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Tracking a stolen cam: new technology

Posted: Sat Apr 06, 2013 10:10 pm
by RR_Security
I don't know when this system might be available. The concept was proven in 2010 or earlier, and I just recently found out about it while reading an article in the 12/2010 issue of POLICE magazine. I must have skipped the article when I first got that issue in the mail, because I think this would have gotten my attention:
New research at The University of Memphis gives rise to new technology that largely defeats the battery/power problem. AutoWitness is a penny-sized device intended for concealment inside theft-prone items like computers. A motion-detecting accelerometer, gyroscope, and vibration sensors on the AutoWitness determine when the object is being moved, and whether the movement is characteristic of everyday activities or something new, indicating theft. The sensors also pick up on direction of movement, serving as a kind of dead reckoning positioning system.

The movements are logged internally until a pre-programmed interval has passed (so as to avoid detection) and the AutoWitness senses that there is a sufficiently strong cellular network or other RF signal suitable for transmitting its data. It works best when it is surrounded by a dedicated network of base stations intended to detect the devices and receive their transmissions. However, location detection is about 90 percent accurate when the only localization data is from cell towers. When it comes time to find the specific location of the item carrying the AutoWitness, a dedicated handheld receiver can interrogate and locate the device.

AutoWitness has the potential for some interesting moving surveillance applications. One of the most attractive aspects of this technology (which is truly remarkable and far too complex for me to address here) is that the finished product is expected to cost only $10-$20 per unit.
:o
Here is a link to an article about AutoWitness: Kumar's anti-theft sensor steals the show.
For those who really want to read about the science involved, look here: AutoWitness: locating and tracking stolen property while tolerating GPS and radio outages. The PDF is a research paper presented at the ACM (Association for Computing Machinery) Conference on Embedded Networked Sensor Systems (SenSys 2010) in Zurich, Switzerland. I read a few pages of it last week, but finally printed it this afternoon so I can see how much of it I actually understand. (I might just skip over things like "The algorithm uses a Hidden Markov Model of city streets and Viterbi decoding to estimate the most likely path." Image)

This afternoon, I emailed Dr. Kumar, and received a very quick reply inviting me to call sometime next week and discuss some questions (and maybe some ideas) I have. If anyone here has questions, let me know so I can add them to my list.

Re: Tracking a stolen cam: new technology

Posted: Sun Apr 07, 2013 8:17 am
by Chachoze
Assuming that your intention is to use them in trailcams i cant see them being very usefull as I doubt there would be many nodes out in the country for the foreseeable future and would only work if the perp passed it through a metro area that might have nodes..perhaps to sell it or something because it sounds like it doesnt communicate through cell netwrks directly.

Re: Tracking a stolen cam: new technology

Posted: Sun Apr 07, 2013 9:37 am
by tbone303
any idea if this would be an expensive feature or not :?:

Re: Tracking a stolen cam: new technology

Posted: Sun Apr 07, 2013 11:07 am
by robnj
lots of thieves are going to get a surprise when the police are knocking on there door.

Re: Tracking a stolen cam: new technology

Posted: Sun Apr 07, 2013 11:39 am
by RR_Security
Assuming that your intention is to use them in trailcams i cant see them being very usefull as I doubt there would be many nodes out in the country for the foreseeable future and would only work if the perp passed it through a metro area that might have nodes..perhaps to sell it or something because it sounds like it doesnt communicate through cell netwrks directly.
I'll ask about that. Reading the "killer math" literature, I got the impression that the nodes ("anchors") would help with tracking, but wouldn't be absolutely necessary.
Besides trail cams, there could be a lot of different uses for the system, so hopefully more and more nodes will be installed as overall demand grows. I've already got a ideas for a bunch of places I'd hide one of those sensors, stuff we never thought of as a target for theft until it "grew legs" one day.

any idea if this would be an expensive feature or not :?:
"Expensive" might be a matter of individual opinion. In the articles, it says they hope "a tag [sensor] price in the tens of dollars will soon be viable at volume." (Meaning that enough people buy sensors for TVs, computers, and all the other things that aren't trail cams.)
They used rechargeable batteries for the experiments, but were planning on using primary batteries for sensors in the field because of lower leakage currents. The idea was that the whole sensor would be replaced when the battery got low, but I'll ask if it would be possible for users to send a sensor in for "recycling," or if maybe rechargeables could be used in specific applications like trail cams.
I don't know if there would be any ongoing costs like monitoring charges, etc., but I don't think there are. The user buys the tag and installs it, and that should be all except for maintaining the battery.

lots of thieves are going to get a surprise when the police are knocking on there door.
Man, I hope so. I can foresee a new show on TruTV, "The Smoking Gun Presents: World's Most Surprised Criminals." :twisted:

Thanks for the input, guys. 8)

Re: Tracking a stolen cam: new technology

Posted: Tue Apr 09, 2013 3:14 pm
by RR_Security
I just had a nice phone conversation with Dr. Kumar at the University of Memphis. Here's an update, with some more information.
I wasn't writing anything down, so before I forget too much of it:
1) Rechargeable batteries in the "tags" are a possibility, or the tags might be "recyclable" if the user can't replace the primary battery themselves. (I mentioned that some trail cam owners use solar chargers for their cams.)
2) The "anchor nodes" along roadways won't be required.
3) Even if the tag can't get a cell signal for awhile, it will store information about its path and location until it detects a cell connection. Then it can send a "I've been here, here, and here" message. (I forgot to ask how the location(s) is/are determined; whether it's GPS or some other method.)
4) Besides GSM, the tags will use something called ZigBee. <http://en.wikipedia.org/wiki/ZigBee> I think that will be the way a tag communicates with the user's cell phone. (So you can use your passcode to disable a tag while you're working on the cam, moving your $1.2M Stradivarius around inside the house, etc.) It's also how police mobile or handheld trackers would "ping" the tag in a stolen article. (All tags will have an individual ID.)

Dr. Kumar was going to conference another one of the researchers onto our call, but was unable to do so. I forgot the name, but that person will be making the decision about what company is licensed to produce the tags. That decision will be the big step towards getting AutoWitness into the hands of end users.

There's still a lot I don't completely understand about AW, but I think it has a lot of potential.

Re: Tracking a stolen cam: new technology

Posted: Tue Apr 09, 2013 7:59 pm
by Chachoze
So those tags really do communicate with cellullar netwoks? I thought it was just through those nodes and some kind of local comm through a cellphone... I guess I missed that part. If thats the case then this would answer a lot of trailcam owners prayers when it comes to stolen cams.

Re: Tracking a stolen cam: new technology

Posted: Tue Apr 09, 2013 10:49 pm
by RR_Security
So those tags really do communicate with cellullar netwoks? I thought it was just through those nodes and some kind of local comm through a cellphone... I guess I missed that part.
I think that might have been one early idea, with the "anchor nodes" acting kind of like an E-ZPass system. I can't find any mention of them in the paper presented at the ACM SenSys conference; only in a couple of news articles, and Dr. Kumar said those were incorrect.
I forgot to ask him if the tags use a SIM; I haven't seen that mentioned so far in any of the literature.
I also meant to ask him about GPS on the tags, but somehow skipped over that question. I was thinking "geofencing" might allow an authorized user to change batteries and memory on a cam without causing false alarms, but if the tag (cam) went outside certain boundaries, then the alerts would start. I assume GPS might provide better locates in areas like where I am, with GSM towers few and far between. When I used to work in a forest fire lookout, we could get a good (horizontal) azimuth with the Osborne Fire Finder, but it really needed an intersecting azimuth from another lookout tower to figure the distance from each lookout. The more lookouts that could get a bearing on a smoke, the more accurate it could be pinpointed on the map. I don't know if that's how cellular locating works, but my guess would be that it does.

If thats the case then this would answer a lot of trailcam owners prayers when it comes to stolen cams.
That's what I was thinking. Another reason I wish AT&T and/or T-Mobile would get some more towers in service.

In addition to cams, I've already got a whole list of things I'd like to hang a tag on, and then just wait for some thievin' bastitch to steal something.
"Hello, Light-fingered Louie. It appears you have something of ours. We're here to get it back. Your ride to your new accommodations is the car with the lights on it." Image :twisted: