机械抓手是一类重要的机器人末端执行机构，用于取放、操作和搬运物体。目前，自动化生产线只实现了部分刚性和规则物体的自动化抓取，而大部分异形和易损物品仍采用人工上下料。抓手研究的关键技术挑战之一是如何增强其对所抓取物体多样性的适应能力。在本文中，适应性的具体内涵包括：对物体尺寸的适应性，对物体形状的适应性，以及对物体摆放位置的容错性等。流体弹性体抓手具有独特的本体柔顺性，能提供一定的被动适应性，然而其适应性仍有待进一步提高。本文从人手丰富的功能和结构中获取灵感，在流体弹性体结构的基础上，融入刚性结构，设计新型的仿生多指抓手构型、结构与抓持策略，以提高抓手对所抓持物体的尺寸、形状和位置的适应性，具体研究内容如下： 从人手手掌在抓取中的作用出发，提出具有可变手掌的新型多指软体抓手构型，设计了一种可在小空间范围内大幅度变间距变角度的类手掌机构，提出了一款具有可调初始抓握姿势的多指抓手。研制了变间距驱动器、变角度驱动器、手指驱动器等关键部件，并基于弹性力学对关键驱动器进行了刚度建模。最后，在YCB（Yale–Carnegie Mellon University–Berkeley）数据集上进行了抓取能力测试，验证了该抓手构型提高了对物体尺寸的适应能力。 从人手手指刚柔耦合结构中获取灵感，提出一种基于流体弹性体驱动器的外柔内刚新手指结构，通过内部半主动骨骼的关节刚度调整和外部柔性皮肤的欠驱动运动来协同实现对物体形状的主动适应。研制了具有刚度调整能力的移动和转动关节结构，进而构建了刚柔耦合的两指抓手，并设计了其形状适应抓取策略，实现了对于圆柱和棱柱的适应性贴合，提升了对于不同形状物体的适应能力。 根据人手抓取细长管状类物体的姿态特征，设计了一种“双囊双指”的仿生末端执行器，通过柔性囊状驱动器的周向失稳变形进行咽拭子末端结构的稳定抓持，并通过双指的夹持进一步提高了抓持稳定性。同时，利用柔性囊的本体柔顺性提升了对物体位置偏差的容错性。与刚性机械臂结合，研制了机器人采样系统，实现了医患隔离的全流程自动化咽拭子采样。 本论文的工作为仿生多指抓手的适应性增强提供了新思路，为机械抓手的实用化设计与规模化应用提供了关键技术。

The mechanical gripper is an essential type of robotic end effectors, which is used to pick and place, manipulate, and transport objects. Current automated production lines, however, have only achieved the grasping of some rigid and regular-shaped objects, while most irregular and fragile items still require manual handling. One of the key technological challenges in gripper development is how to enhance its adaptability to a wide range of objects. In this dissertation, adaptability is specified as: adaptability to object size, adaptability to object shape, and error tolerance for object placement. Fluidic elastomer grippers exhibit unique compliance, which provides certain passive adaptability; however, their adaptability still requires further enhancement. Inspired by the rich functionality and structure of the human hand, this dissertation proposes novel designs for multi-finger grippers based on fluidic elastomers and the incorporation of rigid structures, including new configurations, structures, and grasping strategies, aiming to improve the grippers’ adaptability to object size, shape, and placement. The main research contents are as follows: Inspired by the functions of human hand palm in grasping, a novel multi-finger gripper configuration with an adjustable palm is proposed. A palm-like mechanism is designed to achieve sufficient adjustment in the distance and angle between the fingers within a small spatial occupation. A multi-finger gripper with adjustable initial grasping posture is developed based on this new configuration, and the key components of the gripper including the distance-adjusting actuator, angle-adjusting actuator, and finger actuator are investigated. A model of the key actuator’s stiffness is proposed based on elastic mechanics. Grasping tests are performed on the YCB dataset, verifying that the gripper can effectively improve the gripper’s adaptability to object dimensions. Inspired by the soft-rigid coupled structure of human fingers, a new finger structure based on fluid elastic actuators is proposed, which achieves shape adaptability through the coordination of the joint stiffness adjustment in the internal semi-active bones and the underactuated motion of the external flexible skin. The prismatic and rotary joints structure with the ability to adjust their stiffness are developed and a soft-rigid hybrid two-finger gripper is constructed. A shape-adaptive grasping strategy is designed for the gripper, enabling it to achieve the adaptive conformal grasping of both cylindrical and prismatic objects, therefore increasing the gripper’s adaptability to objects shapes. Based on the grasping characteristics of human hands grasping slender and tubular objects, a bioinspired end effector with "double capsules and two fingers" is designed. It utilizes the circumferential instability deformation of the capsule actuator to achieve stable grasping of the oropharyngeal swab. The grasping stability is further improved through the clamping of the two fingers. At the same time, the inherent compliance of the soft capsule actuator improves the tolerance of the gripper to positional deviations during grasping. Combining with a rigid robotic arm, a robotic sampling system is developed and finishes the whole process of automatic throat swab sampling for doctor-patient isolation. The work in this dissertation provides new insights for the enhancement of the adaptability of the bioinspired multi-finger grippers, and provides key technologies for the practical design and large-scale application of robotic grippers.