372 Hits in 6.3 sec

Onboard spin axis controller for a geostationary spin-stabilized satellite

1987 Journal of Guidance Control and Dynamics  
The effect of uncertainty in the estimator feedforward secular solar torque parameter A, on SAC performance is il- J.  ...  on nominal sensor alignment =commandable bias for transient free sensor switching =commandable parameters to compensate for poten- tial sensor cyclic bias = orbital angle at iteration period N = Earth  ... 
doi:10.2514/3.20215 fatcat:xjvaiqv7nnc4jlyp6xdww2tnja

Attitude Estimation for Sounding Rockets Using Microelectromechanical System Gyros

Jan Kenneth Bekkeng, Mark Psiaki
2008 Journal of Guidance Control and Dynamics  
A direct approach avoids the need to do a complicated geometric reconstruction of the body-axis sun vector based on magnetometer data and on the scalar output of the one-axis sun sensor.  ...  The sun sensor bias estimate seems to diverge before the increased nutation at the end of the flight.  ... 
doi:10.2514/1.32395 fatcat:5gioyzbmyjgkrheek5h7e7zewq

Evaluation of the ESRO IV satellite Horizon Crossing Indicator performance

1975 Journal of Spacecraft and Rockets  
If the satellite is in sunlight, a sun reference pulse is generated when the sun enters the field of view of the com- mand reticle of the sun sensor.  ...  Examples of these are satellite principal spin axis tilt, satellite position vector, spin rate, sun reference pulse, and satellite nutation. J. SPACECRAFT VI.  ... 
doi:10.2514/3.27832 fatcat:i72csl5wobah5fkit5zulmn6ky

Attitude Control of a Bias Momentum Geostationary Satellite in an Inclined Orbit

Hyochoong Bang, Bang Yeop Kim, Han Hwangbo
2000 Journal of Guidance Control and Dynamics  
In this study, the yaw angle is estimated continuously based on the real-time telemetry data at the transmission rate of every 2 s.  ...  Thus, inclination angle is one of the key parameters in the mission operation of geostationary satellites As long as the communication service is not affected, the accept- able tolerance of nonzero inclination  ... 
doi:10.2514/2.4622 fatcat:cyzpx6pw7ffrfcg65yoheblb74

Exploration of energization and radiation in geospace (ERG): challenges, development, and operation of satellite systems

Yosuke Nakamura, Seisuke Fukuda, Yasuko Shibano, Hiroyuki Ogawa, Shin-ichiro Sakai, Shigehito Shimizu, Ersin Soken, Yu Miyazawa, Hiroyuki Toyota, Akio Kukita, Yusuke Maru, Junichi Nakatsuka (+10 others)
2018 Earth, Planets and Space  
The exploration of energization and radiation in geospace (ERG) satellite, nicknamed "Arase, " is the second satellite in a series of small scientific satellites created by the Institute of Space and Astronautical  ...  It was launched on December 20, 2016, by the Epsilon launch vehicle.  ...  Acknowledgements The ERG team acknowledges the effort of Dr. Y. Miyoshi and ERG science center at Nagoya University and all member of the ERG science team.  ... 
doi:10.1186/s40623-018-0863-z fatcat:5sjezwhfyjad3pcycn5lrjui7m

An Attitude Control System for ZA-AeroSat subject to significant Aerodynamic Disturbances

Willem H. Steyn, Mike-Alec Kearney
2014 IFAC Proceedings Volumes  
The satellite will form part of the QB50 constellation to gather science data in the upper layers of the troposphere in the altitude range from 350 km down to 200 km.  ...  All the satellites in the QB50 constellation will carry science payloads to be pointed to within ±10⁰ from the velocity vector direction.  ...  The sensor is based on a low power CMOS camera module of 640 by 480 pixels with a 190º field of view (FOV) fisheye lens.  ... 
doi:10.3182/20140824-6-za-1003.00128 fatcat:oqlvvcqjtzawtlm2maqs7q3kvm

Wavefront Coherent Compensation Technology under Direct Sunlight in Free Space Optical Communication System

Xu Yan, Cao Changqing, Wenrui Zhang, Xiaodong Zeng, Zhejun Feng, Zengyan Wu, Ting Wang
2021 IEEE Photonics Journal  
The charge-coupled device-based Shaker-Hartmann wavefront sensor has been widely used to compensate for wavefront distortion in coherent optical communication.  ...  This study proposes a wavefront recovery method by combining a detector array with an optical nutation of the local oscillator.  ...  Wavefront compensation technology includes detection systems that are not based on wavefront sensors.  ... 
doi:10.1109/jphot.2021.3112489 fatcat:75r2mnw4jfb6hesjtvdmd3ih7m

Scan-by-Nutation: A Spacecraft Control and Scan Motion Concept

R. Weiss, R. L. Bernstein, A. J. Besoms
1975 Journal of Spacecraft and Rockets  
However, the extensive literature on nutation damping may be used to aid in parameter selection and design to enable the maintenance of nutation motion.  ...  Selection of the wheel angular momentum is based on the required scan period, T sec: h= (22/T) (/,1,)”.  ... 
doi:10.2514/3.57036 fatcat:zjz4ar3xmrglnfwmgoy3hr3zjy

A Pre-Processed Orbital Parameters Approach for Improving Cubesat Orbit Propagator and Attitude Determination

Shu Ting GOH, Jiun Wei CHIA, Shi Tong CHIN, Kay Soon LOW, Lip San LIM
2016 Transactions of the Japan Society for Aeronautical and Space Sciences  
The results show a reduction in propagation error on the order of one to two magnitudes.  ...  Both of the satellites carry a low-power consumption in-house-developed attitude determination and control subsystem (ADCS). The ADCS uses an 8-bit microcontroller.  ...  Here, it is assumed that sun sensor and magnetometer readings are available, and the quaternion estimation algorithm (or QUEST 10) ) is used to determine the orientation of the satellite.  ... 
doi:10.2322/tjsass.59.278 fatcat:7y2nfjxurndfbeqhrndfmwtnbu

Attitude Determination for Small Satellites with Infrared Earth Horizon Sensors

Tam Nguyen, Kerri Cahoy, Anne Marinan
2018 Journal of Spacecraft and Rockets  
Infrared Earth horizon sensors (EHS) are capable of providing attitude knowledge for satellites in low-Earth orbit, even during periods of eclipse.  ...  The sensitivity of the estimation accuracy relative to mounting uncertainty was also analyzed, yielding an additional error of 0.7 o on nadir vector estimation for every 0.25 o of boresight offset.  ...  ACKNOWLEDGEMENTS The author would like to thank Professor Kerri Cahoy for her guidance throughout the project, fellow graduate students Meghan Prinkey, Anne Marinan, and the rest of the MIT MicroMAS team  ... 
doi:10.2514/1.a34010 fatcat:6gtrwxzvfvbdxpxasll33vd2dm

Celestial Referenced Attitude Determination of Galileo Spacecraft

Edward C. Wong, John Y. Lai
1982 Journal of Guidance Control and Dynamics  
However, an a priori spin rate estimate from a different sensor, e.g., sun sensor or gyro, is still required for initialization. Ill.  ...  A coarse spin rate estimate provided by the acquisition sun sensor is available for star vectors computation.  ... 
doi:10.2514/3.56171 fatcat:isx4duqzy5e3dkz4nlxoezy2la

ALEXIS Spacecraft Attitude Reconstruction with Thermal/Flexible Motions Due to Launch Damage

Mark L. Psiaki, James Theiler, Jeffrey Bloch, Sean Ryan, Robert W. Dill, Richard E. Warner
1997 Journal of Guidance Control and Dynamics  
One method of estimating the five inde- pendent inertia parameters was based on using the basic ALEXIS filter/smoother to reconstruct the spin vector time history for an orbit-day data set.  ...  Second, it improves the fil- ter/smoother’s model by using off-line batch estimates of on-orbit parameters.  ... 
doi:10.2514/2.4151 fatcat:rd2il2mcqng5xd65rc7uth2w5q

Attitude Stabilization of Synchronous Communications Satellites Employing Narrow-Beam Antennas

1971 Journal of Spacecraft and Rockets  
/woh (7) Equation (7) is used to size the momentum wheel based on an estimate of yaw torque and allowable yaw offset.  ...  Equation (17) is used to estimate reaction wheel size based on a knowledge of disturbance torque magnitudes and fre- quency of momentum desaturation.  ... 
doi:10.2514/3.59732 fatcat:2i4agsdezfecxhr7khcrrn6smm

Analysis of Parameter Correlations of the ECOM Solar Radiation Pressure Model for GPS Orbit

Tae-Suk Bae, Chang-Ki Hong
2019 Journal of Sensors  
Based on the residual analysis, the ECOM is the most appropriate for the Block IIR/IIR-M satellites but does not properly account for the behavior of either older Block IIA or newer IIF satellites.  ...  A total of 500 weeks of GPS daily solutions were estimated with the empirical CODE orbit model (ECOM) to cover various block types of satellites.  ...  However, the final model was rather empirically chosen from various combinations of SRP parameters based on a limited amount of data in the 1990's [4, 16] .  ... 
doi:10.1155/2019/5190496 fatcat:vwwx2v2nkzf6pc4lpnryshmyki

On-orbit Demonstration of a Sun Sensor on the Micro-Satellite MAIDO-1

2011 International Islamic University Malaysia Engineering Journal  
A string-type sun sensor (Fudai Sun Sensor; FSS) was also developed by the students with the technical assistance of JAXA and Advanced Engineering Services (AES) Co. Ltd.  ...  This paper reports the development of MAIDO-1 and FSS as well as the satellite operation by the students and the results of on-orbit experiments.  ...  Spin axis estimation is achieved by using solar and magnetic sensors; spin axis control is based on offline computing.  ... 
doi:10.31436/iiumej.v12i3.142 fatcat:aubdkhxqvvdm3d33a7rspj52ba
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