Design and motion analysis of a simple screw driven in-pipe inspection robot base on adaptive variable pitch

In-pipe inspection robot (IPIR) play an important role in detecting the quality of the inner walls of oil and gas transportation pipelines and urban pipelines. However, due to the complex structure of the pipeline, robot is required to have adaptability. The currently existing screw driven pipeline robot has a fixed pitch, and the robot passively and rigidly pass through pipeline curvature. This article designs a simple adaptive variable pitch pipeline robot. The robot is driven by an electric motor and has simple motion control. The robot consists of a rotor that can adapt to changes in pipeline diameter and a stator with fixed dimensions. The robot adapts through pipeline curvature by continuously adjusting the pitch. The robot is equipped with a wide-angle lens and transmits quality images of the inner wall of the pipeline through Wi-Fi. Through theoretical analysis and model experiments, the robot can smoothly pass through vertical pipes with a diameter of 160 mm and 90-degree pipeline curvature. • The robot has a new mechanical mechanism that changes the structure of the traditional stator and rotor. • The robot can operate stably within a 2.4-meter-long pipeline. • At the same time, the robot has certain ability to overcome obstacles and strong adaptability.