Design study: Parallel architectures for autonomous star pattern identification and tracking
Abstract
This paper outlines the results of a pilot study into the feasibility of an advanced concept for star camera design to support spacecraft attitude determination. Such a star camera is envisioned to operate autonomously, to obviate the need for other attitude-related sensors in many cases, and to function efficiently without a priori attitude information. These characteristics are particularly desirable for missions such as interplanetary probes. The design alternatives examined in the study assume a relatively wide field of view system consisting of a sensor, such as an integrating charge-coupled device or focal plane array, a pattern recognition system, such as the winner-take-all associative memory (WAM), and intermediate processing needed to link these key components together. The WAM, in particular, has been applied successfully to the problem of text recognition, which is quite similar to star pattern recognition in many respects. This paper will focus on particular design alternatives, an assessment of various metrics used to characterize star patterns, sensor performance requirements and capabilities, a review of the performance of an existing WAM chip, and expected throughput rates for various design alternatives. In conclusion, recommendations are offered for a preliminary system design for the near term and the far term on the basis of these assessments.
- Publication:
-
NASA STI/Recon Technical Report A
- Pub Date:
- 1993
- Bibcode:
- 1993STIA...9581347W
- Keywords:
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- Architecture (Computers);
- Attitude Indicators;
- Parallel Processing (Computers);
- Pattern Recognition;
- Spacecraft Design;
- Spacecraft Instruments;
- Star Trackers;
- Airborne/Spaceborne Computers;
- Charge Coupled Devices;
- Design Analysis;
- Focal Plane Devices;
- Spacecraft Instrumentation