US 12,235,129 B2
Calibration method for a micromachined inertial angle sensor and calibration system
Nicolas Jean-Marc Frédéric Vercier, Valence (FR); and Bernard Chaumet, Chatellerault (FR)
Assigned to THALES, Courbevoie (FR)
Filed by THALES, Courbevoie (FR)
Filed on Dec. 20, 2022, as Appl. No. 18/085,391.
Claims priority of application No. 21 14368 (FR), filed on Dec. 23, 2021.
Prior Publication US 2023/0204387 A1, Jun. 29, 2023
Int. Cl. G01C 25/00 (2006.01)
CPC G01C 25/005 (2013.01) 15 Claims
OG exemplary drawing
 
1. A method of calibrating a micromachined inertial angle sensor comprising a support, at least one vibrating mass movable relative to the support, at least one excitation transducer for exciting a vibrating movement of the vibrating mass, at least one detection transducer for detecting a vibration of the vibrating mass, and at least one electrostatic transducer capable of applying an adjustable electrostatic stiffness to the vibrating mass, the calibration method comprising the steps of:
receiving, by the angle sensor, a predetermined vibrational excitation emitted from an excitation device;
measuring, by the detection transducer, the vibration of the vibrating mass, to obtain a measurement signal based on the measurement by the detection transducer;
converting the measurement signal over a predetermined time window of said measurement signal into a power spectral density;
determining at least one value, called noise value, as a function of a portion of said power spectral density comprising a frequency less than or equal to a predetermined frequency;
adjusting the electrostatic stiffness, by a feedback loop receiving as input the noise value and providing as output a control signal to the electrostatic transducer comprising the electrostatic stiffness to be applied to the vibrating mass that minimises the noise value;
applying, by the electrostatic transducer, the electrostatic stiffness according to the control signal.