Electronic apparatus and program

• US 20110238364A1
• Filed: 03/25/2011
• Published: 09/29/2011
• Est. Priority Date: 03/25/2010
• Status: Abandoned Application

• Current Assignee: Seiko Instruments Incorporated (Seiko Group)
• Original Assignee: Seiko Instruments Incorporated (Seiko Group)
• Inventors: Sakai, Satoshi, Tsubata, Keisuke, Nakamura, Hisao, Sugai, Yoshinori, Takakura, Akira, Kato, Kazuo, Ihashi, Tomohiro, Noguchi, Eriko
• Application Number:
  US13/065,668
• Publication Number:
  US 20110238364A1
• Time in Patent Office: Days
• US Class Current: 702/141
• CPC Class Codes: G01C 22/006 Pedometers

Abstract

A calculation unit calculates a magnitude of acceleration in at least one of three separate directions and calculates a synthesized value indicating the magnitudes of the accelerations in the three directions based on the calculated magnitude of the acceleration and the acceleration in the direction separate from at least one of the directions.

Claims

1. An electronic apparatus comprising:

a calculation unit calculating a magnitude of an acceleration in at least one of three separate directions and calculating a synthesized value indicating the magnitudes of the accelerations in the three directions based on the calculated magnitude of the acceleration and the acceleration in the direction separate from at least one of the directions.

2. An electronic apparatus according to claim 1, further comprising:

a first acceleration sensor detecting the acceleration in a first direction and outputting a first signal corresponding to this acceleration;

a second acceleration sensor detecting the acceleration in a second direction perpendicular to the first direction and outputting a second signal corresponding to this acceleration; and

a third acceleration sensor detecting the acceleration in a third direction perpendicular to a plane uniquely specified by the first and second directions and outputting a third signal corresponding to this acceleration,

wherein the calculation unit includes

a plane acceleration calculation unit calculating a value indicating the magnitude of the acceleration on the plane uniquely specified by the first and second directions based on the first and second signals, and

a synthesized value computation unit calculating the synthesized value based on the value indicating the magnitude of the acceleration on the plane and the third signal.

3. An electronic apparatus according to claim 2, further comprising:

a display unit displaying information on a display surface,

wherein the plane uniquely specified by the first and second directions is parallel to the display surface of the display unit.

4. An electronic apparatus according to claim 1, wherein the calculation unit calculates the synthesized value so that a ratio of a signal to noise is higher compared to the synthesized value indicating the magnitudes of the accelerations in the three directions.

5. An electronic apparatus according to claim 4, further comprising:

an acceleration sensor detecting accelerations in three-axis directions perpendicular to each other and outputting acceleration signals X, Y, and Z corresponding to the accelerations in the axis directions, respectively,

wherein the calculation unit calculates the synthesized value S using the acceleration signals X, Y, and Z by an expression

S=(|XY|+|YZ|+|ZX|)/(|X|+|Y|+|Z|).

6. An electronic apparatus according to claim 5, wherein the calculation unit includes

an absolute value data calculation unit calculating absolute values of the acceleration signals X, Y, and Z and absolute values of products XY, YZ, and ZX between the acceleration signals X, Y, and Z and storing the absolute values as absolute value data in an absolute data storage unit,

an addition data calculation unit calculating a product sum (|XY|+|YZ|+|ZX|) and a sum (|X|+|Y|+|Z|) of the absolute value data stored in the absolute value data storage unit and storing the product sum and the sum in an addition data storage unit, and

a division data calculation unit calculating the synthesized value S by dividing the product sum (|XY|+|YZ|+|ZX|) stored in the addition data storage unit by the sum (|X|+|Y|+|Z|).

7. An electronic apparatus according to claim 4, further comprising:

an acceleration sensor detecting accelerations in three-axis directions perpendicular to each other and outputting acceleration signals X, Y, and Z corresponding to the accelerations in the axis directions, respectively,

wherein the calculation unit calculates the synthesized value S using the acceleration signals X, Y, and Z by an expression

S=(|X|ⁿ+|Y|ⁿ+|Z|ⁿ), where n is an integer equal to or larger than 3.

8. An electronic apparatus according to claim 7, wherein the calculation unit includes

an absolute value data calculation unit calculating absolute values of the acceleration signals X, Y, and Z and storing the absolute values as absolute value data in an absolute value data storage unit,

an n-th power value data calculation unit calculating n-th power values of the respective absolute value data stored in the absolute value data storage unit and storing the n-th power values as n-th power value data in an n-th power value data storage unit, and

an addition data calculation unit calculating the synthesized value S by adding the respective n-th power value data stored in the n-th power value storage unit.

9. An electronic apparatus according to claim 7, wherein a plurality of the integers n equal to or larger than is prepared and the calculation unit calculates the synthesized value S by changing the integer n according to a level or a period of the synthesized value S.

10. An electronic apparatus according to claim 8, wherein a plurality of the integers n equal to or larger than is prepared and the calculation unit calculates the synthesized value S by changing the integer n according to a level or a period of the synthesized value S.

11. An electronic apparatus according to claim 4, further comprising:

an acceleration sensor detecting accelerations in three-axis directions perpendicular to each other and outputting acceleration signals X, Y, and Z corresponding to the accelerations in the axis directions, respectively,

wherein the calculation unit calculates the synthesized value S using the acceleration signals X, Y, and Z by an expression

S=(|X|ⁿ+|Y|ⁿ+|Z|ⁿ)^1/m, where n and m are the same integer or different integers equal to or larger than 3.

12. An electronic apparatus according to claim 11, wherein the calculation unit includes

an absolute value data calculation unit calculating absolute values of the acceleration signals X, Y, and Z and storing the absolute values as absolute value data in an absolute value data storage unit,

an n-th power value data calculation unit calculating n-th power values of the respective absolute value data stored in the absolute value data storage unit and storing the n-th power values as n-th power value data in an n-th power value data storage unit,

an addition data calculation unit calculating an addition value obtained by adding the respective n-th power value data stored in the n-th power value storage unit and storing the addition value as addition data in an addition data storage unit, and

an m-power root data calculation unit calculating the synthesized value S by calculating an m-th power root of the addition data stored in the addition data storage unit.

13. An electronic apparatus according to claim 11, wherein a plurality of the integers m and a plurality of the integers n equal to or larger than 3 are prepared and the calculation unit calculates the synthesized value S by changing the integers m and n according to a level or a period of the synthesized value S.

14. An electronic apparatus according to claim 12, wherein a plurality of the integers m and a plurality of the integers n equal to or larger than 3 are prepared and the calculation unit calculates the synthesized value S by changing the integers m and n according to a level or a period of the synthesized value S.

15. An electronic apparatus according to claim 1, further comprising:

a step number detection unit detecting the number of steps based on the synthesized value.

16. An electronic apparatus according to claim 15, further comprising:

a threshold value calculation unit calculating a moving average value of the synthesized values,

wherein the step number detection unit detects the number of steps based on the synthesized values and the moving average value.

17. An electronic apparatus according to claim 15, wherein the electronic apparatus includes a pedometer.

18. An electronic apparatus according to claim 16, wherein the electronic apparatus includes a pedometer.

19. An electronic apparatus according to claim 1, wherein the acceleration sensors include an MEMS tri-axial acceleration sensor or three mono-axial acceleration sensors disposed in three-axis directions perpendicular to each other.

20. A program causing a computer of an electronic apparatus to execute a sequence of calculating a magnitude of an acceleration in at least one of three separate directions and calculating a synthesized value indicating the magnitudes of the accelerations in the three directions based on the calculated magnitude of the acceleration and the acceleration in the direction separate from at least one of the directions.