Body motion measuring apparatus

• US 7,670,303 B2
• Filed: 11/02/2004
• Issued: 03/02/2010
• Est. Priority Date: 11/04/2003
• Status: Expired due to Fees

• Current Assignee: Tanita Corporation (Tanita)
• Original Assignee: Tanita Corporation (Tanita)
• Inventors: Sato, Tomio, Nishibayashi, Kenji
• Primary Examiner(s): Hindenburg; Max
• Assistant Examiner(s): Lloyd; Emily M
• Application Number:
  US10/978,354
• Publication Number:
  US 20050096569A1
• Time in Patent Office: 1,946 Days
• Field of Search: 600/595, 377/24.2, 702/160
• US Class Current: 600/595
• CPC Class Codes: A61B 5/1038 Measuring plantar pressure during gait
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A63B 2220/40 Acceleration
• CPC Class Codes: A63B 2220/803 Motion sensors
• CPC Class Codes: G01C 22/006 Pedometers

Abstract

A body motion measuring apparatus is described, embodiments of which include an apparatus for detecting the magnitudes of motions in different directions at a time using body motion sensors, calculating the size V of a composite vector based on the relationship between the magnitudes of the motions, comparing the size V of the composite vector with a reference value to determine whether the size V of the composite vector is adequate, calculating an angle θ based on the relationship between the magnitudes of the motions when V is determined to be adequate, calculating a body motion output M taking the angle θ into account, and counting a predetermined body motion based on the relationship between M and a predetermined elapsed time.

Claims

1. A body motion measuring apparatus comprising:

body motion sensors,

composite vector calculation means,

composite vector determination means,

angle calculation means,

body motion output calculation means, and

body motion counting means,

wherein

the body motion sensors detect the magnitudes of motions in different directions at a time,

the composite vector calculation means calculates the size of a composite vector derived based on the relationship between the magnitudes of the motions in the directions detected by the body motion sensors,

the composite vector determination means determines the adequacy of the size of the composite vector calculated by the composite vector calculation means,

the angle calculation means calculates an angle derived based on the relationship between the magnitudes of the motions in the directions detected by the body motion sensors, when the size of the composite vector determined by the composite vector determination means is adequate,

the body motion output calculation means calculates a body motion output derived from the relationship between the magnitudes of the motions in the directions detected by the body motion sensors and the angle by the angle calculation means, and

the body motion counting means times predetermined elapsed time and counts a predetermined body motion based on the relationship between the body motion output calculated by the body motion output calculation means and the predetermined elapsed time.

2. The apparatus of claim 1, wherein

the body motion sensors detect the magnitudes X and Y of motions in X and Y directions perpendicular to each other at a time, the composite vector calculation means calculates the size V of a composite vector by substituting the magnitudes X and Y of the motions in the directions perpendicular to each other into a formula represented by V=√

(X²+Y²),

the composite vector determination means compares the size V of the composite vector calculated by the composite vector calculation means with a reference value to determine whether the size V is not smaller than the reference value,

the angle calculation means calculates an angle θ

by substituting the magnitudes X and Y of the motions in the directions perpendicular to each other detected at a time by the body motion sensors into a formula represented by θ

=tan<sup>−

1</sup>(Y/X), and

the body motion output calculation means calculates a body motion output M by substituting the magnitudes X and Y of the motions in the directions perpendicular to each other detected at a time by the body motion sensors and the angle θ

calculated by the angle calculation means into a formula represented by M=X cos θ

+Y sin θ

.

3. The apparatus of claim 1, wherein

the body motion sensors detect the magnitudes X, Y and Z of motions in X, Y and Z directions perpendicular to one another at a time,

the composite vector calculation means calculates the size V of a composite vector by substituting the magnitudes X, Y and Z of the motions in the directions perpendicular to one another detected at a time by the body motion sensors into a formula represented by V=√

(X²+Y²+Z²),

the composite vector determination means compares the size V of the composite vector calculated by the composite vector calculation means with a reference value to determine whether the size V is not smaller than the reference value,

the angle calculation means calculates an angle θ

_XY by substituting the magnitudes X and Y of the motions in the directions perpendicular to each other detected at a time by the body motion sensors into a formula represented by θ

_XY=tan<sup>−

1</sup>(Y/X),

the body motion output calculation means calculates a body motion output B based on the magnitudes Y and X of the motions in the directions perpendicular to each other, by substituting X and Y out of the magnitudes of the motions in the directions perpendicular to one another detected at a time by the body motion sensors and the angle θ

_XY calculated by the angle calculation means into a formula represented by B=X cos θ

_XY+Y sin θ

_XY,

the angle calculation means also calculates an angle θ

_BZ by substituting Z out of the magnitudes of the motions in the directions perpendicular to one another detected at a time by the body motion sensors and the body motion output B calculated by the body motion output calculation means into a formula represented by θ

_BZ=tan<sup>−

1</sup>(Z/B), and

the body motion output calculation means also calculates a body motion output M based on the magnitudes X, Y and Z of the motions in the directions perpendicular to one another, by substituting the calculated body motion output B, Z out of the magnitudes of the motions in the directions perpendicular to one another detected at a time by the body motion sensors, and the angle θ

_BZ calculated by the angle calculation means into a formula represented by M=B cos θ

_BZ+Z sin θ

_BZ.

4. The apparatus of claim 1, wherein the body motion counting means counts the body motion as the predetermined body motion when the body motion output M calculated by the body motion output calculation means is larger than an upper limit.

5. The apparatus of claim 2, wherein the body motion counting means counts the body motion as the predetermined body motion when the body motion output M calculated by the body motion output calculation means is larger than an upper limit.

6. The apparatus of claim 3, wherein the body motion counting means counts the body motion as the predetermined body motion when the body motion output M calculated by the body motion output calculation means is larger than an upper limit.

7. The apparatus of claim 1, wherein the body motion counting means counts the body motion as the predetermined body motion when the body motion output M calculated by the body motion output calculation means is larger than an upper limit and lower than a lower limit.

8. The apparatus of claim 2, wherein the body motion counting means counts the body motion as the predetermined body motion when the body motion output M calculated by the body motion output calculation means is larger than an upper limit and lower than a lower limit.

9. The apparatus of claim 3, wherein the body motion counting means counts the body motion as the predetermined body motion when the body motion output M calculated by the body motion output calculation means is larger than an upper limit and lower than a lower limit.

10. The apparatus of claim 1, wherein the body motion counting means counts the body motion as the predetermined body motion based on the relationship between the state of change in difference between the upper peak and lower peak of the body motion output M calculated by the body motion output calculation means and the predetermined elapsed time.

11. The apparatus of claim 2, wherein the body motion counting means counts the body motion as the predetermined body motion based on the relationship between the state of change in difference between the upper peak and lower peak of the body motion output M calculated by the body motion output calculation means and the predetermined elapsed time.

12. The apparatus of claim 3, wherein the body motion counting means counts the body motion as the predetermined body motion based on the relationship between the state of change in difference between the upper peak and lower peak of the body motion output M calculated by the body motion output calculation means and the predetermined elapsed time.