Lunar Aimp Photographic Data Processing System

Abstract

A data processing system which transforms photographic scans of the moon into rectified lunar pictures has been developed during the LUNAR AIMP satellite program of the National Aeronautics and Space Administration's Goddard Space Flight Center. Three coplanar narrowbeam optical sensors mounted on the spinning satellite provide the photographic input to the system. The satellite's processor determines what lunar image data to transmit, delta-modulating and interleaving these data with necessary navigational parameters. The ground processor reconstitutes the delta-modulated image data into lunar pictures, arranged so as to give the appearance of being the projection of the lunar surface onto one of 24 projection planes. This conversion is performed by first locating each lunar element corresponding to an item of image data. Next the projection plane is selected, either as input or by the program. The lunar elements are then mathematically projected onto the plane. This projection is formatted onto magnetic tape, from which the output picture is generated. In the paper, particular attention is paid to the information flow in the overall spacecraft/ ground-processor system. Some reisults of simulations of portions of the systems by personnel of NASA, Goddard Space Flight Center, and the Image Processing Department of the Federal Systems Division of International Business Machines Corporation (IBM), and of the processing of moon surface imagery on IBM's Electro-Optical Simulation Facility (EOSF) are provided.