Wednesday, January 26, 2011 at 7:13PM
A research group out of USC offers some impressive results on a smart fence system. The system uses three different types of sensors for protecting remote fenced or virtual perimeters. They are:
a) acoustic based long range sensor with which vehicles' engine sound and type can be identified
b) vibration based seismic analyzer which discriminates between human footsteps and other seismic events such as those caused by animals, and
c) fence breaching vibration sensor which can detect intentional disturbances on the fence and discriminate between climb, kick, rattle, and lean.
For example, the fence system distinguishes between someone climbing the fence (it sends an alert) versus someone kicking the fence (it ignores the disturbance).
The fence performs very well. According to the leader of the project, Alireza Dibazar, the system showed "a perfect (100%) identification of unexpected intrusion events, and an average of less than two false positives per week and zero false negatives for recognition of human footsteps. In addition, no false positives or false negatives were reported by the installed fence sensors for a duration of 45 days of unattended operation, which included several days of seasonal storms."
More information can be found in their paper: Intelligent acoustic and vibration recognition/alert systems for security breaching detection, close proximity danger identification, and perimeter protection