Diy Gps Car Tracking (auto-arming)

[lee81]

Hi,

For the last few months I've been working on a low cost DIY GPS Tracking solution. I'm at the stage where I have it working in my own car, though there are a few issues I still need to address (surrounding ease of use).

In summary, for around $150 (*using some second hand components) and $20/year, you can have a satellite GPS tracking solution, that will automatically ping your mobile phone when your car starts moving, and will reply with GPS co-ordinates when you send a request through via SMS (if want to manually request position).

A more detailed rundown is as follows:

- A mobile phone and bluetooth GPS receiver are installed covertly in car (wired to battery power).

- The mobile phone has a java application on it that continously polls the GPS receiver, and processes the result to determine whether the position has changed (among other things)

- In a typical scenario, the first GPS fix that comes through becomes the 'armed' position, as soon as the current GPS position moves > a threshold distance from the armed position, the car is known to be on the move, and an alert is posted

- Before sending the alert to your own mobile phone (as an SMS containing GPS co-ordinates), it tests whether a predetermined bluetooth device can be detected. This bluetooth device should be set to be your own mobile phone (but could be another device). If the tracker detects your 'disarm device' in this manner, it can discard the alert - effectively when your mobile phone is in range of the car, it disables the tracker alerts from being sent. If the disarm device is not detected, then an SMS is sent out with co-ordinate information (on a predefined interval, every 8 minutes for example). This kind of auto-arming can give the user peace of mind (you can never accidentally forget to arm).

- Optionally you can send an SMS to the tracker with your own mobile, requesting a position reply, where it will SMS you back the latest GPS fix data. Unfortunately you need to use a special java application to send these SMS requests to the tracker, as the SMS must be sent on a special port (eg. this cannot be done using your normal SMS sending interface).

Issues / considerations

- You must have a bluetooth device available in order to use the auto-arming (alternatively can send an arm / disarm request via SMS), which is always in discoverable mode. Only some mobile phones remain in discoverable mode (as it's not ideal for phone security). If your mobile doesn't remain in discoverable mode, it cannot be detected by the tracker. I'm still looking for better arming options than this (a cheap bluetooth device that remains in discoverable mode, that you can plug into car power to activate when you get in car, would be nice). My own mobile phone doesn't remain in discoverable mode (by default), I've had to write software to force it to stay in discoverable mode.. There are ways to detect a phone not in discoverable mode (attempt to open connection to a known bluetooth device, for example) - unfortunately there are stability issues when trying to disconnect GPS in order to connect to phone, when done repeatedly - eventually the GPS receiver I've been using will stop working. You cannot have two bluetooth connections open at a time (on any cheap phones I've seen), so this is not an option (keeping GPS connection open, *and* attempting to open connection on the disarm bluetooth device).

- You need a mobile phone SIM for the mobile phone installed in the car. iSim (by Optus) has the cheapest prepaid plan I could find, shouldn't cost more than $20 annually ($10 min recharge with 6 month expiry).

- Right now the java software I've written has a lot of fixed settings, so I need to compile a new app if want to change various settings. As time goes on this will become user configurable (without me having to compile new versions).

- A mobile phone will not allow java software running on it to automatically send an SMS, you will find it will prompt the user "do you want to allow the program to send etc", which prevents the alert from being sent. There are good reasons for this (to prevent dodgy software from automatically SMS'ing numbers). To overcome this you need to do a special installation on the phone to bypass the security - it's easy to do, but I only know how to do it for motorola phones.

- GPS devices work best in open sky, the signal degrades as things get in the way between it and the tracking satellites (this includes car roof etc). The latest SirfIII GPS chipset is sensitive enough to work indoors, can't comment on other chipsets. You may have to take steps to keep GPS tracker (size of matchbox) from being under too many layers of metal etc.

- If you cut the power supply (charger) to the GPS receiver, it will automatically switch to internal battery power (which can last for days). However there is a bug in the BT-338 receiver, which means it will automatically shut down within 10 minutes, even if power is restored . So I'm on the lookout for a better model without this problem, no doubt there is a different model that doesn't have this problem, but it's *probably* not an issue, in general.

Costs

- Bluetooth GPS Tracking device, $60-$80 new off ebay (prefer SirfIII chipset). Have used GlobalSat BT-338 GPS receiver.

- Mobile phone supporting bluetooth API (JSR-82). I've used a motorola L6, as it's the cheapest phone I can find with this API. I wouldn't count on the java tracking software working on other phones (couldn't say until I tried), so to be on the safe side, need to stick to this exact model. Prices range from $120 (new) to $50 (used), easily found on ebay. If you're really on a budget can use the damaged phones (speaker/mic not working), can pick these up for around $20 off ebay if you're lucky enough to come across one .

- SIM card, suggest iSim.com.au, costs $20, then $10 recharge every 6 months

Anyway I've had this system live in my car for about a month now (initial trials), and has been working great. I've got mild concerns that after extended periods the java application on the phone will crash (after months of operation), but this is yet to be determined, in theory it should be fine. I'm looking for people interested in getting this set up in their own car, guinea cops, if you will . Seriously though, it does work, and it's pretty cheap solution for this kind of technology. The fact commercial GPS tracking solutions charge $300+ anually for monitoring is utter rubbish, when it can be done automatically (I'm still at a loss as to why there is a monitoring fee..).

I'm willing to provide all software (free of course) and help people get it set up (if they have any complications, questions), but I can't promise to be upgrading software with new features / to support different phone models - depends on if I have time, and if I can be arsed. You'll need to do all the leg work finding the appropriate hardware as described above (strongly recommend ebay for this). Any comments, suggestions are welcome (encouraged). Also if you know of any equivalent systems let me know, as this is the reason I developed it, as I couldn't find something that could provide this functionality.

If you're interested in setting this up in your car, PM me. This is new software, so please don't expect it to be bulletproof - it's still in prototype phase. I've not had any issues so far, but I don't want people to stake their car security on it functioning as described , so best at this stage as an additional layer of security / hobby project etc. For anyone who doesn't know, the GPS receiver will pin your location down to around 10 metre accuracy.

Cheers

[Chris Rogers]

location - can you geofence?

[MBS206]

There's a system like this out at the moment.

And it's also an immobiliser/alarm.

You can SMS it to immobilise or lock the car.

Get position via SMS of the car, or jump on the net, and view a map of where the car is.

The downside, the system is around $1000 (But, it's also an integrated alarm/immobiliser) and you can remotely check status of the car, and arm/disarm features.

So full alarm+immobiliser, with tracking...

Can't remember name atm... :S

Also, pre paid isn't recommend by alot of people, as you need to keep getting access to the phone to recharge it (Or some you can call up and do it with an operator) but again, plan is easier, as you know it won't run out of credit.

[lee81]

location - can you geofence?

First time I've heard of geofencing, but having looked it up.. no it doesn't support geofencing . Not that it looks like it'd be hard to integrate, just as it stands the functionality is really basic - car moves, owner not in proximity of car, send SMS (little more complex than this, but that's what it boils down to).

[lee81]

There's a system like this out at the moment.

And it's also an immobiliser/alarm.

You can SMS it to immobilise or lock the car.

Get position via SMS of the car, or jump on the net, and view a map of where the car is.

The downside, the system is around $1000 (But, it's also an integrated alarm/immobiliser) and you can remotely check status of the car, and arm/disarm features.

So full alarm+immobiliser, with tracking...

Can't remember name atm... :S

If it didn't have ongoing monitoring costs (when you're not using it, I mean), that would be pretty cool, I couldn't find anything free of (or with low) subscription costs when I looked (definitely may have missed some). For me this was very important, I wouldn't be happy with high annual fees. Part of this is because my car just isn't worth enough to justify high ongoing security costs - at around $12k, even the $1k once off expense on security is a bit difficult to justify for someone like me (*cough* tightarse) . Honestly I think around $400-600 for hardware and $50/annum would be around my comfort zone, and if I'd found such a package, I would have run with it.

Also, pre paid isn't recommend by alot of people, as you need to keep getting access to the phone to recharge it (Or some you can call up and do it with an operator) but again, plan is easier, as you know it won't run out of credit.

Agreed it's a royal pain to pull the phone out, and I didn't want to have to do this. As it is the recharge is $10 automatic recharge when credit level drops below $10, so not a problem - though this could be an issue for other prepaid plans. I dont' know of any competitive non-prepaid plans (that would cost anywhere near $20/year), but if anyone knows of any, please post the details.

[Dan_J]

sorry i just red until da 2nd paragraph, but wont ur bluetooh go out of range at sum point?

Edited December 24, 2007 by Dan_J

[lee81]

sorry i just red until da 2nd paragraph, but wont ur bluetooh go out of range at sum point?

There are two mobile phones, one is installed in the car, and communicates with the bluetooth GPS receiver. The mobile installed in the car also attempts to detect if the users personal mobile phone is in range (scanning for bluetooth presence), so it's when this bluetooth link from mobile to mobile goes out of range, it knows the owner is no longer in or around the car - so if the car starts moving, it's being moved without authorization and the owner will be notified.

[Vija]

Hi, thanks for doing the hard work...I'd be keen to try it Do you have any idea of a better bluetooth gps to try that doesnt turn itself off after the power loss? Also, what power feed are you giving the gps and mobile? I assume car charger for the phone but the gps says it needs 5V?

[lee81]

Hi, thanks for doing the hard work...I'd be keen to try it Do you have any idea of a better bluetooth gps to try that doesnt turn itself off after the power loss?

I've asked the question on a GPS forum (which GPS wouldn't suffer from this shutdown problem), but never got any feedback . There's definitely a model out there that doesn't have auto-shutdown, I believe it has a toggle on/off switch (so remains either on or off), but it's slightly more expensive, and I don't know about the sensitivity. I have my doubts about the most recent GlobalSat model as well, I suspect it would have the same issue, GlobalSat haven't replied to my enquiry about the problem . It's going to be a case of trial and error, when I set it up for a mate I'll use a different model, and see if it's any different.. It's happening because of the 10 minute auto-shutdown when no bluetooth active (power saving), it's just bugged because it's not detecting the bluetooth connection as active if you establish bluetooth connection *before* fixed power is cut. If you connect to GPS after power is cut, it won't shut down (until battery runs out).

Also, what power feed are you giving the gps and mobile? I assume car charger for the phone but the gps says it needs 5V?

Car charger for the GPS, the BT-338 unit comes with the car charger. Phone as you mentioned uses its own car charger. I think it's 5V as you've stated, definitely don't wire 12V directly to either device .

[jarthel]

has anyone else tried this solution with much success? thank you

[Trav33]

I'd be interested in an update from you Lee, to see how you've got on with this project.

Have you looked into taking it to the next stage, and programming a PIC/microcontroller to interface to a gsm module and gps device.

[lee81]

Well I've had the opportunity for a lot of testing since my earlier posts, unfortunately the testing cycle is long. It takes several weeks to test stability fixes, as that's how long it takes for stability issues to crop up. I suspect they are hardware related (I don't think mobile phone java applications were designed to run for weeks/months on end). It's my intention to post the software on the forum at the point I've had it running for several months uninterrupted, but still getting to that point.

Right now there is just one issue remaining. After about a week or more, the phone stops receiving data from the GPS unit. There is nothing to indicate a problem has occurred, it's just as if the GPS unit stops sending out information. When the tracker application detects no new data is coming from the GPS, it now sends a message telling you it's offline (so you will always know it's stopped working). At this point you can manually go and restart phone and GPS unit, to get it working again (obviously tedious, and needs to be fixed). If data stops coming through, the most obvious workaround is to disconnect and reconnect from within the tracker software, but this doesn't work (it's as though the phone or GPS bluetooth hardware has locked up, requiring a hard reset).

Note GPS comms offline is not to be confused with GPS being unable to get satellite fix. If the GPS unit is under cover (unable to get a position from satellites), it still transmits bluetooth data to phone; you won't get 'offline' notifications just because GPS unit is in an undercover carpark etc (which is normal), only if GPS unit stops communicating altogether.

I've had it running continuously for just over a month in my car, without this problem showing up. However I left my car for two weeks without giving it a drive, and the car battery went flat - so I'm not sure how long it would have gone for. Someone running the same version of software reported the issue within a week or two, so there's still some fixes required. It might be a case of trying different hardware (phone and/or GPS unit), but I haven't got around to that stage yet. If the software revision I just finished still exhibits the bluetooth connection dropout, I'll start testing with different hardware to confirm whether or not that's the problem (out of ideas from the software side).

Some other notes:

- Have observed 'bad' GPS readings coming through (suspect a single corrupt reading comes through, in between good data). Not sure if software or hardware, but latest software performs filtering to prevent these bad readings from raising false alarms.

- Regularly leave car for a week without driving, and car battery remains OK with tracker installed. Took somewhere between 8-12 days to drain my car battery dead flat - so power consumption of phone and GPS unit is moderate.

- I mentioned in my first post the BT-338 turns off after 10 minutes once external power disconnected, even if external power is then reconnected. Need to clarify it only turns off if external power remains disconnected (if you reconnect external power it will stay on). Will be testing shortly with Holux M-1000, which has a slide (on/off) power switch; shouldn't have any auto-shutdown issues with this model.

To answer your question Trav, I haven't looked into any hardware programming (PIC/microcontroller). By removing the need for the bluetooth between phone and GPS, it would save on hardware costs, power usage, and improve stability - but this kind of thing is beyond my abilities .

[Savman]

WOW how badly i wish this was in my car now. I was looking into this before my car was stolen, to late now. Please people get this installed and when you find them send there adress to me...

[Richieb]

Already done and workin. I hope someone makes my day.... hehe, no care what the repercussions are, the steel shot will stop em for sure...!!

What was it before some scroat got his sticky fingers on it, post the details so we can keep the SAU eye occupied.

Look here for info http://www.traceamobile.com/

Ooops, here - http://www.locatemyphone.com.au/Pricing.aspx

Edited April 10, 2008 by Richieb

[Chris Rogers]

OR

www.ezy2c.com

that gives you a map to follow it on and what is happening INSIDE teh car at anygive time including speed.

[lee81]

OR

www.ezy2c.com

that gives you a map to follow it on and what is happening INSIDE teh car at anygive time including speed.

What are the costs involved with the ezy2c? I couldn't find any prices, but it looks to be pretty close to what I've been trying to achieve. If the geo-fencing is automatic (i.e. fixed radius about the area it was armed), it would be great if the price is right. There are a bunch of new products coming to the market, but they all seem to have in common high ongoing fees . I would be fine with forking out $400-$500 for a tracker unit *if* I didn't have to fork out for a so called 'monitoring' fee.

[Chris Rogers]

its a bit more than that on the retail side. it does have a monitoring fee as well but not $3-400/yr. the whole lot is web based and trackable over a period of time (IE hours/days/months.) and can export into a excel sheet.

I have one already and I use it for time tracking on my van.

questions ask

[Rekin]

Already done and workin. I hope someone makes my day.... hehe, no care what the repercussions are, the steel shot will stop em for sure...!!

What was it before some scroat got his sticky fingers on it, post the details so we can keep the SAU eye occupied.

Look here for info http://www.traceamobile.com/

Ooops, here - http://www.locatemyphone.com.au/Pricing.aspx

thanks for the locatemyphone link. Sounds really interesting

[lee81]

Well after a long 8 months of testing, I believe I've finally ironed out all the bugs. I've also added a pretty cool feature, viewing real time tracking data over google maps. I also found that exetel has a postpaid mobile SIM plan with no ongoing costs (same plan has cheap pay on demand GPRS internet). This means you can have GPS tracking in your car with *no* annual fees whatsoever, you only pay when you actively request the location, or the car is sending you alerts .

Attached is the zip file containing everything you need to get up and running. Also contains a detailed user guide, which details all features and how to use them.

New features include:

- View location of your car in real time, using google maps. Only cost incurred is cost of GPRS data usage, for data sent from mobile phone to your computer (which is minimal, just a few hundred bytes per minute). You can test this feature using emulation mode, to preview how it works.

- Battery low warning sent via SMS

- Most parameters configurable (such as 'stolen' alert distance thresholds, battery warning levels)

Now I need to mention that soak tests (running for prolonged periods of time) are ongoing. So as noted in the documentation, I haven't tested as much as I'd like. There is a chance bugs exist in the hardware I've recommended that will cause the tracker to drop out after a few months. I can fix software bugs, but not hardware bugs.. At worst, it means the tracker will go offline, but it will send you an SMS letting you know it's no longer active - you then need to manually power cycle the GPS unit to get it running again.

I've been running the tracker continously since 30-July, so that's 8 weeks of continous operation - I'm hopeful it will continue running this way indefinitely.

Any questions let me know!

Cheers

gps_tracker_240808.zip

[Trav33]

Sounds like you've put a lot of hard work into it. Its unfortunate that you're only able to work with a very specific phone and GPS combination, and not a generic Nokia for example (I read your reasons why though).

Is there anything else your device can do, which can't be done on the GPS GSM unit available on the SAU GroupBuys section and EBay for around $280? This may be an easier option for others, which wont cost much more by the time you get all your different components together.

http://www.skylinesaustralia.com/forums/Re...Ca-t200630.html

Well done on what you've built though!