Chemistry Reference
In-Depth Information
as a textile material. This includes criteria such as flexibility, water (laundry)
resistance, durability against deformation and radiation
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. Materials that
have the capacity of transforming signals into electric ones include:
•
thermocouple
: transforms thermal signal into electrical signals;
•
the soft-switch technology
: from mechanical (pressure) signals to elec-
trical signal;
•
fibre Bragg grating (FBG) sensors
: from mechanical signals over optical
to electrical signals.
Signals are transformed through a variety of methods:
•The soft-switch technology uses a so-called quantum tunneling com-
posite (QTC). This composite has a remarkable characteristic that
enables it to be an isolator in its normal condition and to change into a
metal-like conductor when pressure is being exercised on it
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•Fibre Bragg grating sensors are a type of optical sensor that has received
considerable attention in recent years. They are used for monitoring the
structural condition of fibre-reinforced composites, concrete construc-
tions or other construction materials.
•
FBG sensors look like normal optical fibres, but inside they contain dif-
fraction grid at a certain place that reflects the incident light at a certain
wavelength (principle of Bragg diffraction) in the direction where the
light is coming from. The value of this wavelength linearly relates to a
possible elongation or contraction of the fibre. In this way, the Bragg
sensor can function as a sensor for deformation
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8.5.3
Data processing
Data processing is one of the item components that needs attention only
when active processing is necessary. Textile sensors could provide a huge
amount of data, but many practical problems need to be overcome before
real computing fibres will be on the market
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.The problems include:
•
large variations of signals between patients;
•
complex analysis of stationary and time-dependent signals;
•
lack of objective standard values;
•
lack of understanding of complex interrelationships between
parameters.
Apart from this, the textile material itself does not have any computing
skills. Electronics are still necessary. However, they are available in minia-
turised and even in a flexible form. They can be embedded in water-proof
materials, but durability can be limited
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