Soft grippers have great potential applications in daily life, since they can compliantly grasp soft and delicate objects. However, the highly elastic fingers of most soft grippers are prone to separate from each other while grasping objects due to their low stiffness, thus reducing the grasping stability and load-bearing capacity. To tackle this problem, inspired from the venus flytrap plant, this work proposes a mutual-hook mechanism to restrain the separation and improve the grasping performance of soft fingers. The novel soft gripper design consists of three modules, a soft finger-cot, two Soft Hook Actuators(SHAs) and two sliding mechanisms. Here, the soft finger-cot covers on the soft finger, increasing the contact area with the target object, two SHAs are fixed to the left and right sides of the finger-cot, and the sliding mechanisms are designed to make SHAs stretch flexibly. Experiments demonstrate that the proposed design can restrain the separation of soft fingers substantially, and the soft fingers with the finger-cots can grasp objects three times heavier than the soft fingers without the proposed design. The proposed design can provide invaluable insights for soft fingers to restrain the separation while grasping, thus improving the grasping stability and the load-bearing capacity.

软质抓手在日常生活中具有巨大的潜在应用，因为它们可以顺从地抓取柔软而精致的物体。然而，大多数软质抓手的高弹性手指由于刚度较低，在抓取物体时容易彼此分离，从而降低了抓取稳定性和承载能力。为了解决这个问题，受捕蝇草植物的启发，这项工作提出了一种互钩机制来抑制分离并提高软手指的抓取性能。新颖的软夹具设计由三个模块组成：一个软指套、两个软钩执行器（SHA）和两个滑动机构。这里，柔软的指套覆盖在柔软的手指上，增加了与目标物体的接触面积，两个SHA固定在指套的左右两侧，滑动机构的设计使SHA可以灵活拉伸。实验表明，所提出的设计可以充分抑制软手指的分离，并且带有指套的软手指可以抓取比没有所提出的设计的软手指重三倍的物体。该设计可以为软手指在抓取时抑制分离提供宝贵的见解，从而提高抓取稳定性和承载能力。