Don’t miss Shu Yang’s seminar, “Snapping of Liquid Crystal Elastomer Looped Fibers and Knots for Diverse Motions and Sustainability”, on October 9 at 3pm in Maryland hall room 110.
Abstract: Snapping of Liquid Crystal Elastomer Looped Fibers and Knots for Diverse Motions and Sustainability
Snapping instability is common in nature as seen in Venus flytrap and hummingbird to catch insects mid-flight where the animals and plants use this mechanism to store the elastic energy and release it as kinetic energy for rapid motions. Here, I will discuss how we explore spontaneous snap-through instabilities in looped fibers and knots made from liquid crystal elastomers (LCE) upon contact with a hot surface. When LCE fibers are connected into lobed loops, where each fiber is geometrically constrained by the neighboring ones, they demonstrate autonomous, self-regulated, and repeated synchronization. By adding a rigid bead on the fiber, we can fine-tune the actuation direction and speed, demonstrating various gait-like locomotion patterns using the loops as the soft robot’s legs. By exploiting the knot topology and materials elasticity, I will discuss our effort to program the stored elastic energy within the knots, demonstrating ultrafast, ultrahigh leaping behaviors with variable flying patterns. Lastly, I will discuss their potential applications for seed dispersals and self-burial seeding for sustainability.
Bio: Shu Yang
Shu Yang is a Joseph Bordogna Professor of Engineering and Applied Science and Department Chair of Materials Science & Engineering at University of Pennsylvania (Penn). Her group is interested in synthesis, fabrication, assembly of soft and hybrid materials and their dynamic tuning, and the use of geometry and topology to create highly flexible, super-conformable, shape changing and energy efficient materials. Yang received her B.S. degree from Fudan University, and Ph. D. degree from Cornell University. She was recognized by American Chemical Society (ACS)’s Langmuir lectureship, The International Liquid Crystal Society Mid-Career Award (LG), and Inventor of the Year at Penn. She is a Fellow of American Association for the Advancement of Science (AAAS), Materials Research Society (MRS), ACS, American Physical Society (APS), and National Academy of Inventors (NAI).