No matter how hard you try car thieves always figure out a way to circumvent your alarm system. But pretty soon, talking cars will hopefully prevent the lost of your fav wheels. A system called SVATS (Sensor-network-based Vehicle Anti-theft System) has been designed by Hui Song from Frostburg State University, Maryland, US, in collaboration with colleagues at Pennsylvania State University. In the system cars loaded with sensors keep communicating with each other and in case one of them is being swiped, the other will raise the alarm in a matter of seconds. This is how it works:

The system starts when the driver of the vehicle switches on the transmitters fitted inside using a remote control, at the time of leaving the car. Then the car sends out a "join" message to all the nearby cars. The cars chooses its nearest neighbors to act as its sentinels and prefers partners that need the lowest signal strength for communication, so that the system does not consume less of the car's battery. The car continues sending out periodic "alive" signals to these watchers, till the time the owner returns and it finally sends a "goodbye" message. In case the "alive" messages stops abruptly without the customary "goodbye" message, then the cars acting as "watchers" immediately sound a theft by transmitting a message to a central base station. This in turn triggers the alarm, which then notifies the security guard of the car park, the owners of the vehicle, or the police.
The system is so tight, that in case it senses a car moving unexpectedly, it measures the signal strength of any "alive" messages. And if that happens, it transmits a warning message to other cars that are keeping a check on the same vehicle, because it is likely to be moving. Apparently the theft alarm message will only be sent to the base station if a watching car gets more than three such warning signals from different sources.

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