Activity monitoring system insensitive to accelerations induced by external motion factors
First Claim
1. An activity monitoring system adapted to eliminate passive movement components caused by external forces from readout data produced by at least a first and a second motion sensor when attached to a subject during movement, the readout data including gravitational components, movement components caused by active movement of the subject or subject parts, and the passive movement components, the system comprising:
- a processor adapted to;
estimate first and second gravitational components produced by the at least a first and a second motion sensors,determine a rotation matrix based on the first and second estimated gravitational components, the rotation matrix denoting rotation required for the first motion sensor to get aligned with the second motion sensor in orientation,multiply the readout data produced by the first motion sensor with the rotation matrix when rotating the first motion sensor towards the second motion sensor to produce a multiplied result, andsubtract the multiplied result from the readout data produced by the second motion sensor when rotating the first motion sensor towards the second motion sensor.
1 Assignment
0 Petitions
Accused Products
Abstract
This invention relates to an activity monitoring system adapted to eliminate passive movement components caused by external forces from readout data produced by a first and a second motion sensor when attached to a subject during movement. The readout data include gravitational components, movement components caused by active movement of the subject or subject parts, and the passive movement components. A processor estimates first and second gravitational components produced by the at least first and a second motion sensors. It determines a rotation matrix based on the estimated gravitational components, the rotation matrix denoting rotation required for the first sensor to get aligned with the second sensor in orientation. It then multiplies the readout data produced by the first motion sensor with the rotation matrix when rotating the first sensor towards the second sensor. Finally, it subtracts the result of the multiplying from the readout data produced by the second motion sensor when rotating the first motion sensor towards the second motion sensor.
-
Citations
12 Claims
-
1. An activity monitoring system adapted to eliminate passive movement components caused by external forces from readout data produced by at least a first and a second motion sensor when attached to a subject during movement, the readout data including gravitational components, movement components caused by active movement of the subject or subject parts, and the passive movement components, the system comprising:
a processor adapted to; estimate first and second gravitational components produced by the at least a first and a second motion sensors, determine a rotation matrix based on the first and second estimated gravitational components, the rotation matrix denoting rotation required for the first motion sensor to get aligned with the second motion sensor in orientation, multiply the readout data produced by the first motion sensor with the rotation matrix when rotating the first motion sensor towards the second motion sensor to produce a multiplied result, and subtract the multiplied result from the readout data produced by the second motion sensor when rotating the first motion sensor towards the second motion sensor. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
10. An activity monitoring kit comprising:
-
a processor, and at least a first and a second motion sensors adapted to be coupled to the processor, the processor being adapted to eliminate passive movement components caused by external forces from readout data produced by the at least a first and a second motion sensors when attached to a subject during movement, the readout data including gravitational components, movement components caused by active movement of the subject or subject parts, and the passive movement components, wherein eliminating of the passive movement components via the processor comprises; estimating first and second gravitational components produced by the at least a first and a second motion sensors, determining a rotation matrix based on the first and second estimated gravitational components, the rotation matrix denoting rotation required for the first motion sensor to get aligned with the second motion sensor in orientation, multiplying the readout data produced by the first motion sensor with the rotation matrix when rotating a first motion sensor towards a second motion sensor, and subtracting a result of the multiplying from the readout data produced by the second motion sensor when rotating the first motion sensor towards the second motion sensor.
-
-
11. A method of eliminating passive movement components caused by external forces from readout data produced by at least a first and a second motion sensor when attached to a subject during movement, the readout data including gravitational components, movement components caused by active movement of the subject or subject parts, and the passive movement components, the method comprising:
-
estimating first and second gravitational components produced by the at least a first and a second motion sensors; determining a rotation matrix based on the estimated gravitational components, the rotation matrix denoting rotation required for the first motion sensor to get aligned with the second motion sensor in orientation; multiplying the readout data produced by the first motion sensor with the rotation matrix when rotating a first motion sensor towards a second motion sensor; and subtracting a result of the multiplying from the readout data produced by the second motion sensor when rotating the first motion sensor towards the second motion sensor. - View Dependent Claims (12)
-
Specification