News & Events

Headlines

Wennberg Lab Shows How Wildfire Smoke Increases Ozone Pollution

12-09-21

Using data gathered from a specially equipped jet that spent a month flying through and studying wildfire plumes, scientists have a better understanding now of how wildfire smoke impacts air quality. "Of course it is well known that wildfires lower air quality. But it's important to understand the chemical and physical mechanisms by which they do so that we can more effectively forecast how individual fires will impact the communities downwind of them," says Paul O. Wennberg, R. Stanton Avery Professor of Atmospheric Chemistry and Environmental Science and Engineering; Executive Officer for Environmental Science and Engineering; Director, Ronald and Maxine Linde Center for Global Environmental Science. [Caltech story]

Tags: research highlights ESE Paul Wennberg Lu Xu

Gunnarson and Dabiri Teach AI to Navigate Ocean with Minimal Energy

12-09-21

Engineers at Caltech, ETH Zurich, and Harvard are developing an artificial intelligence (AI) that will allow autonomous drones to use ocean currents to aid their navigation, rather than fighting their way through them. "When we want robots to explore the deep ocean, especially in swarms, it's almost impossible to control them with a joystick from 20,000 feet away at the surface. We also can't feed them data about the local ocean currents they need to navigate because we can't detect them from the surface. Instead, at a certain point we need ocean-borne drones to be able to make decisions about how to move for themselves," says John Dabiri, Centennial Professor of Aeronautics and Mechanical Engineering. [Caltech story]

Tags: research highlights GALCIT MCE John Dabiri Peter Gunnarson

Controlling Light with a Material Three Atoms Thick

10-22-21

Scientists can control light more precisely than ever with a material only three atoms thick and constructed from so-called black phosphorous. In the lab of 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, three layers of phosphorous atoms were used to create a material for polarizing light that is tunable, precise, and extremely thin. Black phosphorous tech could revolutionize telecommunications by vastly improving light signals sent through fiber-optic cables. The technology could also open the door to a light-based replacement for Wi-Fi, something researchers in the field refer to as Li-Fi. "Increasingly, we're going to be looking at light-wave communications in free space," Atwater says. "Lighting like this very cool-looking lamp above my desk doesn't carry any communication signal. It just provides light. But there's no reason that you couldn't sit in a future Starbucks and have your laptop taking a light signal for its wireless communication rather than a radio signal. It's not quite here yet, but when it gets here, it will be at least a hundred times faster than Wi-Fi." [Caltech story]

Tags: APhMS research highlights Harry Atwater KNI

LEONARDO, the Bipedal Robot, Can Ride a Skateboard and Walk a Slackline

10-06-21

Researchers have built a bipedal robot that combines walking with flying to create a new type of locomotion, making it exceptionally nimble and capable of complex movements. "We drew inspiration from nature. Think about the way birds are able to flap and hop to navigate telephone lines," says Soon-Jo Chung, Bren Professor of Aerospace and Control and Dynamical Systems; Jet Propulsion Laboratory Research Scientist. "A complex yet intriguing behavior happens as birds move between walking and flying. We wanted to understand and learn from that." A paper titled "A bipedal walking robot that can fly, slackline, and skateboard" about the LEO robot was published online on October 6 and was featured on the October 2021 cover of Science Robotics. [Caltech story]

Tags: research highlights CMS Soon-Jo Chung Elena-Sorina Lupu Kyunam Kim Patrick Spieler Alireza Ramezani

The Science of Underground Kingdoms

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

Nano-Architected Material Resists Impact Better Than Kevlar

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

New Algorithm Helps Autonomous Vehicles Find Themselves, Summer or Winter

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

Harnessing Sound for Health: A Conversation with Tim Colonius

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

Recording Brain Activity with Laser Light

06-07-21

Lihong Wang, Bren Professor of Medical Engineering and Electrical Engineering, has demonstrated for the first time a new technology for imaging the human brain using laser light and ultrasonic sound waves. The technology, known as photoacoustic computerized tomography, or PACT, has been developed as a method for imaging tissues and organs. Now, Wang has made further improvements to the technology that make it so precise and sensitive that it can detect even minute changes in the amount of blood traveling through very tiny blood vessels as well as the oxygenation level of that blood. [Caltech story]

Tags: EE research highlights MedE Lihong Wang

How Do You Test a Helicopter Bound for Mars?

04-29-21

Caltech grad students helped JPL build a custom wind tunnel in a vacuum chamber for the Mars Ingenuity helicopter. The Ingenuity helicopter may be the first vehicle ever to fly on Mars, but Mars was not the first place it has ever flown. Before packaging it up and blasting it to the Red Planet, engineers at JPL gave the helicopter a trial run in a special wind tunnel. The fan array was designed and built by JPL engineers with input from Chris Dougherty and Marcel Veismann, who are currently working with Morteza Gharib, Hans W. Liepmann Professor of Aeronautics and Bioinspired Engineering and Booth-Kresa Leadership Chair of Caltech's Center for Autonomous Systems and Technologies (CAST). Jason Rabinovitch, who was a mechanical engineer at JPL working on testing the helicopter, reached out to the CAST team in 2017. "I'd earned my PhD at GALCIT, so I was aware of CAST and its facilities," says Rabinovitch. [Caltech story]

Tags: research highlights GALCIT Morteza Gharib Jason Rabinovitch Marcel Veismann Chris Dougherty