WO2022137041A1

WO2022137041A1 - Wearable device for effecting an audio communication via bone conduction and for detecting vital signals, and system and method thereof

Info

Publication number: WO2022137041A1
Application number: PCT/IB2021/061848
Authority: WO
Inventors: Edoardo PARINI; Alberto PIEROTTI
Original assignee: Deed S.R.L.
Priority date: 2020-12-24
Filing date: 2021-12-16
Publication date: 2022-06-30
Also published as: IT202000032465A1

Abstract

Described herein is a wearable device (10) for effecting an audio communication via bone conduction and for detecting vital signals of an individual, comprising: means, in particular a communication unit (23), adapted to receive as input an audio signal (26); a control unit (21), in particular a microprocessor; an audio I/O unit (27), adapted to convert an audio signal into an electric signal, and vice versa; at least one transducer (29,31) arranged on an inner surface (13) of said device and adapted to generate a vibration corresponding to said input audio signal (26), wherein said at least one transducer (29,31) is surrounded by a layer of electrically conductive and sound-absorbent material, and constitutes a first electrode adapted to detect a first vital signal of said individual.

Description

WEARABLE DEVICE FOR EFFECTING AN AUDIO COMMUNICATION VIA BONE CONDUCTION AND FOR DETECTING VITAL SIGNALS, AND SYSTEM AND METHOD THEREOF

DESCRIPTION

The present invention relates to a wearable device for effecting an audio communication via bone conduction and for detecting vital signals, as well as to a system and a method associated therewith.

More in particular, the vital signals detected by the wearable device are intended to be processed in order to provide an electrocardiogram of the individual wearing said device. A wearable device is known from United States patent US 9,706,037 B2 which allows a user to effect an audio communication via bone conduction.

The wearable device of said United States patent comprises a transducer adapted to generate a vibration from an audio signal received via an audio communication system, e.g. a mobile phone.

As shown in Figure 1, a user of a wearable device 1, in particular a wristband, puts a finger 4 in proximity to an ear 5 so that the vibration 7 is conducted from the wearable device 1 directly to the inner ear of the ear 5, thus avoiding to involve the outer ear of the ear 5, in particular the tympanum.

Wearable devices are also known in the art, in particular smartwatches, which, in association with an app that can be installed in a smartphone, allow recording an individual’s electrocardiogram. One example of such smartwatches is the Apple Watch. As shown on Apple’s website https://support.apple.com/en-us/HT204666, the Apple Watch Series 4, Series 5 and Series 6 devices have electrodes incorporated into the crown and the back, which can, in combination with the associated app, measure the electric signals of the heart.

When the user places a finger on the crown of the watch, a closed circuit is created between the heart and both arms, capturing the cardiac electric signals.

Therefore, smartwatches have backs that are increasingly crowded with sensors. In addition, the watch crown must be so constructed that it can be used as an electrode.

This is in contrast with market requirements calling for wearable devices that are smaller and more comfortable to wear.

Moreover, in order to correctly detect the vital signals of the individual who is wearing the wearable device, it is necessary that the points of epidermal contact between the device and the individual are as little invasive as possible, for the purpose of achieving high levels of comfort, design and ergonomics of the device while ensuring that vital signals are read correctly.

Furthermore, designers also need to properly utilize the limited room available so as to be able to add further sensors for additional functions that will certainly be implemented in the near future.

It is therefore one object of the present invention to provide a wearable device for effecting an audio communication via bone conduction and for detecting vital signals, as well as a system and a method associated therewith, wherein the various components are arranged in such a way as to reduce the overall dimensions of the device.

It is another object of the present invention to provide a wearable device for effecting an audio communication via bone conduction and for detecting vital signals, as well as a system and a method associated therewith, wherein the distribution of the various components is optimized so as to allow other sensors and functions to be added to the device in the future.

It is a further object of the present invention to provide a wearable device for effecting an audio communication via bone conduction and for detecting vital signals, as well as a system and a method associated therewith, which are minimally invasive and provide high levels of comfort and ergonomics while ensuring that vital signals are read correctly. In brief, the present invention envisages that the wearable device comprises at least one transducer generating a vibration, said transducer being surrounded by a layer of electrically conductive and sound-absorbent material, so as to constitute a first electrode. It is known that two electrodes are sufficient to obtain vital signals suitable for recording an electrocardiogram (see, for example, the article by Hsin-Yen Hsieh et al. entitled “Two-electrode-pair electrocardiogram with no common ground between two pairs”, htt s : // ai . sci tati on. org/doi/ 10.1063/1.5016939).

A traditional second electrode can therefore be applied to the user’s skin, e.g. to a hand not wearing the device according to the invention, or to another body part, or anyway in a position easily accessible to the user, who must then be able to touch the second electrode with a body part other than the one whereupon the first electrode is acting, e.g. with a hand not wearing the device.

When one wants to use three electrodes to obtain the electrocardiogram, the wearable device according to the invention may comprise a second electrode made in a traditional manner. Alternatively, the second electrode may be implemented as a second transducer generating a vibration, said second transducer being also surrounded by a layer of electrically conductive and sound-absorbent material. As a further alternative, the second electrode may be provided as a layer of electrically conductive and sound-absorbent material. A third electrode may be applied to the user’s skin, e.g. to a hand not wearing the device according to the invention, or to another body part, or anyway in a position easily accessible to the user, who must then be able to touch the third electrode with a body part other than the one whereupon the first electrode is acting, e.g. with a hand not wearing the device.

The layer of electrically conductive and sound-absorbent material that surrounds the transducer may be provided as a component integrated with the associated transducer or may be buried in the material of the wearable device.

The quality of the audio communication increases when two or more transducers surrounded by a region of electrically conductive and sound-absorbent material are used. The sound-absorbent material is also useful to provide better audio communication quality, in that it eliminates mechanical vibrations and increases microphone directionality. In addition, it reduces the outward sound leakage resulting from the necessity of raising the volume of the audio communication, and hence the intensity of the vibration emitted by the transducer, because of the absorption of the signal by the skin and the underlying fatty tissues.

The transducers are strategically positioned close to each other on the wearable device and are very small.

The arrangement of the transducers follows the ergonomics of the bone structure whereon the device is worn.

In an embodiment of the present invention, the wearable device for effecting an audio communication via bone conduction and for detecting vital signals of an individual comprises: means, in particular a communication unit, adapted to receive as input an audio signal; a control unit, in particular a microprocessor; an audio I/O unit, adapted to convert an audio signal into an electric signal, and vice versa; a transducer arranged on an inner surface of said device and adapted to generate a vibration corresponding to the input audio signal, wherein the transducer is surrounded by a layer of electrically conductive and sound-absorbent material, and constitutes a first electrode adapted to detect a first vital signal of the individual.

In a further embodiment of the wearable device, the inner surface of the wearable device comprises at least a second electrode adapted to detect a second vital signal of the individual.

In a further embodiment of the wearable device, the second electrode comprises a second transducer surrounded by a layer of electrically conductive and sound-absorbent material. In a further embodiment of the wearable device, the second electrode comprises at least one region of the inner surface of the wearable device comprising a layer of electrically conductive and sound-absorbent material.

In a further embodiment of the wearable device, the layer of electrically conductive and sound-absorbent material emerges, at least partly, in and from a region of the inner surface.

In a further embodiment of the wearable device, the layer of electrically conductive and sound-absorbent material comprises one of the following materials: conductive rubber; conductive fabric; conductive foam; conductive sponge.

In a further embodiment of the wearable device, the layer of electrically conductive and sound-absorbent material may be shaped as a closed container internally housing the transducer.

In a further embodiment of the wearable device, the layer of electrically conductive and sound-absorbent material is buried in the structure of the material constituting the inner surface of the device.

In a further embodiment of the wearable device, the transducer comprises a coil equipped with a magnetic element, and wherein a first conducting element adapted to transport an audio communication signal, a second conducting element adapted to be connected to the ground of said transducer and a third conducting element connected to the layer of electrically conductive and sound-absorbent material extend from said transducer.

In a further embodiment of the wearable device, the audio I/O unit comprises a microphone adapted to receive an audio signal from the outside environment and a loudspeaker for outputting an audio signal into the outside environment.

In a further embodiment of the wearable device, the device comprises a power supply unit, in particular a battery.

In a further embodiment of the wearable device, the device comprises a flexible printed circuit comprising at least the control unit, the communication unit and the power supply unit.

In a further embodiment of the wearable device, the device comprises longitudinal coupling means adapted to allow an individual to wear the device.

In a further embodiment of the invention, the wearable device is one of the following items: watch strap; wristband; armlet; bracelet; ring; neckband; necklace; hairband; earflap; headband; cap; helmet; garment; t-shirt; military jacket; sports jacket; tracksuit; jersey; jacket; chest belt; trousers; glove; glasses; dummy; gum shield; or the wearable device can be electrically connected to a repositionable remote electrode.

In a further embodiment of the invention, a system is envisaged which comprises a wearable device and an external device, wherein the wearable device is adapted to transmit an audio signal and signals processed by the control unit and representative of vital signals of an individual to the external device according to a predetermined communication method, said communication method comprising: Wi-Fi; Bluetooth; a global positioning system; a cellular communication; a code-division multiplex access; a universal mobile telecommunications system; a wireless broadband; a global system for mobile communications; a wireless communication, including a near-field communication; a wired communication method; a high-definition multimedia interface; a standard interface; a fixed telephone network.

In a further embodiment of the invention, the external device comprises a mobile device, a smartphone, a tablet PC, a server or further wearable devices, the external device being equipped with a display for displaying an electrocardiogram of an individual.

In a further embodiment of the present invention, a method is envisaged for effecting an audio communication via bone conduction and for detecting vital signals of an individual by means of a wearable device, comprising the steps of: receiving as input an audio signal via communication means of the device, in particular a communication unit; converting an audio signal into an electric signal, and vice versa, through an audio I/O unit of the device; generating a vibration corresponding to the input audio signal by means of a transducer arranged on an inner surface of the device, the transducer being controlled by a control unit of the device, wherein it is envisaged to surround said transducer with a layer of electrically conductive and sound-absorbent material, so as to constitute a first electrode adapted to detect a first vital signal of the individual.

In a further embodiment of the method according to the present invention, it is envisaged to provide the inner surface of the wearable device with at least a second electrode adapted to detect a second vital signal of the individual.

In a further embodiment of the method according to the present invention, it is envisaged to realize the second electrode as a second transducer surrounded by a layer of electrically conductive and sound-absorbent material.

In a further embodiment of the method according to the present invention, the second electrode is formed in at least one region of the inner surface of the wearable device comprising a layer of electrically conductive and sound-absorbent material.

In a further embodiment of the method according to the present invention, it is envisaged to form said layer of electrically conductive and sound-absorbent material in such a way that a region thereof emerges, at least partly, from the inner surface.

In a further embodiment of the method according to the present invention, the layer of electrically conductive and sound-absorbent material is made of one of the following materials: conductive rubber; conductive fabric; conductive foam; conductive sponge.

In a further embodiment of the method according to the present invention, the layer of electrically conductive and sound-absorbent material is shaped as a closed container internally housing the transducer.

In a further embodiment of the method according to the present invention, the layer of electrically conductive and sound-absorbent material is buried in the structure of the material constituting said inner surface, in particular by welding, screwing or gluing. Further advantageous features of the present invention will be set out in the appended claims.

Such further features and advantages of the present invention will become more apparent in light of the following description of an embodiment thereof as shown in the annexed drawings, provided merely by way of non-limiting example, wherein:

- Figure 1 shows a prior-art wearable device utilizing bone conduction as a means to effect an audio communication;

- Figures 2 and 3 show a wearable device according to the present invention in unworn and worn positions, respectively;

- Figure 4 shows a block diagram of components of a first embodiment of the wearable device of Figures 2 and 3;

- Figures 4a and 4b show two different arrangements of electrodes on the wearable device of Figures 2 and 3;

- Figure 5 shows the positions of the electrodes in the arrangement of Figure 4b, when the wearable device 10 is associated with a user’s wrist;

- Figure 6a shows a sectional view of a transducer of the device of Figures 2 and 3, said transducer being surrounded by a layer of electrically conductive and sound-absorbent material;

- Figure 6b shows an embodiment of the device of Figures 2 and 3 comprising two transducers;

- Figure 7 shows a flow chart of a method used for effecting an audio communication via bone conduction and for detecting vital signals according to the present invention;

- Figures 8a-8h and 9a-9h show items made in accordance with the teachings of the present invention.

With reference to Figures 2 and 3, there is shown a wearable device 10 according to the invention, in particular a wristband, in an unworn position (Figure 2) and in a worn position (Figure 3).

The wearable device 10 comprises an outer surface 13 and an inner surface 14, which is adapted to remain in contact with the skin of a individual wearing the wearable device 10.

The wearable device 10 can be put on or removed from the user’s skin by means of coupling means that are well-known in the jewel and watch making fields. For example, the wearable device 10 may include longitudinal coupling means 15,17 at the two ends, respectively, of the wearable device 10, which are then coupled together. As an alternative or in addition, such coupling means may comprise magnets or magnetic materials.

The wearable device 10 may be made of materials such as metal, fabric, leather, rubber, synthetic fibre, wood, ceramic or plastic. It may also include layers of a plurality of such materials, forming a multilayer structure.

As will be illustrated in detail hereinafter, the wearable device 10 comprises at least one transducer 29,31 suitably arranged on the inner surface 14 of the wearable device and adapted to generate a vibration corresponding to an audio signal inputted to the wearable device 10.

With reference to Figure 4, there is shown a block diagram of components of the wearable device 10.

The wearable device 10 comprises a control unit 21, a communication unit 23, a power supply unit 25, an audio I/O (Input/Output) unit 27, at least one transducer 29, 31 and a memory 33.

The control unit 21, in particular a microprocessor, can recognize information about the respective components arranged within the wearable device 10 and can generally control the respective components according to the recognized information.

The communication unit 23 is adapted to receive a first signal 26, typically representative of a voice signal in the form of digital data packets, from an external device (not shown) via a predetermined communication method, and to send to the control unit 21 a second signal 22 after having decoded and reconstructed it.

The communication unit 23 is also adapted to receive a signal received by the I/O unit 27 and to send it to the external device after having encoded and packetized it.

The external device may be a mobile device, such as a smartphone, a tablet PC, a server or other wearable devices equipped with a display.

The predetermined communication method may include: Wi-Fi; Bluetooth; a global positioning system, e.g. GPS; a cellular communication, including Long Term Evolution (LTE), LTE Advanced (LTE-A), 5G or 6G; a code-division multiplex access, e.g. CDMA or wideband CDMA (WDCMA); a universal mobile telecommunications system (UMTS); a wireless broadband; a global system for mobile communications, e.g. GSM; a wireless communication, including near-field communication (NFC).

The wearable device 10 may also receive the first signal 26 via a wired communication method, including a universal serial bus (USB); a high-definition multimedia interface (HDMI); a standard interface, e.g. RS-232; a fixed telephone network. As a consequence, the communication unit 23 may include at least one of a cellular module, a Wi-Fi module, a Bluetooth module, a GPS module, an NFC module and a radio-frequency (RF) module. The power supply unit 25 can handle the power supplied to the wearable device 10 under the supervision of the control unit 21.

The power supply unit 25 may include either a power management integrated circuit (PMIC) or a battery.

The power supply unit 25 may receive power via a wireless charging method, energy harvesting techniques or a wired charging method.

The wireless charging method may be a magnetic resonance method or a method based on magnetic induction or electromagnetic waves.

In addition, the battery can store or generate energy and supply energy to the wearable device 10. The battery may be a rechargeable battery or a solar battery.

The audio I/O unit 27 is adapted to convert the second signal 22 received from the communication unit 23 into an electric signal. Alternatively, the audio I/O unit 27 may convert an electric signal into a sound that can be emitted into the outside environment. In other words, the audio I/O unit 27 can convert the sound and the electric signal in a bidirectional manner.

The audio I/O unit 27 may comprise a microphone for receiving an audio signal from the outside environment and a loudspeaker for outputting an audio signal into the outside environment.

In the description of the present invention, the audio I/O unit 27 is shown as a single module. The microphone for receiving the sound from the outside environment and the loudspeaker for emitting the sound into the outside environment may however be arranged separately in the wearable device 10.

The control unit 21, the communication unit 23 and the power supply unit 25 may be incorporated into a flexible printed circuit 50 (see Figure 6b) of the wearable device 10. Therefore, when viewing the wearable device 10 from the outside, the audio I/O unit 27 may be visible, whereas the control unit 21, the communication unit 23 and the power supply unit 25 are not.

The audio I/O unit 27 may be exposed to the inner surface 14 of the wearable device to output a sound into the outside environment or to receive a sound from the outside environment, but may also be positioned within the flexible printed circuit 50.

The memory unit 33 can store data received or generated by the control unit 21 or other components.

The memory unit 33 may be a memory integrated into the control unit. In more detail, the memory unit 33 may include at least one of: a volatile memory, e.g. a dynamic random access memory (DRAM); a static RAM (SRAM) or a synchronous dynamic RAM (SDRAM); a non-volatile memory, e.g. a one-time programmable read-only memory (OTPROM); a programmable ROM (PROM); an erasable and programmable ROM (EPROM); an electrically erasable and programmable ROM (EEPROM); a mask ROM; a flash ROM; a NAND flash memory; a NOR flash memory.

The memory unit 33 may be an external memory. More in detail, the memory unit 33 may further comprise a flash unit, e.g. a compact flash (CF), secure digital (SD), micro secure digital (micro-SD), mini secure digital (mini-SD) or extreme digital (xD) unit, a memory stick, and/or the like. In this case, the memory unit 33 may be connected to the wearable device 10 through various interfaces.

The at least one transducer 29,31 is adapted to receive a third signal 24 from the control unit 21 and to generate a corresponding vibration.

The control unit 21 comprises an audio amplifier, preferably a multichannel one, which is adapted to amplify the second signal 22 received from the external device and to generate the third signal 24 that is inputted to the at least one transducer 29,31.

The user can put a finger against his/her ear, in particular against the cartilage thereof, and hear the sound corresponding to the first signal 26 received from the outside environment, corresponding to the third signal 24.

In this first embodiment, at least one transducer 29,31 is positioned on the inner surface 14 of the wearable device 10 in various possible arrangements, some examples of which are shown in Figures 4a and 4b.

The Applicant of the present patent application has been able to incorporate into the wearable device 10 transducers 29,31 having a volume approximately 7 times smaller than prior-art transducers.

This also results in more compact and aesthetically pleasant wearable devices 10, which can advantageously be adapted to different bone conformations in terms of wrist size and bone structure.

The device 10 according to the present invention can then be worn continuously, because its weight is evenly distributed along the bone structure involved, e.g. the wrist, thus creating no discomfort for the user.

Figure 5a illustrates the position of the at least one transducer 29,31 when the wearable device 10 is associated with a user’s wrist, in the arrangement corresponding to Figure 4a.

With reference to Figure 6a, there is shown a transducer 29 surrounded by a layer 32 of electrically conductive and sound-absorbent material.

The layer 32 emerges, at least partly, in a region 32a from the inner surface 14 of the wearable device 10.

The electrically conductive and sound-absorbent material may be, for example, one of the following materials: conductive rubber; conductive fabric; conductive foam; conductive sponge.

The layer 32 of electrically conductive and sound-absorbent material may be shaped as a closed container internally housing the transducer 29, i.e. as an integrated component, or may be buried in the structure of the material constituting the inner surface 14 of the wearable device 10, e.g. by welding, screwing or gluing.

The transducer 29 comprises a coil 40 equipped with a magnetic element, preferably arranged in a central position. A first conducting element 42, which transports the audio signal, and a second conducting element 44, connected to ground, extend from the transducer 29. A third conducting element 56 is connected to the layer 32 of electrically conductive and sound-absorbent material, and transports a vital signal of the individual. In particular, the first, second and third conducting elements 42,44,56 are conductor wires.

Since at least two electrodes are necessary in order to record an electrocardiogram, a traditional second electrode can be applied to the user’s skin, e.g. to a hand not wearing the device according to the invention, or to another body part, or anyway in a position easily accessible to the user, who must then be able to touch the second electrode with a body part other than the one whereupon the first electrode is acting, e.g. with a hand not wearing the device.

When one wants to use three electrodes to obtain the electrocardiogram, the wearable device 10 may comprise a second electrode made in a traditional manner. Alternatively, the second electrode may be implemented as a second transducer 31 generating a vibration, said second transducer 31 being also surrounded by a layer of electrically conductive and sound-absorbent material. As a further alternative, the second electrode may be provided as a layer of electrically conductive and sound-absorbent material. A third electrode may then be applied to the user’s skin, e.g. to a hand not wearing the device according to the invention, or to another body part, or anyway in a position easily accessible to the user, who must then be able to touch the third electrode with a body part other than the one whereupon the first electrode is acting, e.g. with a hand not wearing the device.

The vital signals transported by the third conducting element 56 and by the at least one second electrode are supplied to the control unit 21, which is adapted to process them in a per se known manner and to transmit appropriate instructions to the external device for displaying on the latter’s display the electrocardiogram of the individual who is wearing the device 10.

In a further embodiment of the invention, one or more regions 45,46 of the inner surface 14 of the device 10 comprise a transducer 31 realized in the same way as the transducer 29 shown in Figure 6a.

With reference to Figure 6b, which corresponds to the embodiment of Figure 4a, there is shown an illustrative embodiment of the invention comprising two transducers 29,31 that transmit a respective vibration to a bone structure 53, e.g. a wrist, of the user wearing the device 10.

In the case of a single transducer, as in the example of Figure 4b, it transports the communication audio signal.

When two or more transducers 29,31 are present, as in the illustrative embodiment shown in Figures 4a and 6b, they are surrounded by a respective layer 32,32’ of electrically conductive and sound-absorbent material. The regions 32, 32’ are electrically insulated and constitute two electrodes.

When two or more transducers 29,31 are present, the control unit 21 is adapted to select that transducer 29,31, among those included in the device 10, which ensures the best transmission by bone conduction. This selection is made by the control unit 21 by measuring the transducers’ output signals and by selecting the strongest one.

With reference to Figure 7, there is shown a flow chart 100 of a method for effecting an audio communication via bone conduction and for detecting vital signals by means of a wearable device 10 according to the present invention.

The following will describe, by way of example, a case wherein the wearable device 10 is being worn at a user’s wrist and is connected to a smartphone, acting as an external device, via wireless communication.

At step 102, the wearable device 10 can receive a first signal 26 from an external smartphone via a communication unit 23 using a predetermined communication method, i.e. a wireless transmission.

At step 104, the control unit 21 amplifies the first signal 22 received from the communication unit 23 and generates a third signal 24.

At step 106, the at least one transducer 29,31 receives the third signal 24 and generates a corresponding vibration, which is transferred to the user’s wrist. Therefore, the user can put his/her finger against his/her ear, in particular on the cartilage, and hear the sound being transferred through the vibration.

At step 108, which occurs simultaneously with steps 102-106, the vital signals of the individual wearing the device 10 are detected through the vital signal departing from the at least one transducer 29,31 and from the second electrode, which, as previously described, may be either applied to another body part or formed on the device itself.

At step 110, the control unit 21 processes the received vital signals in order to supply instructions to an external device for drawing, on a display of the latter, an electrocardiogram of the individual who is wearing the device 10.

The present invention also concerns a system comprising a wearable device 10 as previously described herein and an external device that transmits an audio signal and vital signals to the wearable device 10 by using one of the above-described predefined communication methods.

The advantages of the device, system and method according to the present invention are apparent from the above description.

The wearable device according to the present invention advantageously permits establishing an audio communication via bone conduction and detecting vital signals by means of components so arranged as to take up little space.

Moreover, the wearable device according to the present invention is, advantageously, minimally invasive and ensures high levels of comfort and ergonomics while correctly reading vital signals.

The wearable device for effecting an audio communication via bone conduction, as well as the associated system and method, described herein by way of example may be subject to many possible variations without however departing from the novelty spirit of the inventive idea; it is also clear that in the practical implementation of the invention the illustrated details may have different shapes or be replaced with other technically equivalent elements.

For example, although the focus of this description is on a wearable device that can be worn around the wrist, such as a watch strap (Fig. 8e and Fig. 8f), a wristband (Fig. 8h), an armlet or a bracelet, it is nevertheless also applicable to other items wherein the wearable device will encircle, at least partially, a bone structure of an individual.

The wearable device 10 can therefore be used on other body parts comprising bone structures, e.g. a ring (Fig. 8a); a neckband or a necklace; a hairband (Fig. 8d), an earflap, a headband (Fig. 9h), a cap, a helmet (Fig. 8b and Fig. 8c); a garment, e.g. a t-shirt, a military jacket (Fig. 9a), a sports jacket (Fig. 9b), a tracksuit (Fig. 9e and Fig. 9g), a jersey, a jacket, a chest belt, trousers, a glove (Fig. 9c); glasses (Fig. 9d); a dummy (Fig. 8g); a gum shield (Fig. 9f). It can therefore be easily understood that the present invention is not limited to a wearable device for effecting an audio communication via bone conduction and to the associated system and method described herein by way of example, but may be subject to many modifications, improvements or replacements of equivalent parts and elements without departing from the inventive idea, as clearly specified in the following claims.

Claims

1. Wearable device (10) for effecting an audio communication via bone conduction and for detecting vital signals of an individual, comprising:

- means, in particular a communication unit (23), adapted to receive as input an audio signal (26);

- a control unit (21), in particular a microprocessor;

- an audio I/O unit (27), adapted to convert an audio signal into an electric signal, and vice versa;

- a transducer (29) arranged on an inner surface (13) of said device and adapted to generate a vibration corresponding to said input audio signal (26), characterized in that said transducer (29) is surrounded by a layer (32) of electrically conductive and sound-absorbent material, and constitutes a first electrode adapted to detect a first vital signal of said individual.

2. Wearable device (10) according to claim 1, wherein said inner surface (13) of said wearable device (10) comprises at least a second electrode adapted to detect a second vital signal of said individual.

3. Wearable device (10) according to claim 2, wherein said second electrode comprises a second transducer (31) surrounded by a layer (32) of electrically conductive and soundabsorbent material.

4. Wearable device (10) according to claim 2, wherein said second electrode comprises at least one region (45,46) of said inner surface (13) of said wearable device (10) that comprises a layer of electrically conductive and sound-absorbent material.

5. Wearable device (10) according to one or more of the preceding claims, wherein said layer (32) of electrically conductive and sound-absorbent material emerges, at least partly, in and from a region (32a) of said inner surface (14).

6. Wearable device (10) according to one or more of the preceding claims, wherein said layer (32) of electrically conductive and sound-absorbent material comprises one of the following materials: conductive rubber; conductive fabric; conductive foam; conductive sponge.

7. Wearable device (10) according to one or more of the preceding claims, wherein the layer (32) of electrically conductive and sound-absorbent material may be shaped as a closed container internally housing said transducer (29).

8. Wearable device (10) according to one or more of the preceding claims, wherein said layer (32) of electrically conductive and sound-absorbent material is buried in the structure of the material constituting said inner surface (14).

9. Wearable device (10) according to one or more of the preceding claims, wherein said transducer (29) comprises a coil (40) equipped with a magnetic element, and wherein a first conducting element (42) adapted to transport an audio communication signal, a second conducting element (44) adapted to be connected to the ground of said transducer (29) and a third conducting element (56) connected to said layer (32) of electrically conductive and sound-absorbent material extend from said transducer (29).

10. Wearable device (10) according to one or more of the preceding claims, wherein said audio I/O unit (27) comprises a microphone adapted to receive an audio signal from the outside environment and a loudspeaker for outputting an audio signal into the outside environment.

11. Wearable device (10) according to one or more of the preceding claims, wherein said device (10) comprises a power supply unit (25), in particular a battery.

12. Wearable device (10) according to claim 11, wherein said device (10) comprises a flexible printed circuit (50) comprising at least said control unit (21), said communication unit (23) and said power supply unit (25).

13. Wearable device (10) according to one or more of the preceding claims, wherein said device (10) comprises longitudinal coupling means (15,17) adapted to allow an individual to wear said device (10).

14. Wearable device (10) according to one or more of the preceding claims, wherein said wearable device (10) is one of the following items: watch strap; wristband; armlet; bracelet; ring; neckband; necklace; hairband; earflap; headband; cap; helmet; garment; t- shirt; military jacket; sports jacket; tracksuit; jersey; jacket; chest belt; trousers; glove; glasses; dummy; gum shield; or said wearable device (10) can be electrically connected to a repositionable remote electrode.

15. System comprising a wearable device (10) according to one or more of claims 1 to 14 and an external device, said wearable device (10) being adapted to transmit an audio signal and signals processed by said control unit (21) and representative of vital signals of an individual to said external device according to a predetermined communication method, said communication method comprising: Wi-Fi; Bluetooth; a global positioning system; a cellular communication; a code-division multiplex access; a universal mobile telecommunications system; a wireless broadband; a global system for mobile communications; a wireless communication, including a near-field communication; a wired communication method; a high-definition multimedia interface; a standard interface; a fixed telephone network.

16. System according to claim 15, wherein said external device comprises a mobile device, a smartphone, a tablet PC, a server or further wearable devices, said external device being equipped with a display for displaying an electrocardiogram of said individual.

17. Method for effecting an audio communication via bone conduction and for detecting vital signals of an individual by means of a wearable device (10), comprising the steps of:

- receiving as input an audio signal (26) via communication means (23) of said device (10), in particular a communication unit (23);

- converting an audio signal into an electric signal, and vice versa, through an audio I/O unit (27) of said device (10),

- generating a vibration corresponding to said input audio signal (26) by means of a transducer (29) arranged on an inner surface (13) of said device (10), said transducer (29) being controlled by a control unit (21) of said device (10), characterized in that it is envisaged to surround said transducer (29) with a layer (32) of electrically conductive and sound-absorbent material, so as to constitute a first electrode adapted to detect a first vital signal of said individual.

18. Method according to claim 17, wherein it is envisaged to provide said inner surface (13) of said wearable device (10) with at least a second electrode adapted to detect a second vital signal of said individual.

19. Method according to claim 18, wherein itis envisaged to realize said second electrode as a second transducer (31) surrounded by a layer (32) of electrically conductive and sound-absorbent material.

20. Method according to claim 18, wherein said second electrode is formed in at least one region (45,46) of said inner surface (13) of said wearable device (10) that comprises a layer of electrically conductive and sound-absorbent material.

21. Method according to one of claims 17 to 20, wherein it is envisaged to form said layer (32) of electrically conductive and sound-absorbent material in such a way that a region (32a) thereof emerges, at least partly, from said inner surface (14).

22. Method according to one of claims 17 to 21, wherein said layer (32) of electrically

- 17 - conductive and sound-absorbent material is made of one of the following materials: conductive rubber; conductive fabric; conductive foam; conductive sponge.

23. Method according to one of claims 17 to 22, wherein said layer (32) of electrically conductive and sound-absorbent material is shaped as a closed container internally housing said transducer (29).

24. Method according to one of claims 17 to 23, wherein said layer (32) of electrically conductive and sound-absorbent material is buried in the structure of the material constituting said inner surface (14), in particular by welding, screwing or gluing.