Research On Steering Gear Control System Of Underwater High Speed Robot

Most of the body of the high-speed underwater robot is wrapped by cavitation,which can greatly reduce the navigation resistance and achieve ultra-high speed navigation.Underwater high-speed robot has great application prospects in the field of underwater high-speed weapons.Russia,the United States,Germany and other naval powers have invested a lot of manpower and material resources to study it,but the research in this field in China is still relatively backward.As an important actuator of underwater high-speed robot,the performance of its control system will directly determine whether the underwater high-speed robot can navigate stably and its navigation quality.Therefore,this paper studies the steering control system of underwater high-speed robot.The main research work of this paper is as follows:The structure and working principle of underwater high-speed robot are introduced;Then,the force of each part of the robot is analyzed in detail and its mathematical model is established in the longitudinal plane;Finally,by analyzing the deflection characteristics,force characteristics and working environment of the two control rudders of the cavitator and the tail of the underwater high-speed robot,the performance requirements of the rudder system are summarized: the rudder needs to accurately track the rapidly changing position signal under the condition of high-frequency variable load and model parameter changes.The actuator drive mechanism of cavitator and tail is designed and analyzed.The calculation method of equivalent moment of inertia and actuator load is given;Then the PMSM is selected as the power source of the actuator,its mathematical model is established and the vector control method is introduced;Finally,the position tracking system of the two rudders is constructed based on the vector control method.The traditional three closed-loop position tracker is designed and improved.According to the performance requirements of the actuator,the fast position tracking strategy("speed feedforward"),anti load disturbance strategy("torque feedforward")and anti model parameter time-varying strategy("fuzzy control")are combined to design the "three closed-loop + speed fuzzy feedforward + Torque Fuzzy Feedforward" position tracker;Then,three groups of simulation experiments show the effectiveness of "speed feed forward","torque feed forward" and "fuzzy control" in improving the position tracking performance of the actuator.The joint simulation model of "underwater high speed robot steering gear" is constructed by combining the model of underwater high-speed robot and the model of steering gear;Then,based on the joint model,the improved actuator position tracker is simulated.The simulation results further verify the effectiveness of the proposed actuator position tracker in the control system of the underwater high-speed robot.And the improved position tracker has some reference and potential application value in other industrial automation fields with the same performance requirements.