canal boats for transportation it seems as though the maps generated would incorrectly identify roads that "don't exist" and would lead people into the water!
  • Home -> BART station -> (trip on BART..) -> Embarcadero (SF) BART Station -> Java City -> Caltrain -> Work.

    Reverse to get home.

    Toss in Home -> Fry's -> Home on the weekend.

    Some people just shouldn't map out their lives. heh.
  • Funny, nobody told me that Amsterdam is a sovereign country! Or maybe they meant residents of Amsterdam?
  • The site includes aggregate maps, and those created by individuals, including a subway driver,

    I'll admit I can't view the site because of the /. effect, but Amsterdam has a subway? I sure missed seeing that while I was there. Doesn't seem like a likely thing for a city reclaimed from the ocean to have, and less likely for a GPS receiver to be able to track a subway driver.

  • subterrestrial GPS? (Score:2, Interesting)

    by flowerp ( 512865 )

    So how exactly does a subway driver get a GPS
    signal on the job?

    And how do Australians get GPS? They're 6000 miles
    below our feet!
  • I can see that this is a great way to get the actual paths and roads into a database to be used for mapping and so forth, but how do we complete this mapping solution with a way to label those paths and roads?
  • I did this last year (Score:2, Interesting)

    by jjeffers ( 127519 )
    I did something like this last year using amateur radio's Automatic Packet Reporting system. Basically there are thousands of amateur radio operators that broadcast their GPS position. Using software I wrote along with MySQL [mysql.com] and Mapserver [umn.edu] I was able to create maps that showed real-life traffic flow.

    You can see a sample of this type of map and learn a little bit about it at http://aprsworld.net/info/paper2002/giant-map-of-l a.php [aprsworld.net]

    -James Jefferson
    KB0THN

    Find me [aprsworld.net]

  • GPS over GPRS (Score:3, Insightful)

    by ukryule ( 186826 ) <slashdot@yule . o rg> on Tuesday December 03, 2002 @12:03AM (#4798930) Homepage
    One of the neat things I haven't seen comments on was the fact they were using GPRS to transmit the GPS data in real-time [waag.org] - so the GPS data really was uploaded as it was generated. This is the sort of thing that GPRS is really good for - it's low bandwidth (so doesn't cost an arm and a leg) and constantly updated.

Math is like love -- a simple idea but it can get complicated. -- R. Drabek

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