Jafar Roshanian; Mehdi Hassani; Shabnam Yazdan; Masoud Ebrahimi
Volume 5, Issue 4 , January 2013, , Pages 1-8
Abstract
Star tracker is an attitude determination device which determines the satellite or spacecraft’s attitude using the star position information in inertial and body references. Star information is collected and stored onboard as a “Star or mission catalog”. There are several star catalogs ...
Read More
Star tracker is an attitude determination device which determines the satellite or spacecraft’s attitude using the star position information in inertial and body references. Star information is collected and stored onboard as a “Star or mission catalog”. There are several star catalogs that contain different kinds of information with different accuracy. In this paper the most used star catalogs are introduced and a few star catalog selection features are recommended. These features are weighted according to the star tracker mission type. For the selected star tracker mission, results demonstrate that Hipparcos star catalog is the best choice. Eventually using Hipparcos star catalog, a mission catalog is developed to be used onboard a typical star tracker.
Jafar Roshanian; Shabnam Yazdani; S. Mehdi Hasani; Masoud Ebrahimi Kachouie
Volume 5, Issue 2 , July 2012, , Pages 15-23
Abstract
Star trackers are one of the most accurate attitude determination devices of a spacecraft. Star trackers are able to determine the spacecraft attitude with the use of recognizing the stars within their field of view. One of the major subsystems of star tracker software is the star pattern recognition ...
Read More
Star trackers are one of the most accurate attitude determination devices of a spacecraft. Star trackers are able to determine the spacecraft attitude with the use of recognizing the stars within their field of view. One of the major subsystems of star tracker software is the star pattern recognition algorithm. In this research a novel star pattern recognition algorithm called Non-Dimensional is considered. This algorithm can recognize the stars within its field of view without using the information of camera calibration. In order to fulfill this goal, the algorithm requires a database which contains the star inertial information. Afterwards a fast search method is used to compare the combinations on the image with database. Eventually there has been a tradeoff between database volume and the update frequency for a better performance.
