A prototype of a 3000m-class underwater glider for virtual mooring is being developed by JAMSTEC (Japan Agency for Marine-Earth Science and Technology) with RIAM (Research Institute for Applied Mechanics) of Kyushu University. The vehicle houses observation equipment and glides back and forth between the sea surface and the seabed collecting ocean data in a specific area (virtual mooring area). The motions of the vehicle are controlled by moving its center of gravity using mounted weight-shifters.

In the field experiments, although the vehicle is heeled by the weight-shifters, the phenomenon in which it did not turn was observed occasionally. Therefore, in this paper, its factor is examined by motion simulations. In the last part of the paper, the factor is verified by comparison of simulated results and field experimental results.