WU; YEONG WEI ANDY (Total 13 Patents Found)

The stability of a recursive estimator process (e.g., a Kalman filter is assured for long time periods by periodically resetting an error covariance P(t n ) of the system to a predetermined reset value P r . The recursive process is thus repetitively forced to start from a selected covariance and continue for a time pe...
An apparatus for star catalog equalization to enhance attitude determination includes a star tracker, a star catalog and a controller. The star tracker is used to sense the positions of stars and generate signals corresponding to the positions of the stars as seen in its field of view. The star catalog contains star lo...
A glitch-free data fusion method for combining multiple attitude solutions is disclosed, wherein a star camera is set as the master star camera. After acquiring attitude solutions from the star cameras, a rotation difference is calculated between a master attitude solution acquired from the master star camera and a sla...
A method and apparatus for estimating attitude sensor bias in a satellite system uses attitude sensors and a spacecraft control processor. Attitude sensors provide output signals, which may contain bias. The present invention interprets the signals, determines the bias present in the signals, and generates an output si...
A method, apparatus, article of manufacture, and a memory structure for designing a robust controller. The method comprises the steps of determining a plant model G of the system dynamics; bounding system dynamics unmodeled by the plant model G of the system dynamics by a weighting function W; applying a transform to a...
Control systems and methods are provided which enhance acquisition range, transient response and offset pointing accuracy in beacon-assisted orientation of a spacecraft to a desired spacecraft attitude A dsrd . The methods receive a beacon signal with antennas that are arranged in a fixed angular relationship to thereb...
A method and apparatus for determining star tracker misalignments is disclosed. The method comprises the steps of defining a defining a reference frame for the star tracker assembly according to a boresight of the primary star tracker and a boresight of a second star tracker wherein the boresight of the primary star tr...
A method, apparatus, article of manufacture, and a memory structure for designing a robust controller. The method comprises the steps of determining a plant model G of the system dynamics; bounding system dynamics unmodeled by the plant model G of the system dynamics by a weighting function W; applying a transform to a...
Methods are provided for dynamically processing successively-generated star tracker data frames and associated valid flags to generate processed star tracker signals that have reduced noise and a probability greater than a selected probability P slctd of being valid. These methods maintain accurate spacecraft attitude...