Abstract: In this paper, we propose a fully Soft Bionic Grasping Device (SBGD), which has advantages in automatically adjusting the grasping range, variable stiffness, and controllable bending shape. This device consists of soft gripper structures and a soft bionic bracket structure. We adopt the local thin-walled design in the soft gripper structures. This design improves the grippers’ bending efficiency, and imitate human finger’s segmental bending function. In addition, this work also proposes a pneumatic soft bionic bracket structure, which not only can fix grippers, but also can automatically adjust the grasping space by imitating the human adjacent fingers’ opening and closing movements. Due to the above advantages, the SBGD can grasp larger or smaller objects than the regular grasping devices. Particularly, to grasp small objects reliably, we further present a new Pinching Grasping (PG) method. The great performance of the fully SBGD is verified by experiments. This work will promote innovative development of the soft bionic grasping robots, and greatly meet the applications of dexterous grasping multi-size and multi-shape objects.

Key words: Fully soft bionic grasping device , · Local thin-walled grippers , · Soft bionic bracket , · Adjust grasping range automatically , · Segmental bending shape , · New pinching grasping method