SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, United Kingdom.
Humboldt Centre for Nano- and Biophotonics, Department of Chemistry, University of Cologne, Cologne, Germany.
Elife. 2024 Jul 23;12:RP87746. doi: 10.7554/eLife.87746.
During locomotion, soft-bodied terrestrial animals solve complex control problems at substrate interfaces, but our understanding of how they achieve this without rigid components remains incomplete. Here, we develop new all-optical methods based on optical interference in a deformable substrate to measure ground reaction forces (GRFs) with micrometre and nanonewton precision in behaving larvae. Combining this with a kinematic analysis of substrate-interfacing features, we shed new light onto the biomechanical control of larval locomotion. Crawling in larvae measuring ~1 mm in length involves an intricate pattern of cuticle sequestration and planting, producing GRFs of 1-7 µN. We show that larvae insert and expand denticulated, feet-like structures into substrates as they move, a process not previously observed in soft-bodied animals. These 'protopodia' form dynamic anchors to compensate counteracting forces. Our work provides a framework for future biomechanics research in soft-bodied animals and promises to inspire improved soft-robot design.
在运动过程中，软体陆地动物在基底界面上解决了复杂的控制问题，但我们对它们如何在没有刚性组件的情况下实现这一点的理解还不完整。在这里，我们开发了新的全光学方法，该方法基于可变形基底中的光干涉，以在行为幼虫中以微米和纳牛顿的精度测量地面反作用力（GRF）。将其与基底界面特征的运动学分析相结合，我们为幼虫运动的生物力学控制提供了新的认识。在长度约为 1 毫米的幼虫中爬行涉及到一种复杂的表皮隔离和种植模式，产生 1-7 µN 的 GRF。我们表明，幼虫在移动时将具有齿状结构的、类似脚的结构插入并扩展到基底中，这一过程以前在软体动物中没有观察到。这些“原足”形成动态锚来补偿抵消的力。我们的工作为软体动物的未来生物力学研究提供了一个框架，并有望激发对软机器人设计的改进。
