A matrix of piezoelectric sensors that can be woven into garments
is finding new applications in the testing of body armor, shoes, orthotics, athletic
gear, mattresses, consumer clothing lines and industrial equipment.
Known as Tactilus Body Mapping
Technology, the system is significant because it can incorporate hundreds
of sensors in a flexible, multiplexed fashion, enabling researchers to monitor
pressure points all around a body. It's being used by the U.S. Air Force, Philadelphia University and KDH Defense Systems to map
pressures caused by body armor, and by the U.S. Army to study how body armor
affects soldiers in the field. Sensor
Products Inc., maker of the technology, says that the integrated nature of
the system enables engineers to obtain results they might not otherwise get.
"If you did
this simply by building single sensors and scattering them around the garment,
you'd get very localized results," says Jason Blume, electronics project
manager for Sensor Products. "But with our method, you're covering the whole
area. Areas that would not otherwise be monitored are now getting monitored.
You couldn't do this with a conventional instrumentation approach."
In the U.S.
Air Force project, researchers are using the system to identify pressure points
that develop, not only when soldiers stand in place, but when they perform
ballistic motions, such as jumping, running, turning, crouching or crawling on
their stomachs. Design engineers are employing the data gleaned from the
project to develop new vests and body armor systems that optimally distribute
the load that soldiers carry.
Tactilus system consists of four major components: piezoelectric sensors;
analog-to-digital converters; a multiplexer and software. Multiplexed data from
the sensors is converted to digital signals and then processed by laptop-based
software. One sensor matrix can contain as many as 1,024 sensors.
Blume says the technology has been used in industrial
design applications, such as lamination presses and heat seals. It's also been
employed in the design of orthotics in shoes, as well as in the design of consumer
clothing. Makers of athletic gear have similarly used the technology to
quantify fit in compression-fitted clothing.
measurements without interrupting what someone is doing, you have to have a
system like this," Blume says. "There are other ways to do it, but they're not