Dynamic response and energy absorption of spider orb-web in prey capture at oblique impact angle

The spider orb-web is a prime candidate for biomimetic net design due to its exceptional energy absorption properties. Unlike most artificial cable nets, it is composed of two types of silk with vastly different mechanical properties, which may help mitigate overall damage during impact. This study investigates the dynamic response and energy absorption characteristics of spider orb-webs under oblique impact angles, an aspect not previously explored. A finite element model of an orb-web subjected to impact by a spherical projectile at varying incident angles, distances from the web centre, and velocities was developed. The material properties of dragline and spiral silk in the model correspond to those produced by Araneus diadematus, while the projectile's size and mass mimic those of the spider's common large prey. Simulation results indicate that the orb-web is optimized for prey capture across a wide range of impact angles. Furthermore, it was demonstrated that the web is well-adapted for efficient repair and effective prey capture by localizing damage and minimizing structural compromise. Damage is confined to a limited region, primarily through the sacrificial failure of radial threads near the impact point. Energy absorption increases with incident angle and impact velocity but decreases with greater distances from the web centre.