C haptEr 9 design Environments and systems
296
only more efficiently, but to carry loads far higher than would be
possible if the body were forever frozen into a single static position. Many responses are intrinsic and could be described in terms
of sensory inputs and actuated responses associated with a whole
class of “smart” structures. Interestingly, anticipatory repositioning
can also occur, as happens when an individual a priori assumes a
particular stance with the cognitive expectation of needing to carry
a certain type of load—an action associated with “intelligent” structures. Instead of a structure simply passively carrying the forces
applied to it, structures that actively change shape or otherwise
actively respond in an intrinsic or anticipatory way to the type and
location of applied forces can be envisioned. There are, of course,
active structures available now, but the promise of nanotechnologies allows imagining a scenario of much smaller and even more
active systems (as embedded sensor, actuation, and control systems
become smaller). Integrated energy storage or acquisition capabilities also provide a bright future.
nano-Based structural/mechanical applications
In common structural and mechanical applications that use
relatively large components, limitations on the size and scale of
nanomaterials that can be directly synthesized lead to the use of
nanocomposites. Nanocomposites are normally designed to exploit
various properties of the respective materials used. As discussed in
Section 8.8, typically one material is chosen as a matrix to hold
or embed smaller quantities of nanomaterials as a second phase.
The matrix can be a polymer, metal, or ceramic. Commonly used
matrix materials are typically available in bulk form and are relatively inexpensive. Smaller quantities of higher-performance but
typically more expensive nanomaterials are then incorporated into
the matrix or deposited as a film onto a matrix substrate.
Objectives of developing structurally useful nanocomposites vary
greatly. An obvious application is in the areas of strength and stiffness.
Here the type and composition of the nanocomposite depend greatly
on the anticipated size of the final piece. Many attractive nanocomposites remain possible to fabricate at very small-scale dimensions.
Large-scale nanocomposite production demands a form of bulk
manufacturing that is still difficult and expensive, but approaches
such as embedding nanoparticles into metallic matrix are entirely
feasible (see the discussions that follow). Other objectives might be
quite different. For passive vibration control, the use of various nanoparticles in a rubber or polymeric matrix offers great potential. These
applications are explored in the following subsections.
296
only more efficiently, but to carry loads far higher than would be
possible if the body were forever frozen into a single static position. Many responses are intrinsic and could be described in terms
of sensory inputs and actuated responses associated with a whole
class of “smart” structures. Interestingly, anticipatory repositioning
can also occur, as happens when an individual a priori assumes a
particular stance with the cognitive expectation of needing to carry
a certain type of load—an action associated with “intelligent” structures. Instead of a structure simply passively carrying the forces
applied to it, structures that actively change shape or otherwise
actively respond in an intrinsic or anticipatory way to the type and
location of applied forces can be envisioned. There are, of course,
active structures available now, but the promise of nanotechnologies allows imagining a scenario of much smaller and even more
active systems (as embedded sensor, actuation, and control systems
become smaller). Integrated energy storage or acquisition capabilities also provide a bright future.
nano-Based structural/mechanical applications
In common structural and mechanical applications that use
relatively large components, limitations on the size and scale of
nanomaterials that can be directly synthesized lead to the use of
nanocomposites. Nanocomposites are normally designed to exploit
various properties of the respective materials used. As discussed in
Section 8.8, typically one material is chosen as a matrix to hold
or embed smaller quantities of nanomaterials as a second phase.
The matrix can be a polymer, metal, or ceramic. Commonly used
matrix materials are typically available in bulk form and are relatively inexpensive. Smaller quantities of higher-performance but
typically more expensive nanomaterials are then incorporated into
the matrix or deposited as a film onto a matrix substrate.
Objectives of developing structurally useful nanocomposites vary
greatly. An obvious application is in the areas of strength and stiffness.
Here the type and composition of the nanocomposite depend greatly
on the anticipated size of the final piece. Many attractive nanocomposites remain possible to fabricate at very small-scale dimensions.
Large-scale nanocomposite production demands a form of bulk
manufacturing that is still difficult and expensive, but approaches
such as embedding nanoparticles into metallic matrix are entirely
feasible (see the discussions that follow). Other objectives might be
quite different. For passive vibration control, the use of various nanoparticles in a rubber or polymeric matrix offers great potential. These
applications are explored in the following subsections.