DESIGN AND FABRICATION OF PNEUMATIC SOFT GRIPPER

In this paper, a pneumatic soft gripper is proposed with inspiration from sea anemone. The gripper is composed of an actuator and several silicone tentacles. With the power of compressed air, the soft actuator expands and folds the tentacles. The gripper wraps tentacles around the object and highly compliant tentacles conforms to the shapes of an object, enveloping and holding it. The physical model is fabricated with 3D printed PLA mold and silicone gel. The gripping mechanics are analyzed according to the experimental gripping operations. On basis of the experimental and analysis result, the compliant gripping is realized while the stability is to be increased. So the tentacle structure is then improved by multi chamber soft body and vacuum jamming bag. The jamming bag is combined to the end of each tentacle, where the bag is filled with particles to conform to the object shape. Therefore, a reliable constraint is realized between the gripper and the object under vacuum conditions. The bending motion and shaping effect are verified through theoretical and experimental approaches. The important parameters in the vacuum jamming process are also obtained. With such device, soft adaptive bodies enlarges the contact area to adapt to the work -piece where vacuum jamming bags increase the gripping force and stability. It is convenient for universal gripping operation for objects with different shapes.