Heading confidence interval estimation
AssigneeInvenSense, Inc.
InventorsYuan Zheng, Shang-Hung Lin, Kerry Keal
Life of this patent
Estimating the term…
Abstract
An inertial measurement system is disclosed. The inertial measurement system has an accelerometer processing unit that generates a calibrated accelerometer data. The inertial measurement system further includes a magnetometer processing unit generates a calibrated magnetometer data, and a gyroscope processing unit generates a calibrated gyroscope data. Using the calibrated accelerometer data, the calibrated magnetometer data, and the calibrated gyroscope data, the inertial measurement system generates a heading angle error indicative of the accuracy of the heading angle error.
Claims29
An inertial measurement system comprising:
- an accelerometer processing unit operable to generate a calibrated accelerometer data;
- a magnetometer processing unit operable to generate a calibrated magnetometer data;
- and
- a gyroscope processing unit operable to generate a calibrated gyroscope data, wherein the inertial measurement system is operable to generate an orientation angle indicative of the accuracy of the orientation angle using the calibrated accelerometer data, the calibrated magnetometer data, and the calibrated gyroscope data.
The inertial measurement system of claim 16, further including an inverse block responsive to the quaternion output and operable to generate the inverse quaternion signal.
An inertial measurement system comprising:
- an accelerometer processing unit operable to generate a calibrated accelerometer data;
- a magnetometer processing unit operable to generate a calibrated magnetometer data;
- a gyroscope processing unit operable to generate a calibrated gyroscope data,
- wherein the inertial measurement system is operable to generate an angle error, the accuracy of which is measured using a confidence interval relating to the calibrated accelerometer data and the calibrated magnetometer data.
A method of estimating heading using an inertial measurement system comprising:
- calibrating an accelerometer data to generate a calibrated accelerometer data with an accelerometer calibration and gravity extraction block;
- calibrating a magnetometer data to generate a calibrated magnetometer data with a magnetometer calibration and anomaly rejection block;
- calibrating a gyroscope data to generate a gyroscope data with a gyroscope calibration block;
- and
- using the calibrated accelerometer data, the calibrated magnetometer data, and the calibrated gyroscope data, generating an angle error, the angle error being a measure indicative of the accuracy of the orientation angle.
A method of generating an angle error comprising:
- determining whether or not a magnetic anomaly is detected;
- if a magnetic anomaly is not detected, calculating an orientation error boundary with tilt and heading compensation from a calibrated accelerometer data, a calibrated magnetometer data, and a calibrated gyroscope data;
- and
- if a magnetic anomaly is detected, calculating an orientation error boundary using gyroscope data.
Dependencies are inferred from the claim text.