The Design Of Small Airborne Camera Stabilization Platform And Its Influence On Image Quality

In the process of aerial photography and aerial survey,the aircraft is equipped with a camera.In order to get good photographs.It is necessary to ensure that the camera's visual axis is stable and consistent with the vertical direction of the inertial space.But when the plane was disturbed or the plane adjust its attitude,the camera's axis may shift and doesn't stay vertical in the inertial space.So the imaging quality will be affected.At this time,it can be used to improve the imaging quality by optimizing imaging optical system or the image post-processing.In another way,a stabilized platform can be installed between the camera and the plane to improve the quality of imaging.When install the camera in the stabilized platform,the movement of the camera and camera visual axis Angle relative to the vertical direction of the inertial space can be get by the sensors on the stabilized platform.Then the perceived signals are transmitted to the control part.The control part make the motor move to drive the shafting of the stabilized platform so that it can compensate for the movement of the camera accordingly and keep the camera visual axis steady in the vertical direction of the inertial space.This can effectively improve the imaging quality of the camera and facilitate the post-processing of images by the staff.Many foreign countries have studied the camera stabilized platform and got a good grade.For example,the PAV series stabilized platform designed and produced by Leica in Switzerland,GSM3000 designed and produced by German companies and T-AS designed and produced by American companies.These products have high accuracy and good performance.However,the foreign stabilized platform is not versatile,and the control interface is not open,which can not completely meet the requirements of high precision imaging in China.The stabilized platform has a greater influence on the accuracy of camera imaging quality,the higher accuracy of the stabilized platform needs the higher precision of the sensor,the high precision sensor leads to a corresponding larger volume.However,the smaller the stabilized platform is,the easier it is to install the stabilized platform on the plane.Therefore,the improvement of the stability platform's overall accuracy and miniaturization are the main trend of development and the focus of this design.Firstly,it makes a design of the overall structure of the stabilized platform in this paper,and the stabilized platform adopts the three-axis three-frame structure.The design and analysis of the shafts of the stabilized platform ensure that the structure and dimension of the stabilized platform meet the design and use requirements.And the motors are selected to ensure the stabilized platform can realize the corresponding movement.Among them,the azimuth ring of stabilized platform adopts the dense ball bearing,which can not only improve the precision of the stabilized platform but also save space effectively.Secondly,the precision distribution and calculation of the stabilized platform are carried out in this paper.Stabilized platform is divided into three directions for research,and in every direction,the reasonable selection of sensor precision,the machining precision and assembly precision,finally ensure the accuracy of the camera optical axis pointing to within 0.050 °.Thirdly,the structure of the stabilized platform is analyzed.Static analysis,modal analysis,random vibration analysis and impact vibration analysis are carried out on the stabilized platform.The structure of the stabilized platform has certain strength and stiffness,which can meet the work requirements under load and vibration interference.Finally,it analyzes the stabilized platform's influence on the camera image quality in this paper.when used the stabilized platform which pointing accuracy is 0.050 °,can effectively reduce the object distance,improve the definition and can completely meet the accuracy requirement for aerial photography and aerial survey.It guarantee the pointing precision of the stabilized platform is 0.050 ° by designing the mechanical structure of the stabilized platform and distributing its precision in this paper.The finite element analysis of the stabilized platform ensures that the stabilized platform has sufficient strength and stiffness to meet the requirements of use.By analyzing the influence on imaging quality,after carrying stabilized platform can be concluded that,the stabilized platform designed in this paper can effectively enhance camera resolution and camera image quality can be improved.