Automated Star Sensor Performance Assessment using Real-Sky Data of MEFIST II

ADTE Image Recognition Screen
ADTE Image Recognition Screen

This project regards the testing of a novel tool for batch processing of star sensor imagery, camera performance, and design assessment.

Star sensors based on pattern recognition provide the most accurate attitude solution available for spacecraft, even when using large field of view cameras. Due to advances in CCD, CMOS, integrated circuit technologies, and robust algorithms, star sensors are becoming more and more a viable alternative to solutions that were traditionally cheaper. A great many star sensor hardware is thus currently under development worldwide. This trend creates a market for generic design support software, automated batch processing of imagery resulting from real-sky tests and automated camera performance assessment. For this purpose, the Attitude Determination Test Environment (ADTE) tool was developed (formerly known as SSATT).

The major novelty of the ADTE is that it contains a generic interface to batch process real-sky test imagery that provides as output the average directional accuracy of the camera, lens deviation correction estimates and performance distributions as a function of star magnitude or star class. No sophisticated test set-up or idealized mathematical performance analysis is necessary. The tool includes camera simulation settings and up-to-date detection/rejection, centroiding and pattern recognition algorithms including upgraded versions of Liebe, Quine and Delta-Utec Douma Extension (DUDE). Pattern data storage and retrieval is based on the very fast multidimensional pointer-based array algorithms. Various recursive validation techniques maximize the number of recognized stars per image.

The ADTE tool was first used for the real-sky test of the MEFIST-II camera in the Negev desert. This paper shortly explains the functionality of the tool and algorithms behind it and focuses on the analyses and results performed for MEFIST-II.

Installation of MEFIST on Wise Observatory, Negev desert.