Design and Applications of Soft Actuators Based on Digital Light Processing (DLP) 3D Printing

Compared with rigid robots, soft robots have the advantages of strong environmental adaptability, good human-robot interaction, and simple control systems; therefore, soft actuators have been widely studied in recent years. Based on DLP 3D printing technology, this study makes three kinds of pneumatic soft actuators: the soft gripper with the auxetic structure, the Elongation Bellow Actuator (EBA) and the Omnidirectional Bending Bellow Actuator (OBBA). Through experimental testing and finite element simulation, it was found that these actuators have the characteristics of fast response, high stability and large driving force. In this paper, an out-pipe crawling soft robot and soft robotic arm using these three soft actuators are designed. The pipe robot can realize omnidirectional turning and adapt to different shapes and sizes of pipes, with a movement speed of 2.85 mm/s (0.016 body length/s) on the 44 mm diameter round cross-section pipe and 2.67 mm/s (0.015 body length/s) on the 30 mmx30 mm square cross-section pipe. At the same time, an innovative motion mode is designed for the pipe robot in an underwater environment, which provides new ideas for underwater pipe soft robots. And the soft robotic arm can achieve omnidirectional bending anda specific range of grasping work, and compared with the rigid body robot arm, it is small in size, low in mass and has a higher degree of freedom. Finally, by combining the robotic arm and pipe robot, this paper proposes a pipe soft robot collaboration system and simulates its function in industrial pipeline systems, which has good application prospects.