Multistable twist metastructures with enhanced collapsibility and multidimensional programmability

Abstract

Multistable metastructures with compression-twist coupling offer promising applications in reusable protective devices, deployable structures and reconfigurable robotics. However, existing designs based on either Kresling origami or truss-based mechanisms, suffer from limited deformability, due to the accumulation of bending deformation in creases or trusses. Herein, we propose a novel multistable twist metastructure by integrating hinged beams with Kresling-inspired trusses. A two-step procedure, combining 3D printing and interlocking assembling, is utilized to fabricate the multistable twist samples. This multistable twist mechanism leverages the elastic instability and shape reconfiguration of hinged beams, enabling transitions between stable configurations with minimal bending in the trusses. This approach achieves exceptional collapsibility with a reusable maximum allowable compression up to 80 % of the structural height. Additionally, the compression-twist coupling of trusses protects hinged beams from severe tensile damage. Furthermore, our strategy offers multidimensional programmability. Geometric design tailors configuration stability (i.e., multi/bistability, monostability, monotonicity), while arraying method controls deformation modes. This culminates in the realization of customized functions of impact resistance and vibration mitigation. Specially, by incorporating trusses, negative stiffness with loop hysteresis can be programmed to enhance energy dissipation, which facilitates to damping the impact and vibration. Experimental tests confirm the compatibility of excellent collapsibility, programmability and multifunctionality. This finding underscores the potential of such multistable metastructure with compression-twist coupling for designing next-generation reusable multifunctional devices.