In-situ bias correction for MEMS accelerometers
First Claim
Patent Images
1. A method of calibrating an accelerometer, the method comprising:
- setting a scale factor of the accelerometer to a first value, wherein setting the scale factor of the accelerometer to the first value comprises modifying one or more parameters of a laser source;
while the scale factor of the accelerometer is set to the first value, obtaining a first acceleration value;
setting the scale factor of the accelerometer to a second value, wherein setting the scale factor of the accelerometer to the second value comprises further modifying the one or more parameters of the laser source;
while the scale factor of the accelerometer is set to the second value, obtaining a second acceleration value;
based on the first acceleration value and the second acceleration value, determining a bias correction value;
obtaining a third acceleration value; and
correcting the third acceleration value based on the bias correction value.
1 Assignment
0 Petitions
Accused Products
Abstract
In some examples, an accelerometer may self-calibrate while in use by setting a scale factor of the accelerometer to a first value; while the scale factor of the accelerometer is set to the first value, obtaining a first acceleration value; setting the scale factor of the accelerometer to a second value; while the scale factor of the accelerometer is set to the second value, obtaining a second acceleration value; based on the first acceleration value and the second acceleration value, determining a bias correction value; obtaining a third acceleration value; and correcting the third acceleration value based on the bias correction value.
-
Citations
19 Claims
-
1. A method of calibrating an accelerometer, the method comprising:
-
setting a scale factor of the accelerometer to a first value, wherein setting the scale factor of the accelerometer to the first value comprises modifying one or more parameters of a laser source; while the scale factor of the accelerometer is set to the first value, obtaining a first acceleration value; setting the scale factor of the accelerometer to a second value, wherein setting the scale factor of the accelerometer to the second value comprises further modifying the one or more parameters of the laser source; while the scale factor of the accelerometer is set to the second value, obtaining a second acceleration value; based on the first acceleration value and the second acceleration value, determining a bias correction value; obtaining a third acceleration value; and correcting the third acceleration value based on the bias correction value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. An accelerometer device comprising:
-
a proof mass; one or more anchor elements connected to the proof mass; a scale factor control module configured to; set a scale factor of the one or more anchor elements of the proof mass to a first value, wherein the scale factor control module is configured to set the scale factor of the one or more anchor elements of the proof mass to the first value by modifying one or more parameters of a laser source; set the scale factor of the one or more anchor elements of the proof mass to a second value, wherein the scale factor control module is further configured to set the scale factor of the one or more anchor elements of the proof mass to the second value by further modifying one or more parameters of the laser source; a sensing module configured to; while the scale factor of the one or more anchor elements of the proof mass is set to the first value, obtain a first acceleration value; while the scale factor of the one or more anchor elements of the proof mass is set to the second value, obtain a second acceleration value; obtain a third acceleration value; a controller configured to; determine a bias correction value based on the first acceleration value and the second acceleration value; and correct the third acceleration value based on the bias correction value. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18)
-
-
19. An accelerometer device comprising:
-
a proof mass; one or more anchor elements connected to the proof mass; a scale factor control module configured to; set a scale factor of the one or more anchor elements of the proof mass to a first value, wherein the scale factor control module is configured to set the scale factor of the one or more anchor elements of the proof mass to the first value by electrostatically stiffening the one or more anchor elements of the accelerometer; set the scale factor of the one or more anchor elements of the proof mass to a second value, wherein the scale factor control module is further configured to set the scale factor of the one or more anchor elements of the proof mass to the second value by electrostatically stiffening the one or more anchor elements of the accelerometer; a sensing module configured to; while the scale factor of the one or more anchor elements of the proof mass is set to the first value, obtain a first acceleration value; while the scale factor of the one or more anchor elements of the proof mass is set to the second value, obtain a second acceleration value; obtain a third acceleration value; a controller configured to; determine a bias correction value based on the first acceleration value and the second acceleration value; and correct the third acceleration value based on the bias correction value.
-
Specification