In recent years, aging of bridges has become a growing concern, and the danger of bridge collapse is increasing. To appropriately maintain bridges, it is necessary to perform inspections to accurately understand their current state. Until now, bridge inspections have involved a visual inspection in which inspection personnel come close to the bridges to perform inspection and hammering tests to investigate abnormal noises by hammering the bridges with an inspection hammer. Meanwhile, as there are a large number of bridges (for example, 730,000 bridges in Japan), and many of these are constructed at elevated spots; the issue is that the visual inspections are laborious and require huge cost. Another issue is the wide disparity in the quality of visual inspections due to the experience, knowledge, and competence of inspectors. Accordingly, the authors are trying to resolve or ameliorate these issues using unmanned aerial vehicle (UAV) technology, artificial intelligence (AI) technology, and telecommunications technology. This is discussed first in this paper. Next, the authors discuss the future prospects of bridge inspection using robot technology such as a 3-D model of bridges. The goal of this paper is to show the areas in which deployment of the UAV, robots, telecommunications, and AI is beneficial and the requirements of these technologies.
When a volcano erupts, molten rocks, ash, pyroclastic flow, and debris flow can cause disasters. Debris flow is responsible for enormous damage across large areas. This makes debris flow simulations a crucial means of determining whether to issue an evacuation warning for area residents. For safety purposes, restricted areas are designated around volcanos during eruptions, making it difficult to gather information (such as the amount and permeability of ash) required for precise debris flow simulations. An unmanned observation system, intended for use in such restricted areas, was developed to address this issue. The proposed system is based on a multirotor micro-unmanned aerial vehicle (MUAV) that transports cameras, small devices to measure target environments, and a small robot to active volcanic areas.Several field tests were performed around active volcanoes for validation and system improvement. This study investigates five unmanned systems with field tests. The first one is an autonomous flight to collect three-dimensional (3D) terrain information. The MUAV conducted the long flight at Mt. Unzen-Fugen and evaluated the accuracy and calculation time of the developed 3D terrain model. The second one is a drop-down-type ash-depth measurement scale. The scales were deployed at Mt.Unzen-Fugen and confirmed its function. The third system is a soil-sampling device to estimate permeability. The device is hung from the MUAV by a long tether and collects soil and gravels directly with two rollers, while the MUAV is hovering. Indoor experiments were conducted to evaluate the performance of the device, and field experiments were conducted to confirm the validation of the system in different volcanic environments. The fourth system is an unmanned surface flow measurement device to estimate permeability. The device carries a water balloon and breaks it when it lands on the ground. By observing water flow with mounted cameras, qualitative permeability can be estimated. Initial experiments were conducted at Mt.Unzen-Fugen to confirm its function. The fifth system is a small ground vehicle with a rainfall sensor deployed by an MUAV. The MUAV carries a capturing net suspended from it and delivers and retrieves the ground vehicle, while it is hovering. Field experiments were conducted at Mt. Asama and Mt. Unzen-Fugen to validate the J Field Robotics. 2018;35:1222-1241. wileyonlinelibrary.com/journal/rob 1222 |
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.