US 11,988,512 B2
Method for estimating the movement of an object moving in a magnetic field
David Vissiere, Paris (FR); and Mathieu Hillion, Vernon (FR)
Assigned to SYSNAV, Vernon (FR)
Appl. No. 16/630,157
Filed by SYSNAV, Vernon (FR)
PCT Filed Jul. 13, 2018, PCT No. PCT/FR2018/051783
§ 371(c)(1), (2) Date Jan. 10, 2020,
PCT Pub. No. WO2019/012239, PCT Pub. Date Jan. 17, 2019.
Claims priority of application No. 1756675 (FR), filed on Jul. 13, 2017.
Prior Publication US 2020/0132464 A1, Apr. 30, 2020
This patent is subject to a terminal disclaimer.
Int. Cl. G01C 21/16 (2006.01); G01C 21/08 (2006.01)
CPC G01C 21/1654 (2020.08) [G01C 21/08 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method comprising the steps of:
(a) acquiring, by a magnetic measurement unit integral with an object moving in an ambient magnetic field, at least one component:
of the magnetic field and/or
of at least one i-th derivative of the magnetic field, with i≥1, at the magnetic measurement unit;
(b) estimating, by a data processing unit, a movement of said object, wherein at least one component of said movement is estimated using at least one component of the equation ∇nB=fn(Ω)·∇nB+gn(∇n+1B)·V, with n+1≥i and n≥1, and n≥1, where ∇nB is an n-th derivative of the magnetic field, Ω the instantaneous angular velocity, V the instantaneous linear velocity, and fn and gn predetermined functions;
(c) adjusting, by a driving unit of the object, at least one of a speed or a direction of movement of the object in response to the estimated movement.