Tuning Quasi-Zero Stiffness in Additively Manufactured Kresling Structures via Silicone Encapsulation and Infill Design

Origami-inspired metamaterials enable
lightweight, reconfigurable structures with tunable
properties. The Kresling pattern is of particular interest for its
bistability and potential to realize quasi-zero stiffness (QZS)
behavior. In this work, Kresling specimens were fabricated
from thermoplastic poly(urethane) (TPU) using fused
filament fabrication (FFF) and modified by silicone
overcasting with poly(dimethylsiloxane) (PDMS) layers of
varying thickness and hardness. Uniaxial compression tests
showed that PDMS encapsulation increases overall stiffness
and load-bearing capacity but reduces the extent of the QZS
region. Infill density variations provided an additional means
of tuning: lower densities promoted broader QZS regimes,
while higher densities enhanced stiffness at the expense of
tunability. The results demonstrate that combining additive
manufacturing with silicone encapsulation and infill design
offers complementary strategies to program the mechanical
response of Kresling structures. This hybrid approach enables
the development of origami-based metamaterials tailored for
vibration isolation, damping, and soft robotic applications.