Method and device for measuring the progress of a moving person

• US 20080255800A1
• Filed: 12/19/2007
• Published: 10/16/2008
• Est. Priority Date: 04/13/2007
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: VTI Technologies Oy (Murata Manufacturing Co Limited)
• Inventors: Meriheina, Ulf, Lahtinen, Juha
• Granted Patent: US 9,518,828 B2
• Time in Patent Office: Days
• US Class Current: 702/160
• CPC Class Codes: A63B 2220/17 Counting, e.g. counting periodical movements, revolutions or cycles, or including further data processing to determine distances or speed
• CPC Class Codes: A63B 2220/40 Acceleration
• CPC Class Codes: A63B 2220/803 Motion sensors
• CPC Class Codes: A63B 24/00 Electric or electronic controls for exercising apparatus of preceding groups; Controlling or monitoring of exercises, sportive games, training or athletic performances
• CPC Class Codes: A63B 69/0028 for running, jogging or speed-walking movable endless bands A63B22/02
• CPC Class Codes: G01C 21/1654 with electromagnetic compass
• CPC Class Codes: G01C 21/185 for gravity
• CPC Class Codes: G01C 22/006 Pedometers

Abstract

The invention relates to measuring devices to be used in physical measuring, and more particularly, to a method and a device for measuring the progress of a moving person. In the solution according to the invention the quantities describing the progress of the moving person are being calculated based on step cycle-specific acceleration stage characteristic accelerations a+ and step cycle-specific braking stage characteristic acceleration a− obtained from acceleration values measured by means of an acceleration sensor, and on the measured time. The invention aims at providing a solution, better and simpler than prior solutions, for measuring the progress of a moving person, which solution is applicable for use in a multitude of measuring solutions for ways of locomotion of various types.

Claims

1. A method for measuring the progress of a moving person, characterized in that at least one of the following quantities describing the progress of the moving person:

speed, step rate, step count, step length, distance and way of progress, is calculated based on step cycle-specific acceleration stage characteristic accelerations a+ and braking stage characteristic accelerations a−

obtained from acceleration values measured by means of an acceleration sensor, and on the measured time.

2. Method according to claim 1, characterized in that the step cycle-specific acceleration stage characteristic accelerations a+ are obtained as the maxima of the step cycle-specific measured acceleration values and braking stage characteristic accelerations a−

are obtained as the minima of the step cycle-specific measured acceleration values.

3. Method according to claim 1, characterized in that the step cycle-specific acceleration stage characteristic accelerations a+ are obtained as the maxima for each step cycle of the analogically filtered acceleration sensor signals a_in and braking stage characteristic accelerations a−

are obtained as the minima for each step cycle of the analogically filtered acceleration sensor signals a_in.

4. Method according to claim 1, characterized in that the step cycle-specific acceleration stage characteristic accelerations a+ are obtained as the maxima for each step cycle of the digitally filtered acceleration sensor signals a_in and braking stage characteristic accelerations a−

are obtained as the minima for each step cycle of the digitally filtered acceleration sensor signals a_in.

5. Method according to claim 1, characterized in that the step cycle-specific acceleration stage characteristic accelerations a+ are obtained as mean values for each step cycle of the digitally filtered acceleration sensor signals a_in over times selected during the positive half-cycle and braking stage characteristic accelerations a−

are obtained as mean values for each step cycle of the digitally filtered acceleration sensor signals a_in over times selected during the negative half-cycle.

6. Method according to claim 4, characterized in that the function used in the digital filtering is:

a_out=a_in/√

{square root over ([1+(f/f₀)²])},

where f is the frequency and f₀ is a suitably selected boundary frequency.

7. Method according to claim 1, characterized in that the step cycle-specific acceleration stage characteristic accelerations a+ are obtained as the maxima for each step cycle of the signals a_in from the acceleration sensor filtered with digital weighting and braking stage characteristic accelerations a−

are obtained as the minima for each step cycle of the signals a_in from the acceleration sensor filtered with digital weighting.

8. Method according to claim 1, characterized in that the step cycle-specific acceleration stage characteristic accelerations a+ are obtained as mean values for each step cycle of the signals a_in from the acceleration sensor filtered with digital weighting over times selected during the positive half-cycle and braking stage characteristic accelerations a−

are obtained as mean values for each step cycle of the signals a_in from the acceleration sensor filtered with digital weighting over times selected during the negative half-cycle.

9. Method according to claim 7, characterized in that the function used in the digital weighted filtering is:

a_out(n)=(1−

k)*a_out(n−

1)+a_in*k,

where n indicates the n;

th sample and k is the weighting factor.

10. Method according to claim 1, characterized in that the speed v is being computed based on the characteristic acceleration values a+ and/or a−

as follows;

v=f(a+)=k*|a+|, or

v=f(a−

)=k*|a−

|,

where k is a constant.

11. Method according to claim 1, characterized in that in calculating the quantities describing the progress of the moving person, the time used up in one pair of steps Δ

t_pos is obtained as the time interval between two equivalent points, such as a maximum, a minimum, or a point of exceeding or falling below a certain value, on the acceleration graph given by the measured acceleration values.

12. Method according to claim 11, characterized in, that the step length s_step or the length of a pair of steps s_pos is calculated using the formula:

13. Method according to claim 11, characterized in that the rate of pairs of steps f_pos, or the step rate f_step, are calculated using the formula:

f_pos=1/Δ

t_pos or f_step=2/Δ

t_pos.

14. Method according to claim 12, characterized in that the step count n is calculated on the basis of the number n of equivalent points, such as a maximum, a minimum, or a point of exceeding or falling below a certain value, on the acceleration graph given by the measured acceleration values.

15. Method according to claim 12, characterized in that the distance covered s is calculated as the sum of the lengths of the steps or the pairs of steps:

16. Method according to claim 1, characterized in that the method distinguishes between ways of progress, such as walking, running, and skiing, based on acceleration maximum and minimum, the characteristic acceleration values a+ and a−

, and/or the step rate.

17. Method according to claim 16, characterized in that the method makes an individual calibration for each way of locomotion, such as running, walking, pole walking, or cross-country skiing.

18. Method according to claim 1, characterized in that the method is applied for use in step-by-step navigation.

24. Device according to claim 4, characterized in that the device is adapted to use the following function in the digital filtering:

a_out=a_in/√

{square root over ([1+(f/f₀)²])},

where f is the frequency and f₀ is a suitably selected boundary frequency.

19. A device for measuring the progress of a moving person, characterized in that the device is adapted to measure acceleration and time in such a way, that at least one of the following quantities describing the progress of the moving person:

speed, step rate, step count, step length, distance and manner of locomotion, is calculated based on a step-cycle-specific acceleration stage characteristic accelerations a+ and braking stage characteristic accelerations a−

obtained from acceleration values measured by an acceleration sensor, and on the measured time.

20. Device according to claim 19, characterized in that the device is adapted to determine the step-cycle-specific acceleration stage characteristic accelerations a+ as the maxima for each step cycle of the measured acceleration values and braking stage characteristic accelerations a−

as the minima for each step cycle of the measured acceleration values.

21. Device according to claim 19, characterized in that the device is adapted to determine the step-cycle-specific acceleration stage characteristic accelerations a+ as the maxima for each step cycle of the analogically filtered acceleration sensor signals a_in and braking stage characteristic accelerations a−

as the minima for each step cycle of the analogically filtered acceleration sensor signals a_in.

22. Device according to claim 19, characterized in that the device is adapted to determine the step-cycle-specific acceleration stage characteristic accelerations a+ as the maxima for each step cycle of the digitally filtered acceleration sensor signals a_in and braking stage characteristic accelerations a−

as the minima for each step cycle of the digitally filtered acceleration sensor signals a_in.

23. Device according to claim 19, characterized in that the device is adapted to determine the step-cycle-specific acceleration stage characteristic accelerations a+ as mean values for each step cycle of the digitally filtered acceleration sensor signals a_in over times selected during the positive half-cycle and braking stage characteristic accelerations a−

as mean values for each step cycle of the digitally filtered acceleration sensor signals a_in over times selected during the negative half-cycle.

25. Device according to claim 19, characterized in that the device is adapted to determine the step cycle-specific acceleration stage characteristic accelerations a+ as the maxima for each step cycle of the signals a_in from the acceleration sensor filtered with digital weighting and braking stage characteristic accelerations a−

as the minima for each step cycle of the signals a_in from the acceleration sensor filtered with digital weighting.

26. Device according to claim 19, characterized in that the device is adapted to determine the step cycle-specific acceleration stage characteristic accelerations a+ as mean values for each step cycle of the signals a_in from the acceleration sensor filtered with digital weighting over times selected during the positive half-cycle, and acceleration stage characteristic accelerations a−

as mean values for each step cycle of the signals a_in from the acceleration sensor filtered with digital weighting over times selected during the negative half-cycle.

27. Device according to claim 25, characterized in that the device is adapted to use this function in the digital weighted filtering:

a_out(n)=(1−

k)a_out(n−

1)+a_in*k,

where n indicates the n;

th sample and k is the weighting factor.

28. Device according to claim 19, characterized in that the device is adapted to calculate the speed v based on the characteristic accelerations a+ and/or a−

as follows;

v=f(a+)=k*|a+|, or

v=f(a−

)=k*|a−

|,

where k is a constant.

29. Device according to claim 19, characterized in that the device is adapted to determine the time used up in one pair of steps Δ

t_pos as the time interval between two equivalent points, such as a maximum, a minimum, or a point of exceeding or falling below a certain value, on the acceleration graph given by the measured acceleration values.

30. Device according to claim 29, characterized in that the device is adapted to calculate the step length s_step or the length of one pair of steps s_pos using the formula:

31. Device according to claim 29, characterized in that the device is adapted to calculate the rate of pairs of steps f_pos or the step rate f_step using the formula:

f_pos=1/Δ

t_pos or f_step=2/Δ

t_pos.

32. Device according to claim 30, characterized in that the device is adapted to calculate the step count n on the basis of the number n of equivalent points, such as a maximum, a minimum, or a point of exceeding or falling below a certain value, on the acceleration graph given by the measured acceleration values.

33. Device according to claim 30, characterized in that the device is adapted to calculate the distance covered s as the sum of the lengths of the steps or of the pairs of steps:

34. Device according to claim 19, characterized in that the device is adapted to distinguish between ways of progress, such as walking, running, and skiing, based on acceleration maximum and minimum, the characteristic acceleration values a+ and a−

and/or the step rate.

35. Device according to claim 34, characterized in that the device is adapted to make an individual calibration for each way of progress, such as running, walking, pole walking, or cross-country skiing.

36. Device according to claim 19, characterized in that the device is adapted to be used in step-by-step navigation.

37. Device according to claim 36, characterized in that the device is adapted to cooperate with an altimeter, satellite navigation devices, and/or a magnetometer.

38. Device according to claim 36, characterized in that the device is adapted to receive and/or utilize data in map databases and/or terrain inclination data.

39. A piece of footwear, characterized in that the piece of footwear comprises a device according to claim 19 for measuring the progress of a moving person.

40. A device to be positioned at a moving person'"'"'s middle, characterized in that the device comprises a device according to claim 19 for measuring the progress of the moving person.

41. A device to be positioned at a moving person'"'"'s arm, characterized in that the device comprises a device according to claim 19 for measuring the progress of the moving person.

42. A display unit for a moving person, characterized in that the display unit for the moving person is adapted to cooperate with a device according to claim 19 measuring the progress of the moving person.

43. A system for measuring the progress of a moving person, characterized in that the system comprises a device according to claim 19 for measuring the progress of the moving person and a display unit for the moving person adapted to cooperate with this device.

44. System according to claim 43, characterized in that said device for measuring the progress of the moving person and said display unit for the moving person are integrated into one device.