Research On Control Of Unmanned Multibeam Adaptive Platform

Due to the influence of wind and waves on the sea surface,the unmanned vessel loaded with multibeam detection device is prone to produce a large deflection,this results in data distortion.Aiming at the problem,this paper intends to study a rack structure that can be loaded with multibeam devices,according to the deflection direction and angle of the unmanned aerial vehicle,adaptively adjust its movement,so that the multibeam can always detect vertically downward.The traditional self-adaptive frame adopts the structure of two axis vertical shafting with orientation and height,when the unmanned vessel is subjected to wind waves parallel to the height axis,its azimuth axis must rotate 90° immediately,which may easily lead to the vibration of the frame,even out of control.The angle between the azimuth axis and the oblique axis is 45°,the movement in the height direction is caused by the rotation of the oblique axis on the intersection of the two axes,it can effectively overcome the vibration of traditional structure,and it brings new hope for the stable pointing control of multibeam device.However,the non-orthogonal axis structure of the oblique shaft frame,so that there is kinematic coupling(KC)between the movements along the two axes,it presents a complex non-linear structure.Therefore,it is necessary to analyze the dynamic principle of this kind of frame structure,puts forward feasible control plan,and then solve the precise pointing problem of the rack.Aiming at the non-linear structure of the oblique shaft frame,first analyzes its dynamic characteristics,through trajectory planning,establish the relationship between the direction and angle deviation caused by the deflection of the unmanned ship structure and the vertical direction;and the simulation model is built to further verify the correctness of the planning results.When the deflection of the multibeam detection device occurs,the rotation angle required for the azimuth axis and the oblique axis can be determined through trajectory planning,so that the multibeam device can maintain a stable vertical downward direction.Second,build a two-axis drive system simulation model,construct a control method that combines trajectory planning and dynamic PID,the feasibility of the control is verified by simulation.Finally,the software and hardware system of the adaptive oblique axis frame is built,the stable pointing ability of the frame is verified by experiments,and further optimized.The experimental results show that when the deflection angle of unmanned vessel is less than 60°,the adaptive frame can make the multibeam device keep stable vertical detection without distortion,ensure the detection accuracy of unmanned vessel.Therefore,it is feasible to use the oblique axis frame in the adaptive pointing control of unmanned multibeam device,and it has certain reference value for the high performance detection of the unmanned vessel in our country.