space remote sensing camera
- The Paper
Carbon fiber thin-walled cylindrical support structure between primary and secondary mirror in space camera
Abstract：In large-aperture and long-focus space remote sensing cameras， the relative position changes between the primary and secondary mirrors affect the imaging quality and stability of the camera. The support structure between the primary and secondary mirrors， that is the bearing structure between them， is integral for the camera design process. In this study， a carbon fiber thin-walled cylindrical support structure between the primary and secondary mirrors was designed， based on the characteristics of large-aperture and long-focus cameras. First， the cylindrical base structure was selected depending on the optical system considered. Then， based on the characteristics of the cylindrical base structure， the geometric structure of the secondary mirror support beam and the longitudinal reinforcement ribs of the cylindrical structure were analyzed and selected in sequence. Subsequently， to fully utilize the design characteristics of the carbon fiber material layup， the iterative design optimization of the key size of the support structure， thickness of the layup， and angle of the layup was performed， and the design results were analyzed by conducting finite element simulations. Finally， the stability and structural rigidity of the support structure were verified by measuring the change in the angle of the secondary mirror and conducting the characteristic-level sweep frequency vibration test. The results indicated that the differences in long-term monitoring under the same conditions for the secondary mirror was less than 1.5"， change before and after gravity flipping was less than 1.08"， first-order natural frequency of the supporting structure was greater than 115 Hz， and axial frequency was greater than 180 Hz. Thus， the support structure between the primary and secondary mirrors exhibited excellent rigidity and structural stability， satisfying the requirements of the design index.Keywords：space camera;primary and secondary mirror support structure;iterative optimization;structural stability685|1550|5
<HTML><L-PDF><WORD><Meta-XML>Updated：2026-09-11Application of metal rubber vibration absorber in coaxial dual-reflection space camera
Abstract：This paper presents a damped metal-rubber vibration absorber modeled on the response of a coaxial dual-reflection space camera to random vibration. First， we analyze the metal-rubber structure and develop a corresponding metal-rubber damper. We then use finite element analysis （FEA） to develop a model of the space camera and perform a modal analysis and random vibration response analysis of the model. Finally， we verify the accuracy of the FEA via a sinusoidal-sweep vibration test and a random-vibration test. The test results demonstrate that， in the X， Y， and Z directions， the first-order natural frequency of a coaxial dual-reflection space camera equipped with the metal-rubber damper exceeds 100 Hz； this frequency is beyond the natural frequency of the satellite. Hence， the camera will resonate with neither the satellite nor the ground sinusoidal sweep vibration. The response of the coaxial dual reflection space camera to excitation in the X， Y， and Z directions is 4.98grms in the random vibration test； the vibration responses of a secondary mirror in the X， Y and Z directions are 3.381grms， 2.884grms， and 1.969grms， respectively. After the vibration test， no evident aberration can be observed in the system. The damped metal-rubber vibration absorber has a significant damping effect on the space camera and has a patent.Keywords：space camera;metal rubber;vibration isolation;finite element analysis;random vibration579|1329|4<HTML><L-PDF><WORD><Meta-XML>Updated：2026-09-11Design of imaging model for cone-pendulum scanning integrated space camera
Abstract：Achieving super-wide coverage for high-resolution cameras is difficult. To address this difficulty， this study designs a cone-pendulum scanning integrated imaging mode. First， by analyzing the principle of cone-pendulum scanning integrated imaging， a cone-pendulum scanning integrated imaging model was established. Then， the optimal ground trajectory model was designed， and the relationship between the orbital velocity， angular velocity of the platform rotation， and angular velocity of the pendulum scanning rotation was analyzed. Simultaneously， based on the ground trajectory， a calculation scheme of exposure time and frame frequency was provided. Finally， MATLAB was used to perform simulations， and the ground coverage width and ground pixel resolution were analyzed. The results show that when the orbital altitude is 500 km， pixel size is 2.5 μm， focal length is 360 mm， and pixel number is 5 120×5 120， then the camera installation angle is 30°， number of frames of pendulum scanning imaging is 10， ground coverage width is 1 105.7 km， which is 31.1 times that of the image sub-satellite point push scanning imaging， and ground sample distance （GSD） is less than 6.4 m. The cone-pendulum integrated imaging mode can completely cover the ground target and considerably increase the width for specific resolutions.Keywords：space camera;imaging model;wide field imaging;geometric parameters;ground track637|1019|3<HTML><L-PDF><WORD><Meta-XML>Updated：2026-09-11Design of lightweight split support structure for large space off-axis three mirror camera
Abstract：According to the design requirements of lightweight and high-stiffness large-scale space camera frame support structures with a 1-m resolution and 200-km width， a lightweight split support structure is designed. In this study， a high-volume SiCp/Al composite material with good performance is selected based on the development requirements of a large space off-axis three-mirror camera， including the specific stiffness， thermal stability， and processing technology. Then， with the structure mass fraction as the constraint condition， a topology optimization mathematical model is established with the fundamental frequency as the objective function， and the optimal force transfer path of each split structure with clear topological results is obtained. The size of each part of the main support structure is optimized， and the optimal configuration and design size of each split structure are obtained. After the design， the total weight of the split support structure was 227.8 kg， and the lightweight rate reached 93.9%， which meets the requirements of high lightweight and stiffness. The results of finite-element analysis and mechanical prototype test show that the split support structure meets the stiffness requirements of the whole remote sensing camera with the fundamental frequency greater than 50 Hz， and the deformation of the mirror is within the tolerance range under the working condition of 5 °C， which fully satisfies the requirements of the satellite platform for optical loads. The mechanical prototype mirror assembly offset angle is less than 22° before and after the vibration test， showing its good stability， which proves the rationality and feasibility of the topology optimization and size optimization methods. The design of the proposed split support structure has a high engineering practice value for the support design of large space off-axis cameras.Keywords：large size space camera;topology optimization;split support;lightweight;size optimization1223|1872|9<HTML><L-PDF><WORD><Meta-XML>Updated：2026-09-11Adaptive compensation technique for CCD signal sampling positions in high-resolution remote sensing cameras
Abstract：Under the influence of temperature changes, the phase of the CCD sampling signal of a high-resolution remote sensing camera canvary.This canadversely affect the signal-to-noise ratio and dynamic range of the imageand may even cause the image to be displayedabnormally. To solve this problem of temperature-relatedsampling position drift, an adaptive compensation design was developed for the CCD sampling position of a high-resolution remote sensing camera. First, the initial position of the CCD sampling signal was precisely adjusted, and an adaptive compensation circuit was then designed tocontrol the power consumption, which rendered the temperature of each driver chipto be essentially the same. The advantage of this method is that the CCD and sampling signals can be effectively monitored during temperature changes, thus, ensuring the accuracy of the sampling position of the CCD signal and stability of the signal-to-noise ratio of the image. The experiments indicate that with this method, the accuracy of the initial position adjustment of the correlated double-sampling signal improves to less than 0.039 ns. Additionally, the maximum delay of the correlated double-sampling signal in the satellite in-orbit temperature range is 0.46 ns, which ensures high-quality imaging and meets the requirements of space applications.Keywords：high-resolution remote sensing cameras;Correlated Double Sampling(CDS);temperature;adaptive compensation435|384|3<HTML><L-PDF><Meta-XML>Updated：2020-08-13HDR imaging method of overcoming full well limitation for push-broom remote sensing cameras
Abstract：In order to increase the dynamic range of push-broom remote sensing cameras, An imaging method which applied the DTDI (Digital domain Time Delay Integration) technology with fixed integral stages and display method of HDR (High Dynamic Range) image was investigated in this paper. Firstly, the principle of DTDI was introduced. Secondly, by adopting the DTDI technology with fixed integral stage, the full well limitation could be overcome. Thus, a picture with higher image bit depth and larger dynamic range co Keywords：Complementary Metal Oxide Semiconductor(CMOS);Digital domain Time Delay Integration(DTDI);overcome the limit of full well;push-broom remote sensing cameras334|724|0<HTML><L-PDF>Updated：2020-07-05Evaluation and test of self-locking ability for focusing mechanism of space camera
Abstract：Focusing mechanisms in space camera needs to possess self-locking ability to resist the shock and vibration in the process of launching. Therefore, a self-locking analysis on the mechanism is the key of ensuring the space optics remote sensors work properly. This paper studied the sliding mechanism of thread contact surface under environments of vibration, and built a engineering models of the focusing mechanism of certain space camera with two types of screw pitch (1 mm, 1.5 mm). Contact stress, shear stre Keywords：space camera;focusing mechanism;self-lock;screw thread;random variation528|867|0<HTML><L-PDF>Updated：2020-07-05Optical imaging technology of JL-1 lightweight high resolution multispectral remote sensing satellite
Abstract：In order to realize light-weight design as well as multi-spectral and multi-mode imaging with high resolution of JL-1 optical remote sensing satellite, advanced integration design method and payload centric concept were adopted, thus indexes, scheme and key techniques of JL-1 were given and in-orbit multi-mode optical imaging was achieved. The mass of JL-1 is approximately 450 kg, the payload ratio reaches 40% and the attitude maneuver speed of JL-1 can be 2.1 (°)/s, which enable stereo and piece imaging. With the capacity of 800 GB on-board FLASH storage and double X band 600 Mbps telemetry, JL-1 satellite can collect up image data over nearly 150, 000 km2 daily. The satellite was launched in 2015, and can collect images with resolutions of 0.72 m (PAN) and 2.88 m (MS) in 656 km sun synchronous orbit, which meet the requirements of commercial movements.Keywords：optical remote sensing;platform and payload integration;JL-1;multi-mode imaging;lightweight high-resolution1218|1143|0<HTML><L-PDF>Updated：2020-07-07Study and test of thermal-defocusing property in space camera
Abstract：In order to improve the image quality of space camera in different temperature fields, a integrated analysis model of structure-thermal-optical performance (STOP) model was established. According to the model, the thermal-defocusing property of the system was studied and test, and focusing curve of camera temperature was obtained. Then, thermo-optical experiment was developed. Firstly, influence of temperature changes on optical system, especially influence on optimal image plane position, was analyzed to o Keywords：space camera;integrated analysis;temperature focusing;finite elements;thermo-optical test451|835|0<HTML><L-PDF>Updated：2020-07-07Design and optimization of carbon fiber framework for space camera
Abstract：In this paper, a CFC framework applied to light-small space camera was designed. Selected, through comparison, the M40J carbon fiber composite with excellent structural performance and processing property to complete structural design of the camera framework based on spatial distribution characteristics of each optical element in the optical system, and then used TC4 embedded parts to solve the problem of low interface accuracy of CFC framework; carried out regional division in the CFC framework, and then c Keywords：framework of space camera;carbon fiber composite;integrated optimization;combined optimization strategy600|1023|0<HTML><L-PDF>Updated：2020-07-07
