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GPS and Portability?
curious george asks: "I've always loved knowing exactly where I am in the world and it's becoming easier with the mainstream application of GPS receivers and other integrated technologies available on the consumer and prosumer market. However, finding those awesome accessories that seamlessly integrate with the laptop, mobile phone, or PDA are incredibly difficult. Does Slashdot know of any gadgets that can add the GPS capabilities found in most new vehicles to the mobile geek? Infrared, Bluetooth, USB, and other methods are abound, but what about compatibility between the Mac, Windows, Linux, and Symbian operating systems?"
I've got a Deluo USB GPS that works great on my Linux box. It's effectively a serial GPS, with a USB/Serial adapter (supported in Linux) built in. My wife has borrowed it and used it on her Mac OSX box as well, and of course, I ASSUME it works in windows since it comes with a disk of windows drivers and software.
I see they make a Bluetooth GPS now, too. If it works as well as the USB one does, I'd consider it...
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and I work developing mobile GPS enabled applications.
I'll take a stab at what I think you are looking for, but you're asking a question that is way too general. It's like walking into a group of geeks and saying "tell me about this computer stuff".
Pretty much all GPS's put out NMEA strings (or in some cases they can be configured for their own proprietary language in addition) on RS-232. In cases where there is no serial port (e.g. a CF card) a serial port is 'added' to you system when you insert the card. This "everything is data coming from a serial port" makes life easy for software developers. NMEA strings/RS-232/4800 bad is the standard, which I think comes from the marine industries (NMEA = National Marine Electronics Association -- they make sure your GPS can talk to your fish finder). This pretty much covers basic GPS functionality (getting heading, position, satellite status). Different manufacturers have their own protocols for advanced functions like waypoint transfers etc.
I've never heard of a USB based GPS; there's no reason it couldn't be done, but there is no reason it needs to be done, at least until RS-232 goes the way of the dinosaur. It's even possible to power the GPS unit parasitically off a laptop RS-232; Delorme used to bundle a puck shaped unit that did exactly that with their street mapping software.
A word of advice by the way; as somebody who has tested various vehicle mounts and software, I strongly recommend against using them while driving, even if you tell yourself you are just going to glance at the thing now and then to make sure it is working.
There are bluetooth GPS units. In theory they're great but we've found that the pairing is somewhat flaky. In any cases, supposing the problems we've had with the BT units are an anamoly, I'd say we haven't really found a reason to use them other than their cool factor, which is hardly justified by the price differential and the fact they just don't work 100% reliably. We stick with either CF card format GPS, PDAs with integrated GPS, or if we have a fancy survey grade device good old RS-232.
The only other thing I've run into other than RS-232, CF slots, and bluetooth are ultra cheap OEM units about the size of a quarter that output NMEA on a single TTL line (0-5v). This can be plugged into a laptop RS-232 and it will work OK, but PDAs will often fail to read them, because RS-232 requires both positive and negative relative to ground (I dont' recall, I think it's somethign like +/- 24v). Robotics folks will be familiar with this TTL-to-RS-232 interfacing problem. In any case, when you run into some kind of OEM unit with integrated GPS, and you can't read it with a PDA, chances are you're talking to one of these beasties.
WRT devcies, Garmin has palmOS device that looks cool, and there's an outfit called Mitac that has a device called the Mio that has a very slick PocketPC with integrated GPS. The Mio is very comparable in size and styling to current generation iPaqs. We've been testing the Mio the last few days, and my take is that while the screen is excellent for indoor use, like many such devices it is very hard to read in the sunlight. It's got fairly slick looking software, but we havent' used it for real, so YMMV.
If you are going for toy value, I'd probably look at a Mio. If you are going for GPS to save your life, then a high quality, regular handheld GPS is you r best bet. If you are going for cost effective data collection, go for a PocketPC unit with a CF slot for the GPS and a SD slot for a backup memory card. If you are going for mission critical data collection, a ruggedized survey grade unit like those sold by Trimble is what you are looking for.
Don't even get me started on software. There's really so much to talk about there's nothing to say unless you're a bit more specific about what you want to know. Are we alking surveying (as in civil engineering)? Finding the nearest Indian restaurant? Geocaching? Work tracking?
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I have the generic model BU303 USB GPS receiver which you can buy from ebay for around 40 - 60 bucks.The guy ships from hong kong.
It readily works with my debian box.
The mapping software available for GNU/Linux is non existent.I know http://www.gpsdrive.cc/index.shtml(GPS drive) is available but it does not have features like auto-routing/street -level maps which are absolutely essential for driving.
Expedia is currently the only "Automatic" download option in GPSDrive (there used to be an option to grab USGS Topo maps from "Topozone", but they complained so it's been removed - They weren't QUITE in the right projection for GPSDrive anyway). GPSDrive can work with any map image that is the right size and projection though.
I haven't managed to figure out what projection the "street" maps are in (someone on the mailing list opined that they thought it was a "Miller" projection, but nobody who knew for sure has ever been enticed to post the information in the GPSDrive mailing list that I can find - that's the reason I was asking about the Expedia map projection in an earlier post), but the "Topo" maps are "flat" (or "equirectangular" or whatever term you want to use), meaning each pixel is exactly the same latitude and longitude) ever since the NASA satellite data was added as an option to GPSDrive. Maps need to be 1280x1024, in a graphics format that GTK2 can interpret, and you need to know the "scale" and latitude/longitude of the center of the map.
There appear to be free maps of Canada available here. If you can convert them to the appropriate size and format, you can just stick them in ~/.gpsdrive, add them to the map_koord.txt file and GPSDrive will use them.
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Get a Nokia Mobile phone with built in GPS.h tml
http://www.nokia.com/nokia/0,4879,53751,00.
Also doubles as a Mobile Phone.