Development of a Cleaning Robot Capable of Self-Propelled Cleaning for Ducts in Real-World Environments Employing a Planetary Gear Mechanism

Abstract

This study develops an autonomous cleaning robot designed to remove accumulated grease in restaurant kitchen ducts, where human access and manual cleaning are not feasible. Prior studies have developed cleaning mechanisms for round ducts employing planetary gear systems, demonstrating their efficiency in grease removal. However, these systems lack propulsion mechanisms, and cleaning experiments have been limited to short-distance, small-diameter pipes (140 mm, 100A). Therefore, no system has been developed for cleaning grease in long-distance, large-diameter ducts in real-world environments. To address this limitation, we developed a self-propelled cleaning robot integrating a planetary gear-based cleaning mechanism and an inchworm-inspired propulsion mechanism. The design of the propulsion mechanism involved modeling brush rotational torque, gripping torque, and gripping force. Based on this model, a duct inspection and cleaning robot equipped with both propulsion and cleaning mechanisms was developed. Subsequently, the developed robot was tested in a 9 m mock-up duct to evaluate its self-propelled cleaning performance. The robot removed an average of over 85% of the grease under all test conditions while operating autonomously. Finally, a cleaning experiment was conducted in a butcher shop duct, where the robot removed most of the adhered grease. These experiments demonstrated that the developed robot can autonomously clean and inspect ducts in real-world environments where human entry is impractical.