With the continuous expansion of robotic application scenarios, there is an urgent demand for end-effectors that integrate adaptive dexterity with robust grasping force – a requirement that existing flexible grippers often fail to satisfy. This paper aims to overcome the limitations of traditional flexible grippers, such as insufficient grasping force and lack of an adjustable grasping range, by proposing a multimode variable-stiffness flexible gripper.
A four-finger gripper structure is designed, incorporating a variable-height chambers, particle blocking variable-stiffness technology and a rotating disk-slider mechanism. A mathematical model relating bending angle to air pressure is established based on the Yeoh model to validate the performance of the variable-height chambers.
This paper designs a multimode variable-stiffness flexible gripper and conducts experimental verification on it. Experimental results indicate that the maximum grasping weight of the variable-stiffness gripper increases from 289.5 to 392 g, achieving a 35.4% improvement. The gripper also exhibits excellent adaptability and stability across various grasping modes.
This paper innovatively integrates the variable-height chamber structure with variable-stiffness technology, which significantly improves the grasping force of the flexible gripper. In addition, a unique rotating disk-slider mechanism was designed to realize synchronous centrifugal/centripetal movements of the four fingers, thus expanding the grasping range of the flexible gripper. Meanwhile, the flexible gripper can switch between multiple grasping modes, which significantly enhances its adaptability to grasped objects.
