WEST BETHESDA, Md. —
Most people are familiar with the Japanese art of origami, folding paper into various three-dimensional shapes, most commonly animals, but what about using it for structural engineering purposes? Dr. Evgueni Filipov, assistant professor in the Department of Civil and Environmental Engineering at the University of Michigan, is doing just that. In a lecture at Naval Surface Warfare Center, Carderock Division on Aug. 21, Filipov discussed his thoughts on the matter.
“Can we take something, make it compact, and then deploy it? Can we have something that’s prefabricated? Or something that requires self-assembly, something that starts out flat and then we get it into a 3D shape?” Filipov said. “When we start getting into the smaller-scale projects where origami can be useful, some of the work we’re doing is self-folding, like stints.”
Filipov’s research interests are focused on the underlying mechanics of origami to inspire deployable, reconfigurable and adaptable 3D structures. He claims that these mechanics are used to improve stiffness, functionality and the manufacturing of the folded systems.
“Within origami, there are three main research topics: theory and analysis, where you put the fold lines and how do you decide how to fold these structures; system design, used when you want to have a specific shape and how to fold through complex geometry; and materials and fabrication,” Filipov said. “Flexibility, rigidity and where fold-lines can be placed are important to consider when wanting to use origami for systems.”
By designing the geometry and mechanical properties of the origami, it is possible to create engineering systems ranging from micro-robots and novel metamaterials to large-scale adaptable architecture, according to Filipov. An origami design with a hyperbolic paraboloid geometry is used to achieve bi-stable and multi-stable characteristics that can aid in actuation. Filipov presented cellular and tubular origami, which can be used for stiff, large structures. Using curved creases in an origami design, he also showed a broad range of possible geometric designs that possess highly anisotropic properties and tunable stiffness.
“There is a very popular pattern called the Miura-ori that is developable, meaning it can be folded from a flat sheet. The application of space, because it can be created and go back to being flat and compact. The last is rigid foldability, once it has been folded the flat parts do not bend and here we can also add thickness in the basic design,” Filipov said. “These patterns have a one-degree of freedom kinematics, there is one specific way you can fold and unfold these.”
Filipov has been working with graduate students at the University of Michigan and program officer Paul Hess from the Office of Naval Research on his most recent project and its applicability to the Navy. More information about it can be found here: http://www.efilipov.com.