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Quaternion Attitude Estimation Using Vector Observations
This paper contains a critical comparison of estimators minimizing Wahba’s loss function. Some new results are presented for the QUaternion ESTimator (QUEST) and EStimators of the Optimal Quaternion
ESOQ: A Closed-Form Solution to the Wahba Problem
A closed-form solution to the problem of optimal spacecraft attitude estimation based on vectors observation, known as the Wahba problem, is presented. The algorithm first provides the closed-form
Second Estimator of the Optimal Quaternion
ENGINEERING NOTES are short manuscripts describing new developments or important results of a preliminary nature. These Notes cannot exceed 6 manuscript pages and 3 Žgures; a page of text may be
How to Estimate Attitude from Vector Observations
Wahba'soptimality condition has provided the basis for many attitude determination algorithms and is given an overview of the most popular and most promising algorithm and to provide accuracy and speed comparisons.
The Flower Constellations
This paper introduces a methodology to design a set of satellite constellations, called the Flower Constellations, which is generally characterized by repeatable ground tracks and a suitable phasing
Norm-Constrained Kalman Filtering
The problem of estimating the state vector of a dynamical system from vector measurements when it is known that the state vector satisfies norm equality constraints is considered. The case of a
The Pyramid Star Identification Technique
: A new highly robust algorithm, called Pyramid, is presented to identify the stars observed by star trackers in the general lost-in-space case, where no a priori estimate of pointing is available.
A Survey on Star Identification Algorithms
Algorithms used in star identification, commonly used in startrackers to determine the attitude of a spacecraft are surveyed, including algorithms that use a star camera with an imaging array and analgorithm to match observed directions of stars with catalog directions ofStars without requiring reorienting the camera or the spacecraft.
The 3-D lattice theory of Flower Constellations
A new 3D Lattice Flower Constellations (3D-LFCs) framework is found that improved the average positioning accuracy by 3.5 % while reducing launch requirements when compared to the existing Galileo GNSS constellation.
The 2-D lattice theory of Flower Constellations
The 2-D lattice theory of Flower Constellations, generalizing Harmonic Flower Constellations (the symmetric subset of Flower Constellations) as well as the Walker/ Mozhaev constellations, is