A Localization Method for Manta Robots Using an Optical Flow Technique

—In order for an underwater robot to investigate an investigation environment everywhere, it needs to grasp an own position. However, since underwater is the environment where an electric wave does not arrive, it cannot acquire position information from GPS (Global Positioning System) etc. Moreover, small AUVs like the Manta robot are difficult to use a large-sized sensor for ships. Therefore, in this research, we build a localization technique suitable for small AUVs like the Manta robot. It discusses about the optical flow technique suitable for the Manta robot, and verifies about the influence of change of the height from a camera to an object. Furthermore, after pointing out that the pitch movement of the Manta robot influences the detection of an optical flow greatly, in this paper, an oscillatory motion that is similar to the pitch movement of the Manta robot is artificially given to an optical flow, and we discuss about its influence.