Combating Terrorism Technical Support Office (cttso), an agency of the defence department, has now developed a system, dubbed Jetson, is able to measure, from up to 200 metres away, the minute vibrations induced in clothing by someone’s heartbeat. Since hearts differ in both shape and contraction pattern, the details of heartbeats differ, too. The effect of this on the fabric of garments produces what Ideal Innovations, a firm involved in the Jetson project, calls a “heartprint”—a pattern reckoned sufficiently distinctive to confirm someone’s identity.
To measure heartprints remotely Jetson employs gadgets called laser vibrometers. These work by detecting minute variations in a laser beam that has been reflected off an object of interest. They have been used for decades to study things like bridges, aircraft bodies, warship cannons and wind turbines—searching for otherwise-invisible cracks, air pockets and other dangerous defects in materials. However, only in the past five years or so has laser vibrometry become good enough to distinguish the vibrations induced in fabric by heartprints.
A spokeswoman for the cttso, soc has now received its first batch of Jetson heartprint readers. According to her revelations ,the beam involved is infrared, and therefore invisible to the human eye. The devices work best, she says, when a suspect is neither running nor in a moving vehicle. And they have a gimbal that helps keep the beam focused on the suspect for the 30 or so seconds it takes to obtain a good heartprint reading. She will not, however, discuss the process by which heartprint libraries might be built up in the first place. One starting point, presumably, would be to catalogue the heartbeats of detainees in the way that fingerprints and dna samples are now taken routinely.
Confirming the identity of enemy targets is not the only job imaginable for this high-precision form of laser vibrometry.It has potential medical uses, too. Brimrose hopes to run a clinical trial employing it for the detection of arrhythmia and other heart problems.
A team at the State University of New York, Buffalo, is designing a device that emits radio waves and captures return signals that have bounced off, and been modified by, a person’s vibrating chest cavity. The advantage of this approach is that it can penetrate materials opaque to light waves, such as walls and heavy clothing.
Governments could employ the technology to identify masked protesters.But could be stymied by protesters wrapping their torsos in tinfoil a version of the tinfoil hats allegedly loved by those paranoid about government snooping.