An Active Steering Soft Robot for Small-Bore T-Branch Pipeline

Tianbo Li, Yang Yang, Yonggan Liu, Yongjian Zhao, Yan Peng, Jun Ke, Yuyi Zhai

Abstract: The existing small-bore in-pipe robots are difficult to pass through complicated pipelines such as T-branch pipeline. Aiming at the challenge, this study designs an active steering robot with better flexibility and over-bending capability, which is suitable for small pipelines inspection. It is made of compliant silica gel and 3D printed mold and consists mainly of three parts, wherein the middle axial actuator has three uniform fan-shaped cavities through special design. The air pressure of the three cavities can be adjusted according to different turning requirements to realize active turning in the pipeline. In addition, the kinematics model of the in-pipe robot is established, and the relationship between the center position of the robot head and the air pressure of the three cavities is deduced, which provides theoretical support for the motion control of the robot. Finally, the accuracy of the model and the performance of the robot are verified by the experiments.