A Novel Soft Gripper Design Integrating a Unilateral Fingernail-Like Mechanism for Grasping Flat Object

Abstract

The grasping capabilities of robotic arms have been extensively studied by researchers in terms of accuracy, flexibility, and versatility, enabling robots to perform various tasks in domestic, industrial, and medical scenarios. However, grasping flat objects has remained a significant challenge and is often overlooked as a limiting case in robotic manipulation. To address this highly difficult task, this paper proposes a novel gripper design that combines a pneumatic soft gripper with a unilateral fingernail structure. We evaluate two grasping strategies and corresponding target generation methods tailored for this design. The proposed system significantly improves the success rate of stably grasping flat objects that lie flush on tables. Moreover, its soft interaction with the table surface reduces the need for highly precise object-table height detection, thereby saving computational time and cost. Finally, we conduct experimental tests on various common flat objects, validating the effectiveness of both the gripper design and the grasping strategies.