Real-time star point centroid location method and device based on FPGA

Abstract

The present invention discloses a real-time star point centroid location method based on FPGA. The method comprises the following steps: calculating threshold of the current scanned and input star image pixels; performing threshold segmentation of M channel data formed by the pixels; outputting the M-channel results through threshold segmentation to an M*M template; performing the determination of the star point centroid of the pixels through adoption the template; determining whether the sum of the pixel gray level of the row where the centre pixel in the template is located is the maximum of the sum of each row of gray level pixels or not, determining whether the sum of the pixel gray level of the column where the centre pixel in the template is located is the maximum of the sum of each column of gray level pixels or not, and determining whether the position where the star point centroid is roughly located is the coordinate position where the centre pixel is located or not; performing centroid calculation of the pixels in the template of the star point; finely locating the coordinate position of the star point centroid; and finally, outputting the centroid features and the coordinate buffer memory. The real-time star point centroid location method based on FPGA fully employs the characteristic of hardware running parallelism to realize direct determination and extraction of star points, and the hardware design adopts pipeline architecture to realize pixel processing in real time, therefore the consumption of storage resources is small, and the centroid location is rapid and accurate.

Description

technical field [0001] The invention belongs to the field of star sensor image processing in the aerospace field, and more specifically relates to an FPGA-based real-time star point centroid positioning method and device. Background technique [0002] The star sensor is the main equipment of the celestial navigation system, and it is a high-precision and high-reliability attitude measurement component. The working principle of the star sensor is that the image sensor captures the star map of the current field of view, obtains the rough positioning of the star point through the preprocessing of the star map, and then extracts the star point through the sub-pixel fine positioning technology and calculates the star point centroid coordinates and grayscale information , and finally use the star point information to obtain the three-axis attitude of the carrier relative to the earth-centered inertial coordinate system by using the star map recognition algorithm. [0003] The pos...

AI Technical Summary

Problems solved by technology

Algorithms for ellipse fitting and Gaussian surface fitting are complex and not easy to implement in hardware

The relatively simple one that is suitable for hardware implementation is the centroid method. Its calculation formula needs division operation. The division operation consumes hardware resources and is slow to calculate. Therefore, how to realize fast and accurate centroid calculation is also the focus of research.

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