Imu system for assessing head and torso orientation during physical motion

Patent metadata

Field	Value
Publication number	US-2016339293-A1
Application number	US-201515112515-A
Country	US
Kind code	A1
Filing date	Jan 26, 2015
Priority date	Jan 27, 2014
Publication date	Nov 24, 2016
Grant date	—

Abstract

A method and apparatus for monitoring the head and torso orientation of a subject during physical motion. The method and apparatus employ at least two inertial measurement units (IMUs) being temporally synchronized with each other and each measuring three degrees of freedom of angular velocity, acceleration, and optionally magnetic field. A first IMU being affixed to the head of the subject and the second IMU being affixed to the torso of the subject. The orientation of the head, the orientation of the torso, and optionally the relative orientation of the head and torso are calculated based on the data from the IMU's and optionally magnetometer data. The resultant output data is transmitted to a host device (computer, tablet, smart phone) and can be used for monitoring, training, coaching, worker safety and health, and/or rehabilitation.

First claim

What is claimed is:

1 . An apparatus for monitoring the head and torso orientation of a subject during physical motion, said apparatus comprising:
at least two inertial measurement units each measuring three degrees of freedom of angular velocity and three degrees of freedom of acceleration and outputting acceleration data and angular rate gyro data, a first of the at least two inertial measurement units being temporally synchronized with a second of the at least two inertial measurement units such that the acceleration data and angular rate gyro data from the first inertial measurement unit and the second inertial measurement unit are temporally synchronized; a first mounting system supporting the first inertial measurement unit for movement therewith, the first mounting system being connectable to the head of the subject such that the data from the first inertial measurement unit is used to calculate the orientation of the head of the subject; a second mounting system supporting the second inertial measurement unit for movement therewith, the second mounting system being connectable to the torso of the subject such that the data from the second inertial measurement unit is used to calculate the orientation of the torso of the subject; a central processing unit for receiving the acceleration data and the angular rate gyro data from the first and second inertial measurement units, the central processing unit calculating the orientation of the head and the orientation of the torso in response to the acceleration data and the angular rate gyro data from the first and second inertial measurement units and outputting resultant data; and a host device receiving the resultant data and outputting a response to a user indicative of the head and torso orientation of the subject.

2 . The apparatus according to claim 1 wherein the central processing unit calculates the orientation of the head, the orientation of the torso, and the orientation of the head relative to the torso in response to the acceleration data and the angular rate gyro data from the first and second inertial measurement units and outputs the resultant data.

3 . The apparatus according to claim 1 wherein at least one of the at least two inertial measurement units measures a local magnetic field and outputs magnetometer data,
wherein the central processing unit calculates the orientation of the head and the orientation of the torso in response to the acceleration data, the angular rate gyro data, and the magnetometer data.

4 . The apparatus according to claim 3 wherein the central processing unit calculates the orientation of the head, the orientation of the torso, and the orientation of the head relative to the torso in response to the acceleration data, the angular rate gyro data, and the magnetometer data and outputs the resultant data

5 . The apparatus according to claim 1 , further comprising:
a magnetometer measuring a local magnetic field and outputting magnetometer data, the magnetometer being separate from the first and second inertial measurement units, wherein the central processing unit calculates the orientation of the head and the orientation of the torso in response to the acceleration data and the angular rate gyro data from the first and second inertial measurement units and the magnetometer data from the magnetometer.

6 . The apparatus according to claim 5 wherein the central processing unit calculates the orientation of the head, the orientation of the torso, and the orientation of the head relative to the torso in response to the acceleration data and the angular rate gyro data from the first and second inertial measurement units, and the magnetometer data from the magnetometer and outputs the resultant data

7 . The apparatus according to claim 1 , further comprising:
a transmission system operably coupled between the first and second inertial measurement units and the central processing unit, the transmission system transmitting the acceleration data and the angular rate gyro data from the first and second inertial measurement units to the central processing unit.

8 . The apparatus according to claim 7 wherein the transmission system is wireless.

9 . The apparatus according to claim 1 , further comprising:
a transmission system operably coupled between the central processing unit and the host device, the transmission system transmitting at least the resultant data to the host device.

10 . The apparatus according to claim 9 wherein the transmission system is wireless.

11 . The apparatus according to claim 9 wherein the transmission system transmits the acceleration data and the angular rate gyro data from the first and second inertial measurement units and the resultant data to the host device.

12 . The apparatus according to claim 1 wherein the first mounting system includes a helmet worn by the subject, the first inertial measurement unit being fixedly attached to or embedded with the helmet.

13 . The apparatus according to claim 1 wherein the second mounting system includes a body-worn mounting system worn by the subject, the second inertial measurement unit being fixedly attached to or embedded with the body-worn mounting system.

14 . The apparatus according to claim 1 wherein the host device is a computer, tablet, smart phone, or CPU-enabled devices, wherein the output of the host device is delivered in visual, audible, or tactile forms.

15 . A method for monitoring the head and torso orientation of a subject during physical motion, said method comprising:
employing at least two inertial measurement units each measuring three degrees of freedom of angular velocity and three degrees of freedom of acceleration and outputting acceleration data and angular rate gyro data, a first of the at least two inertial measurement units being temporally synchronized with a second of the at least two inertial measurement units such that the acceleration data and angular rate gyro data from the first inertial measurement unit and the second inertial measurement unit are temporally synchronized; affixing the first inertial measurement unit to the head of the subject for movement therewith; affixing the second inertial measurement unit to the torso of the subject for movement therewith; calculating the orientation of the head and the orientation of the torso in response to the acceleration data and the angular rate gyro data from the first and second inertial measurement units and outputting resultant data; and receiving the resultant data by a host device and outputting a response to a user indicative of the head and torso orientation of the subject on the host device.

16 . The method according to claim 15 wherein the calculating the orientation of the head and the orientation of the torso in response to the acceleration data and the angular rate gyro data from the first and second inertial measurement units comprises calculating the orientation of the head, the orientation of the torso, and the orientation of the head relative to the torso in response to the acceleration data and the angular rate gyro data from the first and second inertial measurement units.

17 . The method according to claim 15 , further comprising:
employing a magnetometer measuring a local magnetic field and outputting magnetometer data, and calculating the orientation of the head and the orientation of the torso in response to the acceleration data, the angular rate gyro data, and the magnetometer data.

18 . The method according to claim 17 wherein the magnetomet

Assignees

• Univ Michigan Regents

Inventors

• Perkins Noel C
• Mcginnis Ryan S
• Copple Brian R

Classifications

• A61B5/1124

  Determining motor skills · CPC title

• G06K9/00342

  Physics · mapped topic

• A61B2562/0219

  Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches · CPC title

• G01R33/0206

  Three-component magnetometers · CPC title

• A63B2225/52

  modulated by measured values · CPC title