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To improve the centroid extraction accuracy and efficiency of high-dynamic star sensors, this paper proposes a multi-centroid localization method based on the prior distribution of star trail projections. First, the mapping relationship between attitude information and star trails is constructed based on a geometric imaging model, and an endpoint centroid group extraction strategy is designed from the perspectives of time synchronization and computational complexity. Then, the endpoint position parameters are determined by fitting the star trail grayscale projection using a line spread function, and accurate centroid localization is achieved through principal axis analysis and inter-frame correlation. Finally, the effectiveness of the proposed method under different dynamic scenarios was tested using numerical simulations and semi-physical experiments. The experimental results show that when the three-axis angular velocity reaches 8°/s, the centroid extraction accuracy of the proposed method remains superior to 0.1 pixels, achieving an improvement of over 30% compared to existing methods and simultaneously doubling the attitude measurement frequency. This demonstrates the superiority of this method in high-dynamic attitude measurement tasks. [ABSTRACT FROM AUTHOR]

Reference-based super-resolution (RefSR) has achieved remarkable progress and shows promising potential applications in the field of remote sensing. However, previous studies heavily rely on existing and high-resolution reference image (Ref), which is hard to obtain in remote sensing practice. To address this issue, a novel structure based on a zoom camera structure (ZCS) together with a novel RefSR network, namely AEFormer, is proposed. The proposed ZCS provides a more accessible way to obtain valid Ref than traditional fixed-length camera imaging or external datasets. The physics-enabled network, AEFormer, is proposed to super-resolve low-resolution images (LR). With reasonably aligned and enhanced attention, AEFormer alleviates the misalignment problem, which is challenging yet common in RefSR tasks. Herein, it contributes to maximizing the utilization of spatial information across the whole image and better fusion between Ref and LR. Extensive experimental results on benchmark dataset RRSSRD and real-world prototype data both verify the effectiveness of the proposed method. Hopefully, ZCS and AEFormer can enlighten a new model for future remote sensing imagery super-resolution. [ABSTRACT FROM AUTHOR]

In this paper, the biaxial flexural mount is presented according to the requirements of the large aspect ratio mirror of an off-axis three-mirror anastigmatic (TMA) space-borne telescope, and the process of the optimal design of the flexural mount structure is discussed in detail. From the perspective of mechanics-based design of space-borne mirror assembly structure and integrated optical-mechanical analysis, the optimal axial mounting position, the optimal mounting angle and the optimal structural critical dimensions of the flexure hinge were determined to improve the surface shape accuracy. Finally, the mechanical vibration test further proved the rationality of the structure design and the accuracy of the simulation analysis. The flexural mount proposed in this paper is can be applied to other reflective optics with high surface figure requirements. The optimization method proposed in this paper can also be applied to the optimization of other forms of flexural mount. [ABSTRACT FROM AUTHOR]