Research On Visual Axis Stability Control Method Of Shipborne Laser Communication Terminal

The shipborne laser communication visual axis servo system is an important part of the shipborne laser communication platform.It is mainly responsible for establishing a stable communication link between the transmitting and receiving sides.However,in a complex marine environment,the ship-based visual axis servo platform faces many disturbance factors: the influence of waves,winds,currents on the platform,and the vibration and noise inside the platform,which will cause great impact on the laser communication method using the point-to-point mode.The visual axis cannot be precisely aligned,resulting in low communication quality or even communication interruption.Therefore,in order to realize the visual axis with precise alignment,the dynamic boresight can stably track dynamic targets,and relevant control strategies must be adopted to suppress the disturbance of the carrier platform..This paper first introduces the substructure and working principle of the shipborne laser communication platform,and makes a detailed analysis of the structure in the visual axis servo system,that is,the attitude data of the carrier platform is obtained according to the sensors such as the gyro,and the rough tracking execution structure is assigned.The visual axis and the aiming operation are performed,and on this basis,fine tracking is used to achieve a smaller range and higher precision pitch and azimuth angle fine adjustment.The internal and external disturbance factors of the shipboard platform are analyzed,and its influence on the stability performance of the shipboard platform is explained.The relevant theoretical framework is prepared in advance to lay the foundation for the next disturbance calculation.Secondly,for the shipborne platform of complex marine environment,the coordinate system is used to analyze the change of the attitude of the sea to the hull,and the angular displacement of the visual axis caused by the force of the wave is gradually obtained,and the dynamic model of the shipboard platform is established.The circuit characteristics of the visual axis servo control system are established,and the electromechanical models are established,and the simulation analysis is carried out separately.Then,in view of the complex disturbance of the ship-based visual axis servo system,an improved Linear Active Disturbance Rejection Control method is designed in this paper.The stability and anti-interference ability of the control algorithm are analyzed step by step.The simulation experiment proves the strong anti-interference ability and error isolation effect of the Linear Active Disturbance Rejection Control method under the complex disturbance of shipboard,which is suitable for the control method of the relevant carrier visual axis.Finally,a simulated shipboard experimental system was established,and relevant simulation experiments were carried out for the tracking stability of the ship-borne laser communication terminal.After the attitude information measured by the GPS and the gyroscope is converted in real time,the angle at which the torque motor needs to be rotated is obtained,and the visual axis offset of the disturbance action is compensated in real time by the controller.The experimental results show that the stability control technology meets the accuracy requirements of the visual axis tracking,has good tracking performance,can realize the stable establishment of the shipborne laser communication link,and verifies the applicability and stability of the control algorithm in the visual axis tracking process.