DIY GPS tracker

[ddlooping]

End of the day it works...

Just to make sure, the iPod would have to be in an area covered by wifi, right?

Im missin something here.

Whats a GPS tracker do, tell you where you are?

In this case, it can be used to locate your bike, which can be quite handy if it's been stolen.

Whenever you call the number of the sim card, it will respond with the coordinates of its location via a SMS message. Like "Lat:N22.576685, Lon:E113.916565, Course:200.78, Speed:0.1018, DateTime:11-05-26 15:14:46". You can then use these coordinates on google map which will show where exactly the unit is located.

[Cynic]

Very few phones have a GPS chip, the phones use the transmiters to triangulate their position same as has been done since the war. Try taking an i phone to a bad signal spot and trying the 'gps' system.

It then converts it to whatever your needing, a clever gps style co ordinate or a spot location on a map.

The overlap between wifi providers means the uk is well covered, Providers like mobile me for example transmit the lost signal to your ipod globally like text messages. The important bit is the location apps cost money as the phone has to keep pinging the transmitters to check its location. The wifi system doesent cost but works the same way.

Its also passive so uses minimal power on the i pod, and ultimately your bike i suppose.

Have to admit it has got me thinking, i fix i phones and such, changing screens, lcd's battery's, general repairs that kind of stuff as a side thing and it wouldn't be a whole heap of trouble to bury one in the seat foam for example.

[ddlooping]

Have to admit it has got me thinking...

Good.

[ddlooping]

I had a look at the bike and the battery compartment seems like a good place to "hide" the tracker.

It would also make it easier to connect to the battery.

[ddlooping]

Update:

I've just received the tracker.

Once set-up (it took less than 10 minutes), I sent it an SMS asking for its location.

I received the following SMS back:

Precisely Locating:http://maps.google.com/maps?q=41.73806,0.496035

The precision is about 10 meters. Hopefully enough to locate the bike if stolen.

Some of its untried features:

1) You can set it up to alert you via SMS if it moves outside (or inside) of a perimeter of your choice.

You simply give it a center (latitude, longitude) and a radius (in multiples of 100 meters).

2) It will send you an SMS to warn you when its battery is low.

When it's too low it will send you another one and power off automatically.

3) If you call it and let it "ring" for more than 10 seconds it will go in "voice" mode so you can hear what's happening around it.

...

Edit: I changed the latitude and longitude in the coordinates I posted.

[ddlooping]

I've just sent it the command "WHERE#" via SMS.

The reply I almost instantly received...

Lat:N41.738032,Lon:E0.495960,Course:176.21,Speed:0.5518,DateTime:12-03-22 01:28:45

Some more thorough testing needs to be done but me likey so far.

[Paulwhite]

ok so its a good/brilliant idea! could be worth a step by step guide! but can anyone else access it if they wanted to? say if a thief knew that there was one installed on a bike could they gain access to its where abouts? what if your phone was stolen by a thief and they used the app....could they then find your bike or even track your movements? also what if some firm rings the phone (say ppi people) when its been nicked and you cant get through or the thief hears it ringing?

[ddlooping]

Received the following SMS after having armed the tracker for motion detection.

Vibration Alarm:http://maps.google.com/maps?q=51.73804,0.465953

... and a reminder a few minutes later...

Vibration Alarm,Attention please!

By the way, I set up the alarm when I moved it to take the following comparison shot, to show how small the device is.

P.S: it's about 17mm thick.

[ddlooping]

but can anyone else access it if they wanted to? say if a thief knew that there was one installed on a bike could they gain access to its where abouts?

Only a registered (what they call "SOS") number/phone can send messages or call the tracker.

what if your phone was stolen by a thief and they used the app....could they then find your bike or even track your movements?

The original idea was to use a phone but what I'm discussing now is the gizmo I've just received.

There is no app to install as it's not actually a phone, just a device that needs a sim card so as to be able to send SMS and relay audio.

To locate your bike, the thief would have to know what messages to send to the device. Possible but highly unlikely.

also what if some firm rings the phone (say ppi people) when its been nicked and you cant get through or the thief hears it ringing?

When you call the device from an SOS number/phone it will not ring, it's totally silent.

If you "ring" it for less than 10 seconds it will arm/disarm it's "parked/parking" (motion detector) function.

If you ring it for more than 10 seconds you will be able to hear whatever the device can hear around it.

The device uses both GPS and GPRS (not as precise) to geoposition itself, making it less likely not to be traceable.

I still have to test its reliability and durability (only time will tell) and lend it to a friend so he can stick it in his car to test for its accuracy.

[Paulwhite]

cool ....you should try it in a tin shed to see if you can get a signal as 9 times out of 10 if a bike is nicked it goes into a van then locked away somewhere.

[ddlooping]

Good idea, Paul, thanks.

[Paulwhite]

so how much has this tracker cost you? and do the company that you got it from have any legal obligations? like for example there not going to sell the info of you and you product/data to anyone.

im just trying to pick faults to see if there are any weekpoints/ risks of anyone using it against you. but it is a interesting idea that i might do for my bike.......the only thing thats racking my brains is that if its so cheep and easy to do then why havent all cars and bikes have them when they come out of the factory?

[ddlooping]

It costs me £35.99 but they have either bumped the price considerably or made a mistake when re-listing it.

http://www.ebay.co.u...8089#vi-content

Do the company that you got it from have any legal obligations?

...

If i'ts so cheap and easy to do then why havent all cars and bikes have them when they come out of the factory?

I have no idea.

[Cynic]

if its so cheep and easy to do then why havent all cars and bikes have them when they come out of the factory?

Lets look at this from another angle,

Car dealer, "Yes sir, insurance payout you say, last one was a ford. We do have some lovely offers"

or

Customer, "No i'm fine, was nicked but we got the car back very quickly thanks to the tracker. Not even damaged as the nicked the keys"

One option makes the firm thousands...........

Same as speed limits, the main thing that makes a sat nav the size it is is the screen for us dopey mammals to read it. It could easily be the size of a matchbox. Connected to the ecu it could tell the car just what the limit is. Then keep it there.

Would you buy that car? Not till its law, oh hang on that will never happen as if cars can't speed there will be no speeding fines. Same as the lights transmitting a signal to the car telling them they will change so you cannot jump them, easy enough technically, imagine the accidents that would save. Will they do it........?

Car telemetry has already been used to procecute, a Range Rover driver was procecuted for speeding and dangerous driving using the car's cpu for the speed and driving behaviour up to the accident. How the driver accellerated, braked steering etc were all in there as data.

[ddlooping]

P.S: the link to the item I've purchased...

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItemVersion&item=260973948089&view=all&tid=948758463016

[ddlooping]

Test 1: "in a metal box"

(I don't know what metal the box is made of)

The tracker received the SMS command and was able to text me its location.

Test 2: "in a metal box, in the oven"

Once again, the tracker received the SMS command and was able to text me its location.

So far so good.

Now I'm going to test its "Fence" function by sending it a message to set a 500m perimeter around my flat.

I should receive text alerts if and when the tracker goes out of this zone....

[ddlooping]

Test 2:

I tested the "Fence" function.

I went for a walk in town, with the tracker in my pocket, and it did send me a message (including lat/long) when I crossed the perimeter boundaries (set to 500m).

I then asked for my location while in a building (Barclays bank) and got a reply. It was however about 50 meters off.

I then did some more tests, while in the street and buildings but got no more replies!

I later switched the tracker off then on again and did some more tests.

They all worked, with a precision that I evaluate to be about 25 meters.

I think more testing needs to be done, and, more importantly, finding out why the tracker stopped working.

[ddlooping]

P.S: the precision might actually be better as I think Google Map was positioning the marker on the closest road.

[ddlooping]

I've kept on testing the device, while it's seating on my desk at home.

I get some discrepancies both using the "WHERE#" and "URL#": sometimes the location is close to a couple of meters to where the tracker actually is, sometimes it can be off by up to 25 meters in any direction.

Also, at times I only get 1 SMS reply, sometimes 2 or even 3.

From what I understand, it does this when it cannot lock to the satellites and send you the last known location. It then sends you another SMS as soon as it's able to lock on some satellites.

P.S: I feel like I'm talking to myself.

[Sacha]

I'm listening... I don't have any insight, and am a bit late on the thread, but better late than never right? It's been an interesting read.