ENERGY ABSORPTION CHARACTERISTICS OF A NEW AUXETIC HONEYCOMB AND ITS APPLICATION TO A BUMPER

A novel honeycomb structure with arc walls inserted into the concave hexagonal honeycomb cells (RHWAI) is proposed. Parameter analysis is conducted through numerical calculations, revealing that as the cell angle increases, the peak force initially decreases and subsequently increases, with a minimum peak force observed at a cell angle of 60 degrees, and the plateau force gradually decreases, while energy absorption initially decreases and then fluctuates within a certain range. As the wall thickness increases, the peak force, plateau force, and energy absorption also increase continuously. With increasing of parameter h 1 , the peak force decreases continuously, the plateau force first increases and then decreases, and the energy absorption gradually decreases. After that, the newly designed honeycomb structure is applied to the bumper absorbing box and is compared with traditional reentrant honeycomb-filled and unfilled energy-absorbing boxes. The results indicate that after filling with the RHWAI honeycomb, the intrusive displacement of the bumper is reduced, and its energy absorption capacity is enhanced. Notably, the bumper filled with the RHWAI honeycomb exhibits a total energy absorption capacity that exceeds that of an unfilled honeycomb box by over 300%. The RHWAI honeycomb demonstrates the highest specific energy absorption (SEA) and strongest energy absorption capacity. A thorough analysis of the deformation and performance of energy-absorbing boxes at different impact velocities shows that while the energy absorption of the bumper does increase with higher impact velocities, the magnitude of this increase remains relatively modest. The design of the trigger and the honeycomb filling of the energy absorbing box improve the protection performance of the energy absorbing box. These insightful research findings offer novel perspectives for enhancing impact protection.