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OSIRIS-REx successfully stows sample of asteroid Bennu

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Oct. 29 (UPI) — The asteroid sample collected by NASA’s OSIRIS-REx spacecraft early this month has been safely secured in its return capsule.

“We had originally planned to conduct the stow operation next week, but we’re here to announce today that we’ve successfully completed that operation,” Rich Burns, OSIRIS-REx project manager at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, said during a press conference on Thursday.

Last week, mission engineers were reviewing images of the spacecraft’s sample collection head, the TAGSAM, when they noticed escaping particles.

It turns out, the sample head was so full that a valve called the mylar flap — designed to allow particles into the collection head but not out — had gotten jammed.

Instead of going ahead with maneuvers intended to precisely measure the sample’s mass, mission engineers decided to expedite the sample stow operation.

“Our team quickly redesigned the entire timeline for the stow campaign, which was extremely difficult,” Burns said. “It takes approximately 37 minutes just to confirm that a command has been received by the spacecraft.”

Because of this time-delay in communications between the craft and mission control, and the methodical nature of the stow operation, members of the OSIRIS-REx mission team had to work around the clock.

To ensure each step of the stow operation was completed properly, engineers routinely paused to take photographs and examine their progress. The process involved precisely positioning the TAGSAM’s collector head into the Sample Return Capsule, or SRC, closing it and then conducting tests to ensure it was securely sealed and ready for the trip back to Earth.

“We wanted to only attempt the stow operation one time and make sure we were successful, and we definitely were,” Sandy Freund, a mission support manager for OSIRIS-REx at Lockheed Martin, said during the press conference.

Images collected before and during the stow procedure suggest the collection head only leaked particles when it was in motion — as a result of what engineers called a salt-shaker effect. When spacecraft’s robotic arm and TAGSAM remained motionless, the asteroid sample material remained inside the collection head.

“I was of course concerned about the loss of particles,” said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona, Tucson. “Every one of those particles is scientifically valuable.”

However, Lauretta and the rest of the team said they were confident that there was plenty of sample ready to be returned to Earth for scientific analysis.

“Everywhere that we can see into the TAGSAM, we can see an abundance of sample materials,” Lauretta said. “We are confident that we still have hundreds of grams of sample that we plan to bring back to Earth.”

NASA plans to send OSIRIS-Rex and its asteroid sample on its journey home early next year, but the craft is currently 200 million miles away. The sample won’t make its way to Earth’s surface until the end of 2023.



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Scientists program robot swarm to count penguins

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Oct. 28 (UPI) — Penguins occupy ecosystems increasingly vulnerable to climate change. Tracking their abundance and distribution is vital to the project of tracking global warming’s ecological effects — but counting penguins is difficult work.

To make the task of tallying the size of penguin colonies a bit easier, researchers recruited the assistance of not one robot, but a whole swarm of bots.

“The idea actually grew out of a conversation at my sister-in-law’s wedding,” Mac Schwager, an assistant professor of aeronautics and astronautics at Stanford University, told UPI in an email. “I met our co-author Annie Schmidt at the wedding, and learned that she studies penguin populations in Antarctica, and one of their key challenges was counting the penguins.”

“I told her I worked with autonomous groups of drones that could be used to take images for counting the penguins,” Schwager said. “At that point, it was clear that we had a great research synergy.”

Researchers typically use a single drone to conduct aerial surveys of penguin colonies, but the process is slow and requires a lot of time, effort and skill from the drone pilot.

In collaboration with Schmidt and her team of biologists, Schwager and Stanford grad student Kunal Shah programmed a swarm of drones to autonomously survey penguin colonies.

The team of scientists described their novel solution in a new paper published Wednesday in the journal Science Robotics.

“Our main technical innovation is our path planning algorithm, the computer program that decides where each drone should go and when,” Schwager said. “Existing methods typically plan paths like a lawnmower, or a vacuum cleaner, going back and forth over the survey area.”

“It turns out, other paths can be much more effect, in the sense that they can take the same images while requiring less back-tracking, and while making sure that the drone is close enough to the base camp to make it back safely with the remaining battery life.”

Previously, it took scientists three days to survey Antarctic penguin colonies using a solitary, hand-piloted drone. The robot swarm programmed by Schwager and his colleagues completed surveys in just two to three hours.

Time is precious in Antarctica, where animals are often on the move and weather can quickly take a turn for the worse. But speed isn’t the swarm’s only advantage. The self-piloted robots also offer reliability.

“If one drone fails, the other drones can take up the slack and still finish the survey,” Schwager said.

For now, Schwager’s swarm of drones only take pictures. The counting is done back at base after the survey has been completed and the photographs downloaded onto computers. But in the future, Schwager said the drones could use artificial intelligence to count penguins as they go.

Schwager has previously programmed robotic swarms to track the movement of people and cars on the ground in order to analyze pedestrian and vehicular traffic patterns, and he thinks similar algorithms could be adopted to track animal movements.

“The system could also be used to survey forests and other landscapes for wildfire risk, a problem that is very close to home right now for us at Stanford,” he said. “We could also use the drones to survey construction sites, mining sites, agricultural fields, to assess damage after a natural disaster, or to help find lost hikers.”

Biologists and study co-authors Schmidt and Grant Ballard are currently testing the drone aerial survey system in Antarctica. Meanwhile, Schwager and his colleagues at Stanford continue to make tweaks to the system to help the drones make better in-flight decisions and avoid collisions with birds or drones that have gone astray.

“We are passionate about using teams of autonomous drones to help us to understand and take care of the natural environment around us,” Schwager said.



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Fight judges favor aggression over skill, study shows

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Oct. 28 (UPI) — Often to the chagrin of fans and competitors, wrestling matches, boxing bouts, mixed martial arts and other types of combat competitions are frequently decided by judges.

That’s bad news for competitors that rely more on skill than vigor. New research suggests judges are more likely to award victory to aggressive fighters than skilled fighters, all else being equal.

For the study, published this week in the journal Biology Letters, researchers analyzed data collected from 550 men’s and women’s mixed martial arts contests organized by the Ultimate Fighting Championship.

The data included the percentage of strikes that landed firmly and accurately, a measure of skill, as well as the number of strikes attempted per second, a measure of vigor or aggression.

Regardless of the match conclusion, whether decided by knockout or judges’ decision, the data showed the victor was the more vigorous fighter. However, the correlation between vigor and victory was strongest for matches decided by the scores of the judges.

Fighting skillfully wasn’t entirely discounted. The data showed addition of skill enhanced the advantage of vigor, but the research showed vigor was the most important factor for fights decided by the judges.

“MMA is a fast paced sport and one of the suggestions from our research would be that judges may find vigor easier to assess than skill,” lead author Sarah Lane, postdoctoral research fellow at the University of Plymouth, said in a news release. “That, in turn, leads them to overvalue it when making their decisions, especially in longer fights where one fighter tires more quickly and the disparity in vigor is easier to spot.”

“The advance of technology such as instant replays could potentially counter this, but until they are employed more regularly rate of attack is likely to remain the most important performance trait for victory by decision,” Lane said.

The research was funded by the Biotechnology and Biological Sciences Research Council, which supports studies focused on the role of skill in animal contests.

Most of Lane’s time is spent studying hermit crab fighting, but the authors of the latest paper suggest their analysis of human fights could have implications for understanding physical competitions among animals.

There aren’t typically knockouts in fights between rival animals. Often, males joust and tussle to demonstrate their physical dominance to would be rivals and mates. Like in boxing, a competitor’s performance is subjective.

“Human combat sports provide a unique scenario in which to explore how performance traits such as skill and vigor are perceived, both by participants and observers,” said study co-author Mark Briffa.

“However, because of the obvious communication issues, very little is known about the accuracy with which fighting animals more widely judge the abilities of their rivals,” said Briffa, a professor of animal behavior at Plymouth.



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Graphene-based memory resistors could pave the way for brain-based computing

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Oct. 29 (UPI) — Researchers have created a new computer component capable of toggling between 16 possible memory states — the kind of computing versatility provided by brain synapses.

The new component, called a graphene field effect transistor, described Thursday in the journal Nature Communications, could pave the way for advances in brain-inspired computing.

Modern computers are exclusively digital, featuring two states: on-off or zero and one. Engineers at Penn State University are working to build a computer that replicates the brain’s analog nature, capable of hosting many different states.

If a digital computer’s information processing components work like a light switch, toggling only between on and off, then an analog computer is like a light dimmer.

Scientists have been investigating the potential of brain-based computing for decades, but analog computers have been overshadowed by the advances in traditional computing power. However, the rise of big data and smart devices like self-driving cars has highlighted the need for more computing efficiency.

“We have powerful computers, no doubt about that, the problem is you have to store the memory in one place and do the computing somewhere else,” lead researcher Saptarshi Das, an assistant professor of engineering science and mechanics at Penn State, said in a news release.

All the movement of information required by the bifurcation of memory to logic in modern computers puts a strain on speed. It also requires more spaces. Das and his research partners estimate that their graphene field effect transistor can help eliminate this bottleneck.

“We are creating artificial neural networks, which seek to emulate the energy and area efficiencies of the brain,” said study first author Thomas Shranghamer.

“The brain is so compact it can fit on top of your shoulders, whereas a modern supercomputer takes up a space the size of two or three tennis courts,” said Shranghamer, a doctoral student in the Das group.

Brain synapses can be quickly reconfigured to create a variety of neural network patterns. Likewise, the new graphene field effect transistor, formed by a one-atomic-thick layer of carbon atoms, can be used to control 16 possible memory states.

Researchers were able to reconfigure the transistor, effectively toggling between memory states, by applying a brief electric field to the graphene layer.

“What we have shown is that we can control a large number of memory states with precision using simple graphene field effect transistors,” Das said.

Das and his research partners are now looking to work with semiconductor companies to attempt to scale-up the production of the new technology.



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