WEARABLE SENSOR DEVICE

Abstract

The present disclosure relates to a wearable sensor device (10) for arrangement to a skin surface of a subject. The wearable sensor device (10) comprises a base structure (1) which, when the wearable sensor device is arranged to a skin surface of a subject, provides a proximal skin facing surface (7) proximal to the skin surface and a distal skin facing surface (8) distal to the skin surface; one or more electrodes (2a, 2b, 2c, 2d) arranged on a proximal skin facing surface (7) of the base structure (1) and configured to provide an electrical signal containing information of the subject; an electronics module (3) configured to process the electrical signal provided by the one or more electrodes (2a, 2b, 2c, 2d), and electrically conductive tracks (2) electrically connecting said one or more electrodes (2a, 2b, 2c, 2d) to the electronics module (3), wherein the electronics module (3) is arranged on the distal skin facing surface of the base structure (1). A method of manufacturing the wearable sensor device (10) is also provided.

Claims

1. A wearable sensor device for arrangement to a skin surface of a subject, comprising a base structure which, when the wearable sensor device is arranged to a skin surface of a subject, provides a first skin facing surface and a second skin facing surface distal to the skin surface wherein the first skin facing surface is located closer to a skin surface than the second skin facing surface when the wearable sensor device is arranged to a skin surface of a subject; one or more electrodes arranged on the first skin facing of the base structure and configured to provide an electrical signal containing information of the subject; an electronics module configured to process the electrical signal provided by the one or more electrodes, and electrically conductive tracks electrically connecting said one or more electrodes to the electronics module, wherein the electronics module is arranged on the second skin facing surface of the base structure, wherein said one or more electrodes and the electronics module are arranged on the same side of the base structure.

2. The wearable sensor device according to claim 1, wherein the first skin facing surface is adapted to extend at least partly along a circumference of the second skin facing surface.

3. The wearable sensor device according to claim 1, wherein the first skin facing surface and the second skin facing surface are at least partly joined by an inclined surface along which said electrically conductive tracks extends between the first skin facing surface and the second skin facing surface.

4. The wearable sensor device according to claim 1, wherein the base structure is made from a flexible material.

5. The wearable sensor device according to claim 1, wherein the base structure comprises two or more first skin facing surface portions, wherein at least one electrode is arranged on each of the two or more first skin facing surface portions.

6. The wearable sensor device according to claim 5, comprising two electrodes arranged on a single first skin facing surface portion.

7. The wearable sensor device according to claim 1, wherein the electrically conductive tracks comprises contact terminals adapted to be in contact with corresponding contact terminals on the electronics module.

8. The wearable sensor device according to claim 7, wherein the electronics module is arranged on the contact terminals of the electrically conductive tracks.

9. The wearable sensor device according to claim 1, wherein the electronics module comprises one or more sensors arranged such that they face the skin surface when the wearable sensor device is arranged thereto.

10. The wearable sensor device according to claim 9, wherein at least one of the one or more sensors is an optical sensor.

11. The wearable sensor device according to claim 1, wherein a top portion of the electronics module is dome shaped.

12. The wearable sensor device according to claim 1, wherein the electronics module comprises a printed circuit board, sensory electronics and a battery.

13. The wearable sensor device according to claim 1, wherein the wearable sensor device is adapted to be fixed to a skin surface by means of an adhesive.

14. A method of manufacturing a wearable sensor device according to claim 1, comprising the steps of providing a base structure, arranging electrically conductive tracks such that they extend from the electrodes to a distal second skin facing surface, arranging one or more electrodes on a first skin facing surface of the base structure, wherein the first skin facing surface is located closer to a skin surface than the second skin facing surface when the wearable sensor device is arranged to a subject's skin, providing an electronics module comprising one or more contact terminals, and arranging the electronics module to the base structure such that the one or more contact terminals on the electronics module are in contact with one or more contact terminals of the electrically conductive tracks, wherein said one or more electrodes and the electronics module are arranged on the same side of the base structure.

15. A method of measuring a bio-impedance signal of a subject comprising applying the wearable sensor device according to claim 1 to a skin surface of a subject, and measuring a bio-impedance signal of the subject via the wearable sensor device.

16. The wearable sensor device according to claim 2, wherein the first skin facing surface is adapted to extend along the circumference of the second skin facing surface in an amount of from 50% to 100%.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The invention will in the following be described in more detail with reference to the enclosed drawings, wherein:

[0050] FIG. 1a illustrates a schematic view of a wearable sensor device according to a prior art solution;

[0051] FIG. 1b illustrates a schematic view of a wearable sensor device according to a prior art solution;

[0052] FIG. 2 illustrates a perspective view of a wearable sensor device according to an embodiment of the present invention;

[0053] FIG. 3a illustrates an exploded view of a wearable sensor device according to an embodiment of the present invention, as seen from below;

[0054] FIG. 3b illustrates an exploded view of a wearable sensor device according to an embodiment of the present invention, as seen from above;

[0055] FIG. 4a illustrates a schematic view of a wearable sensor device according to an embodiment of the present invention;

[0056] FIG. 4b illustrates a schematic view of a wearable sensor device according to an embodiment of the present invention;

[0057] FIG. 5 illustrates a flow chart of a method according to an embodiment of the present invention.

DESCRIPTION OF EMBODIMENTS

[0058] The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, like numbers refer to like elements.

[0059] In the prior art, the conventional way of connecting electrodes 2a′, 2b′ in a wearable sensor device 10′ to an electronics module 3′ is to pull the electrically conductive tracks 2′ through a base structure 1′ of the wearable sensor device 10′ as shown in FIG. 1a and FIG. 1b. In both cases, the electrically conductive tracks 2′ are twisted into the base structure 1′, and then twisted so that they align with the top surface of the base structure 1′ before being connected to the electronics module 3′. In the first case, as depicted in FIG. 1a, the electrically conductive tracks 2′ are twisted about 180 degrees in order to align with the top surface of the base structure 1′. In the second case, as depicted in FIG. 1b, the electrically conductive tracks are twisted 90 degrees into the base structure 1′ and then twisted 90 degrees into a tangential direction of the top surface of the base structure 1′. Due to this significant twisting of the electrically conductive tracks, an increased mechanical stress is introduced in the twisted parts of the electrically conductive tracks. Also, the electrically conductive tracks 2′ are elongated which increases the electrode path, which consequently increases the risk of a loss in signal quality.

[0060] FIG. 2 illustrates a perspective view of a wearable sensor device 10 according to an embodiment of the present invention. According to one embodiment, the wearable sensor device 10 comprises a base structure 1 which, when the wearable sensor device 10 is arranged to a skin surface 100 of a subject, provides a proximal skin facing surface 7 proximal to the skin surface 100 and a distal skin facing surface 8 distal to the skin surface 100. More specifically, the base structure 1 comprises a flat and elongated shape, wherein the two ends of the base structure provide a first and second proximal skin facing surfaces 7a, 7b. Together, they constitute a portion of the proximal skin facing surface 7. The first and the second proximal skin facing portions 7a, 7b are arranged on opposite sides of the distal skin facing surface 8. The remainder of the proximal skin facing surface 7 is constituted by two skin facing side surfaces which connect the first and the second proximal skin facing portions 7a, 7b along opposite sides of the distal skin facing surface 8.

[0061] On each proximal skin facing surface portion 7a, 7b, two electrodes are arranged. On the first skin facing surface portion 7a, a first and a second electrode 2a, 2b is located. On the second skin facing surface portion 7b, a third and a fourth electrode 2c, 2d is located. The electrodes 2a, 2b, 2c, 2d are configured to, when in use, provide an electrical signal containing information of the subject. Moreover, the wearable sensor device 10 comprises an electronics module 3 arranged on the distal skin facing surface 8, which is configured to process the electrical signal provided by the electrodes 2a, 2b, 2c, 2d. The first electrode 2a, the second electrode 2b, the third electrode 2c, and the fourth electrode 2d are electrically connected to the electronics module 3 by means of separate electrically conductive tracks 2. The electrically conductive tracks 2 are separated from each other.

[0062] The base structure 1 has the function of providing a bottom surface onto which the electrodes, the conductive tracks and the electronics module can be fixated. When correctly arranged on a skin surface 100 of a subject, the electronics module 3 is arranged in-between the subject's skin surface 100 and the base structure 1. Hence, the electrically conductive tracks 2 do not need to be twisted through the base structure in order to be electrically connected to the electronics module 3. Rather, the electrically conductive tracks 2 merely extend along the proximal skin facing surface 7 and the distal skin facing surface 8, thereby reducing the mechanical stress of the electrically conductive tracks 2 during use.

[0063] Moreover, since the electronics module 3 is arranged on the same side of the base structure 1 as the electrically conductive tracks 2, it is possible to have a direct interconnect system between these two elements without having to significantly twist the electrode tracks 2. The relative positioning of the electronics module is such that next to the collection of physiological data from the electrodes, physiological data can also be collected directly from the user's tissue at the skin surface by sensors 4 arranged on the bottom surface of the electronics module 3. The sensors 4 may for instance be optical sensors or temperature sensors.

[0064] The wearable sensor device 10 of the present invention enables all components, i.e. the electrodes 2a, 2b, 2c, 2d, the electrically conductive tracks 2, the electronics module 3, to be held in a secured position and simultaneously achieve smaller distances and less curvatures in the path of the electrical signals. This enables to possibility of obtaining reliable signals of e.g. bio-potential while improving on usability as compared to existing solutions.

[0065] FIGS. 3a and 3b illustrate an exploded view of a wearable sensor device according to an embodiment of the present invention, as seen from above and below, respectively. Each of the four electrically conductive tracks 2 comprises a contact terminal 5 which is configured to electrically connect to a corresponding contact terminal 6 arranged on a top surface of the electronics module 3. The contact terminals 5 of the electrically conductive tracks 2 are arranged in a grid formation, and merely separated a small distance from each other. Moreover, the electrically conductive tracks 2 extend out from the contact terminals 5 first in a lateral direction and then extend in a longitudinal direction out of the distal skin facing surface 8.

[0066] In one embodiment, the electrically conductive tracks 2 are covered by a dielectric material 9, see FIGS. 4a, 4b. The dielectric material may be provided as a layer covering the electrically conductive tracks 2 on both the proximal skin facing surface 7 and the distal skin facing surface 8. The dielectric layer may cover the entire or a major part of the bottom surface of the base structure 1 except the electrodes 2a, 2b, 2c, 2d and the contact terminals 5, i.e. the entire or a major part of the proximal skin facing surface 7 and the distal skin facing surface 8. It may specifically cover the electrically conductive tracks 2. The dielectric material 9 may cover the electrically conductive tracks 2 while not covering large portions of the skin facing surface 7 and/or the distal skin facing surface 8.

[0067] FIGS. 4a and 4b illustrate schematic views of a wearable sensor device according to an embodiment of the present invention. In FIG. 4a, the wearable sensor device 10 is depicted in a mounting shape but displaced from the skin surface 100 of a subject. The base structure 1, having a flexible material, bends around the electronics module 3, which in this particular embodiment has a cuboid shape. The contact terminals 5 of the electrically conductive tracks 2 are electrically connected to the contact terminals 6 located on the top surface of the electronics module 3. On each side of the electronics module 3, the electrically conductive tracks 2 curves in accordance with the curvature of the flexible base structure 1. As can be seen in FIG. 4a, there is a gap between longitudinal sides of the electronics module 3 and the base structure 1.

[0068] In FIG. 4b, the wearable sensor device 10 is also depicted in a mounting shape but displaced from the skin surface 100 of a subject. However, contrary to the wearable sensor device 10 depicted in FIG. 4a, the wearable sensor device 10 depicted in FIG. 4b comprises a dome-shaped electronics module 3 with a flat top surface. As can be seen in FIG. 4b, the gap between longitudinal sides of the electronics module 3 and the base structure 1 has been significantly reduced.

[0069] Moreover, as can be seen in FIGS. 4a and 4b, the electronics module 3 comprises sensors located on its bottom side. These may be brought into direct contact with the skin surface of a subject when the wearable sensor device is arranged thereto. Thus, sensors 4 which require direct contact or at least unobstructed line of sight may be incorporated into the wearable sensor device. For instance, such sensors may be optical sensors or temperature sensors.

[0070] FIG. 5 illustrates a flow chart of a method M100 according to an embodiment of the present invention. The method M100 comprises the steps of: providing M101 a base structure 1; arranging M102 electrically conductive tracks 2 such that they extend from the electrodes 2a, 2b, 2c, 2d to a distal skin facing surface 8; arranging M103 one or more electrodes 2a, 2b, 2c, 2d on a proximal skin facing surface 7 of the base structure 1; providing M104 an electronics module 3 comprising one or more contacts 6; and arranging M105 the electronics module to the base structure 1 such that the one or more contact terminals 6 on the electronics module 3 are in contact with the one or more contact terminals 5 of the electrically conductive tracks.

[0071] By this, a simplification in production process regarding the establishment of an interconnection between the electronics module and the conductive tracks is established, since no additional features need to be added for the electrical signal to reach the electronics module through the base structure 1.

[0072] In the drawings and specification, there have been disclosed preferred embodiments and examples of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for the purpose of limitation, and may be combined in various ways unless being clearly incompatible with one another. However, the scope of the invention is set forth in the following claims.