Fuzzy logic PID based control design for a biomimetic underwater vehicle with two undulating long-fins

This paper proposes a fuzzy logic PID based control method for a biomimetic underwater vehicle on swimming speed and yaw angle. The vehicle has a pair of long-fins installed symmetrically on its body. A set of inertial sensors are applied for collecting its velocity and pose information. And an embedded control system and a driving system based on FPGA are designed for generating and switching motion modes. Based on its motion discipline and system architecture, black-box identification is employed for system modeling. Therefore, according to the control system and driving system, a fuzzy logic PID control scheme is proposed for the underwater vehicle. A fuzzy logic controller is applied for the vehicle before the error is reduced to a given range. Then PID controller is applied when the error is within the given range. Here, velocity control is considered, which involves swimming speed and yaw angle. The fuzzy logic PID control scheme is used for the goals respectively. And Yaw angle control is prior to the swimming speed control. Finally, simulation results show the proposed control scheme is valid.