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A new, rubber-like film that can leap may one day help soft robots leap or lift

Anonymous — Thu, 19 Jan 2023 17:42:59 +0000

A new, rubber-like film that can leap may one day help soft robots leap or lift Anonymous (not verified) Thu, 01/19/2023 - 10:42

Engineers at �� have designed a new, rubber-like film that can leap high into the air like a grasshopper—all on its own and without needing outside intervention. Just heat it up and watch it jump! The researchers describe their achievement Jan. 18 in the journal Science Advances. They say that similar materials could one day help embody “soft robots” (those that don’t need gears or other hard components to move) to leap or lift.

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White Group applies controlled electric fields to liquid crystal elastomers for actuation and 3-D deformation

Anonymous — Thu, 18 Nov 2021 07:00:00 +0000

White Group applies controlled electric fields to liquid crystal elastomers for actuation and 3-D deformation Anonymous (not verified) Thu, 11/18/2021 - 00:00

Jonathan Raab

[video:https://youtu.be/XM_deixC8cc]
Liquid crystal elastomers undergoing directional actuation and deformation in response to electrical fields

Hayden Fowler, a graduate student in Gallogly Professor Timothy White’s Responsive and Programmable Materials Group, is the first author on a research paper published in Advanced Materials concerning the temperature-independent electrical actuation of liquid crystal elastomers (LCEs), which are soft, stimuli-responsive materials with potential applications in soft robotics, artificial muscles and more.

These LCEs are crosslinked polymer networks of rod-like units whose orientation enables the control of their formations, including directional actuation and 3-D deformations. Heat and light have traditionally been used as stimuli to control LCEs in laboratory environments, but are not viable in independent devices due to poor efficiency and responsiveness.

Fowler took inspiration from nature in tackling this research challenge.

“Many naturally occurring systems can efficiently and effectively convert input energy into mechanical response,” Fowler said. “For example, the human hand integrates sensing, structure and actuation to accomplish high force as well as gentle dexterity. However, it is an ongoing challenge to incorporate all these capabilities into man-made or robotic systems.”

Fowler, White and their partners sought to apply a controlled electric field to manipulate the LCEs. They applied electrodes to opposite sides of an LCE formation. Because LCEs can be aligned and directed, they expanded in “softer” directions with response times much faster than traditional heat and light methods.

“I have really enjoyed working with Hayden thus far on their research,” said White. “They did a great job to drive this difficult project to completion. Hayden worked closely with Dr. Philipp Rothemund of the Keplinger group to quickly come up a learning curve in this new area of research for my group. I’m excited to see where Hayden takes their research as they finalize their PhD.”

Professor Christoph Keplinger and his postdoctoral associate Philipp Rothemund of the Max Planck Institute for Intelligent Systems in Stuttgart, Germany provided essential contributions to the research.

“Keplinger and Rothemund were instrumental in bringing me up the learning curve on this project, and Rothemund contributed his knowledge of modeling these types of actuators to theoretically predict their performance based purely on the physical, measurable properties of the materials,” Fowler said.

White is an expert in synthesis and alignment of LCE materials, Fowler said, noting his knowledge gained at the Air Force Research Lab helped push the project forward. They credited White’s group and the Department of Chemical and Biological Engineering as possessing unique strengths in processing and characterizing the materials used in the research. White’s group was also prepared to test and evaluate performance in materials actuator applications.

“One of my goals is to improve the materials chemistry, and therefore the performance, of these actuators,” Fowler said. “I am interested in probing the effects of network structure, processing, phase behavior and monomer content on the properties of the material that affect their performance as electromechanical actuators. These include but are not limited to the material’s recoverability, dielectric properties and stiffness.”

Hayden Fowler, a graduate student in Gallogly Professor Timothy White’s Responsive and Programmable Materials Group, is the first author on a research paper published in Advanced Materials concerning the temperature-independent electrical actuation of liquid crystal elastomers (LCEs), which are soft, stimuli-responsive materials with potential applications in soft robotics, artificial muscles and more.

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Welcoming Professors Michael McGehee and Timothy White

Anonymous — Wed, 13 Jun 2018 17:37:32 +0000

Welcoming Professors Michael McGehee and Timothy White Anonymous (not verified) Wed, 06/13/2018 - 11:37

Professors Michael McGehee and Timothy White.

The department is pleased to welcome two new professors to the faculty: Michael D. McGehee and Timothy J. White.

McGehee joins the department from Stanford University, where he has served on the materials science and engineering faculty since 2000. He earned a bachelor’s degree in physics from Princeton and a PhD in materials science from the University of California, Santa Barbara.

McGehee’s research focuses on perovskite solar cells and dynamic windows with adjustable tinting, and his group aims to develop technology that provides humanity with clean energy and solves environmental problems.

A highly-cited and impactful researcher, McGehee is a fellow of the Materials Research Society and the recipient of the MRS Outstanding Young Investigator Award. His former students have started a dozen companies and won the Forbes “30 under 30” recognition five times.

A fellow of the Renewable & Sustainable Energy Institute and Materials Science and Engineering Program, McGehee is based in the Sustainability, Energy & Environment Community on East Campus.

He joined the department this spring and began conducting research in Boulder this summer. He will begin teaching courses related to solar energy and materials engineering in January.

“Professor McGehee is a highly recognized world leader in solar cells and has been at the forefront of the revolution of perovskite solar cells,” said department Chair Charles Musgrave. “Hiring Mike is a tremendous achievement for our department and CU and will further establish CU as a leading institution for materials science.”

White, appointed as the first Gallogly Professor in the College of Engineering and Applied Science, joins �� from the Air Force Research Laboratory, where he has served in several roles since joining the lab as a postdoctoral researcher in 2006. Most recently, White served as the lead of the 30-member Structured Optical Materials and Processes Team, focusing on technology development and maturation of stimuli-responsive materials and their integration in aerospace systems.

White concurrently held appointments as a research faculty member at the University of Dayton and an adjunct faculty member at Case Western Reserve University.

White’s research interests have generally focused on stimuli-responsive effects in soft materials. Initial research directions at �� will build upon and extend from his research activities at AFRL relating to the directed self-assembly of liquid crystalline elastomers, networks, and gels and realizing reconfigurable optical properties in low-molar mass liquid crystal/polymer composites. White intends to extend his research in exploiting the dynamic character of these materials in the health sciences and in energy applications.

He has published more than 130 papers in peer-reviewed journals and has more than 10 patents awarded or pending.

An internationally recognized researcher, he earned the 2016 Outstanding Young Investigator Award from the Materials Research Society and Early Career Awards from SPIE and the U.S. Air Force in 2013 and 2012, respectively.

White earned his bachelor’s degree in chemistry from Central College (where he was an NCAA All-American in golf) and master’s and doctoral degrees in chemical and biochemical engineering from the University of Iowa.

White is rostered in Chemical & Biological Engineering and Materials Science & Engineering and will join the faculty on July 1.

“Tim has been on an absolutely meteoric trajectory during his relatively short career, and hiring him is a major coup for CU Chemical and Biological Engineering and Materials Science & Engineering, further cementing our leadership in soft materials,” Musgrave said.

“With the hiring of Mike McGehee and Tim White, Chemical and Biological Engineering is now home to four winners of the highly prestigious MRS Outstanding Young Investigator Award – a huge testament to our strength in materials science.”

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