News & Events

08-24-21

A team led by the laboratory of Jose Andrade, George W. Housner Professor of Civil and Mechanical Engineering; Cecil and Sally Drinkward Leadership Chair, Department of Mechanical and Civil Engineering; Executive Officer for Mechanical and Civil Engineering, studied the digging habits of ants and uncovered the mechanisms guiding them. Before beginning this research, Andrade had a big question he wanted to answer: Do ants "know" how to dig tunnels, or are they just blindly digging? "I got inspired by these exhumed ant nests where they pour plastic or molten metal into them and you see these vast tunnel systems that are incredibly impressive," Andrade says. He enlisted the help of Joe Parker, Assistant Professor of Biology and Biological Engineering, whose research focuses on ants and their ecological relationships with other species. "What Jose and his team needed was somebody who works with ants and understands the adaptive, collective behaviors of these social insects to give them some context for what they were doing," Parker says. [Caltech story]

Tags: research highlights MCE Jose Andrade Joe Parker Robert Buarque de Macedo Edward Andò Shilpa Joy Gioacchino Viggiani Raj Kumar Pal

06-25-21

Julia R. Greer, Ruben F. and Donna Mettler Professor of Materials Science, Mechanics and Medical Engineering; Fletcher Jones Foundation Director of the Kavli Nanoscience Institute, has developed a nano-architected material made from tiny carbon struts that is, pound for pound, more effective at stopping a projectile than Kevlar, a material commonly used in personal protective gear. "The knowledge from this work could provide design principles for ultra-lightweight impact resistant materials for use in efficient armor materials, protective coatings, and blast-resistant shields desirable in defense and space applications," says Greer. [Caltech story]

Tags: APhMS research highlights MedE MCE Julia Greer KNI

06-24-21

Without GPS, autonomous systems get lost easily. Now a new algorithm developed at Caltech allows autonomous systems to recognize where they are simply by looking at the terrain around them—and for the first time, the technology works regardless of seasonal changes to that terrain. The general process, known as visual terrain-relative navigation (VTRN), was first developed in the 1960s. By comparing nearby terrain to high-resolution satellite images, autonomous systems can locate themselves. The problem is that, in order for it to work, the current generation of VTRN requires that the terrain it is looking at closely matches the images in its database. To overcome this challenge, Anthony Fragoso, Lecturer in Aerospace; Staff Scientist, Connor Lee, Graduate student in Aerospace, Austin McCoy, Undergraduate, and Soon-Jo Chung, Bren Professor of Aerospace and Control and Dynamical Systems and research scientist at JPL, turned to deep learning and artificial intelligence (AI) to remove seasonal content that hinders current VTRN systems. [Caltech story]

Tags: research highlights GALCIT MCE CMS Soon-Jo Chung Anthony Fragoso Connor Lee Austin McCoy

06-18-21

When a person develops a kidney stone or a gall stone—hard accumulations of minerals and other compounds created by the body—they can experience a great deal of pain and discomfort. Lithotripsy is the practice of breaking gall or kidney stones into small pieces within the body using shockwaves produced by a machine called a lithotripter. A new form of lithotripsy has been under development with the help of Tim Colonius, Frank and Ora Lee Marble Professor of Mechanical Engineering. [Caltech story]

Tags: research highlights MCE Tim Colonius

04-05-21

A good way to find out what a cell is doing—whether it is growing out of control as in cancers, or is under the control of an invading virus, or is simply going about the routine business of a healthy cell—is to look at its gene expression. Lior Pachter, Bren Professor of Computational Biology and Computing and Mathematical Sciences, has developed a complex software tool that enables the processing of large sets of genomic data in about 30 minutes, using the computing power of an average laptop. Like a Swiss Army knife, the tool can be used in myriad ways for different biological needs, and will help ensure the reproducibility of scientific studies. "The interdisciplinarity of our team was crucial to conceiving of and executing this project," says Pachter. "There are people in the lab who are computer scientists, biologists, engineers. Sina Booeshaghi is in the mechanical engineering department and brings the perspective of his design background and engineering." [Caltech story]

Tags: research highlights MCE CMS Lior Pachter Sina Booeshaghi

03-12-21

Nadia Lapusta, Lawrence A. Hanson, Jr., Professor of Mechanical Engineering and Geophysics, and graduate student Valère Lambert, seek to explain the size of the forces acting on "mature faults"—long-lived faults along major plate boundaries like the San Andreas Fault in California—in an effort to better understand the physics that drive the major earthquakes that occur along them. Understanding the physics that govern major earthquakes on different types of faults will help generate more accurate forecasts for earthquake threats. "We have a lot of data from large earthquakes along subduction zones, but the last really major earthquakes along the San Andreas were the magnitude-7.9 Fort Tejon quake in 1857 and the magnitude-7.9 San Francisco Earthquake in 1906, both of them before the age of modern seismic networks," Lapusta says. [Nature article] [Caltech story]

Tags: research highlights MCE Nadia Lapusta Valère Lambert

02-16-21

As astronauts walk across the moon, land spacecraft on its surface, drive lunar rovers around, or complete other astronaut tasks, they kick up the dust, and that is a problem because it can cause premature wear on mechanical parts, damage to seals, and may pose a health risk for the people breathing it in. "The sun is shining directly on these particles and giving them an electric charge," says third-year Caltech undergraduate student Luis Pabon. "This causes it to stick to the astronaut's suit or to any sensors or cameras that you put out on the moon." The Caltech team's invention, named Habitat Orientable & Modular Electrodynamic Shield (HOMES), tackles the problem of moon dust entering a potential lunar habitat and wreaking havoc within. [Caltech story]

Tags: research highlights GALCIT MCE Luis Pabon

12-07-20

Crystals are usually good at conducting heat. By definition, their atomic structure is highly organized, which allows atomic vibrations—heat—to flow through them as a wave. Austin Minnich, Professor of Mechanical Engineering and Applied Physics, has discovered why a perfect crystal is not good at conducting heat, although it seemingly should be. "We have found that quantum mechanical effects can play a huge role in setting the thermal transport properties of materials even under familiar conditions like room temperature," says Austin Minnich. [Caltech story]

Tags: APhMS research highlights MCE KNI Austin Minnich

11-18-20

Methods that were originally created to help robots to walk and autonomous cars to drive safely can also help epidemiologists predict the spread of the COVID-19 pandemic. Aaron Ames, Bren Professor of Mechanical and Civil Engineering and Control and Dynamical Systems, and colleagues took these tools and applied them to the development of an epidemiological methodology that accounts for human interventions (like mask mandates and stay-at-home orders). By utilizing the U.S. COVID-19 data from March through May, they were able to predict the infection wave during the summer to high accuracy. "This is the greatest health challenge to face our society in a generation at least. We all need to pitch in and help in any way we can," Ames says. [Caltech story]

Tags: research highlights MCE CMS IST Aaron Ames CDS Andrew Singletary

09-03-20

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]

Tags: research highlights GALCIT MCE Ares Rosakis