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AUV HATTORI: A lightweight platform for high-speed low-altitude survey of rough terrains

This paper introduces our new AUV HATTORI and scanning sonar based terrain tracking algorithm implemented in the vehicle. The AUV HATTORI (Highly Agile Terrain Tracker for Ocean Research and Investigation) is a lightweight and low-cost testbed designed for rapid and efficient imaging of rugged seafloor, such as coral reefs. Most of current AUVs suitable for seafloor imaging are heavy and expensive, requiring a crane-equipped vessel for their operation. As HATTORI is one-man portable, it can be operated from any available boat. In the terrain tracking algorithm, the seafloor surface is estimated based on the potential method using the measurements of a scanning sonar and basic status of the vehicle, or depth, attitude and surge speed. The path to be followed is generated based on the algorithm. The AUV succeeded in following a rocky terrain at the altitude of around 2m, with a surge speed of around 0.8m/s.