Towards a Cleaner Future: The Cactus-Inspired Oil Skin

???Oil spills are a very difficult problem. In addition to being catastrophic to the local environment, they are also incredibly difficult to clean up. After a spill occurs, some always stays on the surface while the rest forms heavy droplets and sink downwards, either becoming suspended in the water or falling to the bottom. Getting at these bits of the slick is difficult, and current methods are neither cost effective nor environmentally friendly themselves.

For example, the containment booms and chemical dispersants that BP used after the Deepwater Horizon spill were highly ineffective, as anyone who followed the news of the spill will recall. Because of that disaster, and others besides, numerous solutions have been proposed to deal with spills in the future – ranging from filters, to tiny submarines, and oil-eating bacteria.

artificial_cactusBut most recently, a group of researchers from the Chinese Academy of Sciences have suggested a nature-inspired solution. Their concept calls for droplet-collecting “skins” modeled after cactus plants. In the desert, these pants collect moisture when condensation covers the tips of their spines and then falls under its own weight to the base and gets absorbed by the plant.

Working from this, the Chinese researchers created their own “cactus skin” – artificial cone-shaped needles made of copper and coated in silicone that. When submerged in water, the half-millimeter spikes draw down oil droplets and collect them at the bottom. According to the researchers, the method is good for 99% of oil-water mixes and works with several types of oil.

chinese_academy_of_scienceThe research appeared in the latest issue of the journal Nature Communications. According to the paper:

Underwater, these structures mimic cacti and can capture micron-sized oil droplets and continuously transport them towards the base of the conical needles. Materials with this structure show obvious advantages in micron-sized oil collection with high continuity and high throughput.

The researchers think the device could also be used in the open air to remove fine droplets released with sprays. This way, they would be able to neutralize a good portion of oil released by malfunctioning rigs before it began polluting our oceans and waterways. On top of that, research at the Academy, specifically in the Institute of Chemistry, has revealed that this same concept might provide a solution to the problem of city pollution.

Between all of this, we could be seeing artificial cactuses in city environments very soon. Just not as potted plants and in the desert! And it does say much about our biomimetic future, where we are becoming increasingly dependent on solutions born of nature to solve our environmental problems.


The Future is Here: The Autonomous Robotic Jellyfish!

Matt Russiello submerges the RoboJelly. Remember the Medusoid, that creepy robot jellyfish creature that debuted in July of 2012? Well, it seems that Virginia Tech was working on their own, with help from the military. Yes, whereas the medusoid was a project in organic-synthetic interfacing, a collaborative effort between Harvard University and Caltech researchers, this one is the result of ongoing work by the United States Navy.

After years of working on their own model for a robot jellyfish, they unveiled the fruits of that labor earlier this month. Named Cyro – a contraction of robot and Cyanea capillata (the species name for the lion’s mane jellyfish) – this 170 pound biomimetic machine looks and act like a jellyfish, but is in fact an autonomous robot.

cyro1And much the Medusoid and Robojelly – Cyro’s hand-sized predecessor – this second-generation model utilizes what is called “Bio-Inspired Shape memory Alloy Composites (BISMAC)” in order to mimic the motions of the real thing. This consists of a
layer of smart materials (aka. shape memory alloy) that is soft and shaped in such a way to maximize deformation and propulsion.

Underneath this layer of composite material are a number of actuators (i.e. robotic arms) that control the movements of the Cyro. These in turn are mounted on a central body that contains enough hardware to allow the robot to communicate, gather information, and make decisions. What’s more, the developers envisage a fleet of networked Cyros, conducting surveillance and research and sharing the results with each other.

cyro2And as the video below explains, this robot jellyfish is likely to have numerous applications. These included environmental monitoring, cleaning up oil spills, or conducting military surveillance. Of course, it seems pretty obvious what the primary use of the Cyro is going to be, given that the ONR and the U.S. Naval Undersea Warfare Center are responsible for funding it!

No telling how Human Right Watch will react to this, though. How safe would you feel, knowing that the next time you’re snorkeling, swimming or ocean kayaking that a perfectly innocent looking Man-of-War could be spying on you? Check out the video of the Cyro being tested below: