Location Tracking

ukchris · 11-14-2004, 07:19 PM

There has been discussion on and off about wanting to transmit the location of your car using it's GPS to let people know where you are or for you to track your vehicles. It seems not this shouldn't be too hard but I was wondering, how and where would you want to send it?

If we assume you have a program that either on a scheduled or on demand basis identifies the LAT/LON of where you are then where should it go? Post it to a form handler on a web site? Send an email? Send an SMS?

It seems to me the LAT/LON themselves are not much use, as such you really would want to build it into a link to a mapping site and send it to someone, either by email or log it to a database on a web server. Thoughts? I've been experimenting with logging to a MySQL database through a PHP page and having another page dynamically build links to a map site.

C.

Ricky327 · 11-15-2004, 01:52 AM

I dont know if you seen the discussion about the tracker I have been working on. It work very different compared to most poeples approach to the problems.

It may give you some idea, but here is a quick description if you havent seen it before :

Its a standalone unit controlled by a PIC MCU. It uses the carPC GPS receiver together with a pay-as-you-go phone not on contract, no modem and no credits.

The way it work is very simple.

The controller converts the LON/LAT information comming from the GPS receiver into FSK tones. The position does not update at 1 per sec due to the limitiation cause by the voice bandwidth/compression done by the mobile phone. The FSK can only be run at 300bauds max for reliability and so limits the position update rate to once per 3-4 secs. This FSK tones are then fed into the MIC input of the mobile phone for transmission to the receiving end.

The receiving end then converts this FSK tones back to the proper NMEA sentences that carries to LON/LAT position. This NMEA sentences is of course presented to the comport of a desktop PC and a GPS s/w is run to plot the position of the car being tracked. The FSK tones comming out from the landline/mobile phone speaker can also be decoded by a sound card with a s/w analysing the tones, converts them back into the NMEA sentences ready to be outputed to a virtual comport.

The receiving end calls the tracker and its the one that pay for the phone call during the tracking time.

As you said, talking about sending LON/LAT to the receiver without a map is almost useless unless theres a way to plot that location on the map.

If you intend to send by SMS why not use the mapdata of the GPS s/w on the carPC to find the current location of the car before sending the info to another phone? so atleast the road/area/speed/heading can be passed on as a text messages. I dont think its easy but its just a thought.

as such you really would want to build it into a link to a mapping site and send it to someone, either by email or log it to a database on a web server.

Why do you really need to do that? cant you use a GPS s/w to plot the LON/LAT. Do you want to be able to track the car anywhere as long as an internet connection is available?

I think you really have to decide if you want live tracking or just wanting to know where the car had been. Following someone from the info on email or sms is not gonna be easy.

ukchris · 11-15-2004, 08:31 AM

Thanls for the reply, it's interesting how things develop in different if parallel ways.

My aims really are two-fold. I want to be able to track where the car has been in a file on the CarPC and then also havbe an option to schedule updates while travelling. The latter is really more focussed on finding out where someone is right now (or at the last update).

I don't want to use the GPS software as there are too many variations, also Destinator is really the only one with an SDK. I think for now I will just bring up a GPRS connection, transmit the location and drop it.

I think email or a dynamic will work as the recipient then doesn't need any software, all they need to do is click on the link they receive. I wonder though if people will want to or be able to build their own form handlers etc or how much of the logging / mapping element they'll neef doing for them.

Chris.

Ricky327 · 11-15-2004, 08:47 AM

I don't want to use the GPS software as there are too many variations, also Destinator is really the only one with an SDK. I think for now I will just bring up a GPRS connection, transmit the location and drop it.

Its best to just transmit the location at which ever way you wish and bring them onto the comport of the desktop that monitor the location....this way any GPS s/w can be used to plot the location, no need for SDK and such.

One member called magpie if I remember it well has been working on a simliar project as yours. Do a search im sure you get some more ideas.

ukchris · 11-15-2004, 05:02 PM

Well... progress!

I have it at the stage where my app tracks the GPS location and then at the click of a button is able to bring up a GPRS connection, send an email and rop the connection again. There is an options page for all the various elements, my aim is to have a "Connect, Send, Disconnect" button but I need to handle the time between telling it to connect and the connection being ready.

Once that's working the next step will be a timed option to tell it to send the location every 30 seconds or every minute, also an option to post it to a web server so it can be more widely accessible.

Chris.

GruvThang · 11-15-2004, 05:29 PM

very nice!

0l33l · 11-15-2004, 06:52 PM

Quote: Originally Posted by ukchris

Well... progress!

I have it at the stage where my app tracks the GPS location and then at the click of a button is able to bring up a GPRS connection, send an email and rop the connection again. There is an options page for all the various elements, my aim is to have a "Connect, Send, Disconnect" button but I need to handle the time between telling it to connect and the connection being ready.

Once that's working the next step will be a timed option to tell it to send the location every 30 seconds or every minute, also an option to post it to a web server so it can be more widely accessible.

Chris.

Looks like its in Delphi

ukchris · 11-15-2004, 08:27 PM

It is indeed, is there any other way?!

0l33l · 11-15-2004, 08:45 PM

Quote: Originally Posted by ukchris

It is indeed, is there any other way?!

Want voice integration?

Tred · 11-15-2004, 09:06 PM

that is nice! One suggestion, instead of logging lat/long coordinates every 30 secs why not have it continuously log into a small file? .txt, .csv maybe? Is there a way to run an array of coordinates through gpsvisualizer or motionbased? This way you can collect and display more sampling data everytime you connect.

Also how are you connecting to the internet? The prepaid phone idea sounds great. I know they have ALOT of those around in London since you only need to swap the chip. Here in the US its more of a pain in the ***.

Is there a way on your program to automatically connect and upload a file whenever an access point is found?

ukchris · 11-15-2004, 09:14 PM

Tred...

Have a look at my thread under Software Development, search on motionbased or gpsvisualizer and you'll find it, doing exactly that, maybe I should have posted under GPS.

I'm connecting using GPRS via Blurtooth but it is largely irrelevant, it can work over any connection. I have done some testing one working with hot spots as you drive through them but the consensus seems to be that you don't have time to lock in before you're on your way out again. It does work well for pulling offline web pages down as you leave home though, I have half done project for that too.

The unfortuate part is that I'm better at starting projects than finishing them, but I'm trying!

0l33l · 11-16-2004, 01:47 AM

Quote: Originally Posted by ukchris

The unfortuate part is that I'm better at starting projects than finishing them, but I'm trying!

I have that problem too

But it hasn't occured with NaviVoice, its so fun developing it. Always something new to add or fix

leckan · 03-05-2005, 04:46 AM

is it possible to make a soft like find u / find me for pocket pc wich is free
with this software u can track your car for free but it only works with pocket pc.

http://www.geocities.com/oxcarz12/