Origami Design Enabled by Active Polymers

Origami design principles allow creating complex three-dimensional structures from a single sheet of paper through folding. The simplicity of this setup renders origami design an appealing concept across a broad range of length scales. However, in addition to carefully designing the crease patterns, the folding process requires a great level of dexterity, if done manually, or sophisticated robotics. The challenges of the folding process increase as the length scale decreases. Utilizing active materials in origami design is an appealing approach, in particular at small length scales.

In this talk, we present an overview of material systems and design approaches suitable to create and actuate folds in initially flat substrates. Typically, these material systems contain active material components which either deform and develop actuation forces upon external stimuli or change their stiffness on demand, triggering deformations due to pre-strain in other material components. Here, we focus on active polymers as they allow tailoring the material system to a particular application. A broad range of stimuli and actuation mechanisms are available, such as thermal, chemical, and optical. Further, the properties of the polymer can be radically changed after the folding sequence is completed, e.g. the stiffness of the material components can be increased.

In the design of origami structures with active materials, the specific characteristics of deformation and actuation force generation, the temporal and spatial control of the stimuli, and the mechanical response of the entire structure need to be carefully considered. To this, end we present a modeling framework which models various actuation mechanisms via generalized eigenstrains and accounts for finite strains and large displacements. To determine the crease patterns, a topology optimization approach is adopted. The potential of utilizing active materials for the design of origami structures is demonstrated with selected examples, which are studied both experimentally and numerically.

About Kurt Maute

Kurt Maute is the Joseph Negler Professor of Aerospace Engineering Sciences and Associate Dean for Reach at the University of Colorado, Boulder. His research interests include structural topology and shape optimization, multidisciplinary optimization, optimization of aeroelastic systems, adaptive discretization methods in structural optimization, and optimization of materially nonlinear structures.

See website: http://www.colorado.edu/aerospacestructures/people/kurt-maute