ROBOTS that mimic the Venus flytrap could run on live insects and spiders, snatching and digesting them for fuel. Now two prototypes have been developed that employ smart materials to rapidly ensnare their prey.
Venus flytraps (Dionaea muscipula) catch insects using two specially adapted leaves. When a bug lands it brushes tiny hairs on the surface, triggering the trapping mechanism. The leaves snap shut in a mere 100 milliseconds, and the plant kills and digests its quarry (see diagram).
Recreating this method means finding materials that can not only detect the presence of an insect but also close on it quickly. At Seoul National University in South Korea, Seung-Won Kim and colleagues have done this using shape memory materials. These switch between two stable shapes when subjected to force, heat or an electric current.
The team used two different materials - a clamshell-shaped piece of carbon fibre that acts as the leaves, connected by a shape-memory metal spring. The weight of an insect on the spring makes it contract sharply, pulling the leaves together and enveloping the prey. Opening the trap once more is just a matter of applying a current to the spring.
Mohsen Shahinpoor at the University of Maine in Orono took a different approach. His robot flytrap uses artificial muscles made of polymer membranes coated with gold electrodes. A current travelling through the membrane makes it bend in one direction - and when the polarity is reversed it moves the other way.
Bending the material also produces a voltage, which Shahinpoor has utilised to create sensors. When a bug lands, the tiny voltage it generates triggers a larger power source to apply opposite charges to the leaves, making them attract one another and closing the trap (Bioinspiration and Biomimetics, DOI: 10.1088/1748-3182/6/4/046004).
"We should be able to benefit enormously from these flytrap technologies," says Ioannis Ieropoulos of the Bristol Robotics Lab in the UK. He and colleagues previously developed Ecobot, a robot that can digest insects, food scraps and sewage to power itself. Ecobot uses bacteria to break down a fly's exoskeleton in a reaction that liberates electrons into a circuit, generating electricity.
But without a way to catch prey, the researchers either manually feed Ecobot with dead flies or use an ultraviolet bug lure - like those used in restaurants. That's no good for an autonomous robot, though. What's more, UV lures need to be on all the time, wasting precious power, says Ieropoulos. "We'd be happy to talk to these groups about their flytraps."
Rena containers the big threat: expert
WED, 12 OCT 2011 1:22P.M.NZD
Oil spilling from the stricken ship Rena may cause short-term environmental damage, but the bigger headache may be containers floating just below the surface, an expert warns.
There were 1368 containers on board Rena before it ran onto the Astrolabe reef off Tauranga last week and started to spill fuel oil. The ship was thrown about in rough seas and 70 shipping containers were lost overboard on Tuesday night.
Following the experience with containers falling off the ship Napoli off the English coast in 2007, Simon Boxall, from the University of Southampton's National Oceanography Centre, said floating containers were potentially more worrying now than leaking fuel oil.
"Once they break away from the ship they present a hazard to shipping - often floating just below the surface and difficult to see and track." The containers can remain afloat for weeks at a time before they fill with water and sink, and their contents should also be concern, Dr Boxall said. "This could range from household goods to chemicals and in the case of Napoli there were several tonnes of herbicides amongst other materials." Dr Boxall said that with just 350 tonnes of fuel oil spilled so far from the Rena when it was 12km offshore, the damage will be short term.
"The focus should be on securing the ship and its cargo and dealing with oil as and when it reaches shore."The blobs of oil - emulsified oil often called mousse - can be collected by hand from the beaches, he says. Dr Boxall also said there should not be any undue concern about using the oil dispersant Corexit 9500 as it was one of the less toxic dispersants, and only two tonnes had been used so far. Chemicals in the Rena's cargo include hydrogen peroxide, potassium nitrate and alkysulphonic liquid and trichloroiscyanuric acid, which is highly toxic in water. There is also ferrosilicon, which emits flammable gas when in contact with water.
However, Victoria University's Professor Neil Curtis told NZ Newswire that would happen slowly, and overall the chemicals were unlikely to cause any great problems if they fell into the sea because they would be so highly diluted."I can't imagine there's anything to worry about, compared to 1700 tonnes of oil." Maritime New Zealand said none of the 11 containers listed as containing hazardous goods had gone into the sea.
Fighting for the forest, battling against the dam
By Chularat Saengpassa
The Nation ( Daily English Newspaper in Thailand)
Activist Seng Khwanyuen goes on the offensive to protect his forest from the disastrous environmental effects were the Kaeng Sua Ten dam to be built
Almost two decades after the controversial Kaeng Sua Ten dam project in Phrae province seemed to have been shelved, activist Seng Khwanyuen finds himself preparing to go into battle once again. Flood-hit residents in neighbouring provinces recently started calling on the government to dust off the project and put an end to their miseries.
A kamnan in Song district, Seng says this time he hopes to ensure that the dam project is shelved permanently.
And if he cannot manage to achieve that in his lifetime, he's pinning his hopes on the future generations of tambon Sa-Iab residents.
"They've been 'indoctrinated' to continue the fight," says the 58-year-old.
The first batch of youngsters, called "Takon Yom" [Sediments of the Yom River], all of whom have been trained from a very young age, have now graduated from various universities with some having gone on to study for their master's degrees. "They work and live elsewhere but will return home whenever they are needed to fight off the dam project," he adds.
"We stick to our position: 'No Kaeng Sua Ten dam, and we will not move out. We insist on that now and we will do the same in the next 50 years," he says.
Seng is not being bull-headed: he feels for the flood-affected people but says the dam is not the solution. And science backs him up.
Studies and research by a large number of institutes, the Thailand Development Research Fund, have concluded that Kaeng Sua Ten dam project, which would flood a vast area in Mae Yom national park where it would be sited, could not prevent seasonal flooding in the province, nor in Sukhothai, Phitsanulok and Phichit.
Seng has given lectures and attended numerous meetings in those provinces to meet with residents and explain to them about the studies and research, but continues to face criticism. They accuse Sa-iab residents of being selfish. "Even Phrae residents in other areas still say we lack insight and fail to foresee the benefits of the dam project," he says.
"In addition to research and studies, I always ask them why provinces located south of many dams built along the Ping, Wang and Nan Rivers are still flooded each year."
These days, Seng goes out less often to meet with residents and assigns the task to younger activists on the Takon Yom team.
Seng and his friends are currently meeting with Sukhothai residents to discuss the issue and he claims they are reaching an understanding. "I don't want to hear anything like 'victory belongs to Phrae residents while defeat goes to those in Sukhothai'. It's not productive. I want residents in both provinces to enjoy a win-win situation without the Kaeng Sua Ten dam existing, which would be best for all," he says.
A network of locals living in the four-province region, called the Yom River network, has been set up comprising residents living in 98 tambons, thanks to more understandings being reached, he explains. Members of the network are frequently invited to visit tambon Sa-iab to see with their own eyes just how useful and beneficial the forest is to everyday life.
Six thousand people now live in Tambon Sa-iab. Along with the some 3,000 homes that would be flooded if the dam were built, the country would lose 29,569 rai of fertile forests, another 28,831 rai of forest reserves, 21,481 rai of Mae Yom national park, and 11,206 rai of golden teak forests, the country's most fertile and complete.
Seng says the forests and canals in tambon Sa-iab are so rich in food that most residents live for days without money, simply by harvesting plants and fish. "With only Bt100, some families can live four or five days buying only the non-food items they need.
He's looked closely at the lives of residents driven from their homes as a result of other dam projects, including Pak Mool dam in Ubon Ratchathani and Pa Sak Chonlasit dam in Lop Buri, and is saddened at how local cultures and lifestyles have been lost, in addition to the permanent loss of natural sources of foods and insufficient compensation.
Seng, who left school at the end of fourth grade, is currently taking adult education classes and striving to complete his high-school diploma. He's also learning computer skills, which he says are important for his lectures. "Computer literacy is difficult for me, but the audience would not be convinced by my explanations alone without figures and details shown to them in graphic form during lectures and meetings," he says.
"Forestland is for us to conserve because it benefits humans in so many ways. Sa-iab people will protect their forest until their last breath" __________________________________________________________________
In April, seven traditional Polynesian ocean-going vessels called vakas, and their 16 member crews, set sail on a 15,000 nautical mile journey across the Pacific. Powered only by solar energy, guided solely by celestial navigation, these seafarers are on an expedition to reconnect with their ancestors and raise awareness for the environmental issues threatening the Pacific.
The vakas are equipped with a solar electrified motor that can drive the canoe 30 nautical miles. The solar-powered engine runs off of 2000 watts of electricity, which is about the same amount of power it takes to run a microwave. The engine gets its power from a solar panel that is built onto the aft of the canoe. The solar-powered motor is located under the deck of the canoe and there is a panel that opens which provides access to the motor from the deck.
The vakas have sailed over a hundred thousand nautical miles with only one major maintenance fix. During their sail into Monterey, the mast on the Hine Moana snapped, but it was quickly fixed and all of the vaka sailed down to Los Angeles. The canoes are incredibly durable and have gone through severe weather on the Pacific.
From the head Captain of the Pacific Voyagers, Magnus Danbolt:
The solar powered electrified motors are one of a kind. They were designed by David Czap’s Dutch company called Cveers which is no longer in existence. They are custom made for the vaka. Each vaka has 8 solar panels that peak out on the aft of the vaka. They have a battery bank of 31 kilowatts and they drive 2 electrical pods. The propellers on the engines can be used as generators when there is no sun. They are powered by lithium batteries that are self-regulated and self-controlled. The engines are retractable and can be taken out of the water when the vakas sail onto a beach.
There is one nautical control for the engines. It has an on and off switch along with a LED display that shows the state of the charge, how much has been used, and how much power is coming in from the sun.
Like bejewelled galleons of another age frozen on the dark sea, the drilling platforms are beautiful. They twinkle like constellations in the night. Beautiful, but toxic.
The stink of oil has just washed over the deck. After running on clean solar power for months, it’s a pretty filthy wake up call. It’s everywhere, in the whare, in the hulls, all around us. As I sit here I can taste ‘civilisation’ and it’s not pretty. I’ve been told that every one of these platforms, and there are about 20 in a 40 mile stretch of coast, that every one of them has had some sort of spill. Not a great surprise, but when you consider that the true cost of your fuel has never been included in the price, it’s a travesty.
Not only do our fossil fuel vehicles and manufacturing techniques pour CO2 into the air and therefore the sea, but they support companies who have little interest in the environment other that what they can get out of it. The move to clean fuel sources is fundamental to what we’re doing. We’re in a transition period, so start transitioning. Reduce the use of your vehicle, write to your local councils and encourage them to change to clean machines, walk, get a bike, ride a horse (I know horses fart, but I think cars fart worse).
What we’re looking at is a change of pace. Life will happen a little slower, but you know what? I think that’d be fantastic for us, for our families, for society as a whole. We’re so hell-bent on screaming around like lunatics, racing thru the traffic of Life that half of us die young(ish) from stress. We’ve been sold a dream that isn’t real. The consumer dream of bigger houses, faster cars, more ‘stuff’ and it’s just nonsense. What makes most of us happy is good connections with others and the world around us. That will only come by allowing yourself a little more time to breath and relax.
Congratulations and a Pacific Voyagers Gold Star of Commitment to Madeline who sent us this message: “…I find myself asking smaller to-go (takeaway) food establishments if I could bring my own cup and plate/utensils to serve their food/bev for myself. Many say yes! It's a conscious start and maybe more people will catch on.”
Madeline you are our hero. People like you give us hope that all this is worth doing. I’m sure there are others stepping out as community leaders (because that’s what you are), but it’s really nice for us to hear about it. If you're doing it and/or have already told us, give yourself a Gold Star. Thanks, kia kaha, keep it up.
Life is not a race, you don’t win if you get to the finish first.