Development of an In-Pipe Robot with a Novel Differential Mechanism

Abstract

An in-pipe robot with a novel differential mechanism is developed for solving the movement interference problem of wheel-type in-pipe robots, when driving through the pipelines with irregular internal wall or complex conditions. Based on the four-axial differential mechanism, the differential locomotion of the in-pipe robot is only forced by the contact conditions of driving wheels without additional control signals. The mechanical model of the pipe diameter adaptive mechanism applying a typical ball screw pair is established, which is validated by the following simulation experiment and shows high reliability. The active steering mechanism with two rotational degrees of freedom is designed and meanwhile, the brake mechanism for preventing driving wheels from slipping and the elastic support mechanism for front-end support are introduced. Subsequently, the planned steering trajectory of the robot turning in a branch pipe is given and discussed. Finally, the validation of the in-pipe robot is demonstrated by the simulation experiments.