The use of a soft multi-fingered hand in handling fragile objects has been widely acknowledged. Nevertheless, high flexibility often results in decreased load capacity, necessitating the need for variable stiffness. This article introduces a new soft multi-fingered hand featuring variable stiffness. The finger of the hand has three chambers and an endoskeleton mechanism. Two chambers facilitate bending and swinging motions, whereas the third adjusts stiffness. An endoskeleton mechanism is embedded in the third chamber, and the friction between its moving parts increases as negative air pressure rises, causing the finger's stiffness to increase. This mechanism can alter its stiffness in any configuration, which is particularly useful in manipulating irregular-shaped fragile objects post-grasping. The effectiveness of the proposed soft multi-fingered hand is validated through five experiments: stiffness adjustment, finger stiffening under a specific orientation, bulb screwing, heavy object lifting, and bean curd grasping. The results demonstrate that the proposed soft multi-fingered hand exhibits robust grasping capabilities for various fragile objects.

中文翻译：

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具有可变刚度的内骨骼柔软多指手。


使用柔软的多指手来处理易碎物品已得到广泛认可。然而，高灵活性通常会导致负载能力下降，从而需要可变刚度。本文介绍了一种具有可变刚度的新型柔软多指手。手的手指具有三个室和一个内骨骼机构。两个腔室促进弯曲和摆动运动，而第三个腔室则调节刚度。第三腔室中嵌入了一个内骨骼机构，其运动部件之间的摩擦力随着负气压的升高而增加，导致手指的僵硬增加。该机构可以在任何配置中改变其刚度，这在抓取后操纵不规则形状的易碎物体时特别有用。通过五个实验验证了所提出的软多指手的有效性：刚度调整、特定方向下的手指硬化、灯泡拧紧、重物举起和豆腐抓。结果表明，所提出的软多指手对各种易碎物体表现出强大的抓取能力。