A research team led by Prof. Sadao Kawamura of Ritsumeikan University developed a spear-like underwater robot for the survey of layers below riverbed. It looks like a spear, and the user sticks it into the bottom and collects soil down to 50 cm. It is 2 m long and about 20 cm in diameter, and it moves using six screws in water. By controlling the position, it thrusts into the bottom at a right angle. The pipe on the top collects soil. The layer down to 50 cm from the bottom gives 5,000 years’ worth of information.
Traditionally, a submersible bigger than several tons is required for the survey of bottom layer. It is hard to increase the observation points because of required cost and labor. However, the newly-developed underwater robot can be operated by several people. Because it is possible to know the change of past temperatures and distribution of organism by surveying rocks and vestiges in the layer, the new robot expected to contribute to the research of climate change and natural disaster.