News & Events

09-20-23

Late last year, Caltech researchers revealed that they had developed a new fabrication technique for printing microsized metal parts containing features about as thick as three or four sheets of paper. Now, the team has reinvented the technique to allow for printing objects a thousand times smaller: 150 nanometers, which is comparable to the size of a flu virus. In doing so, the team also discovered that the atomic arrangements within these objects are disordered, which would, at large scale, make these materials unusable because they would be considered weak and "low quality." In the case of nanosized metal objects, however, this atomic-level mess has the opposite effect: these parts can be three-to-five-times stronger than similarly sized structures with more orderly atomic arrangements.

The work was conducted in the lab of Julia R. Greer, the Ruben F. and Donna Mettler Professor of Materials Science, Mechanics and Medical Engineering; and Fletcher Jones Foundation Director of the Kavli Nanoscience Institute. It is described in a paper appearing in the journal Nano Letters. [Caltech story]

Tags: APhMS research highlights MCE Julia Greer Wenxin Zhang

04-25-23

Inspired by the mechanics of a phase of matter called liquid crystals, researchers have developed the first three-dimensional model of a layer of cells and the extrusion behavior that emerges from their physical interactions. From this new model, the team discovered that the more a cell is squeezed by its neighbors in a particular symmetric way, the more likely it is to get extruded from the group. [Caltech story]

Tags: research highlights GALCIT MCE Jose Andrade Guruswami Ravichandran

12-01-22

Engineers at Caltech have developed a method for 3-D printing pure and multicomponent metals, at a resolution that is, in some cases, an order of magnitude smaller than previously possible. "We had to develop a new way of doing it, and we couldn't rely on heat to build our structures," says Max Saccone. [Caltech story]

Tags: APhMS research highlights MedE MCE MCE Julia Greer Max Saccone Rebecca Gallivan Daryl Yee Kai Narita

10-26-22

Once considered science fiction, technology capable of collecting solar power in space and beaming it to Earth to provide a global supply of clean and affordable energy is moving closer to reality. Through the Space-based Solar Power Project (SSPP), a team of Caltech researchers is working to deploy a constellation of modular spacecraft that collect sunlight, transform it into electricity, then wirelessly transmit that electricity wherever it is needed—including to places that currently have no access to reliable power. "This is an extraordinary and unprecedented project," says Harry Atwater, Otis Booth Leadership Chair, Division of Engineering and Applied Science; Howard Hughes Professor of Applied Physics and Materials Science; Director, Liquid Sunlight Alliance. "It exemplifies the boldness and ambition needed to address one of the most significant challenges of our time, providing clean and affordable energy to the world." [Caltech story]

Tags: APhMS EE research highlights MedE MCE Harry Atwater Ali Hajimiri Sergio Pellegrino

08-26-22

Inspired by the way termites build their nests, researchers at Caltech have developed a framework to design new materials that mimic the fundamental rules hidden in nature's growth patterns. "We thought that by understanding how a termite contributes to the nest's fabrication, we could define simple rules for designing architected materials with unique mechanical properties," says Chiara Daraio, G. Bradford Jones Professor of Mechanical Engineering and Applied Physics; Investigator, Heritage Medical Research Institute. [Caltech story]

Tags: APhMS research highlights Chiara Daraio MCE

08-17-22

A new control algorithm for wind farms that alters how individual turbines are oriented into the wind promises to boost farms' overall efficiency and energy output by optimizing how they deal with their turbulent wake. "Individual turbines generate choppy air, or a wake, which hurts the performance of every turbine downwind of them," says John O. Dabiri, Centennial Professor of Aeronautics and Mechanical Engineering. "To cope with that, wind farm turbines are traditionally spaced as far apart as possible, which unfortunately takes up a lot of real estate." [Caltech story]

Tags: research highlights GALCIT MCE John Dabiri alumni Michael Howland

06-27-22

Techniques used in weather forecasting can be repurposed to provide individuals with a personalized assessment of their risk of exposure to COVID-19 or other viruses, according to new research published by Caltech scientists. The technique has the potential to be more effective and less intrusive than blanket lockdowns for combatting the spread of disease, says Tapio Schneider, Theodore Y. Wu Professor of Environmental Science and Engineering; Jet Propulsion Laboratory Senior Research Scientist. [Caltech story]

Tags: research highlights Chiara Daraio ESE Tapio Schneider Oliver Dunbar Lucas Böttcher Dmitry Burov Alfredo Garbuno-Inigo Gregory Wagner Sen Pei Raffaele Ferrari Jeffrey Shaman Jinlong Wu

06-09-22

A team of graduate students in Caltech's Advanced Mechanical Bipedal Experimental Robotics Lab (AMBER), led by Professor Aaron Ames, Bren Professor of Mechanical and Civil Engineering and Control and Dynamical Systems, is developing a new method of generating gaits for robotic assistive devices, which aims to guarantee stability and achieve more natural locomotion for different users. "If you're designing a trajectory for a robotic assistive device, a satisfactory gait should not only be stable but also feel natural," says Amy Li. [Caltech story]

Tags: research highlights MCE Yisong Yue Aaron Ames Maegan Tucker Kejun Li Rachel Gehlhar

06-07-22

By simulating earthquakes in a lab, Caltech engineers have provided strong experimental support for a form of earthquake propagation now thought responsible for the magnitude-9.0 earthquake that devastated the coast of Japan in 2011. "Our novel experimental approach has enabled us to look into the earthquake process up close, and to uncover key features of rupture propagation and friction evolution in rock gouge," says Vito Rubino, research scientist and lead author of the Nature paper. The Nature paper is titled "Intermittent lab earthquakes in dynamically weakening fault gouge." Rubino and his co-authors Nadia Lapusta, Lawrence A. Hanson, Jr., Professor of Mechanical Engineering and Geophysics, and Ares Rosakis, Theodore von Kármán Professor of Aeronautics and Mechanical Engineering, show that so-called "stable" or "creeping" faults are not actually immune to major ruptures after all, as previously suspected. [Caltech story]

Tags: research highlights GALCIT MCE Ares Rosakis Nadia Lapusta Vito Rubino

04-26-22

As part of the Science Journeys lecture series—designed to inspire scientific curiosity, especially among students in eighth grade and higher—graduate student Fernando Villafuerte discussed his path to Caltech and his research on batteries, including their role in sustainability solutions. Villafuerte works in the lab of Julia R. Greer, Ruben F. and Donna Mettler Professor of Materials Science, Mechanics and Medical Engineering; and Fletcher Jones Foundation Director of the Kavli Nanoscience Institute. His research focuses on a novel material known as a solid polymer electrolyte, which could potentially be used to create batteries that can store more energy than currently possible. [Caltech story]

Tags: APhMS research highlights MedE MCE Julia Greer Fernando Villafuerte