Observing the fractal spherical formation of swallow nests, it is very intriguing how a hollow structure, made out of a composite compound of mud and fibers, could have such lightweight, yet sturdy properties. The nests in themselves are iterations of one another and the repetition of spheres is never identical. Nest formations have a growing organic form pattern that is coded by nature itself, therefore, the design process includes mimicking this pattern and playing with it by using fibrous material (bamboo fibers) and binding material (mycelium). Later on, carbon fiber is included in the game to create an endoskeleton. The aim of the project is to increase the durability of mycelium and reduce its fragility by supporting it with carbon fiber mesh.

Scientists progress perpetually to improve or invent materials that combine various characteristics such as cost/labour efficiency, durability, and mechanical properties that altogether create more sustainable alternatives to the currently existing conventional materials. With the advances in nanotechnology, new materials and material combinations seem endless. Composite materials (also called a composition material) are combinations of two or more materials produced for a variety of purposes such as; functionality, strength, esthetics etc. Some of the most known composite material examples are concrete, plywood, polyester, epoxy and so forth.

These days the challenging search of the realm of materials has pointed towards the direction of compounds that do not cause harm to the environment in consideration of ongoing pollution and as its consequence; Global Warming. 

Plastic bags, however surprisingly, were found as an environmental solution by its founder Swedish engineer Sten Gustaf Thulin in 1959 as an alternative to paper bags, which were considered detrimental to the environment as they have been identified as a great cause of deforestation. (Independent UK. Phoebe Weston, 2019) Plastics have currently become one of the most infamous and greatest challenges of ours. There is no denying the usefulness of some features of it, namely moldability, production efficiency, and impermeability. In addition, however, to the amount of non-biodegradable waste it generates, plastics also derive from a known to be scarce, valuable component; petroleum.

According to the UN, plastic bags are yet alone produced at a rate of one trillion a year, not taking into account single use plastics such as straws, earbuds, product packaging etc.  Whilst thinking of new inspirations for composite materials and structures we wanted to seize the opportunity of finding alternatives to plastic materials. Therefore we conducted our research with biodegradability in mind. Looking at the fractal spherical formation that are swallow nests, we got intrigued as to how a hollow structure, made out of a composite compound of mud and natural fibers harvested by birds, could be of such lightweight, yet sturdy properties. Inspired by the agglomeration of these shapes, we decided to experiment with more durable yet nonetheless sustainable materials and on variating scales, to see what possibilities this newly formed composite could offer. It is also interesting to note how these nests in themselves are iterations of one another. The repetition of spheres is never identical.

 

 

We did an extended research on existing materials in order to find the right combination to create an interesting composite. Nest formations have a growing organic form pattern that is coded by nature itself, so we worked on mimicking this pattern and played with it using fibrous material (bamboo fibers) and binding material (mycelium). Later on, carbon fiber was included in the game to create an endoskeleton for the material. What we aimed for with this action was to increase the durability of mycelium and reduce its fragileness by supporting it with carbon fiber mesh.

 

 

Materials chosen for composite

Carbon Fiber

Carbon fiber is a chemically compound material which is quite strong. Having a very high ratio of durability / lightness, gives carbon fiber even stronger properties than steel hence its use in high-tech engineering, aviation, and shipbuilding. Some parts of motors which are designed for planes and ships are made out of carbon fiber thanks to other extraordinary features like nonflammability and resistance to pressure. This combination of properties is quite unprecedented. Fibers can be weaved and carbon fiber is no exception, therefore, it can also be guided to perform a specific job. For instance, helicopter wings can only be twisted under one specific direction of applied force, however quite strong and almost unbreakable under any other directions.

Carbon fiber plays an effective role in today’s technological developments and will likely secure its place in near future scenarios. Although it is expensive and has complicated, various, and always developing production methods, it is being considered as one of the most important materials of our time. We are still exploring what else can be achieved with carbon fiber and in which ways we can develop and create new possibilities.

Bamboo Fiber

Bamboo fibers are natural fibers which showcase rapid growth rate, are very lightweight and also show antibacterial properties. It is a trending material among industries such as textile and packaging industries.

Forest protection legislations are expanding and becoming stricter, making wood a valuable and scarce supply. The consequent increase in its price has motivated the development of new technologies and research into alternative materials capable of helping to make up for this deficit. The highly mechanical resistant fibers and their fast growth rate give bamboo an emerging and promising place as a sustainable replacement for industrial purposes.

Being a plant of tropical and subtropical origin, abundant throughout the world and naturally occurring in all continents, bamboo plantations constitute an important source of income and social promotion for populations in lower income countries. Bamboo presents itself as a material with economic potential, as it completes its cycle in a few months and reaches maximum resistance in a few years. Existing use of these fibers range from sheets of paper to MDF (Medium Density Fiberboard). Bamboo-derived panels can be classified according to the manufacturing process, use and applications for which they are intended. The size and shape of their constituent elements (chips, sheets, slats, particles, fibers, flakes, filaments, among others), alone or in combination, profoundly influence the various physical, mechanical and structural characteristics of their properties. In the world, there are approximately 90 genera and about 1200 species of bamboo. Bamboo fibers are the main responsible for their mechanical resistance, constituting 40 to 50% of its composition.

Mycelium

Mycelium is the underground body and root system of mushrooms. It is the largest living being on earth and has a net-like formation that covers and grows in underground soil, feeding on sugar and all kinds of organic materials. It is an incredible material not just because of its unique growth pattern but also because it is hundred percent biodegradable. 

Since mycelium is an organic and therefore self growing material, it requires special conditions and a specific amount of time to grow and fill the desired form. In nature it grows daily and within 2-3 months enters the fruiting process of spurting mushrooms. If regulated and conditioned, it is possible to cultivate mycelium for industrial purposes in a few days. Production process includes basically mixing spores with natural fibers such as wood chips which provide the nutrients necessary for growth. It is also crucial to keep levels of humidity and temperature under control to create the required conditions. Mycelium does the rest by behaving according to its nature and slowly eats the fibre and fills the mold. Afterwards, mycelium is killed by heating/drying in order to stop the growth process. Large blocks of mycelium can be easily produced, lightweight and with good thermal isolation, they are mostly used in the packaging industry as an alternative to polystyrene.

The unique properties of mycelium makes it appealing for possible futuristic usage scenarios. It is the natural filling material that forms a weblike structure and binds the fibers together to keep the form unified.

 

Speculative Uses and Scale-Function Relationship

Two different scales have been considered throughout the process. The composite can be designed in nanoscale and used as a binding and filling material, to the likes of polyurethane foam. In larger scales, it can be used either as a sheet material or can be produced in organic structures by guiding it with a surface weaved with carbon fiber and bamboo fiber.

Furthermore, its characteristics allow that even after an initial formation derived from the compound has been created, more particles of it can be added (just like the arrangement development of swallow nests) . All of this is due to the entanglement and growth pattern of the mycelium as a living, resistant and constantly growing binding component. In its formation (its design), the carbon fibers form a network that structures the shape of the material. Bamboo fiber serves as a substrate for the mycelium to grow and is laid out through this structured network of carbon fiber. Therefore, the density of mycelium is directly proportional to the amount of bamboo fibers used and thus affects stiffness, strength and resistance of the new material.

Bricks, sheets, fabrics, or even organic shapes, are some possible examples. In the example of the brick itself, it could serve as a structure for many types of construction. The joining of one brick to another would take place through the mycelium network and the action of time (with the mass addition of bamboo as a catalyst for mycelium growth). This would cause the carbon structure to be connected by the mycelium network, forming rigid and secure structures capable of supporting weight. Mycelium has also been investigated to be a great material against sonic wave propagation, e.g. a good component to prevent the propagation of earthquake disastrous effects through standing structures. 

Maybe what remains the most interesting feature of this composite material, is that it can be left in its active, living organism state,  or be heated up and thus dried to stop the mycelium growth and make it organically inert. In the latter scenario, the composite can be in contact with human skin and could potentially bring great comfort to the user, as it’s natural, breathable and absorbent. One could imagine an eco-mattress being manufactured with this new foam-like material. Another idea could be to take advantage of the isolation qualities of mycelium and carbon fibers together to create a protective shell against extreme weather conditions. (e.g an alternative to down jackets) 

 

Possible Modifications & Iterations

The initial model has been designed mainly by using Rhino and Grasshopper to be able to acquire a dynamic model that can enable any iterations possible. As a group, we have encountered several problems sourced by MacOS and GH plugins incompatibility, which have impacted our ability to create animation displaying the physical tensile properties of our model. We have therefore moved on to playing with the textures in Zbrush to attain the most realistic fibrous texture of mycelium. As mentioned previously, there are countless iterations possible in terms of agglomeration density of the spheres, their size, and the way they are arranged. Other modifications that could be explored are more related to the inner structure of the nest-like formation, for instance, bamboo fibers can be weaved with carbon fibers to guide the mycelium net more precisely resulting in a smoother surface. However, to achieve more adherence in between agglomerates, bamboo fibers can be assembled in a “looser” manner, which would allow bits of the fibers to stick out of the carbon structure allowing a better mycelium connection. Lastly, one could ponder on the variation or combination of substrate to adjust weight and mechanical properties. Bamboo plant has been already proven to have an affinity with mycelium when used in a binding manner hence our initial preference for this material. 

 

Authors:

Alexandre Nicolet // Fashion Marketing & Communication // Switzerland

Daniel Disitzer Serebrenick // Architecture // Brasil

İlkin Taşdelen // Industrial Design // Turkey

İzem Yılmaz // Sociology // Turkey

 

 

REFERENCES

CHAUDHARY, Abhinav. Infrasonic – A material resonant system –  Issuu.” 2019. https://issuu.com/abhinavchaudhary7/docs/180512_mastertemplate_infrasonic_te.

MARINHO, N. P. Características das fibras do bambu (Dendrocalamus giganteus) e potencial de aplicação em painéis DE. 144. (2012). 

RAVINDAN, Simran. Myco-Tectonics: A Study on Mycelium as an Adhesive in Bamboo Construction. Issuu. 2021. https://issuu.com/simranravindan/docs/myco-techtonics__a_study_on_mycelium_as_an_adhesiv.

WESTON, Phoebe. Plastic bags were created to save the planet, according to son of engineer who first created them. (2019, October 17). The Independent UK. https://www.independent.co.uk/climate-change/news/plastic-bags-pollution-paper-cotton-tote-bags-environment-a9159731.html