초록 ▼

An earth sensor assembly for an orbiting spacecraft which includes a two dimensional microbolometer area array detector as the detective source for capturing full or partial infrared (IR) images of the earth. The earth sensor assembly further includes an input optic head assembly for collecting inci

An earth sensor assembly for an orbiting spacecraft which includes a two dimensional microbolometer area array detector as the detective source for capturing full or partial infrared (IR) images of the earth. The earth sensor assembly further includes an input optic head assembly for collecting incident radiant power emitted from the earth and for directing it to a focal plane of the microbolometer area array. The microbolometer detector converts the detected radiant power into electric signals. Also included are sensor electronics and data processing means for processing the converted signals and determining the attitude of the spacecraft relative to the earth. Also disclosed is an algorithm for processing the earth image information generated by the microbolometer area array and for determining the three axis attitude (pitch, roll and yaw) of the spacecraft.

대표청구항 ▼

[ What is claimed is:] [1.] A method of determining the attitude of a spacecraft in an orbit about the earth using an area array sensor on said spacecraft, said method comprising the steps of:collecting infrared radiation emitted from the earth;continuously projecting the collected infrared radiatio

[ What is claimed is:] [1.] A method of determining the attitude of a spacecraft in an orbit about the earth using an area array sensor on said spacecraft, said method comprising the steps of:collecting infrared radiation emitted from the earth;continuously projecting the collected infrared radiation as an image of the earth and its surroundings onto a two dimensional area array focal plane of the array sensor, the image containing information about the entire earth limb at low earth orbit, the area array focal plane comprising a plurality of pixels;detecting pixels of the area array focal plane on which the image is formed;selecting those pixels of the area array focal plane that contain information about an earth limb;converting the selected pixels into a plurality of signals representing earth limb data;calculating the x- and y-coordinates of the earth center of the detected earth image using the earth limb data; anddetermining as output information the attitude of said spacecraft with respect to the earth using the calculated earth center.