Lab-Grown Earthquakes Reveal the Frictional Forces Acting Beneath Our Feet
Simulating an earthquake on a miniature scale in a laboratory known unofficially as the "seismological wind tunnel," engineers and seismologists have produced the most comprehensive look to date at the complex physics of friction driving destructive thrust-fault earthquakes. "Simulating earthquakes in a lab lets us observe how these brief and violent events grow and evolve by ‘slowing down' their motion through high-speed photography and optics," says Ares Rosakis, the Theodore von Karman Professor of Aeronautics and Mechanical Engineering. [Caltech story]
EAS Remembers Jakob van Zyl
Jakob van Zyl, Senior Faculty Associate in Electrical Engineering and Aerospace, passed away on August 26, 2020 at the age of 63. He came to Caltech in 1982 and received his M.S. and Ph.D. in Electrical Engineering in 1983 and 1986, respectively. He joined JPL in 1986 and retired in 2019 as the Director of Solar System Exploration. He was world-renowned for his research in imaging radar polarimetry. He made pioneering contributions to the design and development of many synthetic aperture radar (SAR) systems, including SIR-C, SRTM, AIRSAR, TOPSAR, and GeoSAR. He held management roles at JPL including, Director for Astronomy and Physics (2006-2011), Associate Director of Project Formulation and Strategy (2011-2015), and Director of Solar System Exploration (2016-2019). He received many honors and awards, including an honorary doctorate from his alma mater, the University of Stellenbosch in South Africa in 2015 for his contributions to space missions, for being a good ambassador for Africa, and for inspiring young scientists and engineers in his home continent. Over the last two decades, he taught EE/Ae 157 Introduction to the Physics of Remote Sensing. He contributed in numerous ways to promote interactions between EAS and JPL.
Jakob van Zyl
Machine Learning Helps Robot Swarms Coordinate
Soon-Jo Chung, Bren Professor of Aerospace, Yisong Yue, Professor of Computing and Mathematical Sciences, postdoctoral scholar Wolfgang Hönig, and graduate students Benjamin Rivière and Guanya Shi, have designed a new data-driven method to control the movement of multiple robots through cluttered, unmapped spaces, so they do not run into one another. "Our work shows some promising results to overcome the safety, robustness, and scalability issues of conventional black-box artificial intelligence (AI) approaches for swarm motion planning with GLAS and close-proximity control for multiple drones using Neural-Swarm," says Chung. [Caltech story]
Rahul Arun Receives 2020 Henry Ford II Scholar Award
Mechanical Engineering student Rahul Arun, advised by Professor Aaron Ames and Beverley McKeon, is a recipient of the 2020 Henry Ford II Scholar Award. Rahul's academic interests lie at the intersection of theoretical, numerical, and experimental fluid mechanics, with an emphasis on turbulent flows. This summer, he will be working as a SURF fellow under Professor Tim Colonius to conduct fast and adaptive numerical simulations of vortex ring collisions. In the more distant future, his plan is to attend graduate school. The Henry Ford II Scholar Award is funded under an endowment provided by the Ford Motor Company Fund. The award is made annually to engineering students with the best academic record at the end of the third year of undergraduate study.
Henry Ford II Scholar Award
Microstructures Self-Assemble into New Materials
A new process developed at Caltech makes it possible for the first time to manufacture large quantities of materials whose structure is designed at a nanometer scale—the size of DNA's double helix. Pioneered by Professor Julia R. Greer, "nanoarchitected materials" exhibit unusual, often surprising properties—for example, exceptionally lightweight ceramics that spring back to their original shape, like a sponge, after being compressed. Now, a team of engineers at Caltech and ETH Zurich have developed a material that is designed at the nanoscale but assembles itself—with no need for the precision laser assembly. "We couldn't 3-D print this much nanoarchitected material even in a month; instead we're able to grow it in a matter of hours," says Carlos M. Portela, Postdoctoral Scholar. "It is exciting to see our computationally designed optimal nanoscale architectures being realized experimentally in the lab," says Dennis M. Kochmann, Visiting Associate. [Caltech story]