TY - JOUR AU - Jiang, Xiaochun AU - Wang, Zhengjin AU - Sun, Danqi AU - Lu, Tongqing AU - Wang, Tiejun PY - 2021 M3 - Original Research TI - Toughening Mechanism of Unidirectional Stretchable Composite JO - Frontiers in Robotics and AI UR - https://www.frontiersin.org/articles/10.3389/frobt.2021.673307 VL - 8 SN - 2296-9144 N2 - Composite materials have been long developed to improve the mechanical properties such as strength and toughness. Most composites are non-stretchable which hinders the applications in soft robotics. Recent papers have reported a new design of unidirectional soft composite with superior stretchability and toughness. This paper presents an analytical model to study the toughening mechanism of such composite. We use the Gent model to characterize the large deformation of the hard phase and soft phase of the composite. We analyze how the stress transfer between phases deconcentrates the stress at the crack tip and enhances the toughness. We identify two types of failure modes: rupture of hard phase and interfacial debonding. We calculate the average toughness of the composite with different physical and geometric parameters. The experimental results in literature agree with our theoretical predictions very well. ER -