Author – Elakhya N
Albert Einstein once said “if we look deep into nature, we will understand everything”. Today, copying ideas from our environment and creating engineering technologies by mimicking nature to solve human needs has become a new technology named ‘Biomimicry’. Velcro is the earliest examples of humans mimicking nature. Swiss engineer George de Mestral went for a walk in the woods in 1941 and wondered if the burrs that clung to his trousers could be turned into something useful.
The nano-scale hair-like structures inside the toes of a gecko enable it to crawl up a wall. The force between the nano-structured hair in its foot and atoms of the wall are strong enough to hold up together, which makes it wander freely on walls. This mechanism has inspired many researchers, who are creating new engineering materials that resemble gecko-like nano-structures for adhesion. Latest developments in bio-mimicry technology make it possible to utilize the gecko foot nano-structures in medical applications as alternatives to conventional chemical adhesives that cannot be used for some medical procedures.
Janine Benyus, an American natural sciences writer and an innovation consultant who established Biomimicry 3.8 states that human beings were neither the first ones to build houses nor the first to process cellulose and make paper. She started searching for innovations done by plants and animals that can be utilized to solve human problems. Janine Benyus wondered if biomimetic building parts can used in such a way that get a building can work like an organism. Soon, her first project in urban planning project in Lavasa, a new hill resort in India took shape.
Lavasa inspired by banyan fig leaves and harvester ants
In India, a new hill resort and a bio-mimetic city named Lavasa has been constructed by HCC Group with the help of an architectural firm, HOK. Spread across 12,000 acres in a Western Ghats valley located outside Pune, the new city has been designed using Biomimetic technology. The idea was to restore 70% of the deforested land through detailed landscaping, reforestation and slope greening, reduce 30% of carbon emissions, 65% of potable water consumption, and 95% of waste sent to landfills. The site’s original ecosystem was a moist deciduous forest, which was converted into an arid landscape in recent times.
Working closely with biologists from Biomimicry 3.8, HOK has built a bio-mimetic city at Lavasa. The city’s rooftops are inspired by the morphology of the native banyan fig leaf, whose pointed spear shape at the end that hastens the water run-off and cleans its surface in the process. It has led to the development of tiled shingle rooftops that shed water in the same way. Since the Western Ghats region is prone to seasonal flooding from monsoons and a strategy based on ant nest has been adopted to channel water through the city. This efficient plan is inspired from the local harvester ants that divert water away from their nests through multi-path, low-grade channels. Further, water has been stored in networked building foundations, much like tree roots.
Similarly, HOK is building another project at Khed Special Economic Zone in Maharashtra, which is inspired from cliff swallows. A polymer has been utilized that stiffens soil to create the same stabilizing effect as cliff swallows version of mortar that holds their nests to buildings, and is made by mixing mud with their saliva. Strategically placed catch basins, check dams, and living roofs are being also used to collect rains for irrigating farms in the valley below the hills. Further plans include painting offices and apartment towers with skins of photo-voltaic cells, so that buildings act as solar panels.
Termites inspire energy efficient buildings
Termites are expert builders that maintain constant temperature inside their habitat through heat and cold. This ability has inspired the Eastgate Centre in Harare, Zimbabwe, a shopping complex, designed by architect Mick Pearce that does not require conventional heating or air-conditioning. Since it is designed based on the interior temperature regulation of African termite mounds, the building’s energy consumption is just 10% of the energy used by any conventional building. Similarly, wasps building their nests with mud and their saliva have inspired 3-D printed local affordable housing out of mud. Massimo Moretti and his team at the World’s Advanced Saving Project are carving out a future for innovative low cost housing using earth, the most abundant local building material available.
Namibian beetle inspires water collection
A small insect found in the Namibian desert fulfils its water needs from fog. The Namibian desert beetle has learnt to materialize water out of thin air by using the bumps on the back of its wings, which attract dewdrops. Fog gets deposited on these water-loving tips and goes down along waxy sides into the critter’s mouth. Qinetiq, an aerospace firm, and Grimshaw, an architecture firm has adopted this technique to design new materials for coating aircraft that repels frost and on buildings to collect water, which is 10 times more effective than fog-catching nets.
Coral effect for eco-friendly cement
A cement manufacturing company named Calera in the US utilized a recipe from the coral reef using carbon dioxide as a building block in cement and concrete. Blue Planet is the second-generation technology to Calera, which is inspired by natural biomineralization of carbonate materials under mild conditions, similar to corals, which use carbon dioxide and calcium to grow carbonate minerals in oceans. The cement industry is responsible for 5% of global carbon emissions, with each ton of cement producing a ton of CO2 and the new formula can actually sequesters half a ton of CO2. Brent Constantz, from Calera hopes to make production of environment-friendly cement by capturing flue gases from factories, running them through a saline solution, and using electricity to convert these gases into solids.
Nanotech Biomimicry in India
Nanotechnology has taken a firm foothold in India in recent years and is in an advanced development stage. Engineering a material as a replica of nature at a nano-scale is not a simple task. Indian researchers have utilized the lotus leaf effect to engineer a surface, which self-cleans and finds its applications in self-cleaning toilets/wash basins/glasses, etc. Courses in design paradigm inspired by biomimicry are being conducted at IIT-Bombay.
Further, Indian Institute of Science, Bangalore too is carrying research on biomimetic nanotechnology, materials science, chemical engineering and product development. The department of Aeroscience Engineering at IIT-Madras is studying biomimetic flows as well. IIT-Kanpur is also carrying out research in biomimetics for human tissue engineering. Meanwhile, Biomimicry India has teamed up with the Srishti Institute of Art, Design and Technology to create a biomimicry lab in Bengaluru.
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