Smart Soft Composite: An Integrated 3D Soft Morphing Structure Using Bend-twist Coupling of Anisotropic Materials

Traditionally, hard or high-stiffness materials are used to achieve morphing but only with limited magnitudes of deformation. Soft and low-stiffness materials are required to implement soft morphing with large deformations. In this paper, a novel concept for soft morphing structures that makes use of smart soft composites (SSC) is introduced. These materials have the following characteristics: 1) Large deformations from smart actuators and soft anisotropic materials embedded in a soft matrix material, 2) Utilization of the coupling effect for in-plane/bending/twisting deformations of the morphing structure to achieve complex morphed shapes, 3) Semi-automated three-dimensional (3D) fabrication via 3D printing processes. Classical lamination theory is used to express in-plane deformation, out-of-plane deformation, and twisting and coupling of these deformations. 3D-printed-scaffold and/or weaving methods can be used to fabricate anisotropic materials for SSCs. An integrated SSC in a cantilever shape is fabricated using SMA (Shape memory alloy)/ABS/PDMS and tested as an example to show large deformation with bend/twist coupling effect.