Storage medium having step count calculation program stored therein, step count calculation apparatus, and step count calculation system

• US 20090144020A1
• Filed: 02/01/2008
• Published: 06/04/2009
• Est. Priority Date: 11/30/2007
• Status: Active Grant

• Current Assignee: Nintendo Company Limited
• Original Assignee: Nintendo Company Limited
• Inventors: Sato, Kenta, Ohta, Keizo
• Granted Patent: US 7,684,958 B2
• Time in Patent Office: Days
• US Class Current: 702/160
• CPC Class Codes: G01C 22/006 Pedometers

Abstract

By repeatedly obtaining acceleration data, a gravity direction acceleration acting in a gravity direction of a housing and a horizontal direction acceleration acting in a horizontal direction perpendicular to the gravity direction are calculated. By using a first coefficient, a first step count in accordance with a change in the gravity direction acceleration is calculated and by using a second coefficient which is different from the first coefficient, a second step count in accordance with a change in the horizontal direction acceleration is calculated. Based on a predetermined condition, one of the first step count and the second step count is selected as a user'"'"'s step count.

Claims

1. A computer-readable storage medium having stored therein a step count calculation program which is executed by a computer in an apparatus for, by using acceleration data outputted from an acceleration sensor for detecting accelerations acting on a given housing, calculating a number of steps made by a user carrying the housing, the computer-readable storage medium having stored therein the step count calculation program which causes the computer to function as:

acceleration data obtaining means for repeatedly obtaining the acceleration data;

gravity direction acceleration calculation means for, by using the acceleration data obtained by the acceleration data obtaining means, calculating a gravity direction acceleration acting in a gravity direction of the housing;

horizontal direction acceleration calculation means for, by using the acceleration data obtained by the acceleration data obtaining means, calculating a horizontal direction acceleration acting in a horizontal direction perpendicular to the gravity direction of the housing;

first step count calculation means for, by using a first coefficient, calculating a first step count in accordance with a change in the gravity direction acceleration;

second step count calculation means for, by using a second coefficient which is different from the first coefficient, calculating a second step count in accordance with a change in the horizontal direction acceleration; and

step count selection means for, based on a predetermined condition, selecting one of the first step count and the second step count as a user'"'"'s step count.

2. The computer-readable storage medium having stored therein the step count calculation program, according to claim 1, further causing the computer to function as gravity direction calculation means for, by using the acceleration data obtained by the acceleration data obtaining means, calculating the gravity direction of the housing,

wherein the gravity direction acceleration calculation means, based on the gravity direction calculated by the gravity direction calculation means, calculates, as the gravity direction acceleration, components of the gravity direction of the acceleration indicated by the acceleration data obtained by the acceleration data obtaining means, and

wherein based on the gravity direction obtained by the gravity direction calculation means, the horizontal direction acceleration calculation means calculates, as the horizontal direction acceleration, components of the horizontal direction of the acceleration indicated by the acceleration data obtained by the acceleration data obtaining means.

3. The computer-readable storage medium having stored therein the step count calculation program, according to claim 2,

wherein the first step count calculation means, in accordance with a period in which the gravity direction acceleration increases or decreases, calculates the first step count, and

wherein the second step count calculation means, in accordance with a period in which the horizontal direction acceleration increases or decreases, calculates the second step count.

4. The computer-readable storage medium having stored therein the step count calculation program, according to claim 3,

wherein the first coefficient and the second coefficient are values determined on a condition that the period in which the horizontal direction acceleration increases or decreases is double the period in which the gravity direction acceleration increases or decreases.

5. The computer-readable storage medium having stored therein the step count calculation program, according to claim 3,

wherein the first step count calculation means calculates as the first step count a step count which follows at a predetermined rate the step count per unit time, which is calculated based on the period in which the gravity direction acceleration increases or decreases, and

wherein the second step count calculation means calculates as the second step count a step count which follows at a predetermined rate the step count per unit time, which is calculated based on the period in which the horizontal direction acceleration increases or decreases.

6. The computer-readable storage medium having stored therein the step count calculation program, according to claim 3,

wherein the first step count calculation means includes first attenuation means for attenuating the first step count calculated in previous processing in a case where the period in which the gravity direction acceleration increases or decreases is longer than a predetermined threshold value, and

wherein the second step count calculation means includes second attenuation means for attenuating the second step count calculated in the previous processing in a case where the period in which the horizontal direction acceleration increases or decreases is longer than a predetermined threshold value.

7. The computer-readable storage medium having stored therein the step count calculation program, according to claim 3,

wherein the first step count calculation means includes first local maximum detection means for detecting local maximums obtained when the gravity direction acceleration increases or decreases,

wherein the second step count calculation means includes second local maximum detection means for detecting local maximums obtained when the horizontal direction acceleration increases or decreases,

wherein the first step count calculation means calculates the first step count in accordance with a time interval between the local maximums detected by the first local maximum detection means, and

wherein the second step count calculation means calculates the second step count in accordance with a time interval between the local maximums detected by the second local maximum detection means.

8. The computer-readable storage medium having stored therein the step count calculation program, according to claim 7,

wherein the first step count calculation means calculates the first step count by dividing the first coefficient by the time interval between the local maximums detected by the first local maximum detection means,

wherein the second step count calculation means calculates the second step count by dividing the second coefficient by the time interval between the local maximums detected by the second local maximum detection means, and

wherein the second coefficient is double the first coefficient.

9. The computer-readable storage medium having stored therein the step count calculation program, according to claim 7,

wherein the first local maximum detection means detects the local maximums obtained when an absolute value of the gravity direction acceleration increases or decreases, and

wherein the second local maximum detection means detects the local maximums obtained when a magnitude of the horizontal direction acceleration increases or decreases.

10. The computer-readable storage medium having stored therein the step count calculation program, according to claim 7,

wherein the first local maximum detection means detects only local maximums, among the local maximums obtained when the gravity direction acceleration increases or decreases, which are greater than or equal to a predetermined reference value, and

wherein the second local maximum detection means detects only local maximums, among the local maximums obtained when the horizontal direction acceleration increases or decreases, which are greater than or equal to a predetermined reference value.

11. The computer-readable storage medium having stored therein the step count calculation program, according to claim 3,

wherein the first step count calculation means includes:

first local maximum detection means for detecting local maximums obtained when the gravity direction acceleration increases or decreases; and

first time interval prediction means for, in accordance with a magnitude of the gravity direction acceleration, predicting a time interval from a time point when the first local maximum detection means detects an immediately preceding local maximum to a time point when the first local maximum detection means detects a next local maximum,

wherein the second step count calculation means includes;

second local maximum detection means for detecting local maximums obtained when the horizontal direction acceleration increases or decreases; and

second time interval prediction means for, in accordance with a magnitude of the horizontal direction acceleration, predicting a time interval from a time point when the second local maximum detection means detects an immediately preceding local maximum to a time point when the second local maximum detection means detects a next local maximum,

wherein the first step count calculation means calculates the first step count in accordance with the time interval predicted by the first time interval prediction means, and

wherein the second step count calculation means calculates the second step count in accordance with the time interval predicted by the second time interval prediction means.

12. The computer-readable storage medium having stored therein the step count calculation program, according to claim 1,

wherein the first time interval prediction means predicts the time interval by using a magnitude of the immediately preceding local maximum detected by the first local maximum detection means and a change amount of a value of the gravity direction acceleration, and

wherein the second time interval prediction means predicts the time interval by using a magnitude of the immediately preceding local maximum detected by the second local maximum detection means and a change amount of a value of the horizontal direction acceleration.

13. The computer-readable storage medium having stored therein the step count calculation program, according to claim 1,

wherein the step count selection means compares the first step count and the second step count and selects to use one of the first step count and the second step count, whichever is larger than another of the first step count and the second step count.

14. The computer-readable storage medium having stored therein the step count calculation program, according to claim 1,

wherein the step count selection means includes:

first amplitude detection means for detecting a first amplitude at which the gravity direction acceleration increases or decreases;

second amplitude detection means for detecting a second amplitude at which the horizontal direction acceleration increases or decreases; and

ratio calculation means for calculating a ratio between the first amplitude and the second amplitude, and

wherein when the first amplitude is larger than an amplitude which is obtained by multiplying the second amplitude by a predetermined ratio, the step count selection means selects to use the first step count, and when the first amplitude is less than or equal to the amplitude which is obtained by multiplying the second amplitude by the predetermined ratio, the step count selection means selects to use the second step count.

15. The computer-readable storage medium having stored therein the step count calculation program, according to claim 1,

wherein the step count selection means includes accumulated step count calculation means for calculating an accumulated step count by sequentially accumulating one of the selected first step count and the selected second step count.

16. The computer-readable storage medium having stored therein the step count calculation program, according to claim 2,

wherein the gravity direction calculation means calculates, as the gravity direction of the housing, a direction of a vector which follows at a predetermined rate a vector of the acceleration indicated by the acceleration data obtained by the acceleration data obtaining means.

17. The computer-readable storage medium having stored therein the step count calculation program, according to claim 16,

wherein based on the gravity direction calculated by the gravity direction calculation means, the gravity direction acceleration calculation means calculates, as the gravity direction acceleration, components of the gravity direction obtained after the following vector has been subtracted from the vector of the acceleration indicated by the acceleration data obtained by the acceleration data obtaining means, and

wherein based on the gravity direction calculated by the gravity direction calculation means, the horizontal direction acceleration calculation means calculates, as the horizontal direction acceleration, components of the horizontal direction of the acceleration obtained after the following vector has been subtracted from the vector of the acceleration indicated by the acceleration data obtained by the acceleration data obtaining means.

18. A step count calculation apparatus for calculating a number of steps made by a user carrying the step count calculation apparatus, comprising:

an acceleration sensor for detecting accelerations acting on an apparatus body and for outputting acceleration data;

a display section provided on the apparatus body;

acceleration data obtaining means for repeatedly obtaining the acceleration data;

gravity direction acceleration calculation means for, by using the acceleration data obtained by the acceleration data obtaining means, calculating a gravity direction acceleration acting in a gravity direction of the apparatus body;

horizontal direction acceleration calculation means for, by using the acceleration data obtained by the acceleration data obtaining means, calculating a horizontal direction acceleration acting in a horizontal direction perpendicular to the gravity direction of the apparatus body;

first step count calculation means for, by using a first coefficient, calculating a first step count in accordance with a change in the gravity direction acceleration;

second step count calculation means for, by using a second coefficient which is different from the first coefficient, calculating a second step count in accordance with a change in the horizontal direction acceleration;

step count selection means for, based on a predetermined condition, selecting one of the first step count and the second step count as a user'"'"'s step count; and

display control means for displaying, on the display section, information in accordance with the step count selected by the step count selection means.

19. A step count calculation system, including a hand-held unit which is capable of being carried by a user and a body unit which is connected to the hand-held unit via one of wired communication and wireless communication, for calculating a step count made by the user carrying the hand-held unit, the step count calculation system comprising:

an acceleration sensor for detecting accelerations acting on a body of the hand-held unit and for outputting acceleration data;

acceleration data obtaining means for obtaining the acceleration data from the acceleration sensor;

gravity direction acceleration calculation means for, by using the acceleration data obtained by the acceleration data obtaining means, calculating a gravity direction acceleration acting in a gravity direction of the hand-held unit;

horizontal direction acceleration calculation means for, by using the acceleration data obtained by the acceleration data obtaining means, calculating a horizontal direction acceleration acting in a horizontal direction perpendicular to the gravity direction of the hand-held unit;

first step count calculation means for, by using a first coefficient, calculating a first step count in accordance with a change in the gravity direction acceleration;

second step count calculation means for, by using a second coefficient which is different from the first coefficient, calculating a second step count in accordance with a change in the horizontal direction acceleration;

step count selection means for, based on a predetermined condition, selecting one of the first step count and the second step count as a user'"'"'s step count; and

display control means for displaying, on the display section, information in accordance with the step count selected by the step count selection means.