Research On The Strategy And Method Of UUV Landing Control

Unmanned Underwater vehicle(UUV)have become a powerful tool in Marine scientific investigation as well as underwater target investigation and rescue.With the development of Marine environment,the great prospect of UUV is showning.However,under the restriction of energy,UUV can not work for a long time at present.In order to extend the working time under limited energy,this paper studies the strategy and control methods of UUV underwater landing.Analyzed the UUV's function required and environmental constraints,combined with the problems in the actual process of underwater landing,a control strategy,and several key problems in the process is detailed researched.This paper mainly discusses the following aspects:Firstly,the function of UUV seat is considered by means of energy,navigation and environmental disturbance.Considering the safety and stability of the underwater landing.,the constraint conditions of the underwater landing.are obtained.According to the functional requirements of the landing type UUV,the structure of the system is given,and the underwater landing strategy and control flow are designed according to the characteristics of the seated tasks.Secondly,based on the selection of the landing position,the construction method of seabed topography based on multi-beam sonar is designed.By sailing with the comb like track near the bottom of scheduled landing area,UUV can detect the terrain ups and downs using multi-beam sonar.after processing of detection data construct by regional terrain elevation model,and then based on the terrain elevation model building,by measuring the height of the local area and degree to select a relatively flat area,the center as a landing position.Thirdly,the mathematical model of the landing type UUV is established.In the background of plane position keep under the current,according to the coordinate system transformation relationship gives the kinematics model of UUV.In reference of submarine's dynamic model,according to the characteristics of the landing type UUV,A dynamics model and the thrust allocation relationship is established.Then,in order to solve the problem of the effect of the ocean current in the process of UUV leading,it is difficult to land on a predetermined position.On the analysis of the sliding mode robust control for the applicability of the UUV posture control,according to lyapunovstability theory,designed the heading controller and the dynamic position controller based on sliding mode robust control.For the problem of buoyancy distribution caused by pressure after deep diving,combined with vertical thruster control quickness and buoyancy adjusting control of sustainability,we design a vertical thrusters and buoyancy adjusting device under the joint control of static force disturbance UUV trim control method.The effectiveness of the controller is verified by simulation experiment.Finally,the control in the process of UUV underwater leading task including diving,terrain detection,location keep,variable buoyancy landing process is combined and designed the negative buoyancy diving,terrain detection and bottom location selection sa well as the dynamic change of buoyancy landing process simulation case,results show that the control strategy and control method can effectively control the UUV underwater landing mission.