Method for determining a wearing state of a headphone and headphone system

Abstract

In a method for determining a wearing state of an earpiece, acceleration data are detected by means of an acceleration sensor of the earpiece, a time course of the acceleration data is determined, and a course section is determined from the time course of the acceleration data. The course section is formed by a first section and a second section directly following the first section in time, respectively, the first and second sections being defined by the course of the acceleration data between two zero crossings of the time course of the acceleration data following one another, respectively. Furthermore, a first wearing state of the earpiece is determined, in which the earpiece is worn on the ear, if a course section is determined having a first section with a positive course and a second section with a negative course, and if a first characteristic course is determined for the course section, and a second wearing state of the earpiece is determined, in which the earpiece is not worn on the ear, if a course section is determined having a first section with a negative course and a second section with a positive course, and if a second characteristic course is determined for the course section.

Description

BACKGROUND

[0001] Headphones worn on the head allow the user to conveniently obtain a wide variety of audio content, for example to play music, podcasts or telephone calls. Sometimes, interactive audio content is also provided for playback with headphones, wherein the content is adapted to the orientation of the user's head. This requires a determination of the orientation of the user's head, which is typically carried out with the aid of an inertial measurement system integrated into the headphones.

[0002] In addition, headphones often have a function for recognizing the wearing state. For this purpose, the headphones typically have a separate sensor with the aid of which it can be recognized whether the headphones are worn on the ear. The recognition of the wearing state makes it possible, for example, to automatically switch on and off the device, whereby the current consumption can be kept low.

[0003] Methods for recognizing the wearing state of headphones are based on the detection of the contact between the headphones and the ear, which can be taken with the aid of pressure sensors, temperature sensors, distance sensors or different biosensors. Methods of this type are described, for example, in US 2007 / 0274530 A1, US 2009 / 0154720 A1, US 2014 / 0016803 A1, US 9 998 817 B, US 10 045 111 B and KR 2014 0079214 A.

[0004] In other methods, a distance measurement between the device and the ear is carried out, which is carried out by optical sensors, distance sensors or proximity sensors. Methods of this type are disclosed, for example, in CN 108600886 A, CN 109257674 A, US 10 306 350 B, US 2015 / 0281421 A1 and US 2017 / 0244821 A1.

[0005] Methods for determining the wearing state of headphones that combine the aforementioned detection methods are disclosed in US 2016 / 0205475 A1, CN 108769853 A, US 2015 / 0078573 A1 and CN 105491469 A. SUMMARY

[0006] According to the application, a method for determining the wearing state of headphones according to the application and a headphone system according to the application are provided.

[0007] According to a first aspect of the application, the method for determining the wearing state of headphones comprises the following steps:

[0008] - detecting acceleration data of the headphones with the aid of an acceleration sensor integrated into the headphones;

[0009] - determining a temporal course of the acceleration data, wherein the magnitude of the gravitational acceleration is subtracted from the magnitude of the acceleration data;

[0010] - determining a course section from the temporal course of the acceleration data, wherein the course section is formed by a first section and a second section directly following the first section in time, respectively, and wherein the first section and the second section are defined by the course of the acceleration data between two zero crossings of the temporal course of the acceleration data following each other, respectively;

[0011] - determining a first wearing state of the earpiece, in which the earpiece is worn on the ear, if a course section with a first section with a positive course and a second section with a negative course is determined and if a first characteristic course is determined for the course section;

[0012] - determining a second wearing state of the earpiece, in which the earpiece is not worn on the ear, if a course section with a first section with a negative course and a second section with a positive course is determined and if a second characteristic course is determined for the course section.

[0013] According to a second aspect of the present application, an earpiece system is provided. The earpiece system comprises an earpiece and a processor device, the earpiece having an audio module and a sensor device, the audio module being arranged for outputting an audio signal, the sensor device having an acceleration sensor, the acceleration sensor being arranged for detecting an acceleration of the earpiece, the processor device being arranged for causing the earpiece to perform the method for determining a wearing state of the earpiece according to the first aspect of the present application.

[0014] The idea underlying the present application is to detect a wearing state of the earpiece on or off the ear by analyzing an acceleration signal of an acceleration sensor of the earpiece. In particular, a movement of the earpiece corresponding to "inserting into the ear" or guiding the earpiece onto the ear or a movement corresponding to "taking out of the ear" or moving the earpiece away from the ear is detected from a temporal course of the acceleration signal.

[0015] The guiding of the earphone onto the ear and the removal of the earphone from the ear can be divided into four phases, for example. It is assumed that the user first holds the earphone when guiding the earphone onto the ear, which results in a vibration in the acceleration signal. In a second phase, the user raises the earphone, which results in a strong acceleration in the direction of the ear, which is typically opposite to the direction of the gravitational acceleration. In a third phase, the earphone is slowly guided to the ear, wherein, due to the decreasing speed of the movement, an acceleration can be detected which points in the opposite direction to the acceleration in the second phase and thus in the direction of the gravitational acceleration. In a fourth phase, the earphone is inserted into the ear or placed over the ear, which can again be detected as a vibration in the acceleration signal. Similarly, the process of removing the earphone from the ear can be described. In a first phase, the earphone is loosened from the ear, which results in a vibration in the acceleration signal. In a second phase, the earphone is removed from the ear, which can be identified as a strong acceleration in the acceleration signal, wherein the acceleration typically points essentially in the direction of the gravitational acceleration. In a third phase, the movement slows down, whereby there is a negative acceleration in the acceleration signal in the opposite direction. Finally, the earphone is laid down, inserted into a pocket or otherwise stowed away, wherein a vibration typically occurs when the earphone is stabilized in the new position.

[0016] According to the application, the second and third phases are to be determined, in particular, from the temporal course of the acceleration signal. To this end, the magnitude of the acceleration data is determined, and the magnitude of the gravitational acceleration is subtracted from the magnitude of the acceleration data. Thereby, an acceleration signal is determined which is positive or negative depending on the direction of the acceleration. Although the gravitational direction points downwards (in the direction of the earth's center), the gravity which is actually measured by the acceleration sensor in the rest state is a positive counterforce which is applied upwards (away from the earth's center): +9.81 m / s 2Therefore, the magnitude of acceleration data containing upward (away from the Earth's center) acceleration will have a positive sign after subtracting the measured gravitational acceleration. Similarly, the magnitude of acceleration data containing downward (in the direction of the Earth's center) acceleration will have a negative sign after subtracting the measured gravitational acceleration. By determining the zero-crossing points of the acceleration signal, the temporal variation process can be divided into segments, where a segment is defined by the variation process of the signal between two temporally successive zero-crossing points. Two successive segments form a variation process segment of the acceleration signal. If a segment has a first temporal segment and a second temporal segment, where the signal variation process is positive in the first segment and negative in the second segment, this means that acceleration opposite to the direction of gravitational acceleration occurs first, followed by acceleration in the direction of gravitational acceleration. If the acceleration signal in this segment has a definite characteristic variation process, the movement of the headphones toward the ears can be inferred. Similarly, if a segment has a first temporal segment and a second temporal segment, in which the signal change process is negative and in which the signal change process is positive, and the segment has a definite characteristic change process, then the movement of the earphone away from the ear can be inferred.

[0017] Characteristic changes can correspond in particular to instantaneous, sinusoidal changes in segments of an acceleration signal, where the deviation from the changes in preceding and subsequent segments exceeds a threshold. For example, the deviation of the sum of integrals of this segment from the sum of integrals of preceding and / or subsequent segments can exceed a limit.

[0018] The advantage of this invention is that, by analyzing and processing the acceleration signal, only an accelerometer is needed to detect the wearing status. Since accelerometers are frequently used in headphones, for example, to determine the orientation of the headphones, the wearing status can be determined with a minimal number of components and with low space requirements for the sensing mechanism.

[0019] Another advantage is that, compared to other sensors, accelerometers have low power consumption, which advantageously reduces the power requirements of the headphones. Furthermore, accelerometers do not depend on a fixed arrangement within the headphones, as is the case with contact sensors or similar objects.

[0020] According to some implementation methods, if a change process segment satisfies one or more of the following conditions, then the first representative change process is extracted:

[0021] - The maximum and minimum values ​​of this segment are both greater than the predetermined thresholds;

[0022] - the time integral of the first section of the segment and the time integral of the second section of the segment are greater than a predetermined threshold, respectively;

[0023] - the duration of the segment is greater than a predetermined threshold;

[0024] - the sum of the magnitudes of the maximum and minimum of the segment is greater than the sum of the magnitudes of the maximum and minimum of the immediately preceding and immediately succeeding segments in time;

[0025] - the sum of the integrals of the first and second sections of the segment is greater than the sum of the integrals of the first and second sections of the immediately preceding segment and greater than the sum of the integrals of the first and second sections of the immediately succeeding segment;

[0026] - the magnitudes of the maximum and minimum of the segment are not significantly smaller than the magnitudes of the maximum and minimum in the immediately preceding segment and in the immediately succeeding segment.

[0027] According to some embodiments it can be provided that a second characteristic variation is taken if the variation course segment fulfils one or more of the following conditions:

[0028] - the magnitude of the maximum and the magnitude of the minimum of the segment are greater than a predetermined threshold, respectively;

[0029] - the time integral of the first section of the segment and the time integral of the second section of the segment are greater than a predetermined threshold, respectively;

[0030] - the duration of the segment is greater than a predetermined threshold;

[0031] - the sum of the magnitudes of the maximum and minimum of the segment is greater than the sum of the magnitudes of the maximum and minimum of the immediately preceding and immediately succeeding segments in time;

[0032] - the sum of the integrals of the first and second sections of the segment is greater than the sum of the integrals of the first and second sections of the immediately preceding segment and greater than the sum of the integrals of the first and second sections of the immediately succeeding segment;

[0033] - the magnitudes of the maximum and minimum of the segment are not significantly smaller than the magnitudes of the maximum and minimum in the immediately preceding segment and in the immediately succeeding segment.

[0034] The conditions described above for the first and second characterizing change processes offer the advantage that they can be readily determined computationally and reliably distinguish between change process segments representing "direction to the ear" or "removal from the ear." This ease of determination in terms of computational technology advantageously reduces the computational power of the headphone's processor, resulting in structural space advantages and further reductions in energy requirements.

[0035] According to some implementations, the determination of the time-varying process may additionally include low-pass filtering of the detected acceleration data. For example, the low-pass threshold frequency may be selected to be less than 2 Hz in order to suppress high-frequency sensor noise.

[0036] According to some implementations, the headphones can be configured to operate in a first operating mode if a first wearing state is determined, in which the headphone's audio module is activated to output an audio signal; and to operate in a second operating mode if a second wearing state is determined, in which the headphone's power consumption is reduced compared to the first operating mode. For example, in the second wearing state, i.e., when the headphones are removed from the ears, the audio module can switch from stereo output to mono output. It is also possible to completely shut down the audio module.

[0037] According to some implementations, the accelerometer can be configured to be a triaxial accelerometer, which is configured to detect acceleration in three mutually perpendicular spatial directions. This allows for the advantageous implementation of additional headphone functions; for example, the processor can be configured to determine the head orientation based on the acceleration signals from the triaxial accelerometer. Attached Figure Description

[0038] The invention will now be described with reference to the accompanying drawings. The drawings show:

[0039] Figure 1 A schematic block diagram of an earphone system according to an embodiment of the invention is shown;

[0040] Figure 2 This illustrates the temporal variation of the acceleration signal detected by the accelerometer in the headphones;

[0041] Figure 3 A flowchart illustrating a method for determining the wearing status of headphones according to an embodiment of the present invention is shown.

[0042] In the accompanying drawings, the same reference numerals denote the same or functionally identical parts, unless otherwise stated to the contrary. Detailed Implementation

[0043] Figure 1 A schematic block diagram of the earphone system 100 is exemplarily shown. As Figure 1 The earphone system 100 can have at least one earphone 1 and a processor device 110, as exemplarily shown inThe earphone system 100 can also have more than one earphone 1, for example a first and a second earphone 1, for example. The earphone 1 can generally be implemented as an in-ear earphone which is arranged for being partially introduced into an ear canal. Alternatively, it can be considered that the earphone is implemented as a on-ear earphone or an over-ear earphone which is worn on or over the ear.

[0044] The earphone 1 can have an audio module 2 and an orientation sensor device 3, as Figure 1 The processor device 110 can be integrated into the earphone 1, as also exemplarily shown in Figure 1 The audio module 2 can have in particular a loudspeaker which is arranged for outputting an audio signal. Optionally, the audio module 2 can also have a microphone (not shown) which is arranged for detecting an acoustic signal.

[0045] The orientation sensor device 3 can have in particular an acceleration sensor 30. Optionally, a rotation rate sensor 31 can additionally be provided, and also optionally a magnetic sensor 32, as exemplarily shown in

[0046] The orientation sensor device 3 can thus have for example an inertial measurement unit, in short IMU. The processor device 110 can be part of the orientation sensor device 3. The optional magnetic sensor 32 is preferably attached to the IMU or the processor device 110. Figure 1 The acceleration sensor 30 can have a first sensor element 30x for detecting an acceleration along a first spatial direction, a second sensor element 30y for detecting an acceleration along a second spatial direction, and a third sensor element 30z for detecting an acceleration along a third spatial direction, as exemplarily shown in

[0047] Figure 1 The acceleration sensor 30 can have a first sensor element 30x for detecting an acceleration along a first spatial direction, a second sensor element 30y for detecting an acceleration along a second spatial direction, and a third sensor element 30z for detecting an acceleration along a third spatial direction, as exemplarily shown in

[0048] The acceleration sensor 30 can have a first sensor element 30x for detecting an acceleration along a first spatial direction, a second sensor element 30y for detecting an acceleration along a second spatial direction, and a third sensor element 30z for detecting an acceleration along a third spatial direction, as exemplarily shown in Figure 1In addition, the optional rotation speed sensor 31 can have a first sensor element 31x for detecting the rotation speed about the first spatial direction or the first axis, a second sensor element 31y for detecting the rotation speed about the second spatial direction or the second axis, and a third sensor element 31z for detecting the rotation speed about the third spatial direction or the third axis. In general, the rotation speed sensor 31 is arranged for detecting the rotation speed of the first reference system RF1 relative to each of the three spatial directions x', y', z' and outputs a corresponding rotation speed signal.

[0049] The optional magnetic field sensor 32 can have a first sensor element 32x for detecting the magnetic field along the first spatial direction or the first axis x', a second sensor element 32y for detecting the magnetic field along the second spatial direction or the second axis y', and a third sensor element 32z for detecting the magnetic field along the third spatial direction or the third axis z'. In general, the magnetic field sensor 32 is arranged for detecting the orientation of the earphone 1 relative to the earth's magnetic field and outputs a corresponding orientation signal. Thus, a digital compass is realized, by which the orientation of the earphone 1 relative to the magnetic north pole can be determined.

[0050] The processor device 110 can generally have a processor and a data memory. For example, the processor device 110 can be implemented as a microprocessor. The processor device 110 is connected to the orientation sensor device 3 in a signal-conducting manner and can be arranged, inter alia, for processing the signals output by the orientation sensor device 3, inter alia, in accordance with the method described below.

[0051] In addition, the earphone 1 can have an energy storage device, for example a battery, for storing electrical energy, to which the sensor device 3 and the processor device 110 are connected.

[0052] Figure 2 The course of the acceleration signal S over time T is shown exemplarily, which is detected by means of the acceleration sensor 30. In Figure 3 A flowchart of a method for determining the wearing state of the earphone 1 is shown in Figure 1 The method M can be implemented, for example, by means of the earphone system 100 shown in

[0053] As Figure 3 In a first step M1, acceleration data are detected by means of the acceleration sensor 30 integrated into the earphone 1, as shown exemplarily in

[0054] In a further step M2, a time course of the acceleration data is determined. In particular, a magnitude of the acceleration data can be determined, and a magnitude of the gravitational acceleration can be subtracted from the magnitude of the acceleration data. Thereby, accelerations opposite to the direction of gravity or away from the earth's center obtain a positive sign, while accelerations in the direction of gravity or in the direction of the earth's center obtain a negative sign. The reason is that the acceleration sensor 30 measures in the resting state a counter force opposite to the gravity, which has a positive sign or has the value +9.81 m / s 2 . Optionally, a low pass filtering of the detected acceleration data can additionally be performed, for example by means of a low pass with a limiting frequency of less than 2 Hz, in order to suppress high-frequency sensor noise. In this way, for example, the time course exemplary shown in Figure 2 can be determined. The acceleration data can be temporarily stored in a data memory of the processor device 110, for example over a determined time period.

[0055] Therefore, the magnitude of the acceleration data s over time T is shown in Figure 2 . Since the acceleration sensor 30 measures in the resting state a counter force opposite to the gravity, which has a positive sign or has the value +9.81 m / s 2 , the abscissa formed by the time axis T corresponds to the value of the gravitational acceleration, which is measured by the acceleration sensor 30 when the acceleration sensor 30 is at rest. Therefore, in the case of an acceleration "upwards" or away from the earth's center or opposite to the direction of gravity, the magnitude of the acceleration data S shown in Figure 2 has a positive sign. Correspondingly, in the case of an acceleration "downwards" or in the direction of the earth's center or opposite to the direction of gravity, the magnitude of the acceleration data has a negative magnitude.

[0056] In a further step M3, from the time course of the acceleration data, a course section VS1, VS2, VS3, VS4 of the variation is determined. In particular, for this purpose, zero crossings of the time course of the acceleration data can be determined. Thereby, the time course of the acceleration data is divided into individual sections A11, A12, A21, A22, A31, A32, A41, A42. Each course section VS1, VS2, VS3, VS4 is defined by two sections A11, A12, A21, A22, A31, A32, A41, A42 directly subsequent to each other in time. In Figure 2In the example, a change process segment VS1 is defined, for example, by the first section Al 1 and the second section A12. A change process segment VS2, which temporally follows the change process segment VS1, is defined by the first section A21 and the second section A22, wherein the first section A21 of the change process segment VS2 corresponds to the second section A12 of the change process segment VS1. Likewise, a change process segment VS3 is defined by the first section A31 and the second section A32. A change process segment VS4, which temporally follows the change process segment VS3, is defined by the first section A41 and the second section A42, wherein the first section A41 of the change process segment VS4 corresponds to the second section A32 of the change process segment VS3. Thus, each change process segment VS1, VS2, VS3, VS4 is formed by a first section Al 1, A21, A31, A41, respectively, and a second section A12, A22, A32, A42, which directly follows the first section in time, wherein the first section Al 1, A21, A31, A41 and the second section A12, A22, A32, A42 are defined by the change process of the acceleration data between two zero crossings of the change process, which follow one another, respectively, in time of the acceleration data.

[0057] In a step M4, a first wearing state of the earphone 1 is determined, in which the earphone 1 is worn on the ear. In a step M5, a second wearing state of the earphone 1 is determined, in which the earphone 1 is not worn on the ear. The wearing state of the earphone 1 is determined depending on the analysis of the change process or the change process segments VS1, VS2, VS3, VS4 in time of the acceleration data in the steps M45 and M55.

[0058] The guiding of the earphone 1 onto the ear and the removal of the earphone 1 from the ear can essentially be divided into four phases. It is assumed that the user first holds the earphone 1 when guiding the earphone 1 onto the ear, which leads to vibrations in the acceleration signal. This can be seen in Figure 2 In the second phase, the user lifts the earphone 1, which leads to a strong acceleration in the direction of the ear, which is typically directed against the direction of the gravitational acceleration or away from the earth's center or "upward". This can be seen in Figure 2 In the third phase, the earphone is slowly guided to the ear, wherein due to the decreasing speed of the movement, an acceleration opposite to the acceleration in the second phase and thus in the direction of the gravitational acceleration or in the direction of the earth's center or "downward" directed can be detected, as is the case in Figure 2 In the fourth phase, the earphone is inserted into the ear 1 or placed over the ear, which can again be detected as vibrations in the acceleration signal, as is the case in Figure 2The process of removing the earpiece 1 from the ear can be seen on the exemplary change process in segment A42 and in the segments following in time. Similarly, the process of putting the earpiece 1 on the ear can be seen on the exemplary change process in Figure 2 The process of removing the earpiece 1 from the ear can be seen on the exemplary change process in segment A42 and in the segments following in time. Similarly, the process of putting the earpiece 1 on the ear can be seen on the exemplary change process in Figure 2 The process of removing the earpiece 1 from the ear can be seen on the exemplary change process in segment A42 and in the segments following in time. Similarly, the process of putting the earpiece 1 on the ear can be seen on the exemplary change process in Figure 2 The process of removing the earpiece 1 from the ear can be seen on the exemplary change process in segment A42 and in the segments following in time. Similarly, the process of putting the earpiece 1 on the ear can be seen on the exemplary change process in Figure 2 The process of removing the earpiece 1 from the ear can be seen on the exemplary change process in segment A42 and in the segments following in time. Similarly, the process of putting the earpiece 1 on the ear can be seen on the exemplary change process in

[0059] In the stationary state of the earpiece 1, the magnitude of the acceleration signal corresponds to the gravitational acceleration. As can be seen on the exemplary change process in Figure 2 The process of removing the earpiece 1 from the ear can be seen on the exemplary change process in segment A42 and in the segments following in time. Similarly, the process of putting the earpiece 1 on the ear can be seen on the exemplary change process in Figure 2 The process of removing the earpiece 1 from the ear can be seen on the exemplary change process in segment A42 and in the segments following in time. Similarly, the process of putting the earpiece 1 on the ear can be seen on the exemplary change process in Figure 3 The process of removing the earpiece 1 from the ear can be seen on the exemplary change process in segment A42 and in the segments following in time. Similarly, the process of putting the earpiece 1 on the ear can be seen on the exemplary change process in

[0060] Therefore, in step M45 of the method M, a change process segment VS1, VS2, VS3, VS4 having a first characteristic change process or a second characteristic change process is determined from the temporal change process of the acceleration signal. The determination of the change process segment VS1, VS2, VS3, VS4 having the first characteristic change process or the second characteristic change process can comprise, for example, a temporal integration of the individual segments A11, A12, A21, A22, A31, A32 and / or a determination of the maximum and minimum values of the magnitudes of the segments A11, A12, A21, A22, A31, A32 and / or a determination of the duration of the segments A11, A12, A21, A22, A31, A32. A change process segment having the first or the second characteristic change process can be detected when one or more of the following conditions are fulfilled:

[0061] - the magnitude of the maximum value and the magnitude of the minimum value of the segment are greater than a predetermined threshold value, respectively;

[0062] - the time integral of the first section of the segment and the time integral of the second section of the segment are greater than a predetermined threshold value, respectively;

[0063] - the duration of the segment is greater than a predetermined threshold value;

[0064] - the sum of the magnitude of the maximum value and the magnitude of the minimum value of the segment is greater than the sum of the magnitude of the maximum value and the magnitude of the minimum value of the segment directly preceding in time and of the segment directly succeeding in time;

[0065] - the sum of the integrals of the first and second sections of the segment is greater than the sum of the integrals of the first and second sections of the segment directly preceding in time and greater than the sum of the integrals of the first and second sections of the segment directly succeeding in time;

[0066] - the magnitude of the maximum value and the magnitude of the minimum value of the segment are not significantly smaller than the magnitude of the maximum value and the magnitude of the minimum value in the segment directly preceding in time and in the segment directly succeeding in time.

[0067] In step M45 it is checked for the presence of one or more of these conditions. If one or more of these conditions is not fulfilled, the method returns to step M1, as this is indicated in Figure 3 by the symbol "-". If one or more of these conditions is fulfilled, step M55 is implemented next, as this is indicated in Figure 2 by the symbol "+". In Figure 2 , for example the change process segments VS1 and VS3 fulfil one or more of these conditions.

[0068] In step M55 it is checked whether a change process segment VS1, VS2, VS3, VS4 with a characteristic change process has a first section A11, A21, A31, A41 with a positive change process and a second section A12, A22, A32, A42 directly following the first section in time with a negative change process. This is the case in Figure 3 , for example for the change process segment VS3. As mentioned above, the change process segment VS3 represents the introduction of the earphone 1 onto the ear. In correspondence therewith, it is determined in step M4 next that the first wearing state of the earphone 1 is present, in which the earphone 1 is worn on the ear, as this is indicated in Figure 2 by the symbol "*".

[0069] Furthermore, it is checked in step M55 whether the change profile section VS1, VS2, VS3, VS4 having a characteristic change profile has a first section A11, A21, A31, A41 with a negative change profile and a second section A12, A22, A32, A42 with a positive change profile directly following the first section in time. This case corresponds in Figure 3 to the change profile section VS1 in ​ As described above, the change profile section VS1 represents the removal of the earphone 1 from the ear. In correspondence therewith, it is determined in step M5, as this is marked by the symbol "#" in ​ , that a first wearing state of the earphone 1 exists in which the earphone 1 is worn on the ear.

[0070] Alternatively, if the first wearing state is determined, the earphone can be operated in step M6 in a first operating mode in which the audio module 2 of the earphone 1 is activated to output an audio signal. This can correspond, for example, to an automatic switching on of the audio module 2. Likewise, if the second wearing state is determined, the earphone 1 can be operated in an optional step M7 in a second operating mode in which the energy consumption of the earphone 1 is reduced compared to the first operating mode. For example, the audio module can be switched off in step M7 and optionally further components of the earphone can be switched off.

[0071] Although the application has been illustrated above in accordance with the embodiments, the application is not limited thereto, but can be modified in various ways. In particular, combinations of the above-described embodiments can also be considered.

Claims

1. A method (M) for determining the wearing state of an earphone (1), the method comprising: Acceleration data of the earphone (1) is detected (M1) by means of an accelerometer (30) integrated into the earphone (1); The process of changing the acceleration data over time is obtained (M2), wherein the magnitude of gravitational acceleration is subtracted from the magnitude of the acceleration data; The change process segments (VS1, VS2, VS3, VS4) are obtained from the temporal change process of the acceleration data. The change process segments (VS1, VS2, VS3, VS4) are formed by a first segment (A11, A21, A31, A41) and a second segment (A12, A22, A32, A42) that directly follows the first segment in time. The first segment (A11, A21, A31, A41) and the second segment (A12, A22, A32, A42) are defined by the change process of the acceleration data between two successive zero crossings in the temporal change process of the acceleration data. If the change process segments (VS1, VS2, VS3, VS4) with a first segment (A11, A21, A31, A41) having a positive change process and a second segment (A12, A22, A32, A42) having a negative change process are obtained (M55), and if the first characteristic change process of (M55) is obtained for the change process segments (VS1, VS2, VS3, VS4), then the first wearing state of the earphone (1) is determined (M4), in which the earphone (1) is worn on the ear; If (M55) is obtained, the change process segments (VS1, VS2, VS3, VS4) having a first segment (A11, A21, A31, A41) with a negative change process and a second segment (A12, A22, A32, A42) with a positive change process are obtained, and if (M45) is obtained for the change process segments (VS1, VS2, VS3, VS4), then (M5) is determined to be the second wearing state of the earphone (1), in which the earphone (1) is not worn on the ear.

2. The method according to claim 1, wherein, If the change process segments (VS1, VS2, VS3, VS4) satisfy one or more of the following conditions, then the first representative change process is extracted: - The maximum and minimum values ​​of the segment are both greater than a predetermined threshold; - The time integrals of the first segment and the second segment of the segment are both greater than predetermined thresholds; - The duration of the segment is greater than a predetermined threshold; - The sum of the maximum and minimum values ​​of the segment is greater than the sum of the maximum and minimum values ​​of the segments that are directly preceding and directly following in time; - The sum of the integrals of the first and second segments of the segment is greater than the sum of the integrals of the first and second segments of the segment that comes first in time, and is also greater than the sum of the integrals of the first and second segments of the segment that comes second in time. - The magnitudes of the maximum and minimum values ​​of the segment are not significantly less than the magnitudes of the maximum and minimum values ​​of the segment that precedes it in time and the segment that follows it in time.

3. The method according to claim 1 or 2, wherein, If the change process segments (VS1, VS2, VS3, VS4) satisfy one or more of the following conditions, then the second representative change process is extracted: - The maximum and minimum values ​​of the segment are both greater than a predetermined threshold; - The time integrals of the first segment and the second segment of the segment are both greater than predetermined thresholds; - The duration of the segment is greater than a predetermined threshold; - The sum of the maximum and minimum values ​​of the segment is greater than the sum of the maximum and minimum values ​​of the segments that are directly preceding and directly following in time; - The sum of the integrals of the first and second segments of the segment is greater than the sum of the integrals of the first and second segments of the segment that comes first in time, and is also greater than the sum of the integrals of the first and second segments of the segment that comes second in time. - The magnitudes of the maximum and minimum values ​​of the segment are not significantly less than the magnitudes of the maximum and minimum values ​​of the segment that precedes it in time and the segment that follows it in time.

4. The method according to any one of claims 1 to 3, wherein, The determination of the time-varying process additionally includes low-pass filtering of the detected acceleration data.

5. The method according to any one of claims 1 to 4, wherein the method additionally comprises: If the first wearing state is determined, the earphone (1) is operated in the first operating mode (M6). In the first operating mode, the audio module (2) of the earphone (1) is activated to output an audio signal. If the second wearing state is determined, the earphone (1) is operated in the second operating mode (M7), in which the energy consumption of the earphone (1) is reduced compared to the first operating mode.

6. A headphone system (100), the headphone system comprising: The earphone (1) has an audio module (2) and a sensor device (30), the audio module being configured to output an audio signal, and the sensor device having an accelerometer (30) being configured to detect the acceleration of the earphone (1); A processor device (110) configured to cause the earphone (1) to perform the method according to any one of claims 1 to 5.

7. The headphone system (100) according to claim 6, wherein, The accelerometer (30) is a triaxial accelerometer configured to detect acceleration in three mutually perpendicular spatial directions.

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