Abstract

Soft robotic grippers have gained much attention in recent years owing to their advantages of easy fabrication, flexibility, and adaptability. Inspired by the adhesion capability of gecko’s toe and tree frogs in nature, this study presents a soft robotic gripper made of fiber-reinforced actuator and bioinspired fibrillar adhesives for grasping circular objects with enhanced grasping capability. Theoretical models of the designed gripper are established for characterizing bending angle, blocking force, friction force, and weight-carrying capability. The contribution of this article is the theoretical derivation of an explicit approximation formula for calculating bending angle and grasping force of designed soft gripper under different inflation pressures. Correctness and robustness of the derived formula for bending angle approximation was verified by established three-dimensional finite element model of the designed actuator. With the bioinspired fibrillar adhesives, the friction force between gripper and grasped objects is transformed to load-controlled and area-dependent friction force, which is much greater than that of the traditional design. A two-fingered soft gripper with the newly designed fiber-reinforced actuator is analyzed to verify the derived mathematical model. These models will be beneficial for robotic design/fabrication/control.

摘要

近年来，软机器人抓手由于其易于制造，灵活性和适应性强的优点而备受关注。受到壁虎脚趾和树蛙在自然界中的粘附能力的启发，本研究提出了一种由纤维增强的致动器和生物启发的原纤维粘合剂制成的柔软的机械手，可增强圆形物体的抓握能力。建立设计的抓爪的理论模型，以表征弯曲角度，阻挡力，摩擦力和承重能力。本文的贡献是一个理论上的推导近似公式，用于计算设计的软夹持器在不同充气压力下的弯曲角度和抓力。通过所设计致动器的三维有限元模型，验证了所推导的弯角近似公式的正确性和鲁棒性。借助生物启发性原纤维粘合剂，抓具和被抓物体之间的摩擦力被转换为负载控制的且取决于面积的摩擦力，该摩擦力远大于传统设计。分析了带有新设计的纤维增强执行器的两指软爪，以验证导出的数学模型。这些模型将有利于机器人设计/制造/控制。这比传统设计要大得多。分析了带有新设计的纤维增强执行器的两指软爪，以验证导出的数学模型。这些模型将有利于机器人设计/制造/控制。这比传统设计要大得多。分析了带有新设计的纤维增强执行器的两指软爪，以验证导出的数学模型。这些模型将有利于机器人设计/制造/控制。