Underground Mobile Mapping

Common mobile mapping systems heavily rely on positioning using GNSS. However, concrete, soil and other materials block GNSS signals, thus impeding their use when inspecting pipelines, subways or other underground corridors. Furthermore, such corridors are often narrow, which requires the system to be compact. Here, the author describes a platform equipped with laser scanners and a camera which has been developed in Japan for mapping a wide variety of narrow underground spaces.