Robotic sentries are making it a lot more difficult for terrorists, or any other hostile intruders, to launch attacks. One of the major problems with terrorists is that they can select their target and carefully plan an attack. Defense has always been very labor intensive, even with the use of video cameras. Someone has to watch the cameras to see if there is a real threat coming, and not just a stray dog. Same with line defenses (fences or motion detectors). Someone has to verify what has triggered the alarm. For decades, the solution to this was seen in pattern recognition software. That is, software that could look at the moving objects and identify them. Thats a tough job for software, and until recently, the pattern recognition software was not accurate enough to be really useful. But that has changed. Partly thats because decades of software development has solved a lot of fundamental problems, and the sensors have gotten more sensitive, and cheaper. So now an Israeli firm, Controp, has developed software that can use high resolution vidcams during the day, and thermal imaging cameras at night, to spot, and identify anything moving within several kilometers of stationary, or moving (in aircraft, ships or ground vehicles) cameras. When something matches the profile (human or vehicle, or even a small boat in the surf), an alarm goes off, calling the human operator to confirm what is out there and take action. Isolated bases in Afghanistan and Iraq are using this technology, as are many other valuable installations (including the Olympics in Greece last Summer.) The systems are relatively cheap (about $250,000 per site, depending on the number of cameras used.)

Whats particularly useful about these new systems are how effective they are at night, and against targets in rough water. Even the human eye has a hard time spotting a small boat approaching in rough seas. But the Controp software can make out an inflatable boat full of explosives approaching an anchored warship at night. Ground forces find it useful for patrolling wide open areas at night. Even with night vision devices, it tires out a hummer full of troops in a few hours of patrolling, with everyone straining to see if anyone is out there. But the Controp software does all the searching with several FLIR (heat sensing) cameras, leaving the troops rested and ready for any hostile encounter. 

The Controp system borrows from nature. Predators, be they hawks and other raptors, first detect motion, then zero in what is moving to identify it. A weed moving in the wind is ignored, a small mammal is quickly identified and becomes a meal. The Controp software is very effective at ignoring harmless moving objects, while alerting the human operator when something more sinister is spotted. The system has undergone a lot of testing by intruder teams that test the security of high value installations. In addition, there has been even more actual use in combat zones, where no one has yet come up with methods to fool the software. Thats not for lack of trying, which is why the pattern recognition software continues to be refined.