Isotropic Energy-Absorbing Metamaterial with Tensegrity-Inspired Architecture and Auxetic Behavior

Mechanical metamaterials exhibit significant potential for energy absorption applications through rational structural design. Negative Poisson's ratio (NPR) metamaterials have drawn particular attention due to their unique auxetic behavior, though their limited functionality restricts energy absorption capacity. This study develops a novel metamaterial combining NPR characteristics with tensegrity structure advantages to address traditional energy-absorbing materials' limitations in durability, self-recovery, and dynamic adjustability. By reconfiguring tensegrity modules into programmable units using spring combinations and implementing directional deformation constraints through rigid sliding rod and linear slider systems, the auxetic mechanism of NPR materials is integrated with tensegrity's programmable features. Experimental results demonstrate precise control of global auxetic response and overall stiffness through spring stiffness adjustment, with the elastic element combination providing self-recovery and fatigue resistance (only 0.40% energy absorption variation after 10000 compression cycles). For structural assembly, seven-cell and tetrahedral configurations achieve peak force reductions of ≈75.68 ± 1.22% and 91.18 ± 0.40% respectively, under impact, demonstrating assembly strategy scalability. This research breaks through traditional single-material metamaterial limitations by integrating tensegrity structures with NPR effects, establishing a new paradigm for developing intelligent protective materials with both tunable energy absorption characteristics and enhanced durability.