B Raeisy - Fars Engineering Research Center (F.E.R.C), Shiraz, Iran
A.A Safavi - Associate Professor of Electrical Engineering Department of Shiraz University
A.R. Khayatian - Associate Professor of Electrical Engineering Department of Shiraz University

In this study, the roll and yaw fuzzy control of an Autonomous Underwater Vehicle (AUV) will be addressed. Yaw and roll angles will be regulated using their errors and rates. The discussed AUV has four flaps at the end of the vehicle as actuators. Two rule bases and membership functionshave been chosen. Invoking the normalized steepestdescent optimization method, best values for the membership function variables are found. Finally, withcomparison of the response of the improved system in each case, the best is selected. Though the AUV is a completely nonlinear system, the simulation of the designed control system using the equations of motion shows desirable behaviour of designed fuzzy logic system.

AUV, optimization, fuzzy, control, normalized steepest descent