Rewritten Article:

In a breakthrough that’s straight out of science fiction, a team of engineers at Caltech has developed a real-life Transformer that can morph in mid-air, allowing it to smoothly transition from flying to rolling on the ground. This innovative technology has far-reaching implications for commercial delivery systems and robotic explorers, making it an exciting development in the field of robotics.

The new robot, dubbed ATMO (aerially transforming morphobot), uses four thrusters to fly but can transform into a ground-rolling configuration using a single motor that lifts its thrusters up or down. This unique design allows ATMO to change its shape and function seamlessly, enabling it to adapt to various environments and situations.

According to Ioannis Mandralis, the lead author of the research paper published in Communications Engineering, “We designed and built a new robotic system inspired by nature – by the way that animals can use their bodies in different ways to achieve different types of locomotion.” For example, birds fly and then change their body morphology to slow themselves down and avoid obstacles. Mandralis adds, “Having the ability to transform in the air unlocks a lot of possibilities for improved autonomy and robustness.”

However, mid-air transformation also poses challenges due to complex aerodynamic forces that come into play both because the robot is close to the ground and because it is changing its shape as it morphs. Mory Gharib, the Hans W. Liepmann Professor of Aeronautics and Medical Engineering, notes that “Even though it seems simple when you watch a bird land and then run, in reality this is a problem that the aerospace industry has been struggling to deal with for probably more than 50 years.”

To better understand these complex aerodynamic forces, the researchers ran tests in Caltech’s drone lab using load cell experiments and smoke visualization. They fed those insights into the algorithm behind a new control system they created for ATMO, which uses advanced model predictive control to continuously predict how the system will behave in the near future and adjust its actions accordingly.

“The control algorithm is the biggest innovation in this paper,” Mandralis says. “Quadrotors use particular controllers because of how their thrusters are placed and how they fly. Here we introduce a dynamic system that hasn’t been studied before. As soon as the robot starts morphing, you get different dynamic couplings – different forces interacting with one another. And the control system has to be able to respond quickly to all of that.”

The potential applications of ATMO are vast and exciting, from commercial delivery systems to robotic explorers. With its unique ability to transform in mid-air and adapt to various environments, this technology has the potential to revolutionize the field of robotics and beyond.

Researchers at the University of California, Irvine (UCI) have made a groundbreaking discovery in the field of materials science. By expanding on a classic model developed over 70 years ago, scientists in UCI’s Samueli School of Engineering have gained new insights into the behavior of advanced materials critical to energy systems, space exploration, and nuclear applications.

The traditional Frank-Read theory attributed slip band formation to continuous dislocation multiplication at active sources. However, the UC Irvine team found that extended slip bands emerge from source deactivation followed by the dynamic activation of new dislocation sources. This process was observed at the atomic scale through mechanical compression on micropillars made of a chromium-cobalt-nickel alloy.

Using advanced microscopy techniques and large-scale atomistic modeling, researchers were able to visualize the confined slip band as a thin glide zone with minimal defects and the extended slip band with a high density of planar defects. This understanding has shed new light on collective dislocation motion and microscopic deformation instability in advanced structural materials.

Deformation banding, where strain concentrates in local zones, is a common phenomenon in various substances and systems, including crystalline solids, metals, granular media, and even geologic faults under compressive stress. The discovery of extended slip bands challenges the classic model developed by physicists Charles Frank and Thornton Read in the 1950s.

“This foundational knowledge will accelerate the discovery of materials with tailored and predictable mechanical properties to meet the rising demand for advanced materials resilient to extreme environments across energy and aerospace sectors,” said corresponding author Penghui Cao, UC Irvine associate professor of mechanical and aerospace engineering.

The research was funded by the U.S. Department of Energy, UC Irvine, and the National Science Foundation (through the UC Irvine Center for Complex and Active Materials). The project involved graduate students, research specialists, and other professors from UCI’s Department of Mechanical and Aerospace Engineering and Department of Materials Science and Engineering.

The article discusses a recent study led by University College London researchers that suggests using existing large planes, like the Boeing 777F, to inject particles into the atmosphere to reflect sunlight and cool the planet. This approach, known as stratospheric aerosol injection, is a geoengineering technique that has been previously researched but assumed to require specially designed aircraft flying at high altitudes.

The study found that injecting sulphur dioxide particles at an altitude of 13 km above the polar regions could meaningfully cool the planet, albeit less effectively than at higher altitudes closer to the equator. This approach would require using three times the amount of aerosol and would have increased side effects like acid rain.

However, climate change is a serious problem, and it’s essential to understand all options for policy-makers to make informed decisions. The researchers used simulations in the UK’s Earth System Model 1 (UKESM1) to estimate the impact of stratospheric aerosol injection at different altitudes, latitudes, and seasons.

Injecting 12 million tonnes of sulphur dioxide a year at 13 km would cool the planet by around 0.6°C, which is roughly the same amount added to the atmosphere by the eruption of Mount Pinatubo in 1991. This strategy is not as effective as injecting particles at higher altitudes but could begin sooner.

The study’s lead author noted that any stratospheric aerosol injection would need to be introduced gradually and reduced gradually to avoid catastrophic impacts from sudden warming or cooling, and would not eliminate the need for emissions reductions. The researchers emphasized that long-term climate stability can only be achieved with net-zero greenhouse gas emission reductions.