Implementation of a real-time star centroid extraction algorithm with high speed and superior denoising ability
Applied Optics
|April 26, 2022
Summary
This study introduces a fast star centroid extraction algorithm for star trackers, improving attitude determination accuracy. The real-time FPGA-based method achieves high precision and stability for attitude measurement.
Area of Science:
- Aerospace Engineering
- Computer Vision
- Astrodynamics
Background:
- Star trackers are crucial for precise attitude determination in spacecraft.
- Star centroid extraction is a computationally intensive process impacting attitude update rates.
- Existing methods struggle with real-time processing demands.
Purpose of the Study:
- To develop a real-time star centroid extraction algorithm for enhanced star tracker performance.
- To improve the attitude update rate and accuracy of spacecraft attitude determination.
- To address the computational bottleneck in star centroid extraction.
Main Methods:
- Implemented a Field-Programmable Gate Array (FPGA)-based algorithm for real-time processing.
- Utilized a 1D top-hat filter for robust star segmentation under varying backgrounds.
- Employed image stitching to reconstruct complete star frames from multichannel data.
- Applied the center-of-mass algorithm for precise star coordinate extraction.
Main Results:
- Achieved a single-frame processing time of approximately 5.2 ms for a 2048x2048 pixel sensor.
- Demonstrated a standard deviation of star centroid error within 10^-2 pixels.
- Attained a standard deviation of attitude error as low as (2.6, 2.2, 12.0) arcseconds.
Conclusions:
- The proposed FPGA-based algorithm enables real-time star centroid extraction.
- The algorithm provides high accuracy and stability for attitude measurement.
- This advancement supports faster and more precise attitude updates for spacecraft.
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