Hebei Provincial Key Laboratory of Parallel Robot and Mechatronic System, Yanshan University, Qinhuangdao, 066004,People's Republic of China.
Key Laboratory of Advanced Forging & Stamping Technology and Science (Yanshan University), Ministry of Education of China, Qinhuangdao, 066004, People's Republic of China.
Bioinspir Biomim. 2022 Oct 18;17(6). doi: 10.1088/1748-3190/ac8c10.
Rigid-flexible-soft coupled robots are an important development direction of robotics, which face many theoretical and technical challenges in their design, manufacture, and modeling. Inspired by fishbones, we propose a novel cable-driven single-backbone continuum robot which has a compact structure, is lightweight, and has high dexterity. In contrast to the existing single-backbone continuum robots, the middle backbone of the continuum robot is serially formed by multiple cross-arranged bioinspired fishbone units. The proposed bioinspired fishbone unit, having good one-dimensional bending properties, is a special rigid-flexible-soft structure mainly made by multi-material 3D printing technology. The unique design and manufacture of the middle backbone provide the continuum robot with excellent constant curvature characteristics and reduce the coupling between different motion dimensions, laying a foundation for the continuum robot to have a more accurate theoretical model as well as regular and controllable deformation. Moreover, we build the forward and inverse kinematics model based on the geometric analysis method, and analyze its workspace. Further, the comparison between the experimental and theoretical results shows that the prediction errors of the kinematics model are within the desired 0.5 mm. Also, we establish the relation between the cable driving force of the bioinspired fishbone unit and its bending angle, which can provide guidance for the optimization of the continuum robot in the future. The application demos prove that the continuum robot has good dexterity and compliance, and can perform tasks such as obstacle crossing locomotion and narrow space transportation. This work provides new ideas for the bioinspired design and high-precision modeling of continuum robots.
刚柔软耦合机器人是机器人的一个重要发展方向，在其设计、制造和建模方面面临许多理论和技术挑战。受鱼骨启发，我们提出了一种新型的缆驱动单骨干连续体机器人，它具有结构紧凑、重量轻、灵巧度高等特点。与现有的单骨干连续体机器人不同，连续体机器人的中间骨干由多个交叉排列的仿生鱼骨单元串联形成。所提出的仿生鱼骨单元具有良好的一维弯曲特性，是一种特殊的刚柔软结构，主要由多材料 3D 打印技术制成。中间骨干的独特设计和制造为连续体机器人提供了优异的恒曲率特性，并减少了不同运动维度之间的耦合，为连续体机器人具有更精确的理论模型以及规则可控的变形奠定了基础。此外，我们基于几何分析方法建立了正向和逆向运动学模型，并分析了其工作空间。进一步的，实验和理论结果的对比表明，运动学模型的预测误差在期望的 0.5mm 以内。此外，我们建立了仿生鱼骨单元的缆索驱动力与其弯曲角度之间的关系，这可为连续体机器人的优化提供指导。应用演示证明了连续体机器人具有良好的灵巧性和柔顺性，能够完成越障运动和狭小空间运输等任务。这项工作为连续体机器人的仿生设计和高精度建模提供了新的思路。
