Research On Course Control Of Underwater Gliders

Underwater glider has become the most widely used underwater observation platform due to its low power consumption,low noise,long range,long endurance and high concealment.As the Marine environment in which the glider is located is complex and changeable,it cannot move according to the preset course in the actual navigation process.In order to ensure the glider has good maneuverability and stability under water and the accuracy of the data collected by the glider,the study of course control is an essential part.This paper takes "Petrel" underwater glider as the research object,compares the course tracking ability of the internal attitude control system and the external rudder control system,and introduces the fuzzy PID method to optimize the control algorithm of the internal attitude control system.The main research contents and results of this paper are as follows:(1)Based on the momentum and moment theorem,the dynamic model of "Petrel" glider is established,which takes into account the influence of internal eccentric mass rotation and tail rudder rotation on the attitude adjustment of the glider,and can reflect the dynamic characteristics of the glider under the control of the two control systems more accurately.Based on the dynamic equation,the relationship between the control inputs,such as net buoyancy,mass displacement,mass rotation Angle and stern rudder rotation Angle,and the state variables in the turning bow motion of the glider is established.(2)The steady-state spiral motion of an underwater glider controlled by two course control systems is simulated by using the Runge-Kutta method.The effects of different net buoyancy and pitch angles on course control are compared and analyzed through simulation results.Then maneuverability,economy and course tracking dynamic performance of internal attitude control system and stern rudder control system are compared and analyzed.(3)The fuzzy adaptive PID method is introduced to optimize the parameters of the existing PID control algorithm of the internal attitude adjustment system of the glider.Through the simulation comparison,the fuzzy adaptive PID method effectively improves the adaptive ability and anti-interference ability of the course control of the glider.(4)Through the comparison and analysis of sea trial data,the simulation accuracy of the influence of different control parameters on course control is verified.The course Angle under fuzzy PID control is more stable and the course control accuracy is higher.