Development of Shuttle Type AUV “ALBAC” and Sea Trials for Oceanographic Measurement

The ALBAC designed by the authors and constructed in 1992 is a prototype of shuttle type autonomous underwater vehicles. The ALBAC was developed for the oceanographic measurement of water column on the way and from the seabed.The vehicle does not have a propeller thruster but moves aside by gliding. To carry out the mission, the software includes three simple fuzzy controllers for longitudinal and lateral motion. The longitudinal motion controller displaces the longitudinal coordinate of the location of the center of gravity (C. G.) and controls the gliding angle, respectively of the vehicle. Two lateral motion controllers also displace the lateral coordinate of C. G. and control azimuth and yaw rate. The parameters of the fuzzy rules were optimized by using the Evolution Strategies on the simulator, and examined based on the motion data of every trial. 300-meter depth sea trials were successfully conducted in April of 1995 at the Suruga Bay of Japan.Consequently, the ALBAC is highly reliable and can be easily operated to carry out the mission to measure the profile of scientific data.