Announcement

Collapse
No announcement yet.

OT: Treachery of GPS Devices.

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • J Tiers
    replied
    Originally posted by danlb View Post
    Google appears to have done an impressive job of mapping addresses to the physical location. When I go to street view for an address it almost always shows the correct spot.
    I've noticed a number of instances where the spot indicated by Google is not even on the correct side of the street.... and may be significantly wrong in location.

    The "street view" can correct that in some cases, if you can see the actual location. In other cases, it's more difficult. But it is quite nice to see the building in "street view", that gives important visual cues to help locate it while you are driving.

    Street maps in cities need no compass. As soon as you find the second intersection , you are fully oriented. In other places, there are usually many clues to identify "north", ranging from where the sun is (or some other star, at night) to where the lichen is on the tree, etc, etc.

    As for the combined usage, it is more about being able to look at the screen at the same time you talk and listen. OK in some cases in quieter areas, where you can hold it out in front of you, but less so outdoors with a wind, or traffic noises.
    Last edited by J Tiers; 01-05-2014, 12:58 AM.

    Leave a comment:


  • danlb
    replied
    Originally posted by J Tiers View Post
    The GPS receiver knows where it is. The problem is with the translation of that to a location with respect to roads and structures. Someone has to cross-link it to a map, and that is where the trouble starts.

    Coverage in the hot coastal areas is good, although I guess tall buildings mess it up a bit, but out in the sticks (flyover land), it apparently isn't a high priority to get it right.... and I can see why.... it's expensive to KNOW you have it right....
    That's not really a problem. In the late 1960's my dad showed me how his firm was using surveys and 3D aerial photography to validate old maps so they would only re-survey as needed. Modern computing power has made it super simple compare aerial shots with the database to see if the road is where the map says it should be. Google appears to have done an impressive job of mapping addresses to the physical location. When I go to street view for an address it almost always shows the correct spot.

    Maps work fine, and don't need power.

    I believe you are right, phone apps will likely replace the dedicated GPS.... They can combine maps with the GPS receiver, adding accuracy and allowing some creative problem-solving. It makes a lot more sense to me, although I don't have a smart phone (I'd have one but they are too big to carry..... I have pockets, not a purse).

    The one benefit to a separate one is that you can call AND use the GPS receiver at once....
    In the last few years the 4G networks allow the GPS and phone to work at the same time.

    "Maps work fine, and don't need power." That assumes that you know where you are and have a compass and light. I can navigate quite well with paper and compass but I know many people who can't.

    I've suggested that my 80 year old mom and her boyfriend learn to use the GPS on his phone just enough to figure out their current location. Given that information they can use a map to find a route to home. They live in central Oregon where it's easy to get lost.

    Dan

    Leave a comment:


  • andywander
    replied
    Treachery is a willful betrayal, and I can't believe that GPS devices are actually programmed to do that.

    Sure they sometimes use incorrect info.

    But, sometimes, I hit my finger with the hammer when I am pounding in a nail. I don't consider that to be treachery, by either the hammer or myself.

    And it wouldn't make me go back to using rocks to pound nails, instead of those damned newfangled(and treacherous) hammers.

    Leave a comment:


  • Wheels17
    replied
    Sometimes the map "improvements" seem to be just the opposite. We've lived near an 11' 6" railroad bridge for 17 years. In the first fourteen years, I saw the bridge hit twice. In the last three years, I've seen it hit 7 times. Speculation on my part, but I'll be some gps map changed and now routes semi's down that road.

    Of course, there are at least 5 signs indicating an 11'6" bridge in the mile leading up to the bridge, and the stupid drivers keep running into the bridge. Including at least two 13 1/2' tall trailers. Those hit low enough that they clean the top completely off the trailer.

    Our bridge doesn't compare to this one, though: http://www.youtube.com/watch?feature...&v=xzkWTcDZFH0

    Leave a comment:


  • metalmagpie
    replied
    Originally posted by Stern View Post
    WOW, really confused on this thread ... started out as a "I hate GPS" and turned into "trucker bashing" ???
    I would have thought that it would be clear to anyone that I was completely kidding about directing trucks to a Bermuda Triangle. But for those who didn't catch that, and were offended, I apologize. I really don't have anything against trucks. I just like to poke fun sometimes. Like, for example, I tell people that I know exactly how to cure overcrowded freeways - it's simple. Just take the driver's licenses away from the women! It gets a snicker sometimes, and rarely offends because people know me and that I'm way wack irreverent. Nuff said. - metalmagpie

    Leave a comment:


  • J Tiers
    replied
    Originally posted by danlb View Post
    It sounds like you have had some bad experience with some very poor GPS software or GPS maps that were not updated regularly. That's a shame.
    Nope, I don't have one, the few ones I have worked with belonged to others, and I wasn't impressed with their performance (didja guess that?). The highway 40 thing was widespread enough it got into the local paper....

    The GPS receiver knows where it is. The problem is with the translation of that to a location with respect to roads and structures. Someone has to cross-link it to a map, and that is where the trouble starts.

    Coverage in the hot coastal areas is good, although I guess tall buildings mess it up a bit, but out in the sticks (flyover land), it apparently isn't a high priority to get it right.... and I can see why.... it's expensive to KNOW you have it right, and really, do you think those folks really CARE? In general they do not, actually, so it's a "whatever".

    Maps work fine, and don't need power.

    I believe you are right, phone apps will likely replace the dedicated GPS.... They can combine maps with the GPS receiver, adding accuracy and allowing some creative problem-solving. It makes a lot more sense to me, although I don't have a smart phone (I'd have one but they are too big to carry..... I have pockets, not a purse).

    The one benefit to a separate one is that you can call AND use the GPS receiver at once....

    Leave a comment:


  • danlb
    replied
    Originally posted by J Tiers View Post
    It likely is true that if you are in a largish city, especially one on the east coast, you can be pretty sure of the accuracy of the GPS when it comes to the location of upscale restaurants. Possibly also for other things, if they don't interfere.

    If you live elsewhere, not so much, but then, if you live elsewhere, you aren't important enough to need a GPS, or to be able to afford one, so it is of little moment if the maps are accurate or not.....

    This is almost surely an evil attitude.... but it may be reasonably true for all that.
    It sounds like you have had some bad experience with some very poor GPS software or GPS maps that were not updated regularly. That's a shame.

    I've been using consumer grade GPS units for 20+ years and have found them to be quite usable. When traveling through unfamiliar areas of the western US the information was as good as the current AAA guides. Coincidentally, my wife's Magellin GPS has the AAA guide information built into it.

    In recent years we've stopped using the dedicated GPS units and started using android phones with Google Maps and Google Navigation. It has the best, real time information on traffic problems. It also has a great interface for finding a specific restaurant or store as well as just finding the nearest one.

    Like all tools, you need to read the manual and learn to use the GPS to get the most out of it, and then you need to maintain it with frequent updates.

    Geocaching is a good game for practicing your GPS skills. http://www.geocaching.com/

    Dan

    Leave a comment:


  • EddyCurr
    replied
    With the margin of error demonstrated in my examples, in
    Europe where countries are smaller, the trucks could have
    been off the mark by an international border or two.

    Say what you all will, the problem still comes down to a
    user interface that takes your input, discovers it doesn't
    recognize this and unilaterally decides to direct to some
    other random destination without so much of a how do you
    do.

    Kind of like the old days when you could format your drive
    without the [Are you sure?] dialog requesting confirmation.

    .

    Leave a comment:


  • TRX
    replied
    The GPS was probably working just fine. The problem usually lies with the satellite navigation software, which is an entirely different system, even though people seem to call it "GPS", like the people who call a dish TV antenna a "satellite."

    Leave a comment:


  • The Artful Bodger
    replied
    Unfortunately, as has been discovered in fairly recent times, the earth is not flat! But maps are flat so there is always the potential for a street on one flat map not quite meeting up with the same street continued on an adjoining map sheet, of course very clever people have been trying to eliminate all these little glitches for some time now but there will be plenty more waiting to be found and until they are that will be just example of why a GPS device might lead you astray.

    Leave a comment:


  • J Tiers
    replied
    It likely is true that if you are in a largish city, especially one on the east coast, you can be pretty sure of the accuracy of the GPS when it comes to the location of upscale restaurants. Possibly also for other things, if they don't interfere.

    If you live elsewhere, not so much, but then, if you live elsewhere, you aren't important enough to need a GPS, or to be able to afford one, so it is of little moment if the maps are accurate or not.....

    This is almost surely an evil attitude.... but it may be reasonably true for all that.

    Leave a comment:


  • jlevie
    replied
    The "accuracy"of GPS navigation is primarily determined by the degree of detail in the "address to coordinate cross reference" that has been manually entered into the database. It isn't unusual to have the GPS announce that you have arrived at your destination when you are a block or more away. Even in areas that have existed, unchanged, for a hundred years. All that means is that the level of detail in the database is only as good as block numbers (or worse). The GPS knows that the address is in the block or some larger distance, but not exactly where it is because that it lacks that level of detail. As you move away from populated errors that distance can grow dramatically (to on the order of a mile or more in rural areas), depending on the importance of the "target" and area. And then, there can be gross errors in the database (it is a human activity). Add on to that changes in roads, etc., and it something of a wonder that GPS nav works as good as it does.

    I have a race car and have on occasion gone to little known (outside of the club racing community) tracks out in the middle of essentially nowhere. Plugging in the address of the track may not work as it may not be in the database. But the roads are in the database. So finding the coordinates via Google earth (the track is visible from orbit) and using that as the destination always works. On other occasions I've used driving directions to the location (for places not readily identifiable from orbit) and maps in conjunction with Google earth to find the coordinates for GPS navigation to the location.

    I really miss the way GPS automotive navigation systems worked in the past. Because of limited memory, they had a computer based map database and routing system that you used to load map data of areas of interest and optional routing data. Being able to see that level of detail and area on a computer monitor and seeing the calculated route was a pretty nice feature as compared to what you can see and do with the current nav units and their tiny screens. And none that I know of now have easy ways of designating a specific route.

    Leave a comment:


  • dp
    replied
    My point earlier was old maps are of little value to find your way today. GPS maps are notoriously not new because it costs to update them. There are also projection errors in the GPS maps owing to datum differences so the lat/log from the GPS doesn't fall exactly where the real world is on the map.

    If you depend on maps then get a map set and keep it current, be it dead tree or digital.

    The world changes daily, particularly regards road repairs, closures, and re-routing. Boston during the big dig is a good example. This place: http://www.lib.utexas.edu/maps/united_states.html keeps old maps so I don't have to though I do have a friend who collects old maps for the historical information. Records of Route 66 are sketchy so having the original maps helps.

    Finally - if a guy is just plain stupid the best maps won't help. Bottom line though is you can only blame the driver not the equipment.

    Leave a comment:


  • danlb
    replied
    I think that people are expecting more of portable GPS units and their software than is reasonable.

    The GPS mapping software does not have the physical location all the billions of street addresses in the world stored in it's little 256 megabyte memory. It has the range of street numbers for a particular stretch of road AS FILED BY THE DEVELOPER WITH THE CITY/COUNTY/STATE. If the road is one block long and has 20 addresses on it the GPS guesses that each house is 1/20 of a block apart. Extend that to country roads and you get 5 houses in 10 miles, so it guesses that the houses are 2 miles apart even though the actual house locations may be 100 feet apart.

    Now loop back to the bold text. The initial map of a new subdivision is provided by the developer to the authorities. If they don't file it properly or if they don't build exactly what they planned, the maps end up being off. Sub developed acreage may just show several hundred acres as one big parcel with a range of addresses. Those addresses end up assigned to the point where the property touches an established road.. That's hardly the fault of the GPS software. That appears to be what happened in the OP situation.

    I don't see where the paper maps are much better in maps are much better in EddyCurr's situation. The biggest advantage of the paper map is that it would not show the address of the brand new truck terminal at all. If it's not on the map the trucker would call for directions. The directions may or may not be viable, but that's a different problem.

    One of the things I like about using Google Navigation is that it will show me street views of the turns on the route as well as the destination.

    Leave a comment:


  • Stern
    replied
    WOW, really confused on this thread ... started out as a "I hate GPS" and turned into "trucker bashing" ??? I have a GPS and have no issues, because I dont expect miracles. Sometimes it screws up (or you screw up entering data) but I find it a lot easier than maps. I drive for a living doing service work, and my GPS cuts travel time and aggravation a lot. Its a tool, not a "mystery box with godly powers". Just use it as a tool and there should be no problems

    Leave a comment:

Working...
X