초록 ▼

A system for automatically mapping the surface of a celestial body is presented. A satellite in a near polar sun-synchronous orbit about the body includes two or three linear sensing photo-detector arrays mounted transversely to the satellite heading. With two arrays, both are oriented at the same a

A system for automatically mapping the surface of a celestial body is presented. A satellite in a near polar sun-synchronous orbit about the body includes two or three linear sensing photo-detector arrays mounted transversely to the satellite heading. With two arrays, both are oriented at the same angle to the geometric vertical, with one aimed forward and the other aft along the apparent track of the satellite. With three arrays, the third array is oriented downward toward the geometric vertical. Two of the arrays are used to sense the body surface with the satellite velocity providing continuous imaging. With rugged terrain, one angled array and the vertical array sense linear strips of the body disposed parallel to the apparent path of the satellite. With relatively flat terrain the angled arrays are used. Data is acquired by sensing the same elemental areas of strips from a first position in space with a first array, and once the satellite has moved to a second position, with the second array. The two satellite positions and an incremental area on the ground define an equipolar plane. The two arrays produce two data flows which, when corrolated, result in data representative of elevational information for each incremental area of each strip. The system allows near real-time mapping since the imaged areas being compared are included in an equipolar plane, making data correlation for topographic information a matter of comparing the two one-dimensional records.

대표청구항 ▼

A method for acquiring panchromatic or multispectral topographic data of a celestial body through the use of a relatively stable platform spaced from said body and movable relative thereto, said platform carrying at least first and second linear array sets of radiometric sensing detectors aligned tr

A method for acquiring panchromatic or multispectral topographic data of a celestial body through the use of a relatively stable platform spaced from said body and movable relative thereto, said platform carrying at least first and second linear array sets of radiometric sensing detectors aligned transversely to the direction of platform motion, said first and second sets being positioned on said platform at different angles from a geometric vertical with respect to the body for respectively sensing radiance from spaced areal elements of said body, comprising the steps of: moving said platform across said body for sensing linear strips constituted by said areal elements of said body in a direction substantially parallel to the motion of said platform, continuously sensing said areal elements by scanning said linear strips with said first array set from a first position on said platform to produce flows of signal elements representative of one-dimensional spatial and radiometric information, continuously sensing the corresponding strips by scanning them with said second array set from a second position on said platform at said different angle aspect in epipolar planes defined by corresponding said first and second positions and said areal elements corresponding thereto, to produce a second series of flows of signal elements representative of one-dimensional spatial and radiometric information, and comparing the signal elements of said first signal flows with the corresponding signal elements of said second signal flows within the same epipolar planes to derive output signals indicative of elevational information for each areal element of each sensed strip.