Wearable activity monitoring device and related method

• US 20160007888A1
• Filed: 07/15/2014
• Published: 01/14/2016
• Est. Priority Date: 07/11/2014
• Status: Active Application

• Current Assignee: Suunto Oy (Anta International Group Holdings Ltd.)
• Original Assignee: Suunto Oy (Anta International Group Holdings Ltd.)
• Inventors: Nieminen, Heikki, Martikka, Mikko, Kemetter, Markus, Miettinen, Michael, Lindman, Erik
• Application Number:
  US14/331,268
• Publication Number:
  US 20160007888A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 5/0022 Monitoring a patient using a global network, e.g. telephone networks, internet
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A61B 5/112 Gait analysis
• CPC Class Codes: A61B 5/1123 Discriminating type of movement, e.g. walking or running A61B5/1116, A61B5/112 take precedence
• CPC Class Codes: A61B 5/681 Wristwatch-type devices
• CPC Class Codes: A61B 5/7246 using correlation, e.g. template matching or determination of similarity

Abstract

The invention relates to a device and method for monitoring physical activity of a person. The device comprises an acceleration sensor for providing acceleration data corresponding to movements of the person, a memory unit capable of storing an activity index value describing cumulative physical activity of the person, and data processing unit capable of being operated in at least a first activity monitoring mode in which the data processing unit is adapted to update the activity index value based on the acceleration data. In addition, the processing unit is, in the first activity monitoring mode, configured to determine if, and to update the activity index value only if, the acceleration data corresponds to walking- and/or running-related movements of the person. The invention allows for robust monitoring of activities that have an impact on fitness and health of individuals and reduce the risk of incorrect activity recordings.

Claims

1. A device for monitoring physical activity of a person, comprising

an acceleration sensor for providing acceleration data corresponding to movements of the person,

a memory unit capable of storing an activity index value describing a cumulative physical activity of the person, and

data processing unit capable of being operated in at least a first activity monitoring mode in which the data processing unit is adapted to update said activity index value based on said acceleration data,

wherein in said first activity monitoring mode the processing unit is configured to determine if, and to update the activity index value only if, the acceleration data corresponds to walking- and/or running-related movements of the person.

2. The device according to claim 1, wherein the processing unit is configured to determine if the acceleration data corresponds to walking- and/or running-related movements of the person by analyzing the periodicity of the acceleration data.

3. The device according to claim 1, wherein the processing unit is configured to determine if the acceleration data corresponds to walking- and/or running-related movements of the person by analyzing the average magnitude of the acceleration data.

4. The device according to claim 1, wherein in said first activity monitoring mode, the data processing unit in configured to

detect periodic motions from the acceleration data,

determine frequency of the periodic motions,

determine whether the frequency of the periodic motions is at a predefined frequency range, and

update the activity index value using said frequency of periodic motions only if the frequency of the periodic motions is at said predefined frequency range.

5. The device according to claim 1, wherein in said first activity monitoring mode, the data processing unit is configured to

determine average acceleration based on the acceleration data,

determine whether the average acceleration is within a predefined acceleration range, and

update the activity index using said average acceleration only if the average acceleration is within said predefined acceleration range.

6. The device according claim 1, wherein in said first activity monitoring mode the processing unit is configured to

determine average acceleration based on the acceleration data,

convert the average acceleration determined to average speed of the person using a conversion function stored in the memory of the device, and

use the average speed for updating the activity index value.

7. The device according to claim 6, further comprising means for receiving speed data of the person from a speed sensor and to adapt properties of the conversion function in the memory of the device so as to reflect the correct dependence between the average acceleration and said speed data.

8. The device according to claim 1, wherein the processing unit is additionally configured to use at least one of the following parameters storable in the memory of the device for updating the activity index value:

age of the person, sex of the person, mass of the person, fitness index of the person, maximum oxygen intake value (VO_2,max) of the person.

9. The device according to claim 1, wherein the processing unit is capable of being operated in at least one second activity monitoring mode in which the processing unit is configured to update the activity index value using different update criteria.

10. The device according to claim 9, further comprising user interface means for allowing the person to switch between the first and second activity monitoring modes of the data processing unit.

11. The device according to claim 1, wherein it comprises means for mounting the device on the wrist of the person.

12. The device according to claim 1, further comprising at least one other sensor than the acceleration sensor or means for wirelessly receiving data form such other sensor, and the data processing unit being adapted to operate, in response to user action through user interface means of the device, in a second activity monitoring mode utilizing data form said other sensor for monitoring the activity of the person.

13. The device according to claim 1, wherein in said first activity monitoring mode the processing unit is configured

to determine whether said acceleration data exceeds a predefined magnitude threshold,

only if said acceleration data exceeds said predefined magnitude threshold, to determine whether the acceleration data corresponds to walking-related movements of the person, and

if the acceleration data corresponds to said walking-related movements of the person, to update the activity index value based on the acceleration data.

14. The device according to claim 13, wherein in said first activity monitoring mode the processing unit is further configured

if the acceleration data does not correspond to said walking-related movements of the person, to determine if the acceleration data corresponds to running-related movements of the person, and

if the acceleration data corresponds to said running-related movements of the person, to update the activity index value based on the acceleration data.

15. A device for monitoring physical activity of a person, comprising

an acceleration sensor for providing acceleration data corresponding to movements of the person,

a memory unit capable of storing an activity index value describing a cumulative physical activity of the person, and

a data processing unit adapted to update said activity index value based on said acceleration data according to update criteria,

wherein

the data processing unit is capable of being operated in at least a first activity monitoring mode and a second activity monitoring mode, and

the data processing unit is configured to use different update criteria in said first activity monitoring mode than in said second activity monitoring mode.

16. A device for monitoring physical activity of a person, comprising

an acceleration sensor for providing acceleration data corresponding to movements of the person, and

a data processing unit for analyzing the acceleration data for computing an activity index describing a cumulative activity of the person, the data processing unit comprising means for detecting periodic motions from the acceleration data, means for determining frequency of the periodic motions, and means for determining whether the frequency of the periodic motions is within a predefined frequency range,

wherein said data processing unit further comprises

means for determining average acceleration based on the acceleration data,

means for determining whether the average acceleration is within a predefined acceleration range, and

means for updating the activity index using said frequency of periodic motions and average acceleration if the frequency of the periodic motions and the average acceleration are within said predefined ranges.

17. A method for monitoring physical activity of a person in a wearable device, comprising

providing acceleration data corresponding to wrist movements of the person, and

analyzing the acceleration data unit in a first activity monitoring mode of the wearable device in order to derive an activity index corresponding to the intensity of the physical activity,

wherein the acceleration data is analyzed in said first activity monitoring by detecting features of the acceleration data that correspond to cadence of walking and/or running, and if such features are found, updating the activity index using said features.

18. The method according to claim 17, wherein said features comprise periodic acceleration peaks in the acceleration data being repeated at a predefined frequency range, and/or total average acceleration determined from the acceleration data over a predefined time period at a predefined acceleration range.