Background
The word programmable matter is a concept originally invented by Toffoli and Margolus in 1991 to refer to a collection of elements in fine-grained computation arranged in space. It defined a computing substrate composed of computing nodes that communicate using only closest-neighbor interactions. When semiconductor manufacturing, nanotechnology, and other areas of science have progressed, the concept has evolved to illustrate the fact that a collection of elements that can be “programmed” can be designed to alter their physical properties in practice, not just in simulation. [3]
Approaches to the Idea
Reconfigurable robots follow a type of programmable matter at one end of the continuum where the individual components are usually within the size range of centimetres. At the other hand, a large number of diverse bases for programmable matter exist at the nanoscale end of the spectrum, ranging from shape-changing molecules to quantum dots. Examples from the micrometer to submillimeter scale include MEMS-based units, cells that were developed using synthetic biology, and the principle of utility fog. [4]
One solution to this principle could be external to the material, and could be accomplished by the “application of light, voltage, electric or magnetic fields, etc.” (McCarthy 2006). It is evident in materials like liquid crystals. Another more ambitious approach is that the individual units of the ensemble will process information, and a shift in the physical properties of the ensemble is the consequence of their computation. This principle is dealt with in terms like claytronics. [4]
Examples of Programmable Matter
- Complex fluids: Many complex fluids – mixtures which coexist in two phases: solids and liquids – can be categorized as programmable matter. Liquid crystals will be an example as stated earlier, and are found in items such as mood rings or laptops. [3]
- Metamaterials: These are artificial composites that can be controlled to react in non-natural ways. One example developed by David Smith and then by John Pendry and David Schuri is of a material that can have its refractive index tuned to allow it to have a particular refractive index at various points in the sample. This may in turn result in a “invisibility mask” if properly tuned. [3][4]
Robotics-Based Approaches
- Self-reconfiguring modular robotics: Modular robotics self-configuring is an area in robotics in which a group of simple robot modules work together to dynamically form shapes and build behaviors appropriate for several tasks, similar to programmable subjects. [3]
▲“The Promise and Peril of Programmable Matter” (Engineering.com) [4]
- Claytronics: An evolving technological area relating to reconfigurable nanoscale robots, also known as catoms, which are built to shape devices or structures of much greater size. [4][5]
- Synthetic Biology: A research directed at manipulating cells that are commonly used to build larger structures that can be engineered using synthetic genetic networks such as genetic toggle switches, to change colour, form, etc. [4][3]
Usage
▲“Climate-Active Textiles — Self-Assembly Lab” (Self-Assembly Lab) [1]
- Climate-active textiles: MIT ‘s Self Assembly Lab and the Ministry of Supply’s MIT-born apparel business have created Climate-Active Textiles which continuously adjust to temperature changes to keep the individual comfortable. A modern style of textile will turn its porosity for breathability, insulation thickness and compression or match shape reversibly. [1]
▲“Origami robot folds itself up, crawls away” (Hardesty, L) [5]
- 4D printing: 4D printing employs the same 3D printing methods to create a three-dimensional structure by computer-programmed deposition of the material in successive layers. 4D printing also provides the transition element over time. A successful 4D printing trial was achieved by the cooperation of Self-Assembly Lab, Stratasys, and Autodesk. This technique helps the substance to change its structure using only water, fire, light or some other basic energy input. [2][5]
[1] Climate-Active Textiles — Self-Assembly Lab. (2014). Self-Assembly Lab. Self-Assembly Lab. https://selfassemblylab.mit.edu/climateactive-textiles. Last accessed: 2020/02/13
[2] 4D Printing — Self-Assembly Lab. (2014). Self-Assembly Lab. Self-Assembly Lab. https://selfassemblylab.mit.edu/4d-printing. Last accessed: 2020/02/13
[3] Wikipedia Contributors. (2020, July 5). Programmable matter. Wikipedia; Wikimedia Foundation. https://en.wikipedia.org/wiki/Programmable_matter. Last accessed: 2020/02/13
[4] The Promise and Peril of Programmable Matter. (2017). Engineering.Com. https://www.engineering.com/DesignerEdge/DesignerEdgeArticles/ArticleID/14967/The-Promise-and-Peril-of-Programmable-Matter.aspx. Last accessed: 2020/02/13
[5] Hardesty, L. (2014, August). Origami robot folds itself up, crawls away. MIT News | Massachusetts Institute of Technology. https://news.mit.edu/2014/mobile-folding-robots-0807. Last accessed: 2020/02/13
[6] Hornigold, T. (2018, April 29). Stuff 3.0: The Era of Programmable Matter. Singularity Hub. https://singularityhub.com/2018/04/29/stuff-3-0-the-era-of-programmable-matter/ Last accessed: 2020/08/23
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