Chemistry Reference
In-Depth Information
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Improved high-frequency shielding
: the fine fibres provide a very high
surface-to-volume ratio. Together with the excellent coverage, the
extra surface yields improved high-frequency electromagnetic interface-
shielding performance.
•
Reduced weight
: weight savings can be particularly important in
aerospace and similar applications where every milligram saved is
important.
•
Flexibility
: braid made from these fibres has successfully replaced
copper braid in military applications where freedom of movement and
durability are critical.
•
Compatibility
: yarns of conductive fibres are fully compatible with stan-
dard braiding equipment
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Battlefield acoustic sensors are required to detect, localise, track, and clas-
sify or identify targets of interest, which typically include vehicles, aircraft
and personnel
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More advanced electrotextile products such as thermal blankets for
human and animal use, computer keyboard and smart shirts to monitor
physiological conditions have appeared on the market in the past few years.
Researchers are conducting research and development in electrotextiles to
come up with a new generation of multi-functional and active 'smart tex-
tiles' that are able to harvest energy for self-powering, sense, response, and
adjustment to stimuli such as pressure, temperature and/or electrical charge.
Examples of large deployable structures featuring very thin, large flexible
circuits for use in space include synthetic aperture radar (SAR) antennae,
communications antenna reflectarrays, and active variable reflectance
solar sails.
In order to improve volume efficiency and reduce payload weight for
earth-orbital remote-sensing applications, low-mass membrane-based syn-
thetic aperture radar array concepts are being developed. One such system
is an inflatable deployable SAR consisting of thin fabrics or membranes
that are deployed for L-band operation with dual polarisation. The entire
assembly is flexible before employment and is rolled up onto the spacecraft
bus. The antenna comprises three membranes positioned vertically over one
another: the ground plane, the radiation patch, and the microstrip trans-
mission line membranes
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The increasing desire for localisation of soldiers on the battlefield
requires a new approach for their garments. This includes the implementa-
tion of communications systems through electrotextiles. Conductive fibres
are used in a conformal sensitive liner garment for the detection of wound
locations and medical sensor signal transmission for soldier health moni-
toring while on the battlefield. Textile-based antennae have already been
introduced in similar products, providing some key features including high
