The difficulties of traditional rigid/soft grippers in meeting the increasing performance expectations (e.g., high grasping adaptability and wide graspable objects range) of a single robotic gripper have given birth to numerous soft-rigid coupling grippers with promising performance. However, it is still hard for these hybrid grippers to adaptively grasp various objects with diverse fragilities intact, such as incense ash and orange, due to their limited contact stiffness adjustable range and compliance. To solve these challenging issues, herein, we propose a dual-modal hybrid gripper, whose fingers contain a detachable elastomer-coated flexible sheet that is restrained by a moving frame as a teardrop shape. The gripper's two modes switched by controlling the moving frame position can selectively highlight the low contact stiffness and excellent compliance of the teardrop-shaped flexible sheets and the high contact stiffness of the moving frames. Moreover, the contact stiffness of the teardrop-shaped sheets can be wide-range adjusted by online controlling the moving frame position and offline replacing the sheets with different thicknesses. The compliance of the teardrop-shaped sheets also proves to be excellent compared with an Ecoflex 10 fingertip with the same profile. Such a gripper with wide-range tunable contact stiffness and high compliance demonstrates excellent grasping adaptability (e.g., it can safely grasp several fragile strawberries with a maximum size difference of 18 mm, a strawberry with a left/right offset of 3 cm, and a strawberry in two different lying poses) and wide-range graspable objects (from 0.1 g super fragile cigarette ashes to 5.1 kg dumbbell).

中文翻译：

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一种双模态混合夹具，具有宽可调接触刚度范围和高顺应性，适用于自适应和宽范围抓取具有不同脆弱性的物体。

传统的刚/软机械手难以满足单个机器人机械手日益增长的性能期望（例如，高抓取适应性和宽抓取物体范围），催生了众多性能良好的软-刚耦合机械手。然而，由于接触刚度可调范围和柔顺性有限，这些混合夹具仍然很难自适应地完整地抓取具有不同脆弱性的各种物体，例如香灰和橙子。为了解决这些具有挑战性的问题，我们提出了一种双模式混合夹具，其手指包含可拆卸的弹性体涂层柔性片，该柔性片被移动框架限制为泪滴形状。通过控制移动框架位置来切换夹具的两种模式，可以选择性地突出泪滴状柔性片材的低接触刚度和优异的柔顺性以及移动框架的高接触刚度。此外，通过在线控制移动框架位置和离线更换不同厚度的板材，可以大范围调节水滴形板材的接触刚度。与具有相同轮廓的 Ecoflex 10 指尖相比，泪滴状片材的顺应性也被证明非常出色。这种具有宽范围可调接触刚度和高柔顺性的机械手表现出优异的抓取适应性（例如，它可以安全地抓取多个最大尺寸差异为18毫米的易碎草莓、左右偏移为3厘米的草莓以及一个草莓）。两种不同躺姿的草莓）和各种可抓握物体（从 0.1 克超易碎烟灰到 5.1 公斤哑铃）。