Using static electricity, RoboBees can land and stick to surfaces

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Using static electricity, RoboBees can land and stick to surfaces
by Staff Writers
Boston MA (SPX) May 20, 2016


The RoboBee can stick to almost any surface, form glass to wood to a leaf. Image courtesy Harvard Microrobotics Lab and Harvard University. Watch a video on the research here.

Call them the RoboBats. In a recent article in Science, Harvard roboticists demonstrate that their flying microrobots, nicknamed the RoboBees, can now perch during flight to save energy - like bats, birds or butterflies.
"Many applications for small drones require them to stay in the air for extended periods," said Moritz Graule, first author of the paper who conducted this research as a student at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and Wyss Institute for Biologically Inspired Engineering at Harvard University. "Unfortunately, smaller drones run out of energy quickly. We want to keep them aloft longer without requiring too much additional energy."
The team found inspiration in nature and simple science.
"A lot of different animals use perching to conserve energy," said Kevin Ma, a post-doc at SEAS and the Wyss Institute and coauthor. "But the methods they use to perch, like sticky adhesives or latching with talons, are inappropriate for a paperclip-size microrobot, as they either require intricate systems with moving parts or high forces for detachment."
Instead, the team turned to electrostatic adhesion - the same basic science that causes a static-charged sock to cling to a pants leg or a balloon to stick to a wall.
When you rub a balloon on a wool sweater, the balloon becomes negatively charged. If the charged balloon is brought close to a wall, that negative charge forces some of the wall's electrons away, leaving the surface positively charged. The attraction between opposite charges then causes the balloon to stick to the wall.
"In the case of the balloon, however, the charges dissipate over time, and the balloon will eventually fall down," said Graule. "In our system, a small amount of energy is constantly supplied to maintain the attraction."
The RoboBee, pioneered at the Harvard Microrobotics Lab, uses an electrode patch and a foam mount that absorbs shock. The entire mechanism weighs 13.4 mg, bringing the total weight of the robot to about 100mg - similar to the weight of a real bee. The robot takes off and flies normally. When the electrode patch is supplied with a charge, it can stick to almost any surface, from glass to wood to a leaf. To detach, the power supply is simply switched off.
"One of the biggest advantages of this system is that it doesn't cause destabilizing forces during disengagement, which is crucial for a robot as small and delicate as ours," said Graule.
The patch requires about 1000 times less power to perch than it does to hover, offering to dramatically extend the operational life of the robot. Reducing the robot's power requirements is critical for the researchers, as they work to integrate onboard batteries on untethered RoboBees.
"The use of adhesives that are controllable without complex physical mechanisms, are low power, and can adhere to a large array of surfaces is perfect for robots that are agile yet have limited payload - like the RoboBee," added Robert Wood, Charles River Professor of Engineering and Applied Sciences at SEAS and a core faculty member of the Wyss Institute, and senior author of the study. "When making robots the size of insects, simplicity and low power are always key constraints."
Right now, the RoboBee can only perch under overhangs and on ceilings, as the electrostatic patch is attached to the top of the vehicle. Next, the team hopes to change the mechanical design so that the robot can perch on any surface.
"There are more challenges to making a robust, robotic landing system but this experimental result demonstrates a very versatile solution to the problem of keeping flying microrobots operating longer without quickly draining power," said Ma.
The paper was coauthored by Pakpong Chirarattananon, Sawyer B. Fuller, Noah Jafferis, Matthew Spenko and Roy Kornbluh. The research was funded by the National Science Foundation, the Wyss Institute for Biologically Inspired Engineering, and the Swiss Study Foundation.

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Australian, U.S. HIFiRE rocket achieves Mach 7.5
by Richard Tomkins
Canberra, Australia (UPI) May 18, 2016

Australia and the United States have successfully fired an experimental rocket with a speed of more than seven times the speed of sound.

The rocket, which reached an apogee, or highest altitude, of about 172.7 miles, is part of a joint research program called HIFiRE, or Hypersonic International Flight Research Experimentation Program. It is being conducted by Australia's Defense Science and Technology Group and the U.S. Air Force Research Laboratory with Boeing and the University of Queensland providing expert technical design and analysis.

The aim of the program is to explore fundamental technologies critical for sustained hypersonic flight, which is five times and more of the speed of sound.

"The success of this test launch takes us one step closer to the realization of hypersonic flight," said Dr. Alex Zelinsky, chief scientist of the Australian Department of Defense. "It is a game-changing technology identified in the 2016 Defense White Paper and could revolutionize global air travel, providing cost-effective access to space."

The experimental rocket was launched the Woomera Test Range in South Australia.

The Australian Department of Defense said the targeted speed achieved was Mach 7.5, or seven and a half times the speed of sound. The speed of sound in dry air at 68 degrees Fahrenheit is about 1,126 miles per second, or 768 miles per hour.

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Orbita, a ghost of Chernobyl in the heart of Ukraine
By Yulia SILINA
Orbita, Ukraine (AFP) May 20, 2016


Missing from maps, a ghost town hides in the pine forests of central Ukraine, abandoned after the Chernobyl nuclear disaster but now filling with families fleeing the pro-Russian eastern separatist war.

Orbita, a town whose existence was never registered by the Soviet authorities, was meant to house 20,000 workers at a nuclear power plant whose construction was abandoned after the Chernobyl disaster of April 1986.

The road through the woods that leads to the site is dilapidated, the sign marking the town's entrance covered with rust, but two small playgrounds next to the abandoned buildings are clean and tidy.

Alina, a blonde 10-year-old with a grin and few worries on her mind, is playing next to her grandfather Vladimir Limarchenko, a man who has lived through many hard times.

Her family left their home in the former Soviet republic's industrial heartland almost as soon as the fighting erupted two years ago, in a conflict which has since killed more than 9,300 people and forced 1.7 million from their homes.

"We did not know where to go. We just took a train to central Ukraine, where our relatives live. And by chance our fellow traveller at the station told us about Orbita," said Limarchenko, who worked as a mechanic before retiring.

His new neighbour Vasiliy came to Orbita from the pro-Russian separatist city of Lugansk a few months ago and is now renovating a damp apartment in a five-storey building that stood empty for many years.

"My home was seized by the rebels so I have nowhere to return to. Life is very expensive everywhere, but here I took an apartment on credit for a very low price," said the 36-year-old, who lives on a disability pension.

"It is better to live in the forest than under fire," he added.

- Abandoned lives -

Eight families from various parts of the war-scarred east have relocated to Orbita, attracted by its cheap prices and calm.

It costs less than $1,500 (1,300 euros) to buy one of the Soviet-era apartments, a pittance compared to the average $40,000 that people pay in the capital Kiev.

Orbita's tale is tightly intertwined with that of Chernobyl, whose explosion spewed radiation across nearly three-quarters of Europe and left several thousand people dead or dying.

Plans for the town were initially drafted in 1970, the year ground was broken for the Chygyryn nuclear power plant, whose construction was never completed.

Authorities of then-Soviet Ukraine planned to make Orbita the home of engineers from the plant -- in what was intended to be the equivalent of Pripyat, a city of 48,000 built three kilometres (two miles) from Chernobyl.

In the 1980s, two nine-storey and two five-storey apartment buildings, a department store and all the necessary infrastructure were built.

But the disaster at Chernobyl, the world's worst nuclear accident, meant plans to complete the Chygyryn plant were quickly abandoned and because the Communist party had not yet opened an outpost in the town, it was not considered to exist officially and was not included on maps of the region.

Residents of Orbita employed to make preparations for the opening of the power plant lost their jobs and the town was quickly deserted, becoming a silent monument to the shock and terror caused by Chernobyl that reverberated through corridors of power in the Kremlin and around the world.

"There has been no heating or drinkable water here for a very long time," Alina's grandfather said.

"We are similar to Chernobyl, except that there is no radiation. On the contrary -- we have clean forest air," he added.

- 'A post-apocalyptic movie' -

The town, which is proving a draw for the poor from other parts of Ukraine, is currently home to about 50 families who are living in the two five-storey apartment blocks.

Most are elderly, live without heating and gas and have to trek to a nearby village for water. They survive, for the most part, on meagre pensions and vegetables grown in their gardens.

But their hardscrabble existence is not made any easier by another nuisance -- curious tourists who come to snap pictures of the peculiar town and who have decided to make it their home.

Kristina, a 19-year-old student from Uzhgorod, a city near Ukraine's western border with Slovakia, came with a group of friends looking for a thrill.

"We wanted to visit Chernobyl, but it is very expensive. You can get here for free and there is no radiation," she said.

"I was intrigued by the atmosphere of this ghost town," she admits.

"It is like being in a post-apocalyptic movie."

But Limarchenko is hardly impressed.

"Do we look like ghosts?" he asks glumly.

"The real ghost towns are now in the separatist east, in the places we came from."