Research On Key Technologies Of Airborne Image Stabilization Based On Fast Reflector

As an important load of aviation aircraft,the airborne image stabilization platform realizes scanning,detection,target recognition and tracking of target areas in various environments.With the development of science and technology,the stability and imaging of the airborne image stabilization platform Quality requirements are also increasing.The visual axis of the image stabilization platform is prone to deviation due to changes in the attitude of the aircraft,wind drag torque,or internal disturbance of the platform,and at the same time,high-quality images cannot be taken.Therefore,improving the platform’s boresight stabilization accuracy and performing image motion compensation are the keys to achieving high-precision airborne image stabilization.In this paper,aiming to stabilize the visual axis of the platform and high-quality imaging,a composite axis control scheme is proposed,and on this basis,the following three aspects of research work are carried out:(1)System analysis of airborne image stabilization platform.Including the work process of the image stabilization platform and the analysis of the main structure,the analysis of the main disturbance factors of the servo system in the working process.The coarse-stage stability control scheme is designed,and an adaptive robust sliding mode control method is proposed.Based on the motor model,the control law and the adaptive law are improved to meet the requirements of the coarse-stage stability when the fine-stage stability is achieved.(2)Design refined stability control scheme.Select self-developed fast mirrors and perform modeling to design Kalman filters.For the tuning of PID controller parameters,a genetic algorithm optimization scheme is proposed and the algorithm is optimized and improved.The improvement and optimization mainly include: the selection of the objective function adds the penalty function of variable weight,and the selection link adopts the random selection strategy without replay residue.Through experiments and simulation analysis,it is verified that the combination of the Kalman filter-based PID controller and genetic algorithm can effectively improve the dynamic performance of the fast reflector and ensure that the fast reflector can accurately compensate for the deviation of the visual axis and the image motion.(3)The theory of image motion compensation based on fast mirrors is analyzed.Analyze the causes of image motion and the necessity of image motion compensation.Determine the scanning imaging method.Establish a reference coordinate system and derive the angular velocity of the fast reflection mirror shift compensation.Finally,an experiment platform was built to carry out the experiments of visual axis stabilization and image motion compensation.Experimental results show that the system’s boresight stabilization accuracy has been increased by 5 times,and the system’s imaging resolution during image motion compensation is less than the minimum target limit that the system can resolve,which meets the needs of the project.