Design of Enveloping Underwater Soft Gripper Based on the Bionic Structure

The ocean has been an important research site for scientists in recent years. Many marine creatures with soft bodies such as sea cucumbers are fragile and easily deformed, so it is difficult when grasping these kinds of targets. In this regard, this study developed an underwater soft robot gripper based on a bionic structure. By imitating the envelope structure of the Venus flytrap, the soft robot gripper was designed with a soft finger envelope plate, and the structure was designed by imitating human finger fingerprints. The large and small pressure chambers of soft fingers were designed with the characteristics of different lengths of the segments. By adopting these bionic elements, the grasping ability of the gripper has been greatly improved. The structural parameter optimization design of soft fingers, based on finite element simulation, has been described detailed in the paper. The declination between the simulation results and the actual results is very small, which proves that the accuracy of the optimization method is high. In the simulated underwater environment, some models and living sea cucumbers were grasped for tests. Finally, the experimental results proved that the soft robot gripper can achieve the goal of stable grasping for different objects.