Multi-functional star tracker with precision focal plane position control for small cubesat-class satellites

摘要

An optical system for use in an Earth-orbiting satellite includes a plurality of image sensors disposed on a focal plane having a reference axis orthogonal thereto, optics configured to focus incident light onto the image sensors, a piezoelectric actuator coupled to the image sensors and configured to translate the image sensors in at least two axes each orthogonal to the reference axis, and at least one controller operably coupled to the plurality of image sensors and the piezoelectric actuator. The image sensors are configured to generate at least one image frame from light detected by the plurality of image sensors, the image frame including a target star and at least one guide star. The controller is configured to stabilize the position of the target star by adjusting the position of the piezoelectric actuator based on the changes in the position of the guide star.

主权项

1. An optical system for use in an Earth-orbiting satellite, the optical system comprising:
a plurality of image sensors disposed on a focal plane having a reference axis orthogonal thereto, the plurality of image sensors configured to generate at least one image frame from light detected by the plurality of image sensors, the at least one image frame including a target star and at least one guide star; optics configured to focus incident light onto the plurality of image sensors; a piezoelectric actuator coupled to the plurality of image sensors and configured to translate the plurality of image sensors in at least two axes each orthogonal to the reference axis, the piezoelectric actuator having a position with respect to the reference axis; and at least one controller operably coupled to the plurality of image sensors and the piezoelectric actuator and configured to:
determine a position of the target star within the at least one image frame;track changes in a position of the at least one guide star within the at least one image frame;stabilize the position of the target star by adjusting the position of the piezoelectric actuator based on the changes in the position of the at least one guide star;generate a pointing error of the satellite based on the changes in the position of the at least one guide star; andstabilize an attitude of the satellite based at least on the pointing error.