This utility is a module for a Nanosatellite star tracker. A Star Tracker aims to provide the satellite with its attitude in Euclidean space at a low cost, significantly lower than traditional star trackers used on larger satellites. This module determines the possible combinations of star triads given an image file.
OpenCV 3.2
The star extraction is done through blob analysis using OpenCV. Given an image from the satellite's camera feed, we load the image into a buffer, and do some preprocessing on the image to reduce the noise before doing the blob analysis.
- Load image into buffer
- Apply greyscale mask
- Convert into binary matrix
- Determine blobs in the matrix
- Determine all 3 way combinations
The number star triads is determined by the following:
Where r = 3 and n is the total number of stars found. A threshhold is defaulted to 25 stars per frame as this yields 2300 combinations of stars. More than enough to find a match in our dataset.