Impact of Tire Shape on Localization Accuracy in Piping Inspection Robots

Abstract

The sewerage pipes laid in Japan are extensive, spanning approximately 470,000 km, with most of them constructed during the high economic growth period from around 1955 to around 1973. According to indicators from the Ministry of Land, Infrastructure, Transport, and Tourism, the service life of sewerage pipes is estimated at 50 years. This suggests that many sewer pipes across Japan, installed over 50 years ago, are becoming obsolete. Consequently, piping inspections using robots have commenced in Japan. Currently, stand-alone types that can be inspected by a single robot are garnering attention. Meanwhile, we have been conducting research and development with the aim of implementing a small, easily portable, stand-alone piping inspection robot. Furthermore, numerous stand-alone types have been employed to prevent falls by adjusting the tire shape or the distance between the axles. However, this hardware approach does not completely prevent falls. Therefore, we have opted for a software approach to explore measures to prevent falls by controlling driving, aiming to achieve the advanced localization required for this purpose. We are currently in the stage of verifying the localization. However, accurately measuring the robot's position and orientation using general measuring instruments is challenging due to the curved piping. Hence, we developed a specialized three-dimensional position-measuring instrument for piping inspection robots. In this paper, we utilize the instrument to examine the influence of tire shape on localization. Additionally, we demonstrate the effectiveness of the localization method in an environment where tire shape does not affect the outcome.