Tunnel Wall Survey and Inspection by Mobile Mapping
MIMM (Mobile Imaging technology systems & Mobile Mapping system) is a combined system of MIS (Mobile Imaging technology Systems) developed by Keisokukensa CO., Ltd. lighting tunnel walls and taking pictures to detect cracks visually, and MMS (Mobile Mapping System) developed by Mitsubishi Electric consisting of sensors such as GNSS, IMU and high precision LiDAR to detect any deformation of tunnel walls and road surface. Mitsubishi Electric?s MMS consisting the MIMM, obtains data of self position and posture from GNSS, IMU and odometer. Even with no GNSS reception, the system obtains initial and closing data of self position and posture, and gathers relative posture and maneuver in tunnels from the IMU and odometer installed (initialization of GNSS positioning and self-posture is mandatory). The high precision LiDAR not only enables survey in good GNSS reception but also realizes high performance of relative accuracy in tunnels. The most important factor upon tunnel inspection and survey is not quite ?where precisely?, but the ?state and how much? the deformation is from a certain landmark point. This system is mobile thus enables inspection and survey of far efficiency compared with static LiDAR utilization and can obtain data of equivalent accuracy Actual data obtained by the system and examples of its use shall be shown during the presentation.