The Arduino can talk over a wide range of networks. Ethernet, Bluetooth, Wifi, XBEE and GPRS to name the most known. I had a Telit GM862-GPS module laying around, unused for some time already. It has GPRS and GPS capabilities, both accessible with AT commands. So I decided to port some of my code to the Arduino.
Some weeks ago I met Thilo and he showed me twibble, his GPS enabled twitter client for the N95. Nice little and smart application. It sends messages with geo positions to twitter. The postion can then be tracked and viewed within Google Maps.
I was impressed and decided immediately to try to post the same messages with my mobile tracker and use the same, twitter, twibble and GM, to track my positions.
After some trouble with my SMS sending routine I am finally able to show some working code.
Features so far
- Displays menu via serial port if attached to PC
- Can run unattended or interactively for debugging
- Fetches GPS positions and sends them via SMS every two minutes
If the circuit is powered on, the following sequence will be executed:
- Boot up, switch on the GPS-GSM module
- Initialize the modem
- Fetch the GPS position, redo until position is fix
- Parse and format position
- Send formatted position as link to Google Maps as SMS
- Wait 120 seconds
- Goto 3
Well, now you have all information and sources to rebuild and program this device, at least you should. If not, please tell me, what is missing.
But I had some hints in the comments that this can be done easier with the built-in Python. There also other very promissing sources and that is definetely the next thing, that I want to try out. If that works fine, which is not really doubtful to me, I could drop nearly all the external components. That would make it cheaper, easier and smaller.
Nevertheless, the firmware can be useful, if you would like to see, which commands to use to talk to the Telit module.
Two weeks ago I posted about how to interface an AVR microcontroller to a Telit GM862. You can read it here: Interfacing an AVR controller to a GPS Mobile Phone.
That post got listed on Hack-A-Day, Engadet and Makezine among many others! w00t! Thanks for posting and reading it, I really appreciate it.
This post will show you, how to use this equipement to send an SMS with your current position and how to display it in Google Maps.
Update: Part II Using Google Maps with a Mobile GPS Tracker is online.
My goal is to build a kind of a mobile tracker. There are many different use cases you can think of but one of the obvious is a device, that is able to report where it is. This device can be put in your car and it could trigger an alarm, if the car got stolen. Actually it could tell you where it is.
There are already mobile tracking devices out there, but they seemed to be too expensive and too closed for my needs. Another option is one of these new Nokia N95 which have built-in GPS. They are really nice, but about 600€, which is not a bargain. So I decided to do my own.