Dynamic self-calibration of an accelerometer system
One embodiment includes a method for dynamic self-calibration of an accelerometer system. The method includes forcing a proof-mass associated with a sensor of the accelerometer system in a first direction to a first predetermined position and obtaining a first measurement associated with the sensor in the first predetermined position via at least one force/detection element of the sensor. The method also includes forcing the proof-mass to a second predetermined position and obtaining a second measurement associated with the sensor in the second predetermined position via the at least one force/detection element of the sensor. The method further includes calibrating the accelerometer system based on the first and second measurements.
1. A method for dynamic self-calibration of an accelerometer system, the method comprising:
forcing a first proof-mass associated with a sensor of the accelerometer system in a first direction from an electrostatic null position to a first predetermined position in response to a first perturbation of the electrical null;
obtaining a first measurement associated with a second proof-mass of the sensor with the first proof-mass in the first predetermined position via at least one first force/detection element of the sensor, the second proof-mass being coupled to the first proof-mass via a set of flexures;
forcing the first proof-mass in a second direction opposite the first direction from the electrostatic null position to a second predetermined position that is symmetrical with respect to the first predetermined position in response to a second perturbation of the electrical null, the first and second perturbations being approximately equal and opposite;
obtaining a second measurement associated with the second proof-mass of the sensor with the first proof-mass in the second predetermined position via at least one second force/detection element of the sensor; and
calibrating the accelerometer system based on the first and second measurements.
2. The method of claim 1 , wherein obtaining the first and second measurements comprises:
measuring a first net force applied to the second proof-mass via the at least one first force/detection element; and
measuring a second net force applied to the second proof-mass via the at least one second force/detection element.
3. The method of claim 1 , wherein obtaining the first and second measurements comprises measuring a first net force applied to the second proof-mass via the at least one first force/detection element and measuring a second net force applied to the second proof-mass via the at least one second force/detection element, the method further comprising:
calculating a difference between the first measurement comprised of a first capacitance and the second measurement comprised of a second capacitance; and
adjusting the electrostatic null position based on the difference between the first capacitance and the second capacitance.
4. The method of claim 3 , wherein adjusting the electrostatic null position comprises adjusting a relative signal between the first at least one force/detection element and the second at least one force/detection element at the electrostatic null position.