Jambulingam Padmapooja, Wang Dan, Le Ferrand Hortense
School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore.
Institute of High Performance Computing (IHPC), Agency for Science, Technology and Research (A*STAR), 1 Fusionopolis Way, #16-16 Connexis, Singapore, 138632, Singapore.
Sci Rep. 2025 Apr 22;15(1):13900. doi: 10.1038/s41598-025-97914-3.
Multistability is the phenomenon by which a material changes shape quickly between multiple stable states upon the application of an external trigger. Typically, fibre-reinforced composites assembled into laminates with [± 45°] or [0°/90°] layup exhibit bistability. These materials have commonly rectangular geometries, restricting their integration into more complex systems such as soft robotic actuators or biomimetic devices. One approach to increase the number of stable states is to locally vary the fibre orientation while tailoring the geometry of the bilayer laminate. This strategy is explored here using flower-shaped laminates as proof-of-concept. The dimensions of the flower's petals as well as the local fibres' orientations are varied using local and global coordinates systems. The morphing and the number of stable states are studied using the Finite Element Method (FEM) under various mechanical loading methods. The results demonstrate that multistability can be obtained by varying the geometry and the local fibre orientations. Generally, larger width-to-length ratios for the petals are also better for generating stable states. The simulated results are compared and discussed and could be used as a benchmark for exploring such systems in experiments or for designing even more complex multistable structures to meet the needs of soft robotics or other applications.
多稳定性是指材料在外部触发作用下能在多个稳定状态之间快速改变形状的现象。通常，组装成具有[± 45°]或[0°/90°]铺层的层压板的纤维增强复合材料表现出双稳态。这些材料通常具有矩形几何形状，限制了它们集成到更复杂的系统中，如软机器人致动器或仿生装置。增加稳定状态数量的一种方法是在定制双层层压板几何形状的同时局部改变纤维取向。本文以花形层压板为例探索了这一策略。利用局部和全局坐标系改变花瓣的尺寸以及局部纤维的取向。在各种机械加载方法下，使用有限元方法（FEM）研究变形和稳定状态的数量。结果表明，通过改变几何形状和局部纤维取向可以获得多稳定性。一般来说，花瓣较大的宽长比也更有利于产生稳定状态。对模拟结果进行了比较和讨论，可作为在实验中探索此类系统或设计更复杂的多稳定结构以满足软机器人或其他应用需求的基准。
