Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education, School of Mechanical Engineering, Tianjin University, Tianjin, China.
School of Electronic and Electrical Engineering, University of Leeds, Leeds, United Kingdom.
Soft Robot. 2024 Feb;11(1):171-182. doi: 10.1089/soro.2023.0014. Epub 2023 Oct 4.
This article presents a novel extensible continuum robot (ECR) with growing motion capability for improved flexible access in transoral laryngeal procedures. The robot uses an extensible continuum joint with a staggered V-shaped notched structure as the backbone, driven by the pushing and pulling of superelastic Nitinol rods. The notched structure is optimized to achieve a wide range of extension/contraction and bending motion for the continuum joint. The successive and uniform deflection of the notches provides the continuum joint with excellent constant curvature bending characteristics. The bidirectional rod-driven approach expands the robot's extension capabilities with both pushing and pulling operations, and the superelasticity of the driving rods preserves the robot's bending performance. The ECR significantly increases motion dexterity and reachability through its variable length, which facilitates collision-free access to deep lesions by following the anatomy. To further exploit the advantages of the ECR in path-following for flexible access, a growing motion approach inspired by the plant growth process has been proposed to minimize the path deviation error. Characterization experiments are conducted to verify the performances of the proposed ECR. The extension ratio achieves up to 225.92%, and the average distal positioning error and hysteresis error values are 2.87% and 0.51% within the ±120° bending range. Compared with the typical continuum robot with a fixed length, the path-following deviation of this robot is reduced by more than 58.30%, effectively reducing the risk of collision during access. Phantom experiments validate the feasibility of the proposed concept in flexible access procedures.
本文提出了一种具有增长运动能力的新型可延展连续体机器人（ECR），用于改善经口喉部手术中的灵活进入。机器人使用带有交错 V 形切口结构的可延展连续体关节作为骨干，由超弹性 Nitinol 棒的推动和拉动驱动。切口结构经过优化，可实现连续体关节的大范围伸缩和弯曲运动。切口的连续均匀偏转使连续体关节具有出色的恒曲率弯曲特性。双向杆驱动方法通过推和拉操作扩展了机器人的延伸能力，并且驱动杆的超弹性保持了机器人的弯曲性能。ECR 通过其可变长度显著提高了运动灵活性和可达性，通过跟随解剖结构实现了对深部病变的无碰撞进入。为了进一步利用 ECR 在灵活进入中的路径跟踪优势，提出了一种受植物生长过程启发的增长运动方法，以最小化路径偏差误差。进行了特征描述实验来验证所提出的 ECR 的性能。在±120°弯曲范围内，扩展比高达 225.92%，并且远端定位误差和滞后误差的平均值分别为 2.87%和 0.51%。与具有固定长度的典型连续体机器人相比，该机器人的路径跟踪偏差减少了 58.30%以上，有效地降低了进入过程中的碰撞风险。在仿体实验中验证了该机器人在灵活进入手术中的可行性。
