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Exposure Time Optimization for Highly Dynamic Star Trackers

Xinguo Wei, Wei Tan, Jian Li, Guangjun Zhang
2014 Sensors  
This paper focuses on how exposure time affects the star tracker under highly dynamic conditions and how to determine the most appropriate exposure time for this case.  ...  Under highly dynamic conditions, the star-spots on the image sensor of a star tracker move across many pixels during the exposure time, which will reduce star detection sensitivity and increase star location  ...  The second author Wei Tan has performed the simulations and analysis, while the third author Jian Li has performed the night sky tests using a real star tracker and collected the experimental data.  ... 
doi:10.3390/s140304914 pmid:24618776 pmcid:PMC4003974 fatcat:qwq2oxlaene67p7otop4qwjrce

Application of APS arrays to star and feature tracking systems

Christopher C. Clark, Orly Yadid-Pecht, Eric R. Fossum, Phil M. Salomon, Edwin W. Dennison, E. Kane Casani, Mark A. Vander Does
1996 Space Sciencecraft Control and Tracking in the New Millennium  
The Jet Propulsion Lab (JPL) is developing advanced concepts for future spacecraft celestial trackers by incorporating active pixel sensor (APS) array technology into star and feature tracker designs.  ...  A new star and feature tracker concept enabled by this regional shuttering capability is described.  ...  Regional shuttering capability dramatically increased the effective dynamic range of trackers and enables a means for optimizing image signal-to-noise level in real-time.  ... 
doi:10.1117/12.255130 fatcat:7rjk6ddezbbw3jmtjqtgkbgpqu

Centroid error compensation method for a star tracker under complex dynamic conditions

Wenfeng Tan, Shiqiao Qin, R. M. Myers, T. J. Morris, Guangwen Jiang, Yingwei Zhao, Xingshu Wang, Liheng Ma, Dongkai Dai
2017 Optics Express  
Dongkai (2017) 'Centroid error compensation method for a star tracker under complex dynamic conditions.  ...  However, the star centroid is shifted from the star true position at the center time of the exposure period under complex dynamic conditions, which is called the complex motion induced error (CMIE) in  ...  Introduction As an absolute attitude determination device, a star tracker can provide highly accurate attitude information for vehicles e.g. satellites, ballistic missiles and ships etc.  ... 
doi:10.1364/oe.25.033559 fatcat:mwrdo3dfejesfjrbruzopmp6he

An Efficient and Robust Star Identification Algorithm Based on Neural Networks

Bendong Wang, Hao Wang, Zhonghe Jin
2021 Sensors  
Furthermore, its identification time is as short as 32.7 miliseconds and the memory required is about 1920 kilobytes. The algorithm proposed is suitable for current embedded systems.  ...  Experiments show that the proposed algorithm is highly robust to position noise, magnitude noise, and false stars.  ...  Robustness to Rotation Velocity of the Star Tracker When star tracker works under dynamic condition, the rotation of the star tracker will cause the star image to elongate during exposure time, causing  ... 
doi:10.3390/s21227686 pmid:34833762 pmcid:PMC8620066 fatcat:cnybw25ykvaqvazkvbpkonely4

Development Of Star Tracker For Satellite

S. Yelubayev, V. Ten, B. Albazarov, E. Sarsenbayev, К. Аlipbayev, A. Shamro, Т. Bopeyev, А. Sukhenko
2015 Zenodo  
It is planned to use the results of this project for development of star tracker prototype in the future. This article describes the main stages of development of star tracker experimental model.  ...  Many projects related to the development of components for satellite are carried in Kazakhstan, in particular the project related to the development of star tracker experimental model.  ...  INTRODUCTION TAR tracker is a high-tech device for highly accurate attitude determination of satellite.  ... 
doi:10.5281/zenodo.1099819 fatcat:cr7sgrliejhtff4444g54zzrg4

A Compressed and High-Accuracy Star Tracker with On-Orbit Deployable Baffle for Remote Sensing CubeSats

Xinyuan Liu, Fei Xing, Shaoyan Fan, Zheng You
2021 Remote Sensing  
In order to reduce the volume of star tracker without compromising the performance, the relationship between the volume and pointing accuracy or dynamic performance is studied and an optimization model  ...  The deployable star tracker has almost the same results on stray light suppression ability, pointing accuracy (better than 3″ (3σ)) and dynamic performance (up to 3°/s) with the traditional star tracker  ...  of the lens and denotes the exposure time of the detector.  ... 
doi:10.3390/rs13132503 fatcat:qdmbmw32crcnhh5s436jdmyuby

Star trackers for attitude determination

C.C. Liebe
1995 IEEE Aerospace and Electronic Systems Magazine  
Finally the commercial market for star trackers is discussed.  ...  The instruments are called star trackers and they are capable of determining the attitude with an accuracy better than 1 arcsecond. The concept of the star tracker is expfained.  ...  An important aspect in determining the exposure time is whether the spacecraft is 2. or 3 axis stabilised. Also the S/N ratio will decrease with increasing exposure time.  ... 
doi:10.1109/62.387971 fatcat:5kfzjg75e5bgvhf6f6a5vzrmwi

Active pixel sensors for autonomous spacecraft applications

Phil M. Salomon, Eric R. Fossum, Christopher C. Clark, Edwin W. Dennison, E. Kane Casani, Mark A. Vander Does
1996 Space Sciencecraft Control and Tracking in the New Millennium  
Finally, the encounter phase begins and the tracker must help point science instruments at targets of interest and then repoint the communication link for data transfer.  ...  During the next phase the tracker must help navigate the spacecraft using references along the way.  ...  We also wish to acknowledge the leadership and support for the APS Project provided by Gabriel Udomkesmalee, Group Supervisor, Tracking Sensors Group.  ... 
doi:10.1117/12.255137 fatcat:ufsikg37vvaztabjgpsnnkz6iq

An accuracy measurement method for star trackers based on direct astronomic observation

Ting Sun, Fei Xing, Xiaochu Wang, Zheng You, Daping Chu
2016 Scientific Reports  
Star tracker is one of the most promising optical attitude measurement devices and it is widely used in spacecraft for its high accuracy.  ...  A new and robust accuracy measurement method for a star tracker based on the direct astronomical observation is proposed here.  ...  It can also verify the functions of star pattern recognition, dynamic performance, star sensitivity, reliability and other technical specifications of a star tracker.  ... 
doi:10.1038/srep22593 pmid:26948412 pmcid:PMC4984851 fatcat:j5kuiyej4jcfhmmnddnjwsplrq

Application of the active-pixel-sensor concept to guidance and navigation

Eric R. Fossum, Randall K. Bartman, Allan R. Eisenman, George E. Sevaston, Richard H. Stanton
1993 Space Guidance, Control, and Tracking  
Charge-coupled devices (CCDs) have been used extensively in the past in star trackers and fine guidance systems. A new technology, the active pixel sensor, is a possible successor to CCDs.  ...  These improvements include random access capability, easy window-of-interest readout, non-destructive readout for signal-to-noise improvement, high radiation tolerance, simplified clocking voltages, and  ...  The authors are grateful to many of their colleagues at JPL and in the image sensor community for enlightening discussions. The authors appreciate the support of V. Sarohia of JPL and W.  ... 
doi:10.1117/12.157088 fatcat:4ylt6bcc7zefnfq7ma2xp2sa6q

VITRUV - Imaging close environments of stars and galaxies with the VLTI at milli-arcsec resolution [article]

Fabien Malbet, Paulo Garcia , Laurent Jocou , Pierre Labeye, Eric Tatulli
2005 arXiv   pre-print
The VITRUV project has the objective to deliver milli-arcsecond spectro-images of the environment of compact sources like young stars, active galaxies and evolved stars to the community.  ...  Since the fringes are stabilized, we used a 100s elementary exposure time. We have not yet fully investigated the dual feed option in simulations (losses due anisoplanetism).  ...  The considered concept allows long exposure acquisition requested for the high spectral resolution mode.  ... 
arXiv:astro-ph/0507233v1 fatcat:tkgwujl3mrcdbhwryfnpki5v4e

Characterization of the AEOS Adaptive Optics System

Lewis C. Roberts, Jr., Christopher R. Neyman
2002 Publications of the Astronomical Society of the Pacific  
This research made use of the Washington Double Star Catalog maintained at the US Naval Observatory and of the SIMBAD database, operated by the CDS, Strasbourg, France  ...  We thank the staff of the Maui Space Surveillance System for their assistance in taking these data. This research was funded by AFRL/DE under contract to Boeing (contract F29601-00-D-0204).  ...  The bandwidths for the tracker loop and the AO loop were adjusted for each star to optimize image quality. The 700-1060 nm filter was used for all observations.  ... 
doi:10.1086/343221 fatcat:y7pkwpo6abhallmrurdkkga33u

Live-cell imaging of PVD dendritic growth cone in post-embryonic C. elegans

Chun-Hao Chen, Chun-Liang Pan
2021 STAR Protocols  
This protocol is suitable for revealing the dynamic molecular and cellular events in dendrite and axon development of C. elegans.  ...  For complete details on the use and execution of this protocol, please refer to Chen et al. (2019).  ...  If the exposure time is higher (>300 ms), increase laser intensity for 5%-10%. Repeat the process to search for optimal conditions for live-cell imaging.  ... 
doi:10.1016/j.xpro.2021.100402 pmid:33778786 pmcid:PMC7985398 fatcat:36k7cvploreudld2dyxhs6jmtu

A Comprehensive Calibration Method for a Star Tracker and Gyroscope Units Integrated System

Wenfeng Tan, Dongkai Dai, Wei Wu, Xingshu Wang, Shiqiao Qin
2018 Sensors  
In this paper, a comprehensive calibration method for the star tracker and GUs integrated system is proposed from a global perspective.  ...  Firstly, the observation model of the predicted star centroid error (PSCE) with respect to the systematic errors including the star tracker intrinsic parameter errors, GUs errors and fixed angle errors  ...  Abbreviations The following abbreviations are used in this manuscript: GUs Gyroscope units PSC Predicted star centroid ESC Extracted star centroid PSCE Predicted star centroid error Sensors 2018, 18  ... 
doi:10.3390/s18093106 pmid:30223523 pmcid:PMC6164436 fatcat:qwgb27eenvfbzln7bgmuug3wyy

RSOnet: An Image-Processing Framework for a Dual-Purpose Star Tracker as an Opportunistic Space Surveillance Sensor

Siddharth Dave, Ryan Clark, Regina S. K. Lee
2022 Sensors  
This research presents RSOnet, an image-processing framework for space domain awareness using star trackers.  ...  Our research demonstrates that star trackers are a feasible source for RSO detections in LEO by demonstrating the performance of RSOnet on real detections from a star-tracker-like imager in space.  ...  Star trackers generally have a wide FOV, small aperture and capture images with a short exposure time to capture light from many bright stars and analyze their motion on the image plane.  ... 
doi:10.3390/s22155688 fatcat:3s4lci7zwjbxbgodeyaxzdo2my
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