“The spines of the hedgehog” explained zoologist Julian Vincent, in a paper in 1986, “are as short as possible while still able to bend when loaded axially. In addition, the hedgehog spines have an internal morphology which delays the onset of local buckling under these loads, thus enabling the spines to absorb larger amounts of mechanical energy… their main function is that of a shock-absorber when the animal falls from a height”.
When mechanical engineer Dr Nikolay Bogatyrev was asked to design a protective cover for a laptop, his thoughts turned to hedgehogs. Hedgehogs, he reasoned, can fall from heights without coming to any harm.
Dr Bogatyrev is a lecturer in the Mechanical Engineering Department of Bath University and runs a design consultancy called BioTRIZ. His book The Inventor’s Manual helps “make the process of creativity and problem-solving logical, systematic and rational, thus increasing the efficiency of your thinking.” Much of his creative thinking is inspired by nature.
Great artists steal
Biotechnology is all about harnessing the forces of nature. In medicine, for example, we use viruses to deliver drugs into cells. But in the discipline of biomimetics – otherwise known as bionics or biomimicry – we learn design tricks from nature.
Go-faster swimming costumes are modelled on shark skin; ship hulls have micro-rippled surfaces copied from mussels to prevent them from getting dirty; and fish that can survive under an extraordinary weight of water can teach us lessons about muscle resilience.
For centuries we have been drawing inspiration from nature. Leonardo da Vinci sketched a flying machine with flapping wings, an idea taking up by intrepid birdmen at the start of the twentieth century. Early designs for a steam locomotive envisaged the steam engine powering giant legs – an ‘iron horse’. What these pioneers realised was that after millions of years of evolution nature has perfected certain things, and carries out functions a great deal better than mankind can engineer them. Natural systems, such as photo-synthesis, are extraordinarily efficient and sustainable. Unlike man-made mechanical systems they don’t wear out nor do they require any maintenance. They can teach us a lot.
Engineers are increasingly interested in biomimetics, and success stories abound. According to Nature magazine, “millions of years of development have made the biological world into a supremely effective material-development laboratory”. Amongst other examples it cited gecko feet that can cling to any surface, the remarkable strength of spider and silkworm thread and the skin of the sea cucumber, soft and pliable until a predator comes near and causes it to stiffen.
Biomimetics has domestic uses, but it also has world-changing potential
In February a BBC programme ‘Biomimetics – Designed by Nature’ featured the work of Dr David Branson. He is designing flexible robotic arms based on octopus tentacles.
Dr Veronica Kapsali has made a fabric that becomes alternately waterproof and ventilated according to the weather conditions. Her inspiration was the pine cone, which closes up in wet conditions, before opening out to release its seeds when it is dry. Most remarkable of all was Suzanne Lee’s ‘Biocouture’. She makes clothing material by culturing a mixture of yeast and bacteria. She likens this to ‘vegetable leather’. It is not only biodegradable, but compostable. So when you have worn a shirt for long enough you can just throw it in the compost bin with the vegetable peelings and turn it into compost for the garden.
These ideas may sound wacky but biomimetics is more than this. Dr Bogatryev has undertaken projects for the European Space Agency, for the Ministry of Defence and Procter and Gamble. For Philips he designed a microfluidic pump for viscous liquids that was based upon biological cilia, the minute hairs that flap in rhythmic waves to propel mucus away from our lungs.
Meanwhile scientists from Ohio State University have developed a mesh inspired by the lotus, which absorbs oil but repels water. By creating the exact opposite they believe they could make a mesh that could clean up oil spills by capturing the oil while allowing the water to filter through.
Increasingly we are working with nature, and learning how to turn natural forces to our advantage. Plant science is all about this. By genetic modification and by mak-ing the photosynthesis more efficient we can speed the growth of trees. Futuragene is a company that does exactly this. Its high yielding GM eucalyptus tree has been approved for planting in Bra-zil, and it can both feed the local paper industry and ameliorate the problem of deforestation.
“Look deep into nature,” said Albert Einstein,”and then you will understand everything better.” Today we are looking into nature like never before. Nature is driving a burst of innovation from new medicines to compostable clothing.