摘要
在对空间碎片进行分析研究中,大视场的天基目标探测载荷成为提高探测效率的有效方式,在实际成像过程中,由于曝光时间长,加上卫星自身在轨姿态的运动、二维转台的转动等因素,会导致空间相机在图像上产生像旋。通过齐次坐标变换法对像旋进行分析,得出相机存在±2′的像旋,并利用柔性单元和压电驱动器设计了一种新型无摩擦、无磨损、免润滑的像旋补偿机构,带动空间相机反方向的旋转对像旋进行补偿。然后对柔性单元应力和系统固有频率进行优化设计,推导柔度公式和精度公式,并对结果进行有限元仿真分析。结果表明:仿真结果与理论计算模型的最大相对误差均小于5%,该机构能够实现大视场空间相机的像旋补偿,并且具有较高的精度。
Objective Space-based target detection is the main way to observe space debris.In recent years,with the gradual increase of space debris,it is difficult for small field of view space cameras to meet the observation needs,and the use of large field of view space cameras is increasing.During the observation of space debris,due to the orbital motion of the satellite itself and the motion of the two-dimensional turntable,the image rotation will occur in the imaging of the large field of view space camera,especially when observing dim targets,the camera's exposure time will increase,and the generated image rotation will also increase.It seriously affects the accuracy of recognition and reduces the efficiency of large field of view space camera.Therefore,image rotation compensation must be carried out for large field of view space camera.Methods In order to determine the performance index of image rotation compensation,the imaging coordinate system of the system is established(Fig.1),and the image rotation of the system is calculated by the homogeneous coordinate change method.According to the performance index of image rotation compensation,a new type of image rotation compensation mechanism based on the inner and outer rings of symmetrical right straight circular flexure hinge is proposed(Fig.3).Then,the flexibility and accuracy formula of the flexible element of the image rotation compensation mechanism is deduced according to the second theorem of Cassegrain,and the relationship between the flexibility and the structure size is analyzed.Then,the image rotation compensation structure is optimized by genetic algorithm.Finally,the static and modal analysis of the image rotation compensation mechanism is carried out by simulation(Fig.11,12,14),and it is verified by experiments.Results and Discussions By analyzing and calculating the±2′image rotation of a large field of view space camera,an image rotation compensation mechanism composed of eight completely symmetrical flexible elements is designed for the image rotat
作者
刘树迪
田海英
邵建兵
Liu Shudi;Tian Haiying;Shao Jianbing(Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences,Changchun 130033,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《红外与激光工程》
EI
CSCD
北大核心
2023年第7期243-254,共12页
Infrared and Laser Engineering
基金
吉林省科技发展计划重点研发项目(20210201090GX)。
关键词
大视场空间相机
像旋补偿
柔度矩阵
固有频率
large field of view space camera
image rotation compensation
flexibility matrix
natural frequency
