EXERCISE SUPPORT DEVICE, EXERCISE SUPPORT METHOD, AND EXERCISE SUPPORT PROGRAM

• US 20150081245A1
• Filed: 09/17/2014
• Published: 03/19/2015
• Est. Priority Date: 09/19/2013
• Status: Active Grant

• Current Assignee: Casio Computer Company Limited
• Original Assignee: Casio Computer Company Limited
• Inventors: NAGASAKA, Tomoaki
• Granted Patent: US 9,939,456 B2
• Time in Patent Office: Days
• US Class Current: 702/141
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 5/1126 using a particular sensing technique
• CPC Class Codes: G01P 3/64 Devices characterised by the determination of the time taken to traverse a fixed distance
• CPC Class Codes: G06F 2218/12 Classification; Matching
• CPC Class Codes: G06V 40/23 Recognition of whole body movements, e.g. for sport training
• CPC Class Codes: G16H 20/30 relating to physical therapies or activities, e.g. physiotherapy, acupressure or exercising

Abstract

In an exercise support device of the present invention, acceleration signals in three axis directions including vertical, longitudinal, and lateral directions corresponding to the motion of a user performing exercise of cyclically moving feet are obtained, and a first maximum value in one cycle of a foot movement in the vertical acceleration signal is obtained. Subsequently, a search is made for first and second change points related to foot landing and takeoff motions in a composite acceleration signal obtained by combining acceleration signals in at least two axis directions, in forward and backward directions of the time point of a second maximum value of the composite acceleration signal, within the cycle. Then, a time period between the first and second change points is obtained as a change point interval, and a foot landing period while exercising is calculated based on the first maximum value and the change point interval.

Claims

1. An exercise support device comprising:

an acceleration measuring section which obtains acceleration signals in three axis directions including a vertical direction, a longitudinal direction, and a lateral direction corresponding to a motion of a body of a user performing exercise of cyclically moving feet;

a vertical acceleration maximum value obtaining section which obtains a first maximum value within a period of one cycle of a foot movement of the user in an acceleration signal in the vertical direction obtained by the acceleration measuring section;

a signal processing section which searches for a first change point related to foot landing and takeoff motions of the user in a composite acceleration signal obtained by combining acceleration signals in at least two of the three axis directions, in a forward direction of a time point of a second maximum value of the composite acceleration signal, and searches for a second change point related to foot landing and takeoff motions of the user in the composite acceleration signal, in a backward direction of the time point of the second maximum value, within the period of one cycle; and

a landing period calculating section which obtains a period of time between the first change point and the second change point as a change point interval, when the first change point and the second change point are detected by search in the signal processing section, and calculates a foot landing period of the user while exercising based on the first maximum value of the acceleration signal in the vertical direction and the change point interval.

2. The exercise support device according to claim 1, wherein the landing period calculating section calculates the foot landing period by an equation T=a×

P+b×

W+c×

P×

W where the foot landing period is T, the first maximum value is P, the change point interval is W, a and b are positive constants, and c is a negative constant.

3. The exercise support device according to claim 1, wherein the landing period calculating section calculates the foot landing period based on the first maximum value of the acceleration signal in the vertical direction, when at least one of the first change point and the second change point is not detected by the signal processing section.

4. The exercise support device according to claim 3, wherein the landing period calculating section calculates the foot landing period by an equation of foot landing period T=d×

(1/P) where the foot landing period is T, the first maximum value is P, and d is a positive constant.

5. The exercise support device according to claim 1, wherein the acceleration signals in the two axis directions for generating the composite acceleration signal are the acceleration signal in the vertical direction and an acceleration signal in the longitudinal direction.

6. The exercise support device according to claim 1, wherein the signal processing section searches for a minimum value equal to or smaller than a predetermined threshold value in the forward direction and the backward direction of the time point of the second maximum value of the composite acceleration signal, and obtains, when at least one minimum value is found in each of the forward direction and the backward direction of the time point of the second maximum value, a first minimum value of found minimum values which is positioned closest to time progress to the second maximum value in the forward direction of the second maximum value as the first change point, and a second minimum value which is positioned closest to time progress to the second maximum value in the backward direction of the second maximum value as the second change point, and

wherein the landing period calculating section obtains a period of time between the first minimum value and the second minimum value as the change point interval.

7. The exercise support device according to claim 1, further comprising:

an axis correcting section which corrects values of the acceleration signals of each axis by rotating each axis of the acceleration signals such that the acceleration signal in the vertical direction obtained by the acceleration measuring section coincides with a gravity direction,

wherein the vertical acceleration maximum value obtaining section obtains the first maximum value of the acceleration signal in the vertical direction based on the acceleration signals corrected by the axis correcting section, and

wherein the signal processing section searches for the first change point and the second change point based on the acceleration signals corrected by the axis correcting section.

8. The exercise support device according to claim 7, further comprising:

an angular velocity measuring section which obtains angular velocity signals in rotating directions of three axes of the user while exercising,

wherein the axis correcting section estimates the gravity direction based on the angular velocity signals obtained by the angular velocity measuring section and corrects the values of the acceleration signals.

9. The exercise support device according to claim 1, further comprising:

a judging section which compares the foot landing period calculated by the landing period calculating section with a predetermined reference value, and generates a notification signal in accordance with a comparison result; and

an information providing section which provides the user with predetermined exercise support information based on the notification signal.

10. The exercise support device according to claim 9, wherein the acceleration measuring section, the storage section, the vertical acceleration maximum value obtaining section, the signal processing section, the landing period calculating section, the judging section, and the information providing section are directly or indirectly connected to a network,

wherein the vertical acceleration maximum value obtaining section, the signal processing section, and the landing period calculating section obtain the first maximum value of the acceleration signal in the vertical direction, search for the first change point and the second change point of the composite acceleration signal, and calculate the foot landing period, respectively, based on the acceleration signals received via the network, and

wherein the information providing section provides the user with the exercise support information based on the notification signal in accordance with at least a result of judgment by the judging section received via the network.

11. The exercise support device according to claim 1, further comprising:

a storage section which stores the acceleration signals obtained by the acceleration measuring section as needed,

wherein the vertical acceleration maximum value obtaining section, the signal processing section, and the landing period calculating section obtain the first maximum value of the acceleration signal in the vertical direction, search for the first change point and the second change point, and calculate the foot landing period, respectively, based on the acceleration signals stored in the storage section after end of the exercise.

12. An exercise support method comprising:

a step of obtaining acceleration signals in three axis directions including a vertical direction, a longitudinal direction, and a lateral direction corresponding to a motion of a body of a user performing exercise of cyclically moving feet;

a step of obtaining a first maximum value within a period of one cycle of a foot movement of the user in an acceleration signal in the vertical direction;

a step of searching for a first change point related to foot landing and takeoff motions of the user in a composite acceleration signal obtained by combining acceleration signals in at least two of the three axis directions, in a forward direction of a time point of a second maximum value of the composite acceleration signal, and searching for a second change point related to foot landing and takeoff motions of the user in the composite acceleration signal, in a backward direction of the time point of the second maximum value, within the period of one cycle; and

a step of obtaining a period of time between the first change point and the second change point as a change point interval, when the first change point and the second change point are detected in the step of searching for the first change point and the second change point, and calculating a foot landing period of the user while exercising based on the first maximum value of the acceleration signal in the vertical direction and the change point interval.

13. The exercise support method according to claim 12, wherein the foot landing period in the step of calculating the foot landing period is calculated by an equation T=a×

P+b×

W+c×

P×

W where the foot landing period is T, the first maximum value is P, the change point interval is W, a and b are positive constants, and c is a negative constant.

14. The exercise support method according to claim 12, further comprising:

a step of calculating the foot landing period based on the first maximum value of the acceleration signal in the vertical direction, when at least one of the first change point and the second change point is not detected in the step of searching for the first change point and the second change point.

15. The exercise support method according to claim 14, wherein the foot landing period in the step of calculating the foot landing period is calculated by an equation of foot landing period T=d×

(1/P) where the foot landing period is T, the first maximum value is P, and d is a positive constant.

16. The exercise support method according to claim 12, wherein the step of searching for the first change point and the second change point includes a step of searching for a minimum value equal to or smaller than a predetermined threshold value in the forward direction and the backward direction of the time point of the second maximum value of the composite acceleration signal, and a step of obtaining, when at least one minimum value is found in each of the forward direction and the backward direction of the time point of the second maximum value, a first minimum value of found minimum values which is positioned closest to time progress to the second maximum value in the forward direction of the second maximum value as the first change point, and a second minimum value which is positioned closest to time progress to the second maximum value in the backward direction of the second maximum value as the second change point, and

wherein the step of calculating the foot landing period includes a step of obtaining a period of time between the first minimum value and the second minimum value as the change point interval.

17. The exercise support method according to claim 12, further comprising:

a step of comparing the foot landing period calculated in the step of calculating the foot landing period with a predetermined reference value, generating a notification signal in accordance with a comparison result, and providing the user with predetermined exercise support information based on the notification signal.

18. A non-transitory computer-readable medium having stored thereon an exercise support program that is executable by a computer, the program being executable by the computer to perform functions comprising:

processing for obtaining acceleration signals in three axis directions including a vertical direction, a longitudinal direction, and a lateral direction corresponding to a motion of a body of a user performing exercise of cyclically moving feet;

processing for obtaining a first maximum value within a period of one cycle of a foot movement of the user in an acceleration signal in the vertical direction;

processing for searching for a first change point related to foot landing and takeoff motions of the user in a composite acceleration signal obtained by combining acceleration signals in at least two of the three axis directions, in a forward direction of a time point of a second maximum value of the composite acceleration signal, and a second change point related to foot landing and takeoff motions of the user in the composite acceleration signal, in a backward direction of the time point of the second maximum value, within the period of one cycle; and

processing for obtaining a period of time between the first change point and the second change point as a change point interval, when the first change point and the second change point are detected in the processing for searching for the first change point and the second change point, and calculating a foot landing period of the user while exercising based on the first maximum value of the acceleration signal in the vertical direction and the change point interval.

19. The non-transitory computer-readable storage medium according to claim 18, wherein the foot landing period is calculated based on the first maximum value of the acceleration signal in the vertical direction, when at least one of the first change point and the second change point is not detected in the processing for searching for the first change point and the second change point.

20. The non-transitory computer-readable storage medium according to claim 18, further comprising:

processing for comparing the foot landing period calculated in the processing for calculating the foot landing period with a predetermined reference value, generating a notification signal in accordance with a comparison result, and providing the user with predetermined exercise support information based on the notification signal.