METHOD FOR CONTROLLING A PEDOMETER BASED ON THE USE OF INERTIAL SENSORS AND PEDOMETER IMPLEMENTING THE METHOD

• US 20070143069A1
• Filed: 10/02/2006
• Published: 06/21/2007
• Est. Priority Date: 10/03/2005
• Status: Active Grant

• Current Assignee: STMicroelectronics SRL (STMicroelectronics NV)
• Original Assignee: STMicroelectronics SRL (STMicroelectronics NV)
• Inventors: Binda, Ivo, Pasolini, Fabio
• Granted Patent: US 7,698,097 B2
• Time in Patent Office: Days
• US Class Current: 702/160
• CPC Class Codes: G01C 22/006 Pedometers

Abstract

A method for controlling a pedometer includes the steps of: generating a signal correlated to movements of a user of the pedometer; and detecting steps of the user on the basis of the signal. The method moreover envisages the steps of checking whether sequences of detected steps satisfy pre-determined conditions of regularity; updating a total number of valid steps if the conditions of regularity are satisfied; and preventing the updating of the total number of valid steps if the conditions of regularity are not satisfied.

Claims

1. A method for controlling a pedometer, comprising the steps of:

generating a signal correlated to movements of a user of the pedometer;

detecting steps of the user based on said signal;

checking whether sequences of the detected steps satisfy conditions of regularity;

updating a total number of valid steps if said conditions of regularity are satisfied; and

preventing updating of said total number of valid steps if said conditions of regularity are not satisfied.

2. The method according to claim 1, wherein said step of checking whether sequences of steps detected satisfy pre-determined conditions of regularity comprises:

in a first operating condition, checking whether a first condition of regularity is satisfied; and

in a second operating condition, checking whether a second condition of regularity is satisfied.

3. The method according to claim 2, wherein, during said step of checking whether said first condition of regularity is satisfied, the updating of said total number of valid steps is prevented.

4. The method according to claim 2, wherein, during said step of checking whether said second condition of regularity is satisfied, the updating of said total number of valid steps is allowed.

5. The method according to claim 3, wherein said step of checking whether said first condition of regularity is satisfied comprises:

executing a first validation test of a current detected step;

incrementing a number of valid control steps if based on said first validation test said current detected step is validated; and

incrementing a number of invalid steps and decrementing said number of valid control steps if based on said first validation test said current detected step is not validated.

6. The method according to claim 5, wherein said step of executing said first validation test of said current detected step comprises evaluating whether a first duration of said current detected step is homogeneous with respect to a second duration of an immediately preceding detected step.

7. The method according to claim 6, wherein said first validation test yields a positive result when an instant of recognition of the current detected step TR(K) falls within a validation interval, defined with respect to an instant of recognition of the immediately preceding detected step T_R(K−

1), in the following way;

TV=[T_R(K−

1)+Δ

T<sub>K−

1</sub>−

TA, T_R(K−

1)+Δ

T<sub>K−

1</sub>+TB]

where Δ

T<sub>K−

1</sub> is said second duration, and TA and TB are complementary portions of said validation interval.

8. The method according to claim 5, wherein said step of checking whether said first condition of regularity is satisfied comprises comparing said number of invalid steps with a first threshold number and comparing said number of valid control steps with a second threshold number.

9. The method according to claim 8, wherein said first condition of regularity is satisfied if said number of valid control steps is equal to said second threshold number.

10. The method according to claim 8, wherein said step of checking whether said second condition of regularity is satisfied comprises:

executing a second validation test of said current detected step;

incrementing said number of valid control steps and said total number of valid steps if based on said second validation test said current detected step is validated; and

incrementing a number of invalid steps if based on said second validation test said current detected step is not validated.

11. The method according to claim 10, wherein said step of checking whether said second condition of regularity is satisfied comprises comparing said number of valid control steps with a third threshold number and comparing said number of invalid steps with a fourth threshold number.

12. The method according to claim 11, wherein said second condition of regularity is satisfied if said number of invalid steps is smaller than said fourth threshold number.

13. The method according to claim 12, comprising the step of incrementing said total number of valid steps and decrementing said number of valid control steps if, on the basis of said second validation test, said current detected step is not validated and said number of invalid steps is smaller than said fourth threshold number.

14. The method according to claim 1, comprising the step of setting said pedometer in a third operating condition, wherein said pedometer is at least partially de-activated, if said step of detecting steps of the user on the basis of said signal fails for a period longer than a time threshold.

15. A pedometer, comprising:

an inertial sensor structured to generate a signal correlated to movements of a user of the pedometer; and

a control unit coupled to said inertial sensor, said control unit including;

detecting means for detecting steps of the user based on said signal;

checking means for checking whether sequences of the detected steps satisfy conditions of regularity;

updating means for updating a total number of valid steps if said conditions of regularity are satisfied; and

preventing means for preventing updating of said total number of valid steps if said conditions of regularity are not satisfied.

16. The pedometer according to claim 15, wherein said checking means includes:

means for executing a first validation test of a current detected step by evaluating whether a first duration of said current detected step is homogeneous with respect to a second duration of an immediately preceding detected step;

first incrementing means for incrementing a number of valid control steps if based on said first validation test said current detected step is validated; and

second incrementing means for incrementing a number of invalid steps if based on said first validation test said current detected step is not validated.

17. The pedometer according to claim 16, wherein said first validation test yields a positive result when an instant of recognition of the current detected step T_R(K) falls within a validation interval, defined with respect to an instant of recognition of the immediately preceding detected step T_R(K−

1), in the following way;

TV=[T_R(K−

1)+Δ

T<sub>K−

1</sub>−

TA, T_R(K−

1)+Δ

T<sub>K−

1</sub>+TB]

where Δ

T<sub>K−

1</sub> is said second duration, and TA and TB are complementary portions of said validation interval.

18. The pedometer according to claim 15, wherein said checking means include means for executing a first validation test of a current detected step by comparing said number of invalid steps with a first threshold number and comparing said number of valid control steps with a second threshold number.

19. The pedometer according to claim 18, wherein said first condition of regularity is satisfied if said number of valid control steps is equal to said second threshold number.

20. The pedometer according to claim 18, wherein said checking means checks whether said second condition of regularity is satisfied by:

executing a second validation test of said current detected step;

incrementing said number of valid control steps and said total number of valid steps if based on said second validation test said current detected step is validated; and

incrementing a number of invalid steps if based on said second validation test said current detected step is not validated.

21. A portable electronic device, comprising:

a user interface that enables communication with a user; and

an inertial sensor structured to generate a signal correlated to movements of the user; and

a control unit coupled to said inertial sensor, said control unit including;

detecting means for detecting steps of the user based on said signal;

checking means for checking whether sequences of the detected steps satisfy conditions of regularity;

updating means for updating a total number of valid steps if said conditions of regularity are satisfied; and

preventing means for preventing updating of said total number of valid steps if said conditions of regularity are not satisfied.

22. The device according to claim 21, wherein said checking means includes:

means for executing a first validation test of a current detected step by evaluating whether a first duration of said current detected step is homogeneous with respect to a second duration of an immediately preceding detected step;

first incrementing means for incrementing a number of valid control steps if based on said first validation test said current detected step is validated; and

second incrementing means for incrementing a number of invalid steps if based on said first validation test said current detected step is not validated.

23. The device according to claim 22, wherein said first validation test yields a positive result when an instant of recognition of the current detected step T_R(K) falls within a validation interval, defined with respect to an instant of recognition of the immediately preceding detected step T_R(K−

1), in the following way;

TV=[T_R(K−

1)+Δ

T<sub>K−

1</sub>−

TA, T_R(K−

1)+Δ

T<sub>K−

1</sub>+TB]

where Δ

T<sub>K−

1</sub> is said second duration, and TA and TB are complementary portions of said validation interval.

24. The device according to claim 21, wherein said checking means include means for executing a first validation test of a current detected step by comparing said number of invalid steps with a first threshold number and comparing said number of valid control steps with a second threshold number.

25. The device according to claim 24, wherein said first condition of regularity is satisfied if said number of valid control steps is equal to said second threshold number.

26. The device according to claim 24, wherein said checking means checks whether said second condition of regularity is satisfied by:

executing a second validation test of said current detected step;

incrementing said number of valid control steps and said total number of valid steps if based on said second validation test said current detected step is validated; and

incrementing a number of invalid steps if based on said second validation test said current detected step is not validated.

27. The device according to claim 21 wherein the device is a mobile phone.