Abstract:
In construction, smart materials and systems could be used in 'smart'
buildings, for environmental control, security and structural health monitoring
e.g. strain measurement
in bridges using embedded fibre optic sensors that can feel pain with fiber optic
nerve systems.
Magneto-rheological fluids have been used to damp cable-stayed bridges
and reduce the effects of earthquakes. In
aerospace, smart materials could find applications in 'smart wings', health and
usage monitoring systems (HUMS), and active vibration control in helicopter blades.
In marine and rail transport, possibilities include strain monitoring using embedded
fibre optic sensors.
Smart textiles are also
finding applications in sportswear that could
be developed for everyday wear and for health
and safety purposes.applications in telematics and traffic management Structural health
monitoring, control and lifetime extension (including self-repair) of structures
operating in hostile environments, e.g. vibration
control in Aerospace and Construction
applications. Thermal management of high temperature turbines for power
generation. Selfmonitoring, self-repairing, low maintenance structures, e.g. bridges
and rail track Smart structures that can self-monitor internal stresses, strains,
creep, corrosion and wear would deliver significant benefits.
A. Structural Health Monitoring
Virtual human robots can be equipped with sensors, memory, perception,
and behavioral motor. This eventually makes these virtual human robots to act or
react to events.
* Also called Damage Detection
* Using response signals to determine if there has been a change in
the system's parameters.
* Mathematically very much like parameter identification in many respects
* Numerous methods have been proposed.
* Impact is high for SMH systems that work without taking the base
system out of operation.
B. Smart Structures
Key areas of focus for the development of smart structures to include:
Miniaturisation and integration of components, e.g. application of sensors or smart
materials in components Robustness of the smart system, e.g.interfacial issues relating
to external connections to smart structures Device fabrication and manufacturability,
e.g. Electrorheological fluids in active suspension systems,
Types of Smart Material
1 PIEZOELECTRIC CERAMICS
2 VISCOELASTIC
3 ELECTRORHEOLOGICAL FLUID
4 SHAPE MEMORY ALLOY
5 OPTICAL FIBRE
6 SMART GEL PH- SENSTIVE POLIMERRS
Piezoelectricity is the ability of some materials (notably crystals
and certain ceramics, including bone) to generate an electric field or electric
potential in response to applied mechanical stress. The effect is closely related
to a change of polarization density within the material's volume. These materials
expand or contract when subjected to a potential difference. Example of piezoelectric
ceramics are quartz ,pb ,zr titanate.
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