NTRS - NASA Technical Reports Server

Back to Results
On-board landmark navigation and attitude reference parallel processor systemAn approach to autonomous navigation and attitude reference for earth observing spacecraft is described along with the landmark identification technique based on a sequential similarity detection algorithm (SSDA). Laboratory experiments undertaken to determine if better than one pixel accuracy in registration can be achieved consistent with onboard processor timing and capacity constraints are included. The SSDA is implemented using a multi-microprocessor system including synchronization logic and chip library. The data is processed in parallel stages, effectively reducing the time to match the small known image within a larger image as seen by the onboard image system. Shared memory is incorporated in the system to help communicate intermediate results among microprocessors. The functions include finding mean values and summation of absolute differences over the image search area. The hardware is a low power, compact unit suitable to onboard application with the flexibility to provide for different parameters depending upon the environment.
Document ID
Document Type
Conference Paper
Gilbert, L. E. (Martin Marietta Aerospace Denver, CO, United States)
Mahajan, D. T. (Martin Marietta Aerospace Denver, CO, United States)
Date Acquired
August 10, 2013
Publication Date
May 1, 1978
Publication Information
Publication: NASA. Goddard Space Flight Center Flight Mechanics(Estimation Theory Symp.
Subject Category
Distribution Limits
Work of the US Gov. Public Use Permitted.

Related Records

IDRelationTitle19790005950Analytic PrimaryFlight Mechanics/Estimation Theory Symposium
Document Inquiry