US 10,328,267 B2 · Methods for constructing posture calibration matrices

Abstract

A device can include a multi-dimensional posture sensor that provides an electrical sensor output representative of alignment of first, second, and third non-parallel axes of the device with the gravitational field of the earth, and a processor that includes a calibration circuit and a posture circuit. The calibration circuit measures a first sensor output for the first device axis and a second sensor output for one of a second device axis while the subject is in a first specified posture, measures sensor outputs for the first, second, and third device axes while the subject is in a second specified posture, calculates one or more coordinate transformations, generates transformed sensor outputs using the coordinate transformations, and calibrates the posture sensor by calculating a calibration transformation using the first and second sensor outputs and the transformed sensor outputs. The posture circuit determines a subsequent posture of the subject using the posture sensor.

Claims20

Dependent claims

A medical device deployable by being worn by, or implanted in, a subject, the device comprising:

a multi-dimensional posture sensor configured to provide an electrical sensor output representative of alignment of respective first, second, and third axes of the device with the gravitational field of the earth while the device is deployed;
and
a processor communicatively coupled to the posture sensor and including:
a posture calibration circuit configured to:
measure a first sensor output for the first device axis and a second sensor output for one of the second or third device axes for a first specified posture of the subject;
calculate first transformation components using the first and second sensor outputs;
measure additional sensor outputs for the first, second, and third device axes for a second specified posture of the subject;
calculate second transformation components using the first transformation components and the additional sensor outputs;
and
calculate elements of a calibration matrix using the first and second transformation components;
and
a posture circuit configured to determine a subsequent posture of the subject using outputs of the posture sensor and the calibration matrix.

9 more elements

A method of controlling operation of a medical device deployable by being worn by, or implanted in, a subject, the method comprising:

determining a calibration transformation for a multi-dimensional posture sensor by a two posture process including:
measuring a first sensor output for a first device axis and a second sensor output for one of a second device axis or a third device axis for a first specified posture of the subject;
calculating first transformation components using the first and second sensor outputs;
measuring additional sensor outputs for the first, second and third device axes for a second specified posture;
calculating second transformation components using the first transformation components and the additional sensor outputs;
and
calculating elements of a calibration matrix using the first transformation components and the second transformation components;
and
determining subsequent subject posture using subsequent calibrated posture sensor output and the calibration matrix.

6 more elements

Dependencies are inferred from the claim text.

Methods for constructing posture calibration matrices

Life of this patent

Methods for constructing posture calibration matrices

Life of this patent

Abstract

Claims20