Prototype Design of a Multi-Mode Switching Module with Locking Mechanism for Water-Proof Pipeline Inspection Robots

This paper proposes a prototype design of tracked in-pipe inspection robot that possesses two functions: translating along the pipeline axis and rotating within the pipeline, with the ability to switch between these two functions. This robot requires only a minimal complement of ultrasonic sensors, enabling it to accomplish a 360-degree wall thickness inspection by means of rotation. This approach significantly contributes to cost savings in the inspection process. The design of this robot consists of the track, rotation, and switching modules. The track module is a mechanism moving forward or backward for this robot, The rotation module is used for the motion of the robot turning in the pipe. The switching module allows for seamless transition between the track and rotation modes. The switching module is driven by a single motor and incorporates a locking mechanism to ensure that at least one pair of modules support the robot against the pipe wall during the mode transition, thereby maintaining the robot's posture. To validate the design, motion simulations were conducted using SolidWorks. Then, we performed movement tests on the track, rotation, and switching modules in a real pipe. The test results confirm the feasibility of the prototype design.