How stressed are we? A sensor vest will soon be able to tell us. From
sports training to computer games, the garment registers the electrical
excitation of the muscles at any given time and determines the level of
Stressed out? Time to take a break? It will not be long before our
clothing gives us the answer. In the EU’s CONTEXT project,
companies and research institutes are developing a comfortable vest
that will read muscle tension and deduce stress levels at any given
time. At the core of the vest is “wearable electronics”.
This consists of sensors woven into the fabric that register the
electrical excitation of the muscle fibers, and thin conducting
metallic fibers that pass the signals to an electronic analysis system.
People’s muscle tension changes with their stress level –
the greater the stress, the more likely the muscles are to produce a
synchronous twitching effect. Though this is barely perceptible, the
electrodes register the change. The idea of the sensor vest originated
with biomedical scientists at the Catholic University of Leuven,
Belgium, who needed an inconspicuous measuring tool for stress studies.
Until then, they had affixed electrodes directly to their test
subjects’ chests. But this itself induced stress, with the result
that the tests delivered very little useful information. The new vest
is designed to ensure a more relaxed test environment. The project
members are exploring further potential applications such as a special
vest for computer games. By selectively tensing the torso muscles,
players could use the vest to control figures on the monitor and for
instance burst their heroes’ chains and fetters. The vest could
also contribute to safety at the workplace – perhaps ensuring
that workers do not lift loads that are too heavy for them. And sports
coaches could tell from the electronic vest whether athletes have
reached their performance limits or still possess energy reserves.
”The most important requirement for everyday use is a robust
electronic system,” says Torsten Linz of the Fraunhofer Institute
for Reliability and Microintegration IZM in Berlin, the partner
responsible for the “packaging”. The entire electronic
system has to be resistant to water and perspiration. The electric
conductors must not fray even after repeated laundry cycles, and the
sensors must be no larger than buttons to ensure that the garment is
comfortable. The IZM researchers have meanwhile developed stable
metallic fibers, watertight connections and durable sensor buttons.
Their task over the next few months will be to integrate the analysis
electronics. The project partners have already demonstrated during
field hockey training that the vest really works; it enabled players to
choose the ideal moment for striking the ball and to hit it much
further than usual.