公开(公告)号：US12282104B2

公开(公告)日：2025-04-22

申请号：US17702009

申请日：2022-03-23

Applicant: NEC Corporation

Inventor： Chika Umegaki ,  Kenta Senzaki ,  Katsuya Odaka ,  Hironobu Mori ,  Kyoko Murozono

IPC: G01S19/40 ,  G01C21/02 ,  G01C21/24 ,  G01S19/48

Abstract: A satellite attitude estimation system includes an infrared sensor configured to capture an infrared image of a target satellite for which an attitude is to be estimated. The system determines, in the captured infrared image, a first pixel having a largest luminance and a second pixel having a smallest luminance in the infrared image. The system associates the first pixels with first coordinates of a 3D structure of the target satellite, and associates the second pixels with second coordinates of the 3D structure of the target satellite. The system computes a first normal vector to a surface of the 3D structure for the first coordinates, and computes a second normal vector to the surface of the 3D structure for the second coordinates. The system estimates a direction of the target satellite to the sun before the infrared image was taken, using the computed first and second normal vectors.

公开(公告)号：US20220317314A1

公开(公告)日：2022-10-06

申请号：US17702009

申请日：2022-03-23

Applicant: NEC Corporation

Inventor： Chika UMEGAKI ,  Kenta Senzaki ,  Katsuya Odaka ,  Hironobu Mori ,  Kyoko Murozono

IPC: G01S19/40 ,  G01C21/24 ,  G01C21/02 ,  G01S19/48

Abstract: A satellite attitude estimation system 20 includes a determination unit 21 which determines the maximum pixel, which is a pixel with the largest luminance, and the minimum pixel, which is a pixel with the smallest luminance, respectively, in an infrared image, which is an image taken by an infrared sensor of a target satellite that is a satellite whose attitude is to be estimated, an association unit 22 which associates the determined maximum and minimum pixels with coordinates on the 3D structure of the target satellite, respectively, a computation unit 23 which computes normal vectors for a surface including the coordinates associated with the pixel, respectively, over the coordinates associated with each pixel, and a sun direction estimation unit 24 which estimates the direction of the sun relative to the target satellite before the infrared image is taken using the computed normal vectors.