Research On Structural Design And Active Vibration Reduction Methods Of Aerial Remote Sensing System Vibration Reduction Platform

Aerial remote sensing system is widely used in military reconnaissance,terrain mapping,disaster monitoring and other fields.Aerial camera,as the main component of aerial remote sensing system,its imaging quality is an important indicator of detection results.During the aerial photography task of aerial camera,aircraft vibration is one of the important factors to reduce the imaging quality of aerial camera.Suppressing the influence of vibration on the imaging quality of aerial camera is an important research direction in the field of aerial remote sensing.Therefore,this paper takes TDICCD aerial camera as the research object,studies the influence of vibration on the imaging quality of aerial camera,designs a vibration reduction platform for aerial remote sensing system through the analysis of visual axis pointing error of aerial camera,establishes an active vibration reduction method and carries out experimental research.Firstly,the visual axis pointing error caused by aircraft vibration is modeled and analyzed.The influence of aircraft vibration on the visual axis pointing of aerial camera is studied.Based on the spatial coordinate transformation model of linear vibration and angular vibration,a composite visual axis pointing model is established,and the visual axis pointing error caused by aircraft vibration is simulated and analyzed,which provides a theoretical basis for the design of vibration reduction platform.Secondly,based on the visual axis pointing model of aerial camera,a three-dimensional model of vibration reduction platform for aerial remote sensing system is designed.The model adopts multi-stage flexure hinge structure as connecting parts,and studies the influence of parameters such as long semi-axis,short semi-axis and minimum thickness of elliptical arc in flexure hinge on the natural frequency of vibration reduction platform for aerial remote sensing system,and designs a vibration reduction platform suitable for aerial remote sensing system.Then,an active vibration reduction method based on BP neural network algorithm is designed and optimized by sparrow search algorithm.The actual aircraft vibration data are trained and predicted by using this method.The predicted signal is used as the input reference signal of actuator for vibration reduction platform to realize active suppression of aircraft vibration.The prediction results of active vibration reduction method before and after optimization are compared by simulation analysis.The results show that the accuracy and convergence speed of optimized vibration reduction method are significantly improved.Finally,in order to verify the vibration reduction effect of the platform,Propose a ground detection method for long focal length linear array aerial cameras based on image width variation.Based on the imaging results of TDICCD aerial camera,this method collects light bar images of dividing plate,establishes image quality evaluation model under vibration influence,and verifies the vibration reduction effect of platform based on this model.The experimental results show that the vibration reduction platform for aerial remote sensing system significantly reduces the influence of vibration on the imaging quality of aerial camera.This article establishes a composite aircraft vibration line of sight pointing error model,and designs an aviation remote sensing system vibration reduction platform based on this.Through simulation analysis and experimental testing,the reliability of the vibration reduction platform is verified.An active vibration reduction method based on BP neural network was established for the designed vibration reduction platform,and the sparrow search algorithm was used to optimize the initial weights and thresholds.A ground detection method for long focal length linear array aerial cameras based on image width variation was proposed,and the performance of the damping platform was tested using this method.The experimental results show that under vibration conditions of 100Hz～200Hz and sampling frequency of 5000 Hz for aerial cameras,the maximum angular vibration amplitude is reduced by 80%,achieving active vibration suppression.