Difference between revisions of "Mechanical metamaterial"

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(Some few more concrete examples: added line-breaks & some fices)
 
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=== Future ===
 
=== Future ===
  
Future mechanical metamaterials based on [[gemstone like compounds]] (in particular based on [[base materials with high potential]])
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Future mechanical metamaterials based on [[gemstone like compounds]] <br>
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(in particular based on [[base materials with high potential]])
 
* [[gemstone based metamaterial]]s
 
* [[gemstone based metamaterial]]s
  
 
Many unusual properties are (will be) possible. <br>
 
Many unusual properties are (will be) possible. <br>
 
For more examples see: [[Metamaterial#Examples]]
 
For more examples see: [[Metamaterial#Examples]]
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 +
=== Some few more concrete examples ===
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 +
* (Passive) '''auxetic metamaterials:''' Metamaterials which use their non actuated internal structure to create a '''negative Poisson ratio'''. <br>That is they expand transversally (sidewards) when stretched longitudinally (lengthwise) and they contract transversally when compressed longitudinally.
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* Metamaterials with (clearly independent) internal degrees of freedom deliberately left under-constrained. <br>If the small structural pieces are sheet shaped and the hinges allow compression to complete collapse without destruction one ends up with [[origami]] like structures. <br>Note that metamaterials are by far not limited to [[origami]] structures. <br>Such structures can be made active structures by adding actuators independently acting on the separate degrees of freedom.
 +
* Metamaterials using internal flexing or hinging to act as complex mechanisms / machines. <br>Giving up on long range periodicity (translation symmetry) symmetry blurs the line to [[Nanomachinery|(nano)machinery]] and ([[Nanomechanical computation|nano]])[[mechanical computation]]. <br>What makes a metamaterial is the presence of at least a little bit of repetition.
  
 
== Non-mechanical metamaterials ==
 
== Non-mechanical metamaterials ==
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* [[Thermal metamaterial]]
 
* [[Thermal metamaterial]]
 
* [[Electrical metamaterials]]
 
* [[Electrical metamaterials]]
* ... many more
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* ... many more other types of [[metamaterial]]s
  
 
== Related ==
 
== Related ==
  
 
* '''[[Digital control over matter]]'''
 
* '''[[Digital control over matter]]'''
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* '''[[Emulated elasticity]]'''
 
* '''[[Metamaterial]]'''
 
* '''[[Metamaterial]]'''
 
* [[Gemstone based metamaterial]]
 
* [[Gemstone based metamaterial]]

Latest revision as of 08:25, 5 December 2023

Up: Metamaterials

Mechanical metamaterials are materials that emulate mechanical properties through structuring at smaller size-scales.
This is relative. Mechanical metamaterials can have their base structures at all scales.
E.g. Cainmaille is crude, textiles are fine. For base structures at the nanoscale see: Gemstone based metamaterial

Reversible assembly is highly desirable.
See: Digital control over matter

Clear delineation to optical metamaterials

The term "Metamaterial" without prefix is often used to refer to optical metamaterials. This may be because:

  • Many existing mechanical metamaterials already have a name and are not consciously recognized as such (see below)
  • More advanced mechanical metamaterials are maybe experimentally less accessible than optical metamaterials (questionable ...)

Examples for (mechanical) metamaterials: past, present, future

Metamaterial
out of the past: chain maille
Base-material: metals
Structure-size: clearly visible
Metamaterial
of today: textiles
Base-material: plastics
Structure-size: microscopic
Metamaterial
of the future: "gem-gum"
Base-material: gemstones
Structure-size: a few atoms

Today

Known and existing cases of (passive) mechanical metamaterials are:

  • Chainmaille
  • Textiles
  • many natural materials produced by living organisms (bones with structured voids, naca with layered protein and minerals, ...)
  • .. there may be a few more that constitute whole different classes ??

Future

Future mechanical metamaterials based on gemstone like compounds
(in particular based on base materials with high potential)

Many unusual properties are (will be) possible.
For more examples see: Metamaterial#Examples

Some few more concrete examples

  • (Passive) auxetic metamaterials: Metamaterials which use their non actuated internal structure to create a negative Poisson ratio.
    That is they expand transversally (sidewards) when stretched longitudinally (lengthwise) and they contract transversally when compressed longitudinally.
  • Metamaterials with (clearly independent) internal degrees of freedom deliberately left under-constrained.
    If the small structural pieces are sheet shaped and the hinges allow compression to complete collapse without destruction one ends up with origami like structures.
    Note that metamaterials are by far not limited to origami structures.
    Such structures can be made active structures by adding actuators independently acting on the separate degrees of freedom.
  • Metamaterials using internal flexing or hinging to act as complex mechanisms / machines.
    Giving up on long range periodicity (translation symmetry) symmetry blurs the line to (nano)machinery and (nano)mechanical computation.
    What makes a metamaterial is the presence of at least a little bit of repetition.

Non-mechanical metamaterials

The complement to mechanical metamaterials are the non-mechanical metamaterials. These include:

Related

External links

  • Auxetics – one peculiar example of an nigh infinite amount of possibilities