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arXiv · 2511.03691

Source-Free Bistable Fluidic Gripper for Size-Selective and Stiffness-Adaptive Grasping

Zhihang Qin·Yueheng Zhang·Wan Su·Linxin Hou·Shenghao Zhou·Zhijun Chen·Yu Jun Tan·Cecilia Laschi
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Abstract

Conventional fluid-driven soft grippers typically depend on external sources, which limit portability and long-term autonomy. This work introduces a self-contained soft gripper with fixed size that operates solely through internal liquid redistribution among three interconnected bistable snap-through chambers. When the top sensing chamber deforms upon contact, the displaced liquid triggers snap-through expansion of the grasping chambers, enabling stable and size-selective grasping without continuous energy input. The internal hydraulic feedback further allows passive adaptation of gripping pressure to object stiffness. This source-free and compact design opens new possibilities for lightweight, stiffness-adaptive fluid-driven manipulation in soft robotics, providing a feasible approach for targeted size-specific sampling and operation in underwater and field environments.

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Zhihang Qin, Yueheng Zhang, Wan Su, Linxin Hou, Shenghao Zhou, Zhijun Chen, Yu Jun Tan, Cecilia Laschi. 2025-11-05. Source-Free Bistable Fluidic Gripper for Size-Selective and Stiffness-Adaptive Grasping. https://arxiv.org/abs/2511.03691

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