DETECTION STRATEGIES FOR HIGHRATE, LOW SNR STAR DETECTIONS

We present an assessment of various image thresholding and centroiding algorithms to improve star tracker centroiding accuracy at moderate slew rates (< 10 degrees / s). This work presents an image processing algorithm for star images that preserves star tracker detection accuracy and is able to detect dim stars up to slew rates less than 10 / s. Most star detection algorithms in literature are designed to work in stationary imaging conditions. In this study we explore the algorithmic tradespace for detecting dim elongated stars. The primary factors we consider are: the detection strategy and the sensitivity to exposure time. The performance of the algorithms are assessed using simulations and lab testing. The primary performance metrics are false positive ratio, and false negative ratio of star pixels. We introduced a new algorithm for star detection in moderate slew rates that increases the star detection accuracy in moderate slew rates and it is robust to stray light.