Research On Shipboard Camera Stabilization Platform Based On Composite Control

With the rapid development of information technology industry,video surveillance technology has been widely used in public security,transportation,electricity,banking and many other fields,and gradually extends outward.Among them,the demand for video surveillance security on mobile carriers such as vehicle,airborne and shipborne has also become a hot research topic.In this thesis,the shipborne camera stabilization platform is taken as the main research object,focusing on the stability of the shipborne camera platform,so as to ensure that the shipborne camera can maintain a stable state when the ship is swayed by random waves.Firstly,the overall functional analysis is carried out for the shipboard camera stabilization platform,and the mechanical stabilization technology of the three-axis stabilization platform structure is determined in this thesis,and the overall control scheme of the stabilization platform is designed with three-closed-loop(current loop,velocity loop and position loop)control method is adopted,and the preliminary modeling analysis is carried out with the brushless DC motor selected for this topic.Secondly,in view of the ship as the camera moving carrier,the random wave signals are firstly simulated and analyzed,and then the roll and pitch motion generated by the ship in the random wave are simulated and analyzed,and the roll and pitch motion of the ship is further predicted and analyzed.In the prediction,the analysis is mainly carried out through three methods: Firstly,BP neural network algorithm and random forest(RF)algorithm were used to predict ship roll and pitch motions respectively.Then,in order to further improve the prediction accuracy,a combination of BP neural network and random forest method was proposed to predict ship motion.Then,the specific control strategy of the stable platform is studied.In the three-closed-loop control system,the current loop and speed loop are controlled by simple PI,and the position loop is controlled by PID.The feasibility is proved by simulation.However,in order to improve the control accuracy,a compound control strategy is proposed in the position loop,which adopted the two-degree-of-freedom internal model control based on flower pollination optimization and added the feedforward control based on BP-RF ship attitude prediction.Simulation results show that this strategy can effectively improve the control accuracy.Finally,combined with the above ship attitude prediction method and platform control strategy,the software and hardware are described in detail.Select related hardware according to the functional requirements of the shipboard camera stabilization platform,and complete the design of related schematic diagrams and PCB boards;The upper computer program based on Visual Studio software is prepared to realize the interaction between the upper computer and the lower computer.And the experimental test shows that the control precision of the three-axis stable platform meets the needs of the project.