Effect of changing properties of in-pipe inspection robot and payload capacity on its performance

The performance of screw-drive in-pipe inspection robots is significantly influenced by factors such as wheel tilting angle, coefficient of friction, and spring constant. A comprehensive understanding of these parameters is critical for the effective design, optimization, and control of the robot, particularly to enhance energy efficiency and payload capacity during vertical pipeline inspections. In this study, we developed a mathematical model based on discrete Lagrangian mechanics to formulate an optimization problem aimed at minimizing power consumption and maximizing payload capacity under various dynamic constraints and design conditions. Our results show that increasing the wheel tilt angle allows the robot to ascend more quickly; however, it also leads to a substantial rise in power consumption, by approximately 70% as the tilt angle increases from 30° to 80°. Furthermore, while increasing the spring constant can improve the robot’s ability to carry heavier loads, it can also hinder its performance in climbing vertical pipes. Through optimization, the robot is capable of carrying a payload equivalent to approximately 60% of its own weight while maintaining the increase in power consumption below 40%.