Robot performance has advanced considerably both in and out of the factory, however in tightly constrained, unknown environments such as inside a jet engine or the human heart, current robots are less adept. In such cases where a borescope or endoscope can't reach, disassembly or surgery are costly. One promising inspection device inspired by plant growth are "vine robots" that can navigate cluttered environments by extending from their tip. Yet, these vine robots are currently limited in their ability to simultaneously steer into tight curvatures and apply substantial forces to the environment. Here, we propose a plant-inspired method of steering by asymmetrically lengthening one side of the vine robot to enable high curvature and large force application. Our key development is the introduction of an extremely anisotropic, composite, wrinkled film with elastic moduli 400x different in orthogonal directions. The film is used as the vine robot body, oriented such that it can stretch over 120% axially, but only 3% circumferentially. With the addition of controlled layer jamming, this film enables a steering method inspired by plants in which the circumference of the robot is inextensible, but the sides can stretch to allow turns. This steering method and body pressure do not work against each other, allowing the robot to exhibit higher forces and tighter curvatures than previous vine robot architectures. This work advances the abilities of vine robots--and robots more generally--to not only access tightly constrained environments, but perform useful work once accessed.

翻译：机器人性能在工厂内外均取得了显著进步，然而在诸如喷气发动机内部或人类心脏等高度受限且未知的环境中，现有机器人仍显得力不从心。当内窥镜或管道镜无法抵达时，拆卸或手术的成本往往高昂。一种受植物生长启发的检测装置——“藤蔓机器人”——通过从顶端延伸来穿越杂乱环境，展现出应用前景。然而，当前藤蔓机器人在同时实现小曲率转向及对环境施加显著作用力方面仍存在局限。本文提出一种受植物启发的转向方法，通过不对称地延长藤蔓机器人一侧，实现高曲率与大力矩施加。关键技术突破在于引入一种具有极高各向异性的复合褶皱薄膜，其正交方向的弹性模量差异达400倍。该薄膜被用作藤蔓机器人本体，其轴向可拉伸超120%，而周向仅能拉伸3%。结合可控层间夹紧机制，该薄膜实现了一种植物启发的转向方式：机器人周向不可伸长，但侧面可拉伸以完成转向。该转向方法与本体气压相互协同，使机器人展现出较以往藤蔓机器人架构更高的作用力与更小的曲率半径。本研究不仅提升了藤蔓机器人的能力（更广义而言，也为机器人整体），使其不仅能进入高度受限环境，还能在进入后执行有效工作。