US 12,442,637 B2
Method for providing a navigation information, corresponding system and program product
Nicola Matteo Palella, Rivolta d'adda (IT); and Leonardo Colombo, Lecco (IT)
Assigned to STMicroelectronics S.r.l., Agrate Brianza (IT)
Filed by STMicroelectronics S.r.l., Agrate Brianza (IT)
Filed on Dec. 21, 2020, as Appl. No. 17/128,744.
Claims priority of application No. 102019000025399 (IT), filed on Dec. 23, 2019.
Prior Publication US 2021/0190499 A1, Jun. 24, 2021
Int. Cl. G01C 21/16 (2006.01); G01C 5/06 (2006.01); G01C 25/00 (2006.01); G01S 19/47 (2010.01)
CPC G01C 21/165 (2013.01) [G01C 5/06 (2013.01); G01C 25/00 (2013.01); G01S 19/47 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for providing navigation information by a navigation sensing device, the method comprising:
collecting, by an inertial measurement unit of the navigation sensing device, motion data comprising acceleration and angular rates;
collecting, by an absolute positioning source of the navigation sensing device, three-dimensional absolute position data comprising absolute altitude;
collecting, by a barometer sensor, pressure measurement;
processing, by a first data fusion process, the motion data and the three-dimensional absolute position data to obtain two-dimensional position information;
processing, by a second data fusion process, the pressure measurement and the absolute position data to obtain an altitude estimate, the processing, by the second data fusion process, including:
performing a recursive estimation operation to obtain the altitude estimate, including recursively estimating a state vector including state variables representing calibration parameters, the recursive estimation operation comprising at each iteration performing a system update operation including updating a state transition model estimating the altitude estimate using the pressure measurement and a current estimate of the calibration parameters; and
performing a measurement update operation using the absolute altitude, the measurement update operation comprising:
calculating a difference between the altitude estimate and the absolute altitude;
updating the altitude estimate for the system update operation as a function of the difference; and
feeding back to the system update operation the difference to correct the calibration parameters and the altitude estimate in the system update operation; and
providing navigation information by the navigation sensing device based on the measurement update operation,
wherein a state transition matrix of the state transition model is obtained by performing partial differentials of the state vector versus each of the state variables and a system noise matrix as a diagonal matrix having on a diagonal, standard deviation of errors in system update equations of the state transition model.