Israeli jails are using a custom-built computer program to interpret the barks of guard dogs and distinguish warnings of a breakout from everyday woofs, a prisons official said Monday.
Noam Tavor, head of the Israel Prisons Service canine unit, said the program is designed to overcome mistakes in which guards have either not heard dogs sounding an alarm or failed to speedily identify its significance.
"It collects the dogs' barks through microphones ... and sorts and grades them," Tavor told Army Radio. "It relays only the barks that are significant in terms of security — barks that reveal stress or aggression in the dog."
The radio said prison staff monitor the system through loudspeakers and TV cameras that automatically zoom in on suspected hot spots.
Because of their heightened sense of smell and hearing, dogs can identify suspicious people well before they trip an alarm wire, Tavor told The Associated Press Monday.
The Prison Service has long used dogs to patrol its fences, but found the system had flaws. "The dogs would bark, and staff of the prison wouldn't hear it, or would hear it and would not take action fast enough." Tavor said.
He said prison staff would also sometimes ignore dogs' barks if they thought it was nothing serious, what he called the "boy who cried wolf" phenomenon.
Six years ago, the Prisons Service joined with Bio-Sense, a high-tech company headquartered near Tel Aviv, to create a system that would notify them when dogs were barking because of something suspicious.
Bio-Sense recorded the patrol dogs barking in different situations, from playtime to cat encounters to real emergencies. They loaded thousands of these recordings into a computer program to determine "what makes the emergency bark different than the other barks," said Bio-Sense project manager Orit Netz.
One of the keys turned out to be the dog's stress level.
Bio-Sense developed a sensor that can determine a dog's stress based on the sound of its bark. The sensor can be placed within a 15 yard radius of the dog to detect the "emergency barks" and sound an alarm in the prison's control room.
According to Bio-Sense, they are the only ones to have developed this technology. "We don't have any competitors at the moment," Netz said.
The first system was put in place in 2005, and since then three more have been installed in Israeli prisons. Bio-Sense now has more than 100 clients in Israel, including farmers who need protection against theft, Netz said.