Abstract
Soft grasping robot is an important research field in soft robot technology. It is a big problem for soft grippers to solve low load gripping and low grasping success rate. For solving these problems, a kind of enclosed structure soft gripper expansion type (ET) is proposed. The ET is driven by hydraulic or pneumatic system with stable force and high reliability. The ET is proposed based on an enclosed grasping mechanism, and based on the biomimetic underwater swallowing design method. The ET which has both advantages of economy and flexibility, self-adaptive grasps through negative pressure and positive pressure. The ET achieves the modular, mobile and adaptive grasping ability. The ET classifies as gripper A (GA) and gripper B (GB). GA has more load capacity, and GB can grab larger irregular objects. The maximum load that ET achieving is 30 N, which is able to reliably grasp objects and hold them with a force several times their weight. The side of the object is separated from the outside world as far as possible, and the inner wall of the ring is stuck to the object by the swallowing structure to the maximum extent, so as to improve the friction force as far as possible, achieve self-adaptation and save energy at the same time. When reducing the gap between the ring inner wall of the soft gripper and the target object, it further reduces the gap through pressure in case of emergencies, so as to better grip force, so that the gripper has a better fault tolerance rate and inclusiveness when it holds the object.
