Capturing body movement related to a fixed coordinate system
Briefly, in accordance with one or more embodiments, a kinematic sensor may be carried by or on one or more body segments of a user to obtain one or more kinematic variables based at least in part on movement of the user with respect to a fixed, global reference system. The kinematic sensor comprises a tri-axial accelerometer sensor, a gyroscope sensor, and a magnetometer sensor to define the global reference system and to obtain kinematic data. The kinematic data may be transmitted via a wireless link to a remote information handling system or device, for example to monitor a health status of the user based at least in part on movement of the user with respect to the fixed, global reference system.
1. A method comprising:
defining a global reference system in which movement of a user may be determined;
defining an origin of the global reference system based on a location of an origin of a coordinate axis of a user sensor coupled to a user; and
determining one or more kinematic variables based at least in part on movement of the user sensor with respect to the origin of the global reference system.
2. The method of claim 1 , wherein the defining the origin of the global reference system is further based on an orientation of the user sensor coupled to the user.
3. The method of claim 2 , further comprising determining a health status of the user based on the one or more kinematic variables.
4. The method of claim 1 , wherein the defining the global reference system comprises determining a Y-axis as a unit vector in a direction opposite to gravity, determining an X-axis as a cross product of the Y-axis and a magnetic field vector, or a combination thereof.
5. The method of claim 4 , wherein the defining the global reference system further comprises determining a rotation about the X-axis, the Y-axis, or the Z-axis from a gravity vector and a magnetic field vector.
6. The method of claim 1 , further comprising receiving data on the one or more kinematic variables from the user sensor.
7. The method of claim 1 , further comprising measuring one or more of walking speed, cadence, stride length, step length, step time, variation in step width, stride time, stance time, swing time, double support time, sway variability during stationary stance, or a combination thereof, based at least in part on the one or more kinematic variables.
8. The method of claim 1 , further comprising determining one or more of acceleration, velocity, or displacement, or combinations thereof, based at least in part on the one or more kinematic variables.
9. The method of claim 1 , further comprising mapping a layout of a building to the coordinate system to determine a location of the user within the building based at least in part on the one or more kinematic variables.
10. A non-transitory computer readable medium having one or more instructions that, when executed by one or more processors, cause the one or more processors to:
define a global reference system in which movement of a user may be determined;
define an origin of the global reference system based on a location of an origin of a coordinate axis of a user sensor coupled to a user; and
determine one or more kinematic variables based at least in part on movement of the user sensor with respect to the origin of the global reference system.
11. The non-transitory computer readable medium of claim 10 , wherein the one or more instructions causes the one or more processors to define the origin of the global reference system based on an orientation of the user sensor coupled to the user.
12. The non-transitory computer readable medium of claim 11 , wherein the one or more instructions further cause the one or more processors to determine a health status of the user based on the one or more kinematic variables.
13. The non-transitory computer readable medium of claim 10 , wherein the one or more instructions further cause the one or more processors to define the global reference system by determining a Y-axis as a unit vector in a direction opposite to gravity, determining an X-axis as a cross product of the Y-axis and a magnetic field vector, or a combination thereof.
14. The non-transitory computer readable medium of claim 13 , wherein the one or more instructions further cause the one or more processors to define the global reference system by determining a rotation about the X-axis, the Y-axis, or the Z-axis from a gravity vector and a magnetic field vector.
15. The non-transitory computer readable medium of claim 10 , wherein the one or more instructions further cause the one or more processors to receive data on the one or more kinematic variables from the user sensor.
16. The non-transitory computer readable medium of claim 10 , wherein the one or more instructions further cause the one or more processors to measure one or more of walking speed, cadence, stride length, step length, step time, variation in step width, stride time, stance time, swing time, double support time, sway variability during stationary stance, or a combination thereof, based at least in part on the one or more kinematic variables.
17. The non-transitory computer readable medium of claim 10 , wherein the one or more instructions further cause the one or more instructions to determine one or more of acceleration, velocity, or displacement, or combinations thereof, based at least in part on the one or more kinematic variables.
18. The non-transitory computer readable medium of claim 10 , wherein the one or more instructions further cause the one or more processors to map a layout of a building to the coordinate system to determine a location of the user within the building based at least in part on the one or more kinematic variables.