Design of high precision star image locating method used in star sensor technology

In order to meet the high precision calibration requirements of precision angular distance and high magnitude to the optical navigation sensor, A new style of high precision star simulator with large caliber, and long-focus, is presented. And then the main compositions of this simulator are designed in detail referring to the simulator, the steering mirror, the standard simulated targets and so on. According to the simulator characteristics of large size lens and multi lens, the structural of lens cone uses the tube sleeve and inner sleeves fixed together means. To eliminate the mirror deformation, the design plan based on the tiny stress is applied in steering mirror. In order to achieve a high magnitude, the light targets are simulated by optical transmission from OLED to high precision drone with fibers. Its degree ≤1〞,simulated magnitude≥5 that meet calibration requirements of the current high-precision optical navigation sensor.

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High precision automatic measurement for alignment of camera and star-sensor in GF-2

Optics and Precision Engineering ◽

10.3788/ope.20172511.2931 ◽

2017 ◽

Vol 25 (11) ◽

pp. 2931-2938 ◽

Cited By ~ 2

Author(s):

孙刚 SUN Gang ◽

杨再华 YANG Zai-hua ◽

万毕乐 WAN Bi-le ◽

张成立 ZHANG Cheng-li ◽

代卫兵 DAI Wei-bing

Keyword(s):

High Precision ◽

Automatic Measurement ◽

Star Sensor

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Optical Parameters Optimization for All-Time Star Sensor

Sensors ◽

10.3390/s19132960 ◽

2019 ◽

Vol 19 (13) ◽

pp. 2960

Author(s):

Wang ◽

Wei ◽

Li ◽

Du ◽

Zhang

Keyword(s):

High Altitude ◽

Background Radiation ◽

Imaging System ◽

Model Simulation ◽

Parameters Optimization ◽

Sensor Technology ◽

Optical Parameters ◽

Star Sensor ◽

Cost Constraints ◽

Sensor Detection

As an important development direction of star sensor technology, the All-Time star sensor technology can expand the application of star sensors to flight platforms inside the atmosphere. Due to intense atmospheric background radiation during the daytime, the commonly used star sensors operating in the visible wavelength range are significantly limited in their ability to detect stars, and hence the All-Time star sensor technology which is based on the shortwave infrared (SWIR) imaging system has become an effective research direction. All-Time star sensor detection capability is significantly affected by observation conditions and, therefore, an optimized selection of optical parameters, which mainly includes the field of view (FOV) and the detection wavelength band, can effectively improve the detection performance of All-Time star sensors under harsh observation conditions. This paper uses the model simulation method to analyze and optimize the optical parameters under various observation conditions in a high-altitude environment. A main parameter among those discussed is the analysis of detection band optimization based on the SWIR band. Due to the huge cost constraints of high-altitude experiments, we conducted experiments near the ground to verify the effectiveness of the detection band selection and the correctness of the SWIR star sensor detection model, which thereby proved that the optimization of the optical parameters for high altitudes was effective and could be used as a reference.

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Star Image Prediction and Restoration under Dynamic Conditions

Sensors ◽

10.3390/s19081890 ◽

2019 ◽

Vol 19 (8) ◽

pp. 1890 ◽

Cited By ~ 3

Author(s):

Liu ◽

Chen ◽

Liu ◽

Shi

Keyword(s):

Attitude Control ◽

Attitude Determination ◽

Back Propagation ◽

Prediction Method ◽

Back Propagation Neural Network ◽

Attitude Measurement ◽

Star Sensor ◽

Dynamic Conditions ◽

Star Image ◽

Image Prediction

The star sensor is widely used in attitude control systems of spacecraft for attitude measurement. However, under high dynamic conditions, frame loss and smearing of the star image may appear and result in decreased accuracy or even failure of the star centroid extraction and attitude determination. To improve the performance of the star sensor under dynamic conditions, a gyroscope-assisted star image prediction method and an improved Richardson-Lucy (RL) algorithm based on the ensemble back-propagation neural network (EBPNN) are proposed. First, for the frame loss problem of the star sensor, considering the distortion of the star sensor lens, a prediction model of the star spot position is obtained by the angular rates of the gyroscope. Second, to restore the smearing star image, the point spread function (PSF) is calculated by the angular velocity of the gyroscope. Then, we use the EBPNN to predict the number of iterations required by the RL algorithm to complete the star image deblurring. Finally, simulation experiments are performed to verify the effectiveness and real-time of the proposed algorithm.

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Noise suppression algorithm of short-wave infrared star image for daytime star sensor

Infrared Physics & Technology ◽

10.1016/j.infrared.2017.08.002 ◽

2017 ◽

Vol 85 ◽

pp. 382-394 ◽

Cited By ~ 10

Author(s):

Wenjie Wang ◽

Xinguo Wei ◽

Jian Li ◽

Gangyi Wang

Keyword(s):

Noise Suppression ◽

Short Wave ◽

Star Sensor ◽

Star Image ◽

Infrared Star ◽

Short Wave Infrared

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Region-confined restoration method for motion-blurred star image of the star sensor under dynamic conditions

Applied Optics ◽

10.1364/ao.55.004621 ◽

2016 ◽

Vol 55 (17) ◽

pp. 4621 ◽

Cited By ~ 14

Author(s):

Liheng Ma ◽

Franco Bernelli-Zazzera ◽

Guangwen Jiang ◽

Xingshu Wang ◽

Zongsheng Huang ◽

...

Keyword(s):

Star Sensor ◽

Dynamic Conditions ◽

Star Image ◽

Restoration Method

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Precise Attitude Determination of Ship Based on Star Sensor

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.380-384.995 ◽

2013 ◽

Vol 380-384 ◽

pp. 995-1002 ◽

Cited By ~ 2

Author(s):

Bing Liu ◽

Feng Chen ◽

Tong Shuang Zhang ◽

Dean Zhong ◽

Lei Yang ◽

...

Keyword(s):

Engineering Design ◽

High Precision ◽

Attitude Determination ◽

Measured Data ◽

Star Sensor ◽

Single Star

This paper analyses the attitude measured model and presents the attitude determination algorithm of space TT&C ship (space tracking, telemetry, and command ship) based on single star sensor. Considering lower precision of rolling angel for single star sensor, we proposed an algorithm by integrating attitude determination and redundancy measure to obtain high precision ship attitude data. Aiming at the circumstance of space TT&C ship, the factors that influence the precision of attitude measured data such as the number of star, atmosphere refraction correct and installation elevation are analyzed, which this can provide valuable references to the engineering design for star sensor used on space TT&C ship.

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Motion Blurred Star Image Restoration Based on MEMS Gyroscope Aid and Blur Kernel Correction

Sensors ◽

10.3390/s18082662 ◽

2018 ◽

Vol 18 (8) ◽

pp. 2662 ◽

Cited By ~ 6

Author(s):

Shiqiang Wang ◽

Shijie Zhang ◽

Mingfeng Ning ◽

Botian Zhou

Keyword(s):

Image Reconstruction ◽

Motion Blur ◽

Reconstruction Method ◽

Motion Trajectory ◽

Star Sensor ◽

Mems Gyroscope ◽

Structure Information ◽

Star Image ◽

Image Reconstruction Method ◽

Blur Kernel

Under dynamic conditions, motion blur is introduced to star images obtained by a star sensor. Motion blur affects the accuracy of the star centroid extraction and the identification of stars, further reducing the performance of the star sensor. In this paper, a star image restoration algorithm is investigated to reduce the effect of motion blur on the star image. The algorithm includes a blur kernel calculation aided by a MEMS gyroscope, blur kernel correction based on the structure of the star strip, and a star image reconstruction method based on scaled gradient projection (SGP). Firstly, the motion trajectory of the star spot is deduced, aided by a MEMS gyroscope. Moreover, the initial blur kernel is calculated by using the motion trajectory. Then, the structure information star strip is extracted by Delaunay triangulation. Based on the structure information, a blur kernel correction method is presented by utilizing the preconditioned conjugate gradient interior point algorithm to reduce the influence of bias and installation deviation of the gyroscope on the blur kernel. Furthermore, a speed-up image reconstruction method based on SGP is presented for time-saving. Simulated experiment results demonstrate that both the blur kernel determination and star image reconstruction methods are effective. A real star image experiment shows that the accuracy of the star centroid extraction and the number of identified stars increase after restoration by the proposed algorithm.

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