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GPS Slowly Changing How Things Are Done
Hemos forwarded me a link to a story at Fast Company about how GPS is changing the way people do business. Several good examples are used, from farmers in Alabama to anti-theft devices. Some notes on GPS' military origins as well. Also worth noting is how GPS, like computers, wasn't adopted overnight, but rather over time as applications were found.
"I'm working late tonight, don't wait up..."
..err, I meant to say, cool!
"Oh really? Then how come your cell phone is in Joe's Tavern with your secretary's pager bobbing over your coordinates?"
"...*dialtone*..."
.unsigged
I have a Garmin GPS V and LOVE it. The turn-by-turn routing has been a huge help. We started looking to buy a house and would print out a ton of MLS listings. Without the GPS we'd have to spend a lot of time planning our route. With the GPS we just punch in the address of the next house and off we go. Very accurate.
Maybe SCO can use GPS to locate *nix code in Linux. So far they sure don't seem to have found much of it otherwise.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
search ebay for the visor prism, - color palm handspring unit - $150 with shipping - used - 65000 colors
nice organizer with handspring expansion slot
--------------------
staples, etc. - handspring unit GPS magellan - 12 channel - $49 - new on clearance - software for moving map, location, speed, etc.
-------
this unit with good mapping software for $29 rivals dedicated color moving map GPS units costing thousands.
----
get the spint phone module from ebay for $20 for the visor handspring and now it is a phone too.
Comparable to DirectTV (see slashdot article about them). The signals would be scrambled unless you paid $9.99 per month for a "license fee". They could use the stupidest encryption around, and anybody who broke it would be put in jail and fined. Scramblin it for a military purpose makes sense, but scrambling it to protect "intellectual property" is just stupid. Unit cost for one more person to use it is zero. Like America's Army game, an example of good use of government to keep things sane. A libertarian might argue for donation-based entities, but either way it gets done.
-Libertarian secular transhumanist
We worked on a turn-key project over a year ago (before matters got screwed by an acquisition), and one aspect of the product was to track GPS position and record it every so often with a few other real-time parameters, such as speed, direction, and average MPH. The project completed the first product phase of deployment, but actually using the GPS data (while recording WAS working) was slated for phase 2. Unfortunately, I think the whole thing got mothballed because the company receiving the product was not technically inclined one bit. Such a waste of effort. It would have helped cut their yearly expenses down a lot.
As a long-time sailor, I have heard more stories than I can count about vessels lost or damaged because skippers entered bad coordinates for a buoy or harbor entrance. Are rogue tractors next?
"For the moment, they've managed to resist the hottest new GPS tool: tractors that steer themselves. The price is still too high, but the idea is appealing, because with an auto-steer tractor, they would be able to work at night."
without paying an outrageous monthly fee akin to protection money, or calling a company to do it for me for a fee, then gps will have arrived for me.
One stolen car, recovered by my family, not police.
One van, stolen twice, recovered by my family twice, not police.
One 4x4, stolen, never recovered, $10,000 loss, insurance settlement was a joke after months of haggling and threatening to sue.
My father and I use GPS receivers as often as possible. We are both Geocachers.
For those of you that don't know what Geocaching is, here is a quote from the geocaching.com FAQ:
"What is Geocaching?
Geocaching is an entertaining adventure game for gps users. Participating in a cache hunt is a good way to take advantage of the wonderful features and capability of a gps unit. The basic idea is to have individuals and organizations set up caches all over the world and share the locations of these caches on the internet. GPS users can then use the location coordinates to find the caches. Once found, a cache may provide the visitor with a wide variety of rewards. All the visitor is asked to do is if they get something they should try to leave something for the cache. "
Wardriving is a perfect example of how GPS has changed the way we look at computer security, especially where wireless LANs are concerned.
Check out wifimaps.com to see if your wlan has been scanned.
Can someone enlighten me as to why a farmer driving a tractor would need to know their location to a 1' accuracy?
The mind boggles. How many people are going to accept a system that lets their insurance company track everywhere they drive? Yes, I'm surely more obsessive about this kind of thing than Joe Average, but surely you don't have to be a privacy nut to have some issues with this.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
Not to shoot you down or anything but I work specifially with GPS. The GPS C/A code broadcast on L1 (1.57542 GHz) has never been encrypted. The military simply encoded ephemerides for the GPS satellites that were inprecise (this was called "Selective Ability") onto the L1 signal. This led to a user range error of ~30 meters. After this was turned off in 2001 the error went down to ~3 meters. There has always been the PPS ("Precise Positioning Service") P-code signal on the L2 frequency (1.22760 GHz). This is actually encrypted, and is what the military uses in its. Acurracy with this service can be in the range of centimeters (low dynamics case). Working with the L2 signal requires a security clearance and a bunch of goverment red-tape. In the next 10 years there is going to be an explosion of GPS tech. First off the EU is putting up Galileo, which will double the number of SV's orbiting the earth (more satellites in view = better positioning accuracy). Althought the signal structures are not the exact same, because they will be broadcasting at similar carrier frequencies designing a dual use receiver will be a piece of cake. Also GPS is being heavily upgraded. They are adding a third signal with M-code(L3), and adding C/A code on L2. There is also talk about increasing the signal strength, which is a great boon to indoor GPS and using the GPS signal for remote sensing applications. All in all it is a great industry to be in.
I would think most cellphones are (or at least will be) this way. GPS is something that is already there (due to the E911 thing), so why not make it available to the cellphone users so they can use it and you can claim it as a feature and say "our phone is better because theirs doesn't let you see where you are with our IntelliGPS HyperLocater technology." If it's not common now, I think it will be. I for one would prefer to buy a phone that would let me see the GPS data over one that wouldn't, all else being equal. Wouldn't you?
Comment forecast: Bits of genius surrounded by a sea of mediocrity.
which is a great boon to indoor GPS
Fantastic !! I will always be able to locate the TV remote no matter where it hides on me. Now wheres that fscking GPS receiver.....
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
Where do you work?
That's "GNU Public Slayings".
Look, if it hadn't been for France bailing your asses out 250 years ago, you'd have continued to have your "country" run by some unelected idiot called George whose only qualification to the job was that his father did it.
Thankfully the French were there to help you defeat King George III, and you avoided that situation.
NASA GSFC & Purdue University
What will ever happen to human progress if we start all being nice to each other?
Strange women lying in ponds distributing swords is no basis for a system of government.
I hate to sound pessimistic but since when is something this glaringly obvious considered "worth noting"?
Or maybe, given the topic, my pessimistic little note should be restated to ask how accurate would your GPS unit have to be to measure the size of the rock you'd have to be living under to not know that GPS wasn't adopted overnight?
Goodness. I'm starting to sound as biter as those people who post about the newsworthiness of new articles.
Like utility infrastructure. I work at a water company, and before a contractor burries pipeline, we use RTK (realtime kinematic) GPS to record its location down to 0.04' (or 1cm). So when line locators need to mark facilities its much more accurate. Normal GPS isnt that accurate, but we use base stations and radios to send correction data in real time out to the GPS collection devices.
The Doormat
If you're not outraged, then you're not paying attention.
Look, if it hadn't been for France bailing your asses out 250 years ago, you'd have continued to have your "country" run by some unelected idiot called George whose only qualification to the job was that his father did it.
Hmmm.... let's look at today
unelected? check
idiot? check
called George? check
his father did it? check
Looks like we need France's help once again. LIBERATE US, FRANCE!
FWIW, what cellphones use is generally not GPS, but good old fashioned triangulation. Which, interestingly, means it's probably more accurate than GPS too.
You are not alone. This is not normal. None of this is normal.
I swear when I first read this, I thought it said it would double the number of SUV's orbiting the earth. I started to picture a bunch of Expeditions slowly spinning around in space (with the drivers inside talking on cell phones of course).
Several good examples are used, from farmers in Alabama to anti-theft devices.
Up here in Canada, farmers have been using it to level their fields for years now. Canada is usually pretty quick to pick up new technologies.
The recount that was done had Gore win in eight of the ten scenarios, including the all important "If they counted every vote". The two where Bush won were the way the vote was counted, and the scenario where Gore got only the three counties he wanted recounted recounted.
This lead to certain newspapers putting up headlines of the "Gore would have lost anyway" variety. Which in turn has lead every freeper wingnut to claim that Gore lost the election even in the recounted version. BS.
"...because with an auto-steer tractor, they would be able to work at night."
Most tractors these days have headlights. Some of the larger tractors come with enough lights from the factory that it almost feels like daylight when they're all on.
You're not going to see a lot of GPS guided tractors any time soon. There are too many random factors to consider, like random patches of soft soil (mud or sand), animals (my grandfather accidentally ran a lame deer through a combine once... Ick.), debris in the field (rocks, tree limbs, etc), etc.
We'd need optical recognition systems to be good enough to steer around the junk you don't plan for using GPS. Also, some stuff you don't want to steer around, you want to remove it from your path.
GPS is useful with farming, though. Plotting soil samples, and then using that data when applying fertilizer is faily nice.
One of the principle uses of GPS which I have seen in farming is doing year to year yield mapping. Thats where you have sophisticated equipment on your harvester that does realtime yield analysis (ie. figures out how much corn/soy/etc. you are pulling off the specific patch of land you are harvesting) and associates that number with the GPS coordinates the harvester is currently at. That way not only does a farmer know their per acre yield but knows where each of their good/bad yield spots are quantitatively and can either cross reference that with soil maps or other data to determine the reason for the different yields and if possible increase yeilds.
**AA: a bunch of mindless jerks who'll be the first against the wall when the revolution comes
One university's avionics department put a GPS receiver in each wingtip of an airplane and used them as a bank angle indicator. They just compared the altitude of one wingtip with the altitude of another wingtip.
If you have a ham radio license, you can hook your GPS to a transmitter and experiment with tracking yourself and things. The telemetry standard used for this also allows flagging your position with status information (e.g. "on duty") and weather information. See http://www.findu.com to track hams who are doing this, or google for "APRS".
Just mark your car, ride miles away, and when you're ready to go back, just follow the arrow. No parking near landmarks to remember where the car is.
I'd laugh, if only that wasn't close to home. See, I had a GREAT cache hidden near the Sacramento International Airport, and then that whole 9/11 thing happened and the Sacramento County Sheriff department started patrolling the area around the airport.
Imagine my surprise when cop cars & some guy in a black truck come rolling up on my ass all A-Team style when I pulled over and got out of my car to go check on the cache.
After my heart jumped up into my throat, I showed them the cache, and while they agreed that it was a really neat hiding place, it was not a good idea to continue the cache in that location.
Sad thing is that we used to go drinking in the exact same field years before. No longer. =/
I'm still shocked that the electoral college survived this debacle. I always remember hearing, "Well, if a candidate won the popular vote by a real margin but lost the electoral college, the obsolete electoral system would be abandoned due to the public outcry."
Gore got 500,000 more votes than Dubya. Chads Schmads.
"Imagine," he says, "the end of property crime. Everything that has any value and could be stolen -- a car, a laptop, a piece of construction equipment" (not to mention every ship, plane, truck trailer, and toddler) -- "everything like that will know its location and be able to report it. We can go even further: You tell your laptop that it should only find itself at your office or your home. And if it finds itself in a car trunk, it wakes up, notices that it's in the wrong place, calls your cell phone, and says, 'Hi, this is your laptop. I'm at this location on this map you see. Is that okay?'"
That instantly made me think of the Phrack article on the Low Cost and Portable GPS Jammer. Never know when that baby's going to come in handy.
If these walls could talk they'd probly still ignore me. --MF DOOM
What do you do when the GPS unit breaks or the batteries crap out? Become buzzard food?
Mea navis aericumbens anguillis abundat
You can add your "buddies", and then do things like "where is joe" (down to around 2 blocks) or "find nearest friend" amongst them all. Still haven't really found a practicle use for it, but I guess that's also part of the point of the article: Give users the option, and eventually they'll figure out innovative uses for it.
It seems that more thought actually went into the GPS farming than into many recent computer patents, like Apple's "fast user switching" or any of the other process patents mentioned on Slashdot. Are farmers just not patenting because they aren't in technology? (Or is this process actually patented and it just wasn't mentioned...)
And yes, I think Gore would have done a better job. I think there's a slightly better chance that the WTC attack might not have happened, given I doubt Gore would have closed the investigation into Bin Laden, and I know he took airport and airplane security seriously enough to doubt his usual pro-gun-control views would have lead him to, as Bush did, issue the order banning guns from cockpits.
Clinton's government did, after all, head off a major attack on our airports on New Year's Eve 1999. Or did you forget that too?
Can one "stack" the phone module and the GPS module in the Handspring units, or must one be removed to use the other?
Can anybody explain to me why these farmers get 1 feet of accuracy while I have to struggle with 18 feet maxium accuracy?
J.
I really think 160x160 screens suck for mapping, even in color. Moving up to 320x320, like on some of the Clies that can be had quite cheaply (esp. factory refurbs), adds so much more usability to the maps.
wow, 100 billion. What a nice big round number. Care to back it up? Cause it just SCREAMS "Pulled out of thin air but looks impressive."
Democrats or Republicans. They are both taking us to the same place and they are not afraid of us anymore.
How about this: ABC News
Sorry, teleporters just kill you and then make a copy. A perfect, soul-less copy.
I dont know how many people are aware of it but qualcomm has a suite of products that track trucks and report gps info, engine info, cargo info over satellite or terrestial networks, look for little white domes on the top of the truck cabs those are the receiver/broadcast units. This was recently featured on the history channel. They also have an emercency panic button that wills send an alert to a dispatch center and local law enforcement over satellite
I do recall that 80 billion was allocated in the budget for this particular Iraq war.
A google search confims this.
Whether they've spent it all yet is a bit of a mystery.
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
One of the things that I love about GPS data is that they've pretty much decided on a standard -- the NMEA data format. When I first got my Navman GPS for my iPAQ, I thought it was cool. I thought that the included navigation software was cool, and I thought that seeing my exact coordinates was cool. That could have been the end of it, and I would have been happy.
However, most GPS devices dump their data out in a standard CSV format. This makes it very easy for 3rd party software developers to treat a GPS device as a commodity. Rather than dealing specifically with Garman / Navman / etc, they just read the standard. It's great.
It also makes it trivial to write your own apps that interface with a saved data file. I wrote a really small app to overlay a car trip on a map, including red dots where I stopped. Now you can really say, "I'm serious -- look at how bad traffic was!" I've heard of other innovative programs, too, like correlating the timestamp on a picture from a digital camera with the GPS log to give you the coordinates where the picture was taken.
The most useful GPS data is the "RMC" string:
If you're interested, the data format is here.
It all goes downhill from first post
There's a ton of MS source code geocached, you just need to visit the right websites to find it.
Longitude: -122.13099913, Latitude: 47.63839512
It all goes downhill from first post
I want a PDA-like thingy with these features:
1. Cell phone
2. Runs Linux
3. Instant messaging
4. Computer (PDA, web browser)
5. GPS-capable
6. Easy link-up to desktop
7. Under $500 because I know I will drop and sit on it on occasion.
When will this be available for the huddled masses like me? I don't even need color.
Table-ized A.I.
We had to pay $60,000 for a rack mount GPS unit for the research ship I was on. We only got 2 or 3 satellite fixes and even then that was for only a handful of hours a day because the constellation wasn't complete. But by cracky we loved it! It was good enough then and by god ... by god... what we wouldn't have done for one of those modern sub $200 contraptions. Oh yea and a full constellation of satellites.
Navigation for scientific research (gravity & magnetic surveys) was interesting. We'd post process and combine a few hours of GPS a day, Transit Sat Nav (crude sat fixes + dead reconing), plus ARGO ranging navigation. The cool thing about ARGO was that it required shore stations where someone had to be by the transmitter for several weeks. And since the cruises were in the Carribean and off Brasil, sitting around a shore station (aka "the beach") for several weeks was pretttty fine.
Sure, as long as my wife can't use it to hunt me down. :)
Nothing to see here; Move along.
Actually, the PPS transmits the P(Y) code on both L1 and L2. That's how the military gets better accuracy: the 2 different frequencies experience slightly different amounts of ionospheric delay, and by measuring this difference it's possible to correct for the delay.
more satellites in view = better positioning accuracy
This is not strictly true, since the position accuracy depends a lot on the relative position of the satellites you are taking a fix from (if they're all bunched up then you will experience significant dilution of precision). More satellites in view may increase the likelihood that you'll get a favorable geometric configuration. But it doesn't always, which is why the current GPS constellation is optimized to provide good geometric configurations, instead of to maximize the number of sats in view.
To make matters worse, some cheaper GPS receivers just grab data from the first 4 satellites they detect, and satellites that are directly overhead will have (slightly) stronger signals than their counterparts near the horizon as a result of the smaller amount of propagation loss and atmospheric loss their signals will experience. So there's a good chance that a cheap GPS receiver will take a fix from a bunch of satellites directly overhead (particularly with many more satellites in the sky to form that bunch), even if a more favorable configuration is in view, and end up with a much lower accuracy than they should. That said, I believe that most newer receivers look at all of the satellites in view, and pick the best 4.
Also GPS is being heavily upgraded. They are adding a third signal with M-code(L3), and adding C/A code on L2.
This isn't entirely accurate. M-code will in fact be on transmitted on both the L1 and L2 frequencies, not on L3. You're correct about the extra civilian signal on L2 (designated L2C), although I'm not sure if it's identical to the L1 C/A code. There's also another civilian signal that will be broadcast on L5 - this one will be primarily for aviation use and "safety-of-life" applications. I don't remember what L3 is being used for, but I'm fairly sure it's not going to have any kind of navigation code on it. Check out this article in the Aerospace Corporation's online "Crosslink" magazine for a nice overview of GPS modernization.
I'm pretty confident that this is not true. Frequently the phones only include part of the GPS receiver, depending on the cell tower to do calculations and signal reception.
More importantly, I've read every manual I could for phones with E911, and the only option you had was to allow non-911 services (ie: advertisers, or other as yet unknown services) to use it.
If you want a phone with a GPS, Nextel is the only way to go. They have phones that run J2ME java stuff, and you can access the GPS via a Java API. Unfortunately, the price for their data service is too high, and you can't use bluetooth on any of their phones.
Have a look at the Gotive
threadeds blog
Using more than 4 satellites does improve your position accuracy, this is generally called an "over determined solution". When SA was enabled, the benefits of this were nullified by the inaccuracies introduced by SA, but today that is not the case. Im sorry about screwing up the signal schedule, its late :). The L5 signal (what I should of said when saying L3) is going to be a long period PRN code without a data message modulated on top. Current C/A code has a period of 1ms with a 50Hz data message modulated atop of this. The unknown data message bits prevent a pre-detection integration time of 10ms, and a tracking integration time of 20ms. This limits the performance of low-level acquisition and tracking (ie indoor or space case). The L5 signal, with no data message eliminates this barrier. The new satellits going up are also going to have better atomic clocks, further improving user end accuracy. Finally C/A on L2 are going not going to be of the current Gold Code type, the details are not yet released publically.
not to nitpick, but GPS uses triangulation as well =)
Yes, I'm familiar with the concept of an overdetermined solution. But you only get a benefit if those 4+ satellites are in a good geometrical configuration relative to each other. Making the assumption that just adding the Galileo sats will automatically improve position accuracy (as you did in your previous post) is incorrect. If you have, e.g., 5 satellites in view, but all are within 30 deg of each other and directly above you, you will get worse position accuracy than you would if you had just 4 sats that happened to have a near 90 deg separation. As I said before, that's why the current constellation is not optimized for number of sats in view. Initially they were planning on using a symmetric constellation, but found that the were getting bad dilution of precision, even with 6 sats in view, due to the relative position of those sats. That's why the current GPS constellation is a carefully designed asymmetric constellation - the slight offsets in the sat position from a symmetric constellation help to guarantee good geometric configurations. Just adding extra sats into something so carefully designed will not necessarily improve things.
DanCar Autosikring
The base units tracking software carries out conversations with the vehicles alarm unit (which contains a GPS module) over SMS and uses M$ MapPoint to display the current position. Also the state of things like tilt alarm, crash alarm, temperature, tire pressures, well it all depends on what other modules are plugged in really.
It can be used to track several vehicles in real time (accepted the SMS message round trip being about 15 seconds usually if in country, and about a minute if the vehicle is in another country)
It's been available for a few years now, it used to use AutoRoute but I got fed up with the SendKey nonsense so it uses MapPoint now.
threadeds blog
Go Boilers! :-)
DanCar do a unit with your requirements.
When an alarm is triggered it will phone up and a voice synth will tell you what is wrong, alternatively an SMS message, or both, to as many as ten different numbers.
You can then use some pc software to follow the car in real time on a map.
threadeds blog
According to www.costofwar.com, the estimated cost so far is at the moment almost $68 billion, though quite a big part of it is the future interest payments. The cost of the occupation is $4 billion a month ($6 billion with all the interests included), as Rumsfeld stated in a reply to the Congress. The $100 billion line will be reached quite soon...
Hell is not other people; it is yourself. - Ludwig Wittgenstein
Also worth noting is how GPS, like computers, wasn't adopted overnight, but rather over time as applications were found.
something I post a couple days ago
--
Handspring unit GPS magellan - 12 channel - $49
Good mapping software for $29
Sprint phone module from ebay for $20
Calling your friends from a ditch because your GPS was wrong: priceless.
Is that $9 Billion dollars in 2003 US$? If not, the GPS jumps up in price. I still would rather see money spent on GPS, than the EPA releasing a report reccomending how long our candle wicks should be.
You know, the only person I remember at Purdue who worked on GPS was a fellow named Jim Garrison. As I recall, he also worked at Goddard at one point, and his research involved measuring reflected GPS signals.
You two should get together and chat. I imagine you'd have a lot to talk about.
I am getting soooooo sick of the French bashing.
Too right! If it weren't for France, you'd all be speaking English right now!
"Goodness me, how unlike the FBI to abuse the trust of the American public." -- The Onion
You can't seriously tell me you would want Gore running the war against terrorism? We would all be dead by now...
May be we will be more successull finding the weapons of mass destruction. really think that We would all be dead by now...? Some soldiers may be alive. The US external image would be not so bad and US citizens may have keept the right to a judgement in cases of terrorism.
I can't say that GORE would have been better, but I' sure that somewhere there must be a better president.
You seem to forget that the Galileo constellation, while utilizing nearly the same inclination as GPS, is going to consist of 3 totally different oribital planes. Being in different orbital planes, the probablity of having a GDOP conducive to a good solution is much better with 48 satellites in 7 different planes rather than 27 in just 4.
mmm you may start considering something called books.
Actually I work with Prof Garrison. I'm on his research team. How do you know him?
I'd like to think that the Galileo developers have worked with the GPS planners to make sure the two constellations play well together. However, while the initial acrimony over Galileo seems to have abated, I'm not sure how much actual cooperation is going on.
BTW, the GPS constellation consists of 6 planes, not 4.
Put your bias aside for a minute and realize that 9/11 didn't happen because of 8 months of the Bush presidency but an ongoing hatred of the United States that was evident back in the 1993 WTC attacks. Gore being president wouldn't have reduced the chance of 9/11 happening, the only question would have been our response.
given I doubt Gore would have closed the investigation into Bin Laden
The investigation had been going on for some time. You can argue theoreticals, but there's no particular reason to believe it would have been more successful in the 8 months leading up to 9/11 than the years prior. Plus, 9/11 apparently would have occurred even if Bin Laden had been captured since underlings were actually organizing and executing the attack. It's doubtful a Bin Laden capture in 2001 would have avoided the 9/11 attacks. A capture in 1995 or 1996 might have, though.
Clinton's government did, after all, head off a major attack on our airports on New Year's Eve 1999. Or did you forget that too?
9/11 wasn't planned, funded, and executed in the 8 months of the Bush presidency. So apparently Clinton's government succeeded at heading off the airport attack(s) [I had only heard about LAX, was unaware of other airports?], but they missed the upcoming WTC attack despite one having already occured back in 1993. They missed the Cole bombing as well as the two attacks on our embassies. 1 out of 4. They're batting 0.250.
So be it. If a company can't figure out a way to charge for their service, then they go out of business.
You seem to have the impression I don't pay for satellite, I do, in fact my satellite bill was recently over $130 until I cut back and cancelled some of the premium channels. I use satellite Internet also.
I pay for it, and yet see nothing wrong with tuning it in without paying. Ponder that one for a while.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
Thank you AC
Bill
bamph
LMAO... I can't believe this joke is moderated as "Insightful". :)
..and its not that expensive.My dad used to have the service on a truck he sold some time ago.
Its very common nowadays for people to hire this services down here.
I guess its cheap because of high demand and because car robberies here are extremely common.
So now the robbers are opting to kidnap you with your vehicle to prevent you calling the GPS company or the cops...
Also some people have told me that the robbers can just take the car and quickly move it to an underground parking garage for a while or into a container to prevent location.Dont know the veracity of that though...
You can download a Java App to track your cell phone at www.gadgeteer.org I have a free service running that recieves UDP packets sent by the phone and creates a web page with a link to mapquest showing your current location
Free cell phone tracking
Anonymous coward posts the obvious followup, stating "unelected? check"
But of course, screwing that up. George Bush was elected. I mean, duh.
Getting a majority of the votes cast nationwide is not the criteria for getting elected.
All you monkeys stating otherwise are part of the problem. If you understood how our system worked maybe things would have been different. At least there would be less whining.
The US is not a (pure) democracy, and speaking as someone who is a member of some minority groups, I'm glad it isn't. For those who aren't from the US, it is a constitutional republic, where a certain measure of power is left to each of the 50 states. This prevents, say, California (the granola state) from riding roughshod over, say, Kansas (the carry on my wayward son state).
.signature: No such file or directory
You would know the answer if you bothered to read the article:
The system has cost $9 billion to develop, launch, and sustain over 30 years... Today, the GPS industry in North America is estimated at $4 billion a year.
Not a bad investment of your tax dollars and mine.
Furthermore, the French sustained MORE losses than the (obviously much larger) United States in World War II, on the heels of devastating losses in World War I (in which the U.S. suffered relatively few casualties as a latecomer). And that doesn't count hundreds of thousands of civilian losses. Anyone who thinks the French folded easily and without losses is an ignoramus.
I am getting soooooo sick of the French bashing. Look, if it hadn't been for France bailing your asses out 250 years ago, you'd have continued to have your "country" run by some unelected idiot called George whose only qualification to the job was that his father did it. Thankfully the French were there to help you defeat King George III, and you avoided that situation.
:P The reality is that we both had a common enemy at the time, so we cooperated.
You have a very strange view of history.
So exactly how many soldiers did France send over to the US to help out?
Yeah, that's right.
It was helpful that France was also at war with England, but it's not as though France sent a sizeable portion of their army over to help us. Besides, you could argue that France would have lost that war if it wasn't for us Americans
It not like the US surrendered to England and the French had to come over here an save us.
Life is too short to proofread.
That's a good point. However, my argument was with your blanket generalization that "more sats in view = better position accuracy", which, as I said before, is not strictly true. Just adding more orbital planes will not necessarily lead to improved GDOP performance.
I wouldn't be so sure about that. It seems statistics come into play here. Even if you only have 3 satellites, having 5 measurements is going to be better than having 3 (the more measurements you have, the more random error you can remove). Say you had 5 satellites, but 2 of them were right next to other satellites, this could be treated as the situation above (somewhat). Correct?
Technically, more satellites should always improve your accuracy, even if you were adding one right next to another.
Perhaps that's not true from a positional point of view, but it's definately true from a timing point of view.
Life is too short to proofread.
http://www.aprs.org/
http://www.aprs.net/ and http://www.findu.com/ have some neat APRS interfaces.
retrorocket.o not found, launch anyway?
I would be. Yes, more measurements allows you to average out statistical noise. But the position error we are talking about is what is known as Geometric Dilution of Precision (GDOP). That kind of error is caused by having the satellites in view in a non-ideal (i.e. non-orthogonal) configuration. The errors are not statistical, but inherent in the geometry - averaging or filtering will not help.
Technically, more satellites should always improve your accuracy, even if you were adding one right next to another.
Only if you are assuming the exact same geometric configuration, but with one extra satellite. Otherwise your statement is not true. If you have more sats, but in a worse configuration, your GDOP will be worse, and you'll get lower accuracy. If you go ahead and make the assumption that the sats are in "the same configuration with one extra sat" you have automatically invalidated the generality of statement "more sats in view = better position accuracy". Which has been my point from the get-go. Please go back and read my earlier posts - I never claimed that more sats will inevitably lead to worse position accuracy, only that the "more sats in view = better position accuracy" statement was not true in all cases.
Perhaps that's not true from a positional point of view, but it's definately true from a timing point of view.
If you will examine the previous posts you will find that we were talking specifically about position accuracy, which is where GDOP comes into play. Timing accuracy is a different issue.
If you go ahead and make the assumption that the sats are in "the same configuration with one extra sat" you have automatically invalidated the generality of statement "more sats in view = better position accuracy".
I see your point now. You could have 5 sats with poor GDOP or 3 with better locations.
While you valid have a point there, it seems like you're spiltting hairs. Yes, in some arbitrary math problem you could have more satellites, but less accuracy, but taking the current GPS constellation as a given, any additional satellites are going to improve your accuracy. I think it's reasonable to assume "same configuration with one extra sat" since they aren't planning on shooting any down.
That said, you're right.
Life is too short to proofread.
If your activities depend upon GPS (are not simply assisted or made more convenient by it) what happens when/if GPS fails?
I.e., if 911 emergency services depend upon GPS and map/direction assist systems in order to find your burning house, what happens if GPS fails for some reason?
I know GPS is built to be redundant, but business (or other activities) that _depend_ on GPS should have a "manual" backup when possible.
First off, GPS is a military thing that civilians have piggybacked on.
Secondly, those freeloading, "mooching" foreigners have started developing their own GPS systems, and the US has actually balked at this happening. Out of passing curiosity, why do you think that's happening? (Careful not to concentrate on this question too hard -- you don't want cognitive dissonance to blow any noggin gaskets.)
Remind me to try to sell you something sometime. You've bought a world view that's based on ridiculously oversimple "government is bad!" rhetoric. I'd place money that you have no idea what your real, individual tax burden is, but that doesn't seem to keep you saying they take a third. You're offering ten bucks a month for GPS when, say, the whole of NASA very likely doesn't get that much of your tax dollar -- they take about $1 out of every $1000 in the federal budget, to give you some idea how that works out. That's one lavish GPS system. I'd love to be a used car salesman when you walk through the door...
"Fundamentalism" isn't about divine morality. It's about human authority.