giant.stellar_opnav.stellar_class

This module provides a subclass of the OpNav class for performing stellar OpNav.

Interface Description

In GIANT, Stellar OpNav refers to the process of identifying stars in an image and then extracting the attitude information from those stars. This module combines these two processes into the single process of Stellar OpNav.

The StellarOpNav class is the main interface for performing stellar OpNav in GIANT, and in general is all the user will need to interact with in order to process the images. It provides direct access to the ImageProcessing, StarID, and stellar_opnav.estimators objects and automatically performs the required data transfer between the objects for you. To begin you simply provide the StellarOpNav constructor a Camera instance, a ImageProcessing instance or the keyword arguments to creation one, a StarID instance or the keyword arguments to creation one, and the attitude estimation object you wish to use to perform the attitude estimation. You can then use the StellarOpNav instance to perform all of the aspects of stellar OpNav with never having to interact with the internal objects again.

For example, we could do something like the following (from the directory containing sample_data as generated by a call to generate_sample_data):

>>> import pickle
>>> from giant.stellar_opnav import StellarOpNav
>>> with open('sample_data/camera.pickle', 'rb') as in_file:
...     camera = pickle.load(in_file)
>>> camera.only_long_on()
>>> my_sid = StellarOpNav(camera)
>>> my_sid.id_stars()  # id the stars for each image
>>> my_sid.sid_summary()  # print out a summary of the star identification success for each image
>>> my_sid.estimate_attitude()  # estimate an updated attitude for each image

In order to identify stars and estimate the image attitude based off of those stars for all of our images.

For a more general description of the steps needed to perform stellar OpNav, refer to the stellar_opnav documentation. For a more in-depth examination of the StellarOpNav class continue through the following class documentation.

Classes

StellarOpNav

This class serves as the main user interface for performing Stellar Optical Navigation.