【推荐1】Most animals can quickly transition from walking to jumping to crawling to swimming if needed without making major adjustments. Most robots cannot. But researchers at Carnegie Mellon University have created soft robots that can seamlessly shift from walking to swimming or crawling to rolling.

“We were inspired by nature to develop a robot that can perform different tasks and adapt to its environment without adding actuators (执行器) or complexity,” said Carmel Majdi, a professor in the Mechanical Engineering Department in CMU’s College of Engineering. “Our bistable (双稳态) actuator is simple, stable and durable, and lays the foundation for future work on dynamic, reconfigurable soft robotics.”

Matching how animals transition from walking to swimming to crawling to jumping is a big challenge for bio-inspired and soft robotics. For example, one robot the team created has four curved actuators attached to the corners of a cellphone-sized body made of two bistable actuators.

On land, the curved actuators act as legs, allowing the robot to walk. In the water, the bistable actuators change the robot’s shape, putting the curved actuators in an ideal position to act as propellers so it can swim.

“You need to have legs to walk on land, and you need to have a propeller to swim in the water. Building a robot with separate systems designed for each environment adds complexity and weight,” said Majidi. “We use the same system for both environments to create an efficient robot.”

The team created two other robots: one that can crawl and jump, and one inspired by caterpillars and pill bugs that can crawl and roll. The actuators require only a hundred millisecond of electrical charge to change their shape, and they are durable.

In the future, the robots could be used in rescue situations or to interact with sea animals or coral. Using heat-activated springs in the actuators could open up applications in environmental monitoring, haptics (触觉) and reconfigurable electronics and communication.

【推荐2】Soil is one of the most important materials of daily life. It’s necessary for growing the food and resources we depend on, protecting against drought (干旱) and flooding and storing carbon dioxide for years to come. But the dirt under our feet is constantly in danger because of rising temperatures and loss of biodiversity caused by climate change. Although we may think soil is simple, it’s pretty hard to know what’s really going on deep in the ground from the surface.

Scientists in Italy, however, think they may have a robotic solution—a seed-inspired (受种子启发的) robot. Scientists at the Bioinspired Soft Robotics (BSR) Lab have developed the first 4D-printed seed-inspired soft robot, which can act as sensors for monitoring pollutants, CO2 levels, temperature and humidity (湿度) in soil.

They were inspired by a South African geranium (a garden plant). The seeds of the plant have the ability to change shape in response to how humid their environment is. When the time comes for the seeds to leave the plant, they can separate themselves from the plant and move independently to find their way through soil. The curly seeds can find a home for themselves simply by becoming bigger or smaller depending on the water content in the air. The team imitated the seeds and developed robots that use materials that also change shape when exposed (暴露) to humidity.

When tested in a soil sample, the robot was able to rock from side to side, adapt its shape to the space, and get into holes in the ground like a natural seed. Not to mention, it was capable of lifting things about 100 times its own weight. First author Luca Cecchini said that the robot is easy to break down and causes no harm to the soil. It could be used as a wireless, battery-free tool for surface soil exploration and monitoring.

【推荐2】A 2021 York University study showed that weekly dance training improved motor function and daily living for those with mild Parkinson’s disease. So what is it about dance that’s different from other exercises?

Helena Blumen, a scientist at Albert Einstein College of Medicine in New York City, says the mental multitasking that dance requires activates various parts of the brain at the same time, which can lead to the building of better connections across different brain regions. Basically, dancing requires more “brain power” than simpler repetitive exercises.

While scientists are still learning how dancing works in the brain, a clearer picture is beginning to take shape. In 2018, researchers at Otto-von-Guericke University Magdeburg in Germany, did MRI scans (扫描) of older adults who had taken part in one of the two programs over six months: one group practiced dance and the other did a traditional exercise program with cycling and strength training.

Both groups improved their level of physical fitness, but the dancers grew more white and grey matter in the parts of the brain that are responsible for cognitive (认知的) processes. What’s more, the dancers showed an increase in blood plasma BDNF, a factor known to play an important role in the development of brain capacity (能力). Together, the researchers suppose, these brain changes contribute to more of the brain’s ability to form new connections and pathways.

In a different study in 2022, Blumen and other researchers from Albert Einstein College of Medicine found that social ballroom dancing, when compared with treadmill walking among adults over 65, was connected with diminished possibility of developing Alzheimer’s disease and improved overall quality of life.

Similar studies have shown the benefits of dance in conditions ranging from MS to Huntington’s disease or other mental illnesses. Dance therapy (疗法) might even help people with brain injuries. A small Finnish study of 11 people with severe brain injury showed that dance-based therapy may improve mobility, cognition and overall well-being.