公开(公告)号：US11015957B2

公开(公告)日：2021-05-25

申请号：US15782959

申请日：2017-10-13

Applicant: Atlantic Inertial Systems Limited

Inventor： Nicholas R. Wilkinson

IPC: G01C25/00 ,  G01C23/00 ,  G01C21/00 ,  G01C21/16

Abstract: A navigation system comprising: an inertial navigation system arranged to output a first position estimate; a terrain based navigation unit arranged to output a second position estimate; a stored gravity map arranged to receive a position and to output gravity information for that position; and an iterative algorithm unit arranged to determine an INS error state in each iteration; wherein in each iteration the iterative algorithm unit is arranged to: receive the first position estimate and the second position estimate; determine a gravity corrected position estimate based on the first position estimate, the INS error state and the gravity information; and update the INS error state for the next iteration based on the INS error state, the gravity corrected position estimate and the second position estimate.

公开(公告)号：US11041724B2

公开(公告)日：2021-06-22

申请号：US15784255

申请日：2017-10-16

Applicant: Atlantic Inertial Systems, Limited

Inventor： Alan Malvern ,  Nicholas R. Wilkinson

IPC: G01C21/00 ,  G01C21/16 ,  G01C21/04

Abstract: A navigation system comprising: an inertial navigation system arranged to output a first position estimate; a terrain based navigation unit arranged to output a second position estimate; a gravity based navigation unit arranged to output a third position estimate; a stored gravity map arranged to receive a position and to output gravity information for that position; and an iterative algorithm unit arranged to determine an INS error state in each iteration; wherein in each iteration the iterative algorithm unit is arranged to: receive the first position estimate, the second position estimate, and the third position estimate; determine a gravity corrected position estimate based on the first position estimate, the INS error state and the gravity information; and update the INS error state for the next iteration based on the INS error state, the gravity corrected position estimate, the second position estimate and the third position estimate.