Abstract
In this talk, I will first introduce our recent work on origami milli-spinner device for treatment of Acute Ischemic Stroke, a blockage or interruption of blood flow within a cervical or cerebral artery that can result in irreversible brain injury or impaired neuronal function in ischemic brain tissue. The milli-spinner spinner is demonstrated to effectively and significantly reduces the size of blood clots for fast and complete clot removal. The milli-spinner is based on the integrated suction and centrifuge mechanisms that separate red blood cells from the clot for clot volume reduction to only less than 10% of the initial volume. I will present the in vitro and in vivo test of the spinners in pig studies. The outcome is compared with the current state-of-the-art aspiration and stent retriever thrombectomy devices.
For the second part of my talk, the concept of hexagonal ring origami folding mechanism will be introduced as a strategy for deployable/foldable structures for space applications. The hexagonal rings can tessellate 2D/3D surfaces and each ring can snap to its stable folded configuration with only 10.6% of the initial area. We combine a multi-segment Kirchhoff rod model, finite element simulations, and experiments to investigate the snap-folding of the hexagonal ring with slight geometric modification and residual strain for easy folding of the ring to facilitate the design and actuation of hexagonal ring origami assemblies for functional foldable structures with extreme packing ratio. Then, I will introduce the curved-sided hexagonal ring, which can magically lead to four equilibrium states, namely the star hexagram, the daisy hexagram, the 3-loop line, and the 3-loop “8” configurations when the ring has carefully designed natural curvature. The transitions between the four states will be presented.
About the Speaker
Renee Zhao is an Assistant Professor of Mechanical Engineering, a Terman faculty fellow, and a Gabilan faculty fellow at Stanford University. Renee received her PhD degree in Solid Mechanics from Brown University in 2016. Before Renee joined Stanford, she was an Assistant Professor at The Ohio State University and a postdoc at MIT. Renee’s research concerns the development of stimuli-responsive soft composites and shape morphing mechanisms for multifunctional robotic systems. Renee is a recipient of the NSF Career Award, AFOSR YIP Award, ARO Early Career Program (ECP) Award, ASME Journal of Applied Mechanics award (2021), and the Eshelby Mechanics Award for Young Faculty.
Host: Professor Sam Tawfick
