Our research in the Laboratory of Engineered Materials and Structures (LEMS) is directed towards designing and developing advanced engineered structures through the creation of novel materials systems, e.g., mechanical metamaterials, phononic crystals, and composites. These materials offer an enhanced degree of freedom in controlling their mechanical responses under harsh environments, such as impact and vibrations. Based on the understanding of their mechanics, we aim to enhance safety, performance, and sustainability of next-generation aerospace, mechanical, and biomechanical structures. Here we list a few exemplary projects.
We investigate unique wave dynamics in mechanical metamaterials. The design of these metamaterials is often inspired by origami, biological systems, and fundamental physical notions. Their fabrication is assisted by additive manufacturing techniques. By using these metamaterials, we aim at demonstrating various types of linear/nonlinear waveforms unprecedented in conventional systems. Such wave dynamics can be potentially used for engineering applications, such as vibration filtering, impact mitigation, and energy harvesting. Project sponsors: NSF-CAREER, NSF-DCSD, and Washington Research Foundation
Videoclip on origami-based metamaterial research: Youtube Link
(Top left) 1D origami chain for generating rarefaction waves. (Right) Volumetric origami cells for deployable structures and their prototype enabled via additive manufacturing in collaboration with Prof. Kunimine. (Bottem left) 3D printed lattice for manipulating wave propagation.
Inspired by topological insulators in condensed matter physics, we design 1D to 3D architectures of topological metamaterials. These systems enable controllable localization and guiding of stress waves with defect-immune and robust characteristics. The goal of this project is to investigate and demonstrate this new design paradigm with the help of analytical, numerical, and experimental techniques. We place emphasis on the practical design of such topological platforms, possibly with tunable nature. Project sponsor: NSF-EFRI
(Top left) 1D realization of tunable topological lattice. (Top right) 2D platform of topological waveguide based on a locally resonant bolted plate. (Bottom) 3D exploration of topological waveguides.
Coral reefs are disappearing at a rapid rate around the world. We 3D print scaffolds to guide coral growth and look into new techniques to measure how well the corals grow. Collaborating with PI Yang's group are Judith Klein-Seetharaman at the Colorado School of Mines, Hollie Putnam of the University of Rhode Island, Lenore Cowen at Tufts University and Nastassja Lewinski at Virginia Commonwealth University. Project sponsor: NSF-HDR:DIRSE-IL
Media Coverage: UW News
(A) Complexity of the coral holobiont. (B) The HDR stage: shining light on open questions in coral biology and potential application areas with the synthetic coral convergence theme (Image from the team's NSF proposal).
We explore the design of non-conventional composite structures, such as discontinuous fiber composites and self-deploying composite structures (in collaboration with Professor Marco Salviato's team at the University of Washington), and shallow bi-angle, thin-ply wings (in collaboration with Professor Steve Tsai at Stanford University). Project sponsors: FAA-AMTAS, JCATI, and Boeing
(Top) Molding and fabrication process of non-conventional wing structures. (Bottom left) Discontinous fiber composites and their notch-insensitive fracture behavior. (Bottom right) Deployable composite prototype based Tachi-Miura polyhedron.