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Open US GPS Data?
tobiasly writes "I read an article today about a map error on the popular Garmin GPS devices which often leads to truckers in a particular town becoming trapped. From my own experience, every electronic map I've ever seen (Google, Mapquest, my Mio GPS) has the layout of my neighborhood completely and frustratingly wrong. A quick search turned up only one open-source mapping project, but it's for New Zealand only. Why are there no comparable projects in the U.S. or elsewhere? Obviously such a project would need a good peer-review/moderation/trust system but I'd gladly put in the time necessary to drive around town with my GPS in "tracking" mode, then upload, tag, and verify my local data. Has anyone with more technical knowledge in maps and auto-routing looked more into this? Are there technical limitations to such a project? Should the government subsidize a project to create open, free, up-to-date electronic maps? Surely there is a public benefit available from such a project."
It can definitely be frustrating. There's a street near my house where I grew up that is complete on every online map I've ever seen, but the truth is it's actually two dead ends that don't meet up. I've seen other mistakes as well. Unfortunately the same bad data keeps getting recycled everywhere, because companies are too lazy to verify things. I'm all for an open source mapping project, or at the very least better ways of reporting errors.
-mrxak
Onions Will Kill You
Open Street Map is a good start but needs some enhancements to allow for proper data attribution and segregation of the different feature types (point, line, polygon) into "layers". Being able to distinguish a bike path from a highway is significant. A community based approach to data reviews would also be nice (i.e. if a user always enters bad data, other users could moderate them so that their input doesn't have the same "value" that a good contributor does).
I had an experience recently where I was driving through an unfamiliar town the next state over, following my Garmin. It took me on a route that, while leading eventually to the right place, did not seem to make much sense given the other roads available. I noticed a camper in the lane next to me that didn't seem to belong, and that driver also had a GPS navigator mounted on his windshield. So I found myself wondering: does he have the same unit (or data source) as me? If I did a study of all the non-local cars driving down this road, how many of them would have the same unit in their cars?
There are several interesting implications, the most obvious being "sponsored routing" down a particular street in a business dist.....gotta go, I'm on the phone with my patent attorney.
Evil is the money of root.
http://www.census.gov/geo/www/tiger/
Format is a bit obscure, but it works rather ok. We were able to use the data to draw road maps and then find paths on them. I'm sure it has it's own problems too but maybe you could contact them and point out the errors.
There exists some positive integer N that you are the Nth person to read this signature.
You can submit map errors and recent road changes through Navteq's Map Reporter site (http://mapreporter.navteq.com/).
Check out Roadster:
http://cairographics.org/roadster/
Here's a screenshot:
http://www.mp3car.com/vbulletin/attachments/linux/34562d1157775234-linux-gps-roadster-roadster-0.2.4-1.png
It has data available for the united states, download, compile, and give it a shot.
I've reported errors to several map makers, including Google maps and the makers of the maps in our phone directory. They all have ways to report errors. If each one of grabs a map right now and reports just one error, just think how much better the maps will be next year...
What a fool believes, he sees, no wise man has the power to reason away.
I am TheRaven on Soylent News
Roadnav is a fairly good open source turn-by-turn nav solution that uses TIGER data. Check it out: http://roadnav.sourceforge.net/
If you wait for a manufacturer to make all the corrections, you will wait forever because they can't check all places at all times and certainly wouldn't know all the best PoI and restaurants even if they're full time residents. For instance, both TomTom and Garmin GPS list a TGI Fridays that was a few blocks from my home as still in business when, in fact, it moved 2 miles away over 6 months ago and is being replaced by a new restaurant. There is also a fantastic Thai restaurant (it has won awards for best Thai) tucked behind a strip mall that isn't listed and I'd love to add it.
Personally, I like features like this on TomTom, but yes, an open source database would rock. Even something that pulled from google maps would be cool, IMO, as long as google maps stays free.
Polls in the OSM community have shown that a dedicated mapper can exhaustively map an area of 40k inhabitants in urban areas, and about a quarter of that inm more rural areas, while the occasional mapper can still easily cover an area of tens to several hundred inhabitants. The only drawback is (in opposition to wikipedia for example) that you have to be physically at the location to do a current and comprehensive map, so you can't do something like "we only need 200k mappers to get the world done".
Folks, be aware that one way that a mapmaker "improves" on a copyright protection is to intentionally alter a small section of a map (and in a book, a few at random) that is hopefully not used. This helps them to prosecute somebody that steals the map information and resells it. Granted, this is known for hard-copy maps, but I believe it is also true for GPS maps as well (call them the "soft-copy" versions).
I can attest to this because near where my parents live on most maps there is a road that appears to go from their development right into the next one. Unfortunately, there is a gap of about 100 feet where there is no road but rather a swampy stream. And it gets better... When they were laying sewer lines, they put in in this swampy stream so that if somebody wants to extend the road they will have to build a bridge over the stream. So this would involve (and has involved) the state, county, and sewer authority determining how much each should pay.
You can guess how far this has gotten...I'm expecting it may happen when my (as yet unborn) great grandchildren reach 21 years of age...
Of course, this was the source of a lot of fun during the summer when growing up...my brother and I would sit out on the front lawn in the twilight/evening/night and watch the cars come zooming down to take the "short-cut" and then have to slam on their brakes and then back up and wander around aimlessly. Nobody ever crashed into the swamp, but one person almost hit the barrier at the end of the street.
Yes, I did call the map people (ADC) and report it several times over a decade. It's still that way in the latest edition, and I've seen the same mistake in an in-dash GPS display for the location in one car.
Guess it's now "Driver Beware"...
Supreme Granter of Doctor of Obviology Letters ("A FIRM Command of the Obvious")
In France I was lead down a country lane that got narrower and narrower and eventually I came to the conclusion that I would not get my standard car through, so I turned round. Now My wife has a terrible sense of direction - or to be fair she is American and navigates by intersections, junctions and so on rather than by landmarks like you have to with the squiggly roads in Europe. (Actually I am as bad in the USA, all the roads and junctions look the same to me and by the time I read an exit sign's road number I have passed it) As I headed back the way I came my GPS was still locked on to the old route and said "make a U-turn when its safe to do so". It did this a couple of times at about 5 minute intervals when my wife said "you could have turned in the gateway there". I pointed out that it wanted to send us back the way we came, and that we had given up on that route. My wife said "I don't know why you brought that thing if you don't even listen to it". This got my teenage daughter and I laughing. Big mistake. Most women dislike being laughed at by husbands and by teenage daughters. Both laughing together is even less popular. My wife is a Texan, and Texan women don't usually keep it to themselves when they are unhappy.... End result, my GPS is at maximum throwing distance in some field in France.
Try searching Google maps for "Dummy1456".
Well, map makers don't really make maps anymore. They collect data like that which is available at tiger maps (if it is still around) but they get this data from cities, state, county and federal courthouses. The cities and political entities makes the maps and basically just sell the information to the map makers who organize it and compile it to the same scale and fit it to their presentation.
Often the errors you see is because there was a planned development that never went through it they (the city/county whoever) changed the traffic flow more recently then the map data is. I found this to be the case back in 1991 when I was delivering pizzas. I grabbed a city map from a tourist booth only to find some roads didn't exist. I purchased a random McNally or whatever the name is from a gas station to find the same errors. After I went to the city engineers office looking for an accurate map, they explained this to me. It was also interesting that I would watch development projects going up and already have a map complete with street names several years after this.
If you see a map problem with any map, I would bet it is something to do with the political entity more then the map maker. It might be them in some cases but roads dead ending when they should go through a town is the cities fault. And you will likely find the same error across multiple maps.
Works fine on my GPS - see for example http://www.gravitystorm.co.uk/shine/archives/2007/01/07/osm-on-my-gps/ or even a customised OpenStreetMap based garmin map at http://www.gravitystorm.co.uk/shine/archives/2008/01/13/osm-cycle-map-on-my-gps/ for cyclists.
That's the difference between OpenStreetMap and many other open-source GPS projects - we can make real maps for the GPS devices instead of just collections of GPX waypoints. And seeing as all the data is available for customisation, we can do cool things like the cycle maps instead of just general (road-user orientated) ones.
"the one thing you need in a map is accurate data you can rely on"
Fair point, but I wonder if you realise how many mistakes there are in commercial maps. OpenStreetMap is already more useful, right now, for (say) navigating along many of the Sustrans cycle routes in Britain than any printed map is. I have it loaded onto my handheld Garmin GPS and it's saved me from getting lost several times.
OpenStreetMap has also shown that, where there's a critical mass of mappers, it gets updates faster than the commercial maps. There's a lot of UK housing estates that you'll find on OSM but not on Google Maps.
Apparently you don't understand the concept of cuisine so I'll try to enlighten you. There is very little quality difference between a reasonably priced and expensive restaurans. By and large the food is pretty decent but you'll end up with mediocre food in restaurants with a Michelin star just as often as you will end up with stellar food in a more mundane place. The difference, my friend is exclusivity. There is some part in our brain (I believe it's called the Nucleus Superfluous) that makes regular stimuli more enjoyable when you have been waiting for very long. This is exactly why so many people went to see Episode One, while there was very little reason to assume it was going to be good even before it was reviewed.
The same principle holds true for restaurants. The first couple of bucks will go into food quality and better service. There is a very real difference between a $5 hamburger meal and a $15 steak. But the next $50 will go into square plates, french accents and, of course, exclusivity in the form of missed opportunity costs. You pay for the fact that they might have sold the food to the person currently waiting at the bar.
In this light you'll probably understand how downright stupid it is to share that little known Thai restaurant behind the strip mall with the rest of the planet. Before you know it, hordes of TomTom-toting patrons will crowd your once lovely restaurant. Prices will skyrocket, portions will shrink and before you know it it will obtain a Michelin star and you will have to find somewhere else to eat.
Having mapped a couple of square miles for OpenStreetMap, I can attest to the fact that these alterations are incredibly common on Google Maps. There are half a dozen within half a mile of my house, most being added curves or extensions to dead-end roads and added or removed traffic islands. Google also cunningly add fake roads to the map data which correlate with features which look like roads on the satellite imagery but actually aren't - they're private drives, streams, paths rather than roads through woodland etc. The ones near me wouldn't seriously affect navigation, but some I've seen in the past would. Oh yes, Google Maps is also shifted by about 5m from WGS84 (GPS coordinates) round here, I presume this is intentional too.
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