NANOSATELLITE ATTITUDE ESTIMATION FROM VECTOR MEASUREMENTS USING SVD-AIDED UKF ALGORITHM

2017-03-01
Cilden, Demet
Söken, Halil Ersin
Hacızade, Cengiz
The integrated Singular Value Decomposition (SVD) and Unscented Kalman Filter (UKF) method can recursively estimate the attitude and attitude rates of a nanosatellite. At first, Wahba's loss function is minimized using the SVD and the optimal attitude angles are determined on the basis of the magnetometer and Sun sensor measurements. Then, the UKF makes use of the SVD's attitude estimates as measurement results and provides more accurate attitude information as well as the attitude rate estimates. The elements of "Rotation angle error covariance matrix" calculated for the SVD estimations are used in the UKF as the measurement noise covariance values. The algorithm is compared with the SVD and UKF only methods for estimating the attitude from vector measurements. Possible algorithm switching ideas are discussed especially for the eclipse period, when the Sun sensor measurements are not available.
METROLOGY AND MEASUREMENT SYSTEMS

Suggestions

Attitude estimation for nanosatellites ssing Singular value decomposition and unscented kalman filter
Söken, Halil Ersin; Çilden Güler, Demet (null; 2015-07-10)
The singular value decomposition (SVD), one of the single frame attitude estimation methods, is used together with the unscented Kalman filter (UKF) for nanosatellite attitude estimation. The proposed interlaced algorithm estimates the attitude and gyro biases using three attitude sensors onboard, which are magnetometers, sun sensors and gyroscopes. The algorithm uses the SVD method at first to estimate the optimal attitude by minimizing the Wahba's loss function. In the second phase, the UKF takes this inf...
Photoexcitation Dynamics in Films of C-60 and Zn Phthalocyanine with a Layered Nanostructure
Lane, Paul A.; Cunningham, Paul D.; Melinger, Joseph S.; Kushto, Gary P.; Esentürk, Okan; Heilweil, Edwin J. (2012-02-15)
We elucidate photoexcitation dynamics in C-60 and zinc phthalocyanine (ZnPc) from picoseconds to milliseconds by transient absorption and time-resolved terahertz spectroscopy. Autoionization of C-60 is a precursor to photocarrier generation. Decay of the terahertz signal is due to decreasing photocarrier mobility over the first 20 ps and thereafter reflects recombination dynamics. Singlet diffusion rates in C-60 are determined by modeling the rise of ground state bleaching of ZnPc absorption following C-60 ...
Verification of delay insensitivity in bit-level pipelined dual-rail threshold logic adders
Ismailoglu, A. Neslin; Askar, Murat (2008-02-22)
A delay-insensitivity verification method is proposed for bit-level pipelined systolic dual-rail threshold logic adders, which achieve speed-up through early and input-incomplete carry output generation and which employ bit-wise completion at pipeline registers. The proposed method simplifies the verification task significantly, regardless of the operand length of the adder, such that analysis of three adjacent systoles for the eight possible early/late carry output generation scenarios is sufficient for de...
Aerothermodynamic Shape Optimization of Reentry Capsules Using DSMC and POD Methods
Kutkan, Halit; Eyi, Sinan (null; 2018-07-09)
This paper presents a hybrid method based on proper orthogonal decomposition (POD) with a trained radial basis function (RBF) network, on direct simulation monte carlo (DSMC) solutions for aerothermodynamic front surface optimization of Stardust re-entry. Gaussian and multiquadric RBFs are implemented for comparison, and multiquadric functions are chosen due to their insensitivity to diverse shape parameters. Cubic uniform B-spline curves are used ...
Nanoparticle Nucleation Is Termolecular in Metal and Involves Hydrogen: Evidence for a Kinetically Effective Nucleus of Three {Ir3H2x center dot P2W15Nb3O62}(6-) in Ir(0)(n) Nanoparticle Formation From [(1,5-COD)Ir-I center dot P2W15Nb3O62](8-) Plus Dihydrogen
Özkar, Saim (American Chemical Society (ACS), 2017-04-19)
The nucleation process yielding Ir(0)(similar to 300) nanoparticles from (Bu4N)(5)Na-3[(1,5-COD)Ir center dot P2W15Nb3O62] (abbreviated hereafter as (COD)Ir center dot POM8-, where POM9- = the polyoxometalate, P2W15Nb3O629-) under H-2 is investigated to learn the true molecularity, and hence the associated kinetically effective nucleus (KEN), for nanoparticle formation for the first time. Recent work with this prototype transition metal nanoparticle formation system (J. Am. Chem. Soc. 2014, 136, 17601-17615...
Citation Formats
D. Cilden, H. E. Söken, and C. Hacızade, “NANOSATELLITE ATTITUDE ESTIMATION FROM VECTOR MEASUREMENTS USING SVD-AIDED UKF ALGORITHM,” METROLOGY AND MEASUREMENT SYSTEMS, pp. 113–125, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/69753.