Structural instability is a hazard that leads to catastrophic failure and is generally avoided through special designs. A trend, however, has emerged over the past decades pointing to the harnessing of mechanisms with instability. Inspired by the snapping of a hair clip, we are finessing the unique characteristics of the lateral-torsional buckling of beams and the snap-through of pre-buckled dome-like thin-wall structures in a new field: the in-plane prestressed mechanism. Analyses reveal how the 2D-3D assembly of an in-plane prestressed actuator (IPA) is achieved and how the post-buckling energy landscape is pictured. Combining them with soft robotics, we show that the inclusion of a bistable IPA can enormously enhance the performance of an underwater fish robot as well as inspire a finger-like soft gripper.

翻译：结构不稳定性是导致灾难性失效的危险因素，通常需通过特殊设计加以避免。然而，过去几十年来出现了一种新趋势，即利用非稳定机构。受发夹弹开动作的启发，我们在一个新领域——面内预紧机构中，精妙地运用了梁的侧向扭转屈曲及预屈曲穹顶薄壁结构的突跳特性。分析揭示了面内预紧执行器（IPA）如何通过二维-三维组装实现，以及后屈曲能量景观的描绘过程。结合软体机器人技术，我们证明双稳态IPA的引入不仅能大幅提升水下仿鱼机器人的性能，还可启发指状软体夹持器的设计。