Application Of Genetic Algorithm PID Control In AUV Attitude Adjustment

Autonomous underwater vehicle(AUV)is the most important branch of underwater robot(UUV),because it can complete tasks in the underwater movement,so it is also the most popular research direction of underwater robot.The new underwater vehicle mentioned in this paper is a new type of underwater vehicle developed by our laboratory.Its tail four propellers are arranged in an x-shape with no rudder propeller.Through the control of the tail four propellers and the flow deflector,the flexible movement of the vehicle can be realized.It changes the buoyancy by changing the amount of water sucked into the pressure chamber,and at the same time changes the position of the center of gravity.It takes its own high-energy battery as the main power source,and is equipped with forward-looking obstacle avoidance sonar,side-scan sonar,water velocity meter,etc.,which can accurately observe the underwater situation.Compared with most under-actuated torpedo uuv designs,this new uuv has a much smaller turning radius,stable and reliable operation,flexible movement,long endurance and other characteristics,and can be applied to the exploration of Marine resources and military fields with broad prospects.Firstly,this paper gives a general introduction of auv,including its development history,basic classification,research status at home and abroad,specific application and future development trend.Then the structure and working principle of the new underwater robot are introduced,and its dynamic model is established on the basis of vector matrix method,momentum theorem and rigid body rotation theorem,etc.This paper wants to design the genetic algorithm PID controller,before this first to the genetic algorithm,including the development of the genetic algorithm,basic theoretical knowledge,standard genetic algorithm and its improvement,but also introduced the basic PID control theory and method.After that,the PID controller based on genetic algorithm was designed on the basis of the previously established dynamic model.Since the underwater situation would change,the PID control alone could not adapt to this change.After the research on the underwater situation,it was found that the PID control based on genetic algorithm had a good effect.Respectively control the change of the four screw speed,can realize the robot's pitch and deflection,secondly according to the design of the controller in Matlab to process of pitch and deflection are simulated,the results show that the genetic algorithm parameters reasonable choice under the adjustment of PID parameters setting is also very reasonable,and has a smaller system overshoot and verify the effectiveness of the controller.At last,the towing tank and qiandao lake are tested respectively,and the data are analyzed and studied after several tests to further improve the performance of the controller.