US 12,282,104 B2
Satellite attitude estimation system and satellite attitude estimation method
Chika Umegaki, Tokyo (JP); Kenta Senzaki, Tokyo (JP); Katsuya Odaka, Tokyo (JP); Hironobu Mori, Tokyo (JP); and Kyoko Murozono, Tokyo (JP)
Assigned to NEC CORPORATION, Tokyo (JP)
Filed by NEC Corporation, Tokyo (JP)
Filed on Mar. 23, 2022, as Appl. No. 17/702,009.
Claims priority of application No. 2021-062514 (JP), filed on Apr. 1, 2021.
Prior Publication US 2022/0317314 A1, Oct. 6, 2022
Int. Cl. G01S 19/40 (2010.01); G01C 21/02 (2006.01); G01C 21/24 (2006.01); G01S 19/48 (2010.01)
CPC G01S 19/40 (2013.01) [G01C 21/025 (2013.01); G01C 21/24 (2013.01); G01S 19/485 (2020.05)] 20 Claims
OG exemplary drawing
 
1. A satellite attitude estimation system comprising:
an infrared sensor configured to capture an infrared image of a target satellite for which an attitude is to be estimated;
a memory storing software instructions; and
one or more processors configured to execute the software instructions to:
determine, in the captured infrared image, a first pixel having a largest luminance and a second pixel having a smallest luminance in the infrared image;
associate the first pixels with first coordinates of a 3D structure of the target satellite;
associate the second pixels with second coordinates of the 3D structure of the target satellite;
compute a first normal vector to a surface of the 3D structure for the first coordinates;
compute a second normal vector to the surface of the 3D structure for the second coordinates; and
estimate a direction of the target satellite to the sun before the infrared image was taken, using the computed first and second normal vectors.