Dude, where's my car?

February 19, 2005 12:17 AM

Can I have my car send a GPS signal to my web site to let me know where it is?

I mostly take public transit to work, so there are often gaps of several days between times that I drive, and I forget when I parked. This is a problem because I get tickets for parking during street cleaning, etc. I want my car to send a signal that would update a map on my web site. (I know there are less involved ways to solve this problem, but what kind of fun would that be?)

posted by kirkaracha to travel & transportation (8 comments total)

GPS is one way only. Multiple Geostationary satellites send signals at timed intervals allowing a GPS Receiver to triangulate position.

You could use a handheld GPS or GPS equipped PDA when you park to check and log the longitude/latitude for future reference though.

Npw that I think of it, Onstar uses a combo of GPS and cellphone services to track vehicles. Maybe there would be a cheaper way to set this up, but the service itself is only US$16.95/month for a properly equipped vehichle.
posted by HyperBlue at 1:05 AM on February 19, 2005

I read a story about a guy who used a GPS enabled cellphone to track his ex-girlfriend around. A google search yields tons of promising looking links. You'd probably need to write the final piece to publish the tracked data to your website, though.
posted by delmoi at 1:39 AM on February 19, 2005

With a morse code-free technician amateur radio license, you could use APRS.
posted by OneOliveShort at 2:23 AM on February 19, 2005

kirkaracha, i have a low tech solution (i too suffer from "where the hell is my car"). get a dog. i always surprise myself on the mornng walk ("look, there's my car!").
posted by heather at 2:50 AM on February 19, 2005

Something like this might work; a google search on GPS tracking device turns up a number of other potentially useful hits. They all seem pretty expensive, though.
posted by TedW at 7:21 AM on February 19, 2005

Nextel has a handset with a built-in GPS unit. Many Nextel phones also support some form of Java. You may be able to write an app for that phone that queries the GPS unit and then sends a message back to your webserver.

There are a lot of design decisions to make along the way that depend upon why you are doing this and how much money you want to spend.
posted by b1tr0t at 6:14 PM on February 19, 2005

There are any number of technological solutions to this problem. However, you may consider writing down where you parked every time you park. Get a pad of paper for the car, and put some sort of reminder on your keychain, maybe a pen? You need some sort of "forcing function" to get you to write the note, and it has to be dead simple and fast.

Maybe snap a picture with a cellphone camera every time you park? That would be quick provided you already have the right equipment.
posted by RikiTikiTavi at 10:51 PM on February 19, 2005

It depends how technical you are. I think the solution with the best price/performance ratio is to get a bluetooth cell phone with an unlimited data plan, and combine it with a small bluetooth-enabled computer with an adapter so it can run off of 12V DC. For example, the Mac Mini might be a good platform for this (depending on its power usage), although its hard drive might not like the G shocks of potholes, etc.

Another option is to find a small embedded linux box with a flash hard drive (see linuxdevices.com for a bunch of these), and use the linux bluetooth stack to let your cell phone connect back to a central server over WAP or a similar protocol.

As far as the GPS goes, there are a couple bluetooth GPS units out there that broadcast the NMEA location data over a virtual serial port (i.e. you can just parse the simple lines of text coming from the unit and grab your location). I have one made by Emtac, and these units typically have optional 12V adapters. I've used JSR-82 (the java bluetooth api spec) with the gps, but not from a java cellphone or embedded computer yet. It's relatively easy to write a java gps-enabled app when you combine J2ME with the JSR-82 apis, at least compared to slinging around C/C++ code.

Something to consider is that you don't need to have a lot of UI or smarts on the car side, all you need to do is get a location fix and send it back to a central internet server, which can then decorate and display the data any way you want.

There will be battery issues to consider, and you'll probably have to attach an external antenna to your gps in order to receive the signal reliably since the receiver is going to be inside your car and behind sheet metal. Also, I wouldn't count on the bluetooth signal going more than 6' inside a car, so that might affect where you choose to install everything. I'm thinking the trunk would be best (similar to how audiophiles mount amps/subs in their trunks), and it makes for easy installation of an antenna. The antennas aren't like those trucker CB antennas, they're pretty small and will fit unobtrusively on your trunk.

If you're not a hardware/software person, then there might be some open source projects doing similar work, and if not, there will be in the next year or two; vehicle-based computers/apps should take off as more manufacturers start offering smart systems in their cars. Five years from now, Slashdot will have an articles about some geek who made a custom HUD for his car that projects RSS updates from his favorite websites on the road as he drives to work...

The bluetooth gps plus embedded computer setup for vehicle use will be pretty expensive ($700+). If you know the gps will always be in your car, there are cheaper non-bluetooth gps units that you can attach to a linux box with a serial or usb cable. A good gps will be at least $100, and a serviceable embedded linux box will be around $400-500...
posted by beaverd at 11:01 PM on February 19, 2005