10 INCREDIBLE ADVANCES IN BIOMIMICRY

10 Incredible Advances In Biomimicry
By Andrew Handley, Listverse, 30 November 2013.

Biomimetics is the science of looking to nature for answers to our technological problems. You use biomimetic technologies every single day. Velcro, for example, was invented after George de Mestral noticed how burrs used tiny hooks to stick to his dog’s fur. And while Velcro is too commonplace to blow anybody’s mind, in recent years, we’ve used the exact same process to build technologies that are nothing short of incredible.

10. UltraCane

In nature, ultrasound is most famously used by bats to find prey. The science behind it’s pretty simple: You shoot out a sound wave and record the amount of time it takes for the echo to return after bouncing off something. If you know how fast the sonic wave is traveling, you can measure how far away the obstacle is. Bats do it naturally. Humans don’t.

So researchers at the University of Leeds in the UK looked to bats for inspiration to build an ultrasonic cane for blind people. The idea was simple enough, but what they didn’t foresee was the way the human brain became so receptive to the new sense. The cane works by sending out ultrasonic signals, measuring the response time of the echoes, and converting that data into vibrations in the handle of the cane. As an object gets closer, the vibrations get stronger.

When the cane was tested, they found that the brains of the test subjects readily accepted the input and began building a new type of spatial awareness based solely on vibrations coming in through their palms. Over time, they stopped consciously feeling the vibrations and built an instant mental map of their surroundings - their minds cut out the middle man in favour of a more efficient interpretation of the sensation.

9. Swarm Robotics

Harvard isn’t the only research organization intent on giving robots the ability to communicate and learn from each other. The New Jersey Institute of Technology is also developing a swarm of robots with a hive mentality, and they’ve already succeeded. Modelled after the colony behaviour of ants, a robot is able to pick up on the decisions of the other robots and follow their behaviour - without any programming.

The robots themselves don’t look like ants - more like futuristic ice cubes - but each one has two light sensors that act like an ant’s antennae picking up a trail of pheromones. Individually stupid, the robots can only move forward and sense light. Each robot was being tracked by a projector that left spots of light along their path, sort of like a trail of breadcrumbs, and each time a robot stumbled across another robot’s path, the lights got brighter.

At the beginning of the experiment, all the robots were moving randomly and chaotically. At the end, they converged into a train following a single path. Like ants, they don’t make a “choice” when they do something different; it’s all based on a core program that tells them to follow a specific signal. With ants, that signal is a pheromone trail left by other ants. With swarm robots, it’s light.

8. Self-Cleaning Paint

Not all advances in biomimicry have to do with robots. In fact, the majority don’t; robots are just more interesting to talk about. That said, one of the most interesting biomimetic inventions in recent years is a paint that’s modelled after the leaves of the lotus flower.

Lotus leaves may look smooth, but at the microscopic level, they’re covered in millions of tiny spikes. The spikes repel dirt and water by minimizing the surface area of the leaf - water just rolls off because there’s not enough contact to build an attraction. With that as a model, a German company developed a paint that uses a complex microstructure on the outside to prevent things from sticking to the paint. Under a microscope, the dried paint looks like a surreal landscape covered with sculptures.

Dirt particles can still get caught on the protrusions, but the smallest splash of water will dislodge them. In other words, the paint is essentially self-cleaning. And like the lotus leaves, water itself slides right off. NASA is also using the lotus idea to build a coating for spacesuits and rovers to prevent bacteria from hitchhiking into space.

7. Multifaceted Cameras

If you had a microscope, a lot of time, and a lazy fly, you could count all the individual facets in the eye of a housefly. There are about 28,000 - each with its own lens and light-sensing nerve. Compound eyes are one of the marvels of nature: They allow insects to see up to 180 degrees around them and offer a sense of depth that humans can only dream about.

Using that idea, researchers at the University of Illinois built a multifaceted camera that consists of 180 lenses, each connected to an individual photo detector. The array was built onto a flexible rubber mat which was then curved into a hemispherical shape. The input from all the lenses is combined into a single image, so you’re looking at a regular picture as opposed to, say, a bank of monitors. And the whole thing - lenses and electronics included - is only a centimetre (.4 in) in diameter.

The team’s goal is to use the cameras for aerial surveillance on robotic drones. But even a stationary camera would be a massive improvement over current cameras. Put two of these “bug eyes” back to back, and you have a 360 degree view. Currently, they’re working on a new model that doubles the number of lenses.

6. Shark Skin Coatings

When Michael Phelps won six gold medals in the 2004 Olympics, he was wearing a swimsuit called Fastskin, developed by Speedo. Fastskin is covered in tiny bumps that emulate the skin of a shark. Even though the swimsuits have been simultaneously banned and declared ineffective, the idea of using shark skin as a model for hi-tech materials is far from dead.

A shark’s skin is covered in a layer of overlapping pieces called denticles. They look like microscopic teeth and point toward the back of the shark. When a shark swims, the leading edges of the denticles create micro vortices that essentially pull the shark forward, allowing it to swim faster. And due to the way they flex, other organisms - like algae and barnacles - can’t grab onto it. That’s why whales are often found encrusted with barnacles, but sharks never are.

The US Navy is researching applications to use shark skin-inspired coatings on the outside of their submarines, which would both make them faster and prevent mussels and barnacles from piling up on their hulls, the clean-up of which is a US$50 million-per-year job. Hospitals are also getting in on the game: A material known as Sharklet is already being used on door handles in California’s hospitals to stop pathogens like E. coli from forming colonies. The best part is, since it’s not a chemical repellent, there’s no way for bacteria to build a resistance.

5. SCRATCHBot

The search for new ways to experience the world has always been rooted in the animal world. By building a robot that looks and acts like a rat, the scientists at the University of Sheffield have delved into a means of sensing that humans will never experience: whiskers. Dubbed SCRATCHBot, the robot’s sole purpose is to act as a vehicle for state-of-the-art synthetic whiskers - and a brain that can interpret the data and put it to use.

Since rats are mostly nocturnal, they often use their whiskers to navigate more than their eyesight. In recreating a set of functional whiskers, the researchers used fiberglass rods that contained Hall effect sensors (sensors that measure differences in voltage based on a current and a magnetic field). Small magnets in the whiskers provide the magnetic field, and when the whiskers brush against something, the sensors catch the voltage change from the movement of the magnets. This allows the SCRATCHBot to “see” objects through the whiskers.

The “brain” of the rat is a PC-based neural model that receives information from the whiskers, processes it, and sends a command to the legs (turn left, turn right, etc.). The entire design is based on an incredibly stupid rat - it has no high level cortex, but can still operate basic motor functions.

4. Organic Solar Cells

Dye-sensitized solar cells are a type of solar cell that use a special form of dye to capture solar energy. When sunlight hits the dye, it’s molecules react and produce electricity. These solar cells are cheaper than their silicon counterparts, but they have one problem: The dye tends to break down after a short amount of time, essentially leaving you with a useless square of plastic.

But the mechanism of the dye isn’t much different from what you find in natural photosynthesis when a plant converts sunlight into energy. So researchers at North Carolina State University started looking at houseplants to see what made them different. The result was a solar cell with an internal vascular system that cycles dye through a branched network of veins. When the dye degrades to the point that it’s no longer producing any electricity, it’s cycled out and replaced with a fresh stream of dye, like a plant delivering nutrients to its leaves.

3. The T8 SpiderBot

If spiders are the stuff from which nightmares are born, the T8 Octopod Robot is a nightmare with a price tag. Roboticists have been trying for years to mimic the architecture of a spider. With eight legs, you get an unprecedented level of stability, which is perfect for search-and-rescue robots in disaster areas. And while we’ve had other versions of spiderlike robots, it’s always been difficult to design one with enough internal control for all eight legs to move in unison, while still retaining the ability to move separately when needed.

The T8 Octopod Robot uses a unique movement engine designed specifically to overcome that obstacle. It’s remote-controlled, and with a simple command the on-board processor will calculate leg trajectory, motor control, and inverse kinematics to coordinate its 26 individual motors. The result is almost too life-like.

2. Self-Healing Circuits

Integrated circuit chips are used in virtually every electronic device created today, and despite their small size, most chips have millions of transistors spread across a surface no wider than the head of a nail. If one tiny piece breaks, the entire thing becomes useless. But what if your cell phone or your computer could repair itself like an immune system fighting off an infection? That might be a very real possibility in the near future.

Engineers at the California Institute of Technology have created what they call “indestructible circuits.” To demonstrate, they stuck one under a microscope, melted it with a laser, and watched it figure out a way to keep working. The chips are microscopic; it would take about 75 to cover the face of a penny. In addition to all the circuitry needed for the chip’s main purpose, each chip also contains a variety of sensors and an on-board central processor that detects damage and figures out the most efficient way to get everything back up and running again.

They’ve tested dozens of chips outfitted with the self-healing capability, and no matter what part of the chip is destroyed, it always finds a way to reroute the circuit’s processes in less than a second. And it’s not pre-programmed for any specific threats, like the body’s immune system, it assesses the damage on its own and figures out what actions it needs to take. The only thing remaining for us to do is locate John Connor.

1. Parasitic Skin Grafts

There is a parasite called the Pomphorhynchus laevis that uses spikes in its head to rip a hole in an animal’s intestines, after which, it shove its head inside and inflates its body to hold itself in place. It’s this unlikely monstrosity that has inspired medical researchers to develop a new type of skin graft. Skin grafts are patches of skin that are transplanted from one part of the body to another, usually to cover a severe burn.

Until now, skin grafts were usually held in place with staples, which carry a high risk of infection. This new biomimetic skin graft, on the other hand, copies almost everything from the most terrifying parasite you’re likely to read about today. The graft has a cluster of micro-needles that swell when they’re exposed to water. The needles go into the skin fairly easily, and once inside, they puff out like a balloon to hold the graft in place. Another advantage over staples, which actually end up tearing the tissue around them, is that the micro-needles push tissue to the side, rather than damaging it.

[Source: Listverse. Edited.]