Make a loose fist, then rap your knuckles on your forehead. Bang your forearm on the edge of the desk. If you’re near a door frame, kick it lightly, with your shin. Those bones are pretty hard, right? But it’s not just the collagen and calcium phosphate that makes your bones so resistant – it’s the holes that run through them.
Bones are porous. It’s what makes all 206 of them light enough to lug around inside your skin. The intricate network of holes of random sizes, orientations, and shapes – their spinodal microstructure – is part of their great strength, and inspiration for the world of human-made design. Scientists are now imitating bone structure to create lighter, stronger, and more flexible materials to be used in everything from reconstructive surgery to airplane manufacturing.
Honeycomb design is another structural element inspired by nature’s most industrious architects, the bees – although honeycomb is a bit of a misnomer. The structure is actually first a birth pod for bees, and each cell the space in which a larva smoothly transitions into a bumbling adult. Only then is it filled up with honey. Rather than the random spinodal microstructure of bones, honeycomb design features regularly spaced hexagonal cells of uniform size that lay perpendicular to the stress axis. The structure’s strength, even at high volumes, was recognized as far back as the ancient Chinese and Romans.
It’s used to create lightweight high-compressive strength shock absorption in bicycle helmets and motorcycle back protectors, as well as in snowboards. And the honeycomb structure has found its way into less high-impact objects for everyday life, including furniture, lighting and evenwriting instruments.
Another nature-inspired design is the nose of Japanese bullet trains. In the 1990s, the trains caused a loud boom every time they entered a tunnel, due to a cushion of air building up in front of the train travelling at 300kph, causing it to slow down. To solve the problem, chief engineer Eiji Nakatsu considered the kingfisher. The bird’s sharp conical beak allows it to plunge from the sky and into the water without slowing down to snatch its prey. Due to the shape of its beak, the kingfisher makes so little splash or ripples that fish don’t even have time to detect a disturbance in the water before they’re bird food.
By remodelling the front of Shinkansen trains to imitate the kingfisher’s beak – a more pointed shape now seen on high-speed trains from East Asia to Western Europe – the trains became quieter, faster, and more energy efficient.
While these are just a few of the examples, inspiration is everywhere in the natural world. If you’re searching for inspiration for your next design, the best idea might be to just get outside and look.