Head measurement method, wearable device and adjustment method therefor

Abstract

A head measurement method, a wearable device and an adjustment method therefor. The head measurement method is executed by a wearable device, and the wearable device is provided with a magnetic transmitter and a plurality of magnetic receivers. The head measurement method comprises: when two ends of the wearable device are in contact with two contact points of the head of a user and the magnetic transmitter transmits a magnetic signal, acquiring current magnetic induction data of each magnetic receiver (S110); on the basis of the current magnetic induction data of each magnetic receiver, determining a distance between the two contact points of the head of the user (S120); and on the basis of the distance between the two contact points of the head of the user, determining the size of the head of the user (S130). The method is implemented by the wearable device provided with one magnetic transmitter and the plurality of magnetic receivers, and when the user wears the wearable device, the size of the head of the user can be rapidly measured by means of the magnetic induction data received by the plurality of magnetic receivers, thereby greatly improving the convenience and accuracy of head measurement compared with traditional visual measurement and manual measurement solutions.

Description

Head measurement method, wearable device and adjustment method thereof

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the China Patent Office on June 30, 2023, with application number 202310804397.9, and invention name “Head measurement method, wearable device and adjustment method thereof”, the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present application relates to the field of head measurement technology, and in particular to a head measurement method, a wearable device and an adjustment method thereof. Background Art

[0004] The user's head size data is an important parameter data in the fields of virtual interaction, medical treatment, beauty care, etc., and how to measure the user's head size is a problem that needs to be solved.

[0005] Current solutions for measuring user head size mainly rely on visual measurement or manual measurement. However, these measurement methods have problems such as cumbersome measurement process and inaccurate results.

[0006] Summary of the Invention

[0007] The embodiments of the present application provide a head measurement method, a wearable device, and an adjustment method thereof to improve the convenience and accuracy of head measurement.

[0008] The embodiments of this application adopt the following technical solutions:

[0009] In a first aspect, an embodiment of the present application provides a head measurement method, which is performed by a wearable device, wherein the wearable device is provided with a magnetic transmitter and a plurality of magnetic receivers, and the head measurement method includes:

[0010] When two ends of the wearable device are in contact with two contact points on the user's head and the magnetic transmitter emits a magnetic signal, obtaining current magnetic induction data of each magnetic receiver;

[0011] determining the distance between the two contact points on the user's head based on current magnetic induction data from each magnetic receiver;

[0012] The size of the user's head is determined according to the distance between the two contact points on the user's head.

[0013] Optionally, determining the distance between the two contact points on the user's head according to current magnetic induction data of each magnetic receiver includes:

[0014] Obtaining a calibration correspondence between the magnetic induction data of each magnetic receiver and the distance between the two contact points on the user's head;

[0015] The distance between the two contact points on the user's head is determined according to the current magnetic induction data of each magnetic receiver and the calibration correspondence.

[0016] Optionally, obtaining a calibration correspondence between the magnetic induction data of each magnetic receiver and the distance between two contact points on the user's head includes:

[0017] adjusting an opening angle of the wearable device according to a plurality of preset distances between two contact points on the user's head;

[0018] acquiring magnetic induction data of each magnetic receiver based on the opening angle of the wearable device;

[0019] Based on the spatial geometric structure information of the wearable device, the calibration correspondence is constructed according to the magnetic induction data of each magnetic receiver and each preset distance.

[0020] Optionally, determining the distance between the two contact points on the user's head according to the current magnetic induction data of each magnetic receiver and the calibration correspondence includes:

[0021] Determining, based on the current magnetic induction data of each magnetic receiver and the calibration correspondence, a distance between two contact points on the user's head corresponding to the current magnetic induction data of each magnetic receiver;

[0022] The distances between the two contact points on the user's head corresponding to the current magnetic induction data of each magnetic receiver are fused to obtain a final distance between the two contact points on the user's head.

[0023] Optionally, the wearable device has an arc-shaped structure, the magnetic transmitter is provided in the middle of the arc-shaped structure, and the first and second magnetic receivers are respectively provided at both ends of the arc-shaped structure for contacting the user's head, and the current magnetic induction data of each magnetic receiver includes the first magnetic induction data of the first magnetic receiver and the second magnetic induction data of the second magnetic receiver.

[0024] Determining the distance between the two contact points on the user's head according to the current magnetic induction data of each magnetic receiver includes:

[0025] determining a first relative angle between the magnetic transmitter and the first magnetic receiver according to the first magnetic induction data;

[0026] determining a second relative angle between the magnetic transmitter and the second magnetic receiver according to the second magnetic induction data;

[0027] Determine a distance between two contact points on the user's head based on the first relative angle, the second relative angle, and the spatial geometric structure information of the wearable device.

[0028] Optionally, determining the distance between the two contact points on the user's head according to the first relative angle, the second relative angle, and the spatial geometric structure information of the wearable device includes:

[0029] determining an opening angle of the wearable device according to the first relative angle and the second relative angle;

[0030] The distance between the two contact points on the user's head is determined by using a trigonometric function according to the opening angle of the wearable device and the spatial geometric structure information of the wearable device.

[0031] In a second aspect, an embodiment of the present application further provides a head measurement device, which is applied to a wearable device. The wearable device is provided with a magnetic transmitter and a plurality of magnetic receivers. The head measurement device includes:

[0032] a first acquiring unit, configured to acquire current magnetic induction data of each magnetic receiver when two ends of the wearable device are in contact with two contact points on the user's head and the magnetic transmitter emits a magnetic signal;

[0033] a first determining unit, configured to determine a distance between two contact points on the user's head based on current magnetic induction data of each magnetic receiver;

[0034] The second determining unit is configured to determine the size of the user's head according to the distance between the two contact points on the user's head.

[0035] In a third aspect, an embodiment of the present application further provides a device for constructing a three-dimensional head model, the device comprising:

[0036] A second obtaining unit is used to obtain the user's head size;

[0037] a third determining unit, configured to determine key point information of the user's head according to the size of the user's head;

[0038] a fourth determining unit, configured to determine a three-dimensional head model of the user according to the head size of the user and key point information of the head of the user;

[0039] The user's head size is obtained based on any of the aforementioned head measurement methods.

[0040] In a fourth aspect, an embodiment of the present application further provides an adjustment device for a wearable device, the adjustment device for the wearable device comprising:

[0041] A third obtaining unit is used to obtain the user's head size;

[0042] a fifth determining unit, configured to determine a contact state between the wearable device and the user's head according to a size of the user's head;

[0043] a sixth determining unit, configured to adjust an opening angle of the wearable device according to a contact state between the wearable device and the user's head, so that the opening angle of the wearable device is adapted to a size of the user's head;

[0044] The user's head size is obtained based on any of the aforementioned head measurement methods.

[0045] In a fifth aspect, an embodiment of the present application further provides a wearable device, comprising:

[0046] a magnetic transmitter and a plurality of magnetic receivers;

[0047] processor; and

[0048] A memory is arranged to store computer executable instructions, which when executed cause the processor to perform any of the aforementioned head measurement methods.

[0049] In a sixth aspect, an embodiment of the present application further provides a computer-readable storage medium, which stores one or more programs. When the one or more programs are executed by a wearable device including multiple applications, the wearable device executes any of the aforementioned methods.

[0050] At least one of the above technical solutions adopted in the embodiments of the present application can achieve the following beneficial effects: the head measurement method of the embodiment of the present application is performed by a wearable device, which is provided with a magnetic transmitter and multiple magnetic receivers. When performing head measurement, the current magnetic induction data of each magnetic receiver is first obtained when the two ends of the wearable device are in contact with the user's head and the magnetic transmitter emits a magnetic signal; then, based on the current magnetic induction data of each magnetic receiver, the distance between the two contact points where the two ends of the wearable device are in contact with the user's head is determined; finally, based on the distance between the two contact points where the two ends of the wearable device are in contact with the user's head, the user's head size is determined. The head measurement method of the embodiment of the present application is implemented based on a wearable device provided with a magnetic transmitter and multiple magnetic receivers. After the user wears the wearable device, the user's head size can be quickly measured through the magnetic induction data received by the multiple magnetic receivers. Compared with traditional visual measurement and manual measurement solutions, the convenience and accuracy of head measurement are greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0052] FIG1 is a schematic diagram of a head measurement method according to an embodiment of the present application;

[0053] FIG2 is a schematic diagram of an ideal magnetic dipole emitting magnetic field in an embodiment of the present application;

[0054] FIG3 is a schematic diagram of a magnetic field emitted by a magnetic transmitter provided on a wearable device according to an embodiment of the present application;

[0055] FIG4 is a schematic diagram of a head measurement process in an embodiment of the present application;

[0056] FIG5 is a schematic diagram of a flow chart of a method for constructing a three-dimensional head model according to an embodiment of the present application;

[0057] FIG6 is a schematic diagram of a flow chart of a method for adjusting a wearable device according to an embodiment of the present application;

[0058] FIG7 is a schematic structural diagram of a head measurement device according to an embodiment of the present application;

[0059] FIG8 is a schematic structural diagram of a device for constructing a three-dimensional head model according to an embodiment of the present application;

[0060] FIG9 is a schematic structural diagram of an adjustment device for a wearable device according to an embodiment of the present application;

[0061] FIG10 is a schematic structural diagram of a wearable device in an embodiment of the present application. DETAILED DESCRIPTION

[0062] To make the purpose, technical solutions, and advantages of this application more clear, the technical solutions of this application will be clearly and completely described below in conjunction with the specific embodiments of this application and the corresponding drawings. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0063] The following describes in detail the technical solutions provided by various embodiments of the present application in conjunction with the accompanying drawings.

[0064] An embodiment of the present application provides a head measurement method, which is performed by a wearable device. The wearable device is provided with a magnetic transmitter and multiple magnetic receivers. As shown in FIG1 , a flow chart of a head measurement method in an embodiment of the present application is provided. The head measurement method includes at least the following steps S110 to S130:

[0065] Step S110 : When both ends of the wearable device are in contact with two contact points on the user's head and the magnetic transmitter emits a magnetic signal, current magnetic induction data of each magnetic receiver is obtained.

[0066] The head measurement method of the embodiment of the present application is performed by an independently designed wearable device. The wearable device here can be regarded as a head-mounted device that can be worn on the user's head. For example, it can be any form of headband, headband, hair ring, etc. Its main function is to serve as an auxiliary positioning device for beauty care equipment. That is, when the user wears the wearable device of the embodiment of the present application and holds the beauty care device for care operations, the wearable device can be used to locate the face or head area where the beauty care device acts, thereby achieving the purpose of precise skin care. For specific implementation, please refer to the introduction of relevant solutions, which will not be elaborated here.

[0067] In addition to the aforementioned positioning function, embodiments of the present application further expand the functionality of the wearable device by utilizing it to measure the size of a user's head. This requires the wearable device to be equipped with at least one magnetic transmitter and multiple magnetic receivers, thereby enabling head size measurement through electromagnetic induction technology. Of course, the specific locations and number of magnetic transmitters and receivers can be flexibly adjusted by those skilled in the art based on actual needs and are not specifically limited herein.

[0068] Based on the design of the above hardware structure, when implementing the head measurement method of the embodiment of the present application, the user needs to first wear the wearable device. When the two ends of the wearable device are in contact with the two contact points on the user's head, the magnetic transmitter is controlled to emit a magnetic signal to obtain the current magnetic induction data received by each magnetic receiver.

[0069] The contact situation can be determined, for example, by using built-in contact sensors at both ends of the wearable device. The capacitance change sensed by the contact sensors can be used to determine whether the two ends of the wearable device are in contact with the two contact points on the user's head.

[0070] Step S120 : determining the distance between the two contact points of the user's head according to the current magnetic induction data of each magnetic receiver.

[0071] Taking a wearable device in the form of a headband as an example, after the user puts on the wearable device, the distance between the two contact points on the user's head will mainly affect the size of the wearable device's opening angle. That is, when the distance between the two contact points on the user's head is different, the opening angle of the wearable device will also change to varying degrees, which will in turn cause the magnetic field strength induced by the magnetic receiver set on the wearable device to change, thereby generating different magnetic induction data. Therefore, it can be determined that there is a correlation between the distance between the two contact points on the user's head and the current magnetic induction data of the magnetic receiver.

[0072] Based on this, the embodiment of the present application can determine the distance between the two contact points on the user's head based on the current magnetic induction data received by multiple magnetic receivers, using certain strategies such as a method based on a pre-calibrated correspondence or a real-time solution method.

[0073] Step S130: Determine the size of the user's head according to the distance between the two contact points on the user's head.

[0074] The size of a user's head can be characterized by data in multiple dimensions, such as head width, head length, and head circumference. Based on the wearing characteristics of the aforementioned wearable device on the user's head, the distance between two contact points on the user's head can reflect the width of the user's head. This can also be used to calculate other dimensions of head size data. For example, the distance between the two contact points can be used as the diameter of a circle to calculate the circumference of the circle, and the circumference of the circle can be used as the user's head circumference. Of course, those skilled in the art can flexibly choose which dimensions of head size data to measure based on actual needs, and this is not specifically limited here.

[0075] The head measurement method of the embodiment of the present application is implemented based on a wearable device equipped with a magnetic transmitter and multiple magnetic receivers. After the user puts on the wearable device, the magnetic induction data received by the multiple magnetic receivers can be used to quickly measure the user's head size. Compared with traditional visual measurement and manual measurement solutions, the convenience and accuracy of head measurement are greatly improved.

[0076] In some embodiments of the present application, determining the distance between the two contact points on the user's head based on the current magnetic induction data of each magnetic receiver includes: obtaining a calibrated correspondence between the magnetic induction data of each magnetic receiver and the distance between the two contact points on the user's head; and determining the distance between the two contact points on the user's head based on the current magnetic induction data of each magnetic receiver and the calibrated correspondence.

[0077] As mentioned above, the embodiment of the present application can determine the distance between the two contact points on the current user's head based on the calibration correspondence between the magnetic induction data calibrated offline in advance and the distance between the two contact points on the user's head. The "calibration correspondence" here can be understood as the correspondence between the distance between the two contact points on different users' heads and the magnetic induction data of each magnetic receiver.

[0078] The reason for calibrating the distance between the two contact points corresponding to "multiple magnetic receivers" is mainly to take into account the differences in the user's wearing method each time and the differences in the wearing methods of different users, which may cause the magnetic induction data received by a single magnetic receiver to be inaccurate. Therefore, by combining the magnetic induction data of multiple magnetic sensors, the accuracy of head measurement can be improved.

[0079] In some embodiments of the present application, obtaining the calibration correspondence between the magnetic induction data of each magnetic receiver and the distance between the two contact points of the user's head includes: adjusting the opening angle of the wearable device according to multiple preset distances between the two contact points of the user's head; obtaining the magnetic induction data of each magnetic receiver based on the opening angle of the wearable device; and constructing the calibration correspondence according to the magnetic induction data of each magnetic receiver and each preset distance based on the spatial geometric structure information of the wearable device.

[0080] When calibrating this correspondence, multiple distance values ​​between two contact points on the user's head can be preset. These values ​​can be flexibly set based on the head width range of a large number of users. Based on these preset distance values, the wearable device's opening angle is adjusted accordingly. At each opening angle, each magnetic receiver on the wearable device will output corresponding magnetic induction data. This allows the magnetic induction data of each magnetic receiver corresponding to each opening angle to be obtained, thereby establishing a correspondence between the distance between the two contact points on the user's head and the magnetic induction data of each magnetic receiver.

[0081] For example, when the preset distance value is 15 cm, the opening angle of the wearable device is adjusted so that the distance between the two ends of the wearable device is 15 cm. At this time, each magnetic receiver on the wearable device will output a magnetic induction reading, and these magnetic induction readings all correspond to the distance value of 15 cm.

[0082] It should be noted that in the above embodiments, when adjusting the opening angle of the wearable device based on multiple preset distances, the opening angle does not need to be actually measured. Because the size and structure of the wearable device are known during the calibration phase, the actual distance between the two ends of the wearable device can be measured by physical measurement, etc., and the distance can be equal to the preset multiple distance values. The opening angle here is only used to indicate that the change in the distance between the two ends of the wearable device is achieved by adjusting the size of the bend or opening angle of the wearable device.

[0083] To facilitate understanding of the embodiments of the present application, the coil of the magnetic transmitter can be regarded as an ideal magnetic dipole. As shown in FIG2 , a schematic diagram of an ideal magnetic dipole transmitting a magnetic field in an embodiment of the present application is provided.

[0084] Based on the magnetic field emitted by the magnetic dipole in FIG2 , as shown in FIG3 , a schematic diagram of the magnetic field emitted by a magnetic transmitter provided on a wearable device according to an embodiment of the present application is provided. Taking a structure in which a magnetic transmitter is provided in the middle of the wearable device and a magnetic receiver is provided at each of the left and right ends as an example, the following parameters are defined based on the magnetic field emitted by the magnetic transmitter provided on the wearable device in FIG3 and the spatial geometric structure information of the wearable device:

[0085] P1: the center point of the magnetic transmitter;

[0086] P2: Set the center point of the magnetic receiver on the left end of the wearable device;

[0087] P3: Set the center point of the magnetic receiver on the right side of the wearable device;

[0088] L1: perpendicular bisector (ray) of the magnetic transmitter;

[0089] L2: The line connecting the center point of the left magnetic receiver to the center point of the magnetic transmitter, that is, the line connecting P1 and P2;

[0090] L3: The line connecting the center point of the right magnetic receiver to the center point of the magnetic transmitter, that is, the line connecting P1 and P3;

[0091] L4: The tangent line passing through the center point of the coil in the average direction of the magnetic flux lines passing through the left end magnetic receiver;

[0092] L5: The tangent line passing through the center point of the coil in the average direction of the magnetic flux lines passing through the right end magnetic receiver;

[0093] L6: The perpendicular bisector (ray) of the plane where the Z axis of the left magnetic receiver is located, defined as the perpendicular bisector of the left magnetic receiver;

[0094] L7: The perpendicular bisector (ray) of the plane where the Z axis of the right receiving coil is located, defined as the perpendicular bisector of the right magnetic receiver;

[0095] L8: The line (line segment) connecting P2 to P3, which is defined as the distance between the two contact points of the user's head;

[0096] P4: intersection of L1 and L8;

[0097] α: The angle between L1 and L2, defined as the angle between the left magnetic receiver and the magnetic transmitter;

[0098] β: The angle between L1 and L3, defined as the angle between the right magnetic receiver and the magnetic transmitter;

[0099] θ: θ = α + β, defined as the “opening angle”;

[0100] γ: the angle between L4 and L6;

[0101] δ: the angle between L5 and L7.

[0102] Since the wearable device's dimensions are fixed, the only thing that changes is the bending angle. L2 and L3, the two chords of the ellipse surrounding the wearable device, have negligible length variations. Therefore, the lengths of L2 and L3 can be considered fixed. Since P1 is set in the center, L2 and L3 are equal. When worn by different users, only L8 and a series of angles (α / β / θ / γ / δ / …) change.

[0103] Taking a three-axis orthogonal receiving coil as an example, when the magnetic transmitter's coil is normally emitting an alternating magnetic field, multiple L8s are preset. Based on the wearable device's geometry, α and L8 have a one-to-one mapping, meaning one L8 length value corresponds to one α angle value. At this point, the induced voltages Ux, Uy, and Uz on the three orthogonal coils of the left-end magnetic receiver are read. Temporarily, P2 is considered the origin O(0,0,0). The direction vector of L4 is (Ux,Uy,Uz). Based on spatial analytic geometry, it can be determined that γ and α have a one-to-one mapping, and therefore, L8 and γ also have a one-to-one mapping relationship. Based on this, by changing the preset L8, a corresponding set of three-axis induced voltages is read on the left-end magnetic receiver, thereby establishing a corresponding relationship between the magnetic induction readings of the left-end magnetic receiver and the preset L8.

[0104] The same process is applied to the right magnetic receiver, thereby establishing a correspondence between the magnetic induction reading of the right magnetic receiver and the preset L8. Of course, it is also possible to simultaneously read the magnetic induction readings of the left and right magnetic receivers and establish a correspondence each time the size of L8 is changed. The specific implementation method is flexibly selected by those skilled in the art based on actual needs and is not specifically limited here.

[0105] In some embodiments of the present application, determining the distance between the two contact points on the user's head based on the current magnetic induction data of each magnetic receiver and the calibration correspondence includes: determining the distance between the two contact points on the user's head corresponding to the current magnetic induction data of each magnetic receiver and the calibration correspondence based on the current magnetic induction data of each magnetic receiver; and fusing the distances between the two contact points on the user's head corresponding to the current magnetic induction data of each magnetic receiver to obtain the final distance between the two contact points on the user's head.

[0106] Since differences in users' wearing styles may affect the magnetic receiver's induction of the magnetic field, the embodiment of the present application integrates the distance information between the two contact points on the user's head obtained based on the magnetic induction data of multiple magnetic sensors, thereby improving the accuracy of the distance calculation between the two contact points on the user's head.

[0107] The specific fusion strategy can be, for example, the method of finding the average value, or of course, the method of weighted average can be adopted according to the actual situation. The weight can be flexibly set according to the reliability of the magnetic induction data of multiple magnetic sensors. The higher the reliability, the larger the corresponding weight. The specific method of fusion can be flexibly set by those skilled in the art according to actual needs, and no specific limitation is made here.

[0108] In some embodiments of the present application, the wearable device is an arc-shaped structure, the magnetic transmitter is provided in the middle of the arc-shaped structure, and the first magnetic receiver and the second magnetic receiver are respectively provided at the two ends of the arc-shaped structure for contacting the user's head. The current magnetic induction data of each magnetic receiver includes the first magnetic induction data of the first magnetic receiver and the second magnetic induction data of the second magnetic receiver. Determining the distance between the two contact points on the user's head based on the current magnetic induction data of each magnetic receiver includes: determining a first relative angle between the magnetic transmitter and the first magnetic receiver based on the first magnetic induction data; determining a second relative angle between the magnetic transmitter and the second magnetic receiver based on the second magnetic induction data; and determining the distance between the two contact points on the user's head based on the first relative angle, the second relative angle, and the spatial geometric structure information of the wearable device.

[0109] As mentioned above, the wearable device of the embodiment of the present application can be a head-mounted device in the form of a headband, a headband, etc. In order to ensure the wearing effect, as shown in Figure 3 of the above embodiment, the wearable device can be designed as an arc-shaped structure, and a magnetic transmitter is provided in the middle of the arc-shaped structure, and a first magnetic receiver and a second magnetic receiver are respectively provided at both ends of the arc-shaped structure.

[0110] Based on the characteristics of the above-mentioned structural design, the embodiment of the present application provides another way to determine the distance between the two contact points on the user's head, that is, a real-time solution method. When the user wears the wearable device, the first magnetic receiver on the left end will output the first magnetic induction data, and the second magnetic receiver on the right end will output the second magnetic induction data. The first magnetic induction data and the second magnetic induction data are both induced voltages on a three-axis orthogonal coil. The first magnetic induction data corresponds to the direction vector of L4, and the second magnetic induction data corresponds to the direction vector of L5. Therefore, combined with the geometric structure information of the wearable device in Figure 3, the angle α of the left-end magnetic receiver, that is, the size of the first relative angle, and the angle β of the right-end magnetic receiver, that is, the size of the second relative angle, can be solved respectively.

[0111] After determining the sizes of the first relative angle α and the second relative angle β, we can further combine the spatial geometric structure of the wearable device and use trigonometric functions to solve the length of P2P3, that is, the distance between the two contact points on the user's head.

[0112] It should be noted that the embodiment of the present application is mainly based on a preferred embodiment of the spatial geometric structure design of the head-mounted device in the form of a headband for the location and number of the magnetic transmitter and the magnetic receiver. In this way, a magnetic transmitter is set in the middle of the wearable device, and a magnetic receiver is symmetrically set at both ends close to the back of the user's ear. On the one hand, the distance between the magnetic receivers set at both ends of the wearable device can more accurately reflect the width of the user's head. On the other hand, the symmetrical design is also easy to operate and implement, which improves the convenience of head measurement using wearable devices. Of course, those skilled in the art can also flexibly adjust the location and number of the magnetic transmitter and the magnetic receiver according to actual needs, which are not listed here one by one.

[0113] In some embodiments of the present application, determining the distance between the two contact points on the user's head based on the first relative angle, the second relative angle, and the spatial geometric structure information of the wearable device includes: determining the opening angle of the wearable device based on the first relative angle and the second relative angle; and determining the distance between the two contact points on the user's head using trigonometric functions based on the opening angle of the wearable device and the spatial geometric structure information of the wearable device.

[0114] After determining the magnitudes of the first relative angle α and the second relative angle β based on the aforementioned embodiment, the first relative angle α and the second relative angle β are added to obtain the current opening angle θ of the wearable device. Since L2 and L3 are the two chords of the ellipse in which the system is located, their length changes can be ignored, that is, the lengths are regarded as fixed values. Therefore, in the triangle formed by P1, P2, and P3, the length of the opposite side of the opening angle θ, that is, P2P3, can be solved using the law of cosines.

[0115] Of course, in addition to calculating in the above method, you can also use the cosine theorem to solve the length of the opposite side of the first relative angle α in the triangle formed by P1, P2, and P4, that is, the length of P2P4. In the triangle formed by P1, P3, and P4, you can use the cosine theorem to solve the length of the opposite side of the second relative angle β, that is, the length of P3P4. Finally, add the length of P2P4 to the length of P3P4 to get the length of P2P3.

[0116] To facilitate understanding of the various embodiments of the present application, a schematic diagram of a head measurement process in an embodiment of the present application is provided, as shown in Figure 4. The head measurement method in an embodiment of the present application is implemented based on a wearable device. The wearable device is provided with a magnetic transmitter and multiple magnetic receivers. When performing head measurement, the user is required to wear the wearable device, and when the two ends of the wearable device are in contact with the two contact points of the user's head, the magnetic transmitter is controlled to emit a magnetic signal to obtain the current magnetic induction data of each magnetic receiver.

[0117] After obtaining the current magnetic induction data of each magnetic receiver, different processing strategies can be used to determine the distance between the two contact points on the user's head based on the characteristics of the magnetic induction data and the spatial geometric structure characteristics of the wearable device. One strategy is to determine the distance between the two contact points on the current user's head based on the calibration correspondence between the magnetic induction data calibrated offline in advance and the distance between the two contact points on the user's head, and determine the distance between the two contact points corresponding to the magnetic induction data actually read based on the calibration correspondence. Another strategy is to determine the distance between the two contact points on the current user's head based on real-time calculation. This strategy requires the wearable device to be equipped with a magnetic receiver at both ends of the contact with the user's head. The relative angle between the magnetic transmitter and the two magnetic receivers is determined based on the magnetic induction data of the two magnetic receivers. Then, based on the relative angle and the spatial geometric structure information of the wearable device, the distance between the two contact points on the user's head is determined using trigonometric functions.

[0118] After determining the distance between the two contact points on the user's head based on the above strategy, combined with the wearing characteristics of the wearable device on the user's head, the distance between the two contact points on the user's head can reflect the width of the user's head. It can also be used to further calculate other dimensions of head size data. For example, the distance between the two contact points can be used as the diameter of a circle to calculate the circumference of the circle, and the circumference of the circle can be used as the user's head circumference.

[0119] The present application also provides a method for constructing a three-dimensional head model. FIG5 shows a flow chart of a method for constructing a three-dimensional head model according to the present application. The method for constructing a three-dimensional head model includes at least the following steps S510 to S530:

[0120] Step S510, obtaining the user's head size;

[0121] Step S520, determining key point information of the user's head according to the size of the user's head;

[0122] Step S530: Determine a three-dimensional head model of the user according to the head size of the user and the key point information of the head of the user; wherein the head size of the user is obtained based on any of the aforementioned head measurement methods.

[0123] After obtaining the user's head size, the embodiment of the present application can further determine the user's head key point information based on the user's head size data such as head width and head circumference. The head key point information here mainly includes the user's facial key points, such as nose, eyes, mouth and other facial feature points. Based on the current measurement, the head width, head circumference and other information can be obtained, and the facial distribution characteristics of the facial key points can be combined to roughly restore the position of the user's facial key points, and then further combined with the standard head three-dimensional model to generate the current user's head three-dimensional model.

[0124] The standard three-dimensional head model can be obtained based on, for example, a 3D MM or Flame model. The specific method of constructing the standard three-dimensional head model can be flexibly determined by those skilled in the art in combination with existing technologies and is not specifically limited here.

[0125] The present application also provides a wearable device adjustment method. FIG6 shows a flow chart of a wearable device adjustment method according to the present application. The wearable device adjustment method includes at least the following steps S610 to S630:

[0126] Step S610, obtaining the user's head size;

[0127] Step S620: determining a contact state between the wearable device and the user's head according to the size of the user's head;

[0128] Step S630: adjusting the opening angle of the wearable device according to the contact state between the wearable device and the user's head, so that the opening angle of the wearable device is adapted to the size of the user's head;

[0129] The user's head size is obtained based on any of the aforementioned head measurement methods.

[0130] In order to improve the wearing comfort of the user, after obtaining the user's head size, the embodiment of the present application can also determine the contact state between the wearable device and the user's head based on the currently measured head size. The contact state here mainly refers to the close contact state between the wearable device and the user's head. If it is worn too tightly, it will affect the user's comfort and thus affect the user's usage experience.

[0131] Specifically, it can be judged in combination with the distance between the two ends of the wearable device when it is not worn, that is, in a natural state. If the difference between the currently measured head width and the distance between the two ends when the wearable device is not worn is greater than a certain threshold, it means that the current wearable device is in tight contact with the user's head, which may cause discomfort to the user. Therefore, the opening angle of the wearable device can be appropriately adjusted to make the opening angle of the wearable device adapt to the size of the user's head, thereby improving the user's wearing comfort.

[0132] The present application also provides a head measurement device 700. The head measurement device 700 is applied to a wearable device. The wearable device is provided with a magnetic transmitter and a plurality of magnetic receivers. FIG7 shows a schematic diagram of the structure of the head measurement device in the present application. The head measurement device 700 includes:

[0133] A first acquiring unit 710 is configured to acquire current magnetic induction data of each magnetic receiver when both ends of the wearable device are in contact with two contact points on the user's head and the magnetic transmitter emits a magnetic signal;

[0134] A first determining unit 720 is configured to determine the distance between the two contact points of the user's head based on the current magnetic induction data of each magnetic receiver;

[0135] The second determining unit 730 is configured to determine the size of the user's head according to the distance between the two contact points on the user's head.

[0136] In some embodiments of the present application, the first determination unit 720 is specifically used to: obtain a calibrated correspondence between the magnetic induction data of each magnetic receiver and the distance between the two contact points on the user's head; and determine the distance between the two contact points on the user's head based on the current magnetic induction data of each magnetic receiver and the calibrated correspondence.

[0137] In some embodiments of the present application, the first determination unit 720 is specifically used to: adjust the opening angle of the wearable device according to multiple preset distances between two contact points of the user's head; obtain magnetic induction data of each magnetic receiver based on the opening angle of the wearable device; and construct the calibration correspondence relationship based on the magnetic induction data of each magnetic receiver and each preset distance based on the spatial geometric structure information of the wearable device.

[0138] In some embodiments of the present application, the first determination unit 720 is specifically used to: determine the distance between the two contact points on the user's head corresponding to the current magnetic induction data of each magnetic receiver and the calibration correspondence based on the current magnetic induction data of each magnetic receiver; and fuse the distances between the two contact points on the user's head corresponding to the current magnetic induction data of each magnetic receiver to obtain the final distance between the two contact points on the user's head.

[0139] In some embodiments of the present application, the wearable device is an arc-shaped structure, the magnetic transmitter is provided in the middle of the arc-shaped structure, and the first magnetic receiver and the second magnetic receiver are respectively provided at the two ends of the arc-shaped structure for contacting the user's head, and the current magnetic induction data of each magnetic receiver includes the first magnetic induction data of the first magnetic receiver and the second magnetic induction data of the second magnetic receiver. The first determination unit 720 is specifically used to: determine the first relative angle between the magnetic transmitter and the first magnetic receiver according to the first magnetic induction data; determine the second relative angle between the magnetic transmitter and the second magnetic receiver according to the second magnetic induction data; determine the distance between the two contact points on the user's head according to the first relative angle, the second relative angle and the spatial geometric structure information of the wearable device.

[0140] In some embodiments of the present application, the first determination unit 720 is specifically used to: determine the opening angle of the wearable device based on the first relative angle and the second relative angle; and determine the distance between the two contact points on the user's head using trigonometric functions based on the opening angle of the wearable device and the spatial geometric structure information of the wearable device.

[0141] It can be understood that the above-mentioned head measurement device can implement each step of the head measurement method provided in the above-mentioned embodiment. The relevant explanations about the head measurement method are applicable to the head measurement device and will not be repeated here.

[0142] The present application also provides a device 800 for constructing a three-dimensional head model. FIG8 shows a schematic diagram of the structure of the device 800 for constructing a three-dimensional head model according to the present application. The device 800 includes:

[0143] The second obtaining unit 810 is used to obtain the user's head size;

[0144] A third determining unit 820 is configured to determine key point information of the user's head according to the size of the user's head;

[0145] A fourth determining unit 830 is configured to determine a three-dimensional head model of the user according to the head size of the user and key point information of the user's head;

[0146] The user's head size is obtained based on any of the aforementioned head measurement methods.

[0147] The present application also provides an adjustment device 900 for a wearable device. FIG9 shows a schematic diagram of the structure of an adjustment device for a wearable device according to an embodiment of the present application. The adjustment device 900 for a wearable device includes:

[0148] The third obtaining unit 910 is used to obtain the user's head size;

[0149] a fifth determining unit 920, configured to determine a contact state between the wearable device and the user's head according to the size of the user's head;

[0150] a sixth determining unit 930, configured to adjust an opening angle of the wearable device according to a contact state between the wearable device and the user's head, so that the opening angle of the wearable device is adapted to a size of the user's head;

[0151] The user's head size is obtained based on any of the aforementioned head measurement methods.

[0152] An embodiment of the present application also provides a wearable device, comprising: a magnetic transmitter and multiple magnetic receivers; a processor; and a memory arranged to store computer-executable instructions, which, when executed, cause the processor to perform any of the aforementioned head measurement methods.

[0153] FIG10 is a schematic diagram of the structure of a wearable device according to an embodiment of the present application. Referring to FIG10 , at the hardware level, the wearable device includes a processor, and optionally also includes an internal bus, a network interface, and a memory. The memory may include a memory, such as a high-speed random access memory (RAM), and may also include a non-volatile memory (non-volatile memory), such as at least one disk storage device. Of course, the wearable device may also include hardware required for other services.

[0154] The processor, network interface, and memory can be interconnected via an internal bus, such as an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus, or an EISA (Extended Industry Standard Architecture) bus. These buses can be classified as address buses, data buses, and control buses. For ease of illustration, FIG10 shows only one bidirectional arrow, but this does not imply that there is only one bus or only one type of bus.

[0155] The memory is used to store programs. Specifically, the program may include program code, which includes computer operating instructions. The memory may include internal memory and non-volatile memory, and provides instructions and data to the processor.

[0156] The processor reads the corresponding computer program from the non-volatile memory into the internal memory and then runs it, forming a head measurement device at the logical level. The processor executes the program stored in the memory and is specifically used to perform the following operations:

[0157] When two ends of the wearable device are in contact with two contact points on the user's head and the magnetic transmitter emits a magnetic signal, obtaining current magnetic induction data of each magnetic receiver;

[0158] determining the distance between the two contact points on the user's head based on current magnetic induction data from each magnetic receiver;

[0159] The size of the user's head is determined according to the distance between the two contact points on the user's head.

[0160] The method performed by the head measurement device disclosed in the embodiment shown in FIG1 of the present application can be applied to or implemented by a processor. The processor may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the method can be performed by hardware integrated logic circuits in the processor or by software instructions. The processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. The methods, steps, and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in the embodiments of the present application can be directly implemented and executed by a hardware decoding processor, or by a combination of hardware and software modules in the decoding processor. The software module can be located in a storage medium well-known in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, etc. The storage medium is located in the memory, and the processor reads the information in the memory and, in conjunction with its hardware, completes the steps of the above method.

[0161] The wearable device can also execute the method executed by the head three-dimensional model construction device in Figure 5 or the method executed by the adjustment device of the wearable device in Figure 6, and realize the function of the head three-dimensional model construction device in the embodiment shown in Figure 5, or the function of the adjustment device of the wearable device in the embodiment shown in Figure 6. The embodiments of this application will not be repeated here.

[0162] The present application also provides a computer-readable storage medium that stores one or more programs. The one or more programs include instructions that, when executed by a wearable device including multiple application programs, enable the wearable device to perform the method performed by the head measurement device in the embodiment shown in FIG1 , and are specifically configured to perform:

[0163] When two ends of the wearable device are in contact with two contact points on the user's head and the magnetic transmitter emits a magnetic signal, obtaining current magnetic induction data of each magnetic receiver;

[0164] determining the distance between the two contact points on the user's head based on current magnetic induction data from each magnetic receiver;

[0165] The size of the user's head is determined according to the distance between the two contact points on the user's head.

[0166] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0167] The present invention is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0168] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a product including an instruction device that implements the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0169] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0170] In a typical configuration, a computing device includes one or more processors (CPUs), input / output interfaces, network interfaces, and memory.

[0171] Memory may include non-permanent storage in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. Memory is an example of a computer-readable medium.

[0172] Computer-readable media includes permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media (transitory media), such as modulated data signals and carrier waves.

[0173] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0174] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0175] The foregoing is merely an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A method for head measurement, wherein: The head measurement method is performed by a wearable device, the wearable device is provided with a magnetic transmitter and a plurality of magnetic receivers, and the head measurement method comprises: When two ends of the wearable device are in contact with two contact points on the user's head and the magnetic transmitter emits a magnetic signal, obtaining current magnetic induction data of each magnetic receiver; Determine the distance between the two contact points of the user's head according to the current magnetic induction data of each magnetic receiver; The size of the user's head is determined according to the distance between the two contact points on the user's head.

2. The head measurement method according to claim 1, wherein: Determining the distance between the two contact points of the user's head according to the current magnetic induction data of each magnetic receiver comprises: Obtaining a calibration correspondence between magnetic induction data of each magnetic receiver and the distance between two contact points on the user's head; The distance between the two contact points on the user's head is determined according to the current magnetic induction data of each magnetic receiver and the calibration correspondence.

3. The head measurement method according to claim 2, wherein: The obtaining of the calibration correspondence between the magnetic induction data of each magnetic receiver and the distance between the two contact points of the user's head includes: adjusting an opening angle of the wearable device according to a plurality of preset distances between two contact points on the user's head; Based on the opening angle of the wearable device, obtaining magnetic induction data of each magnetic receiver; Based on the spatial geometric structure information of the wearable device, the calibration correspondence is constructed according to the magnetic induction data of each magnetic receiver and each preset distance.

4. The head measurement method according to claim 2, wherein: The determining the distance between the two contact points of the user's head according to the current magnetic induction data of each magnetic receiver and the calibration correspondence includes: Determine, according to the current magnetic induction data of each magnetic receiver and the calibration correspondence, the distance between the two contact points on the user's head corresponding to the current magnetic induction data of each magnetic receiver; The distance between the two contact points on the user's head corresponding to the current magnetic induction data of each magnetic receiver is fused to obtain a final distance between the two contact points on the user's head.

5. The head measurement method according to claim 1, wherein: The wearable device is an arc-shaped structure, the magnetic transmitter is arranged in the middle of the arc-shaped structure, and the first magnetic receiver and the second magnetic receiver are arranged at two ends of the arc-shaped structure for contacting the user's head, respectively, and the current magnetic induction data of each magnetic receiver includes the first magnetic induction data of the first magnetic receiver and the second magnetic induction data of the second magnetic receiver. Determining the distance between the two contact points of the user's head according to the current magnetic induction data of each magnetic receiver comprises: determining a first relative angle between the magnetic transmitter and the first magnetic receiver according to the first magnetic induction data; determining a second relative angle between the magnetic transmitter and the second magnetic receiver according to the second magnetic induction data; The distance between the two contact points of the user's head is determined according to the first relative angle, the second relative angle, and the spatial geometric structure information of the wearable device.

6. The head measurement method according to claim 5, wherein: The determining, according to the first relative angle, the second relative angle, and the spatial geometric structure information of the wearable device, the distance between the two contact points of the user's head comprises: Determining an opening angle of the wearable device according to the first relative angle and the second relative angle; According to the opening angle of the wearable device and the spatial geometric structure information of the wearable device, a distance between two contact points of the user's head is determined by using a trigonometric function.

7. A method for constructing a three-dimensional head model, wherein: The method for constructing a three-dimensional head model comprises: Get the user's head size; Determine key point information of the user's head according to the size of the user's head; Determine the three-dimensional head model of the user according to the head size of the user and the key point information of the head of the user; Wherein, the head size of the user is obtained based on the head measurement method according to any one of claims 1 to 6.

8. A method for adjusting a wearable device, wherein: The adjustment method of the wearable device includes: Get the user's head size; Determining a contact state between the wearable device and the user's head according to the size of the user's head; Adjusting the opening angle of the wearable device according to the contact state between the wearable device and the user's head, so that the opening angle of the wearable device is adapted to the size of the user's head; Wherein, the head size of the user is obtained based on the head measurement method according to any one of claims 1 to 6.

9. A head measurement device, wherein: The head measurement device is applied to a wearable device, the wearable device is provided with a magnetic transmitter and a plurality of magnetic receivers, and the head measurement device comprises: A first acquisition unit is used to acquire current magnetic induction data of each magnetic receiver when two ends of the wearable device are in contact with two contact points of the user's head and the magnetic transmitter emits a magnetic signal; The first determining unit is used to determine the user according to the current magnetic induction data of each magnetic receiver. The distance between the two contact points on the head; The second determining unit is used to determine the size of the user's head according to the distance between the two contact points of the user's head.

10. A device for constructing a three-dimensional head model, wherein: The head three-dimensional model building device comprises: A second obtaining unit, used to obtain the user's head size; A third determining unit, configured to determine key point information of the user's head according to the size of the user's head; A fourth determining unit, configured to determine a three-dimensional head model of the user according to the head size of the user and key point information of the head of the user; Wherein, the head size of the user is obtained based on the head measurement method according to any one of claims 1 to 6.

11. An adjusting device for a wearable device, wherein: The adjustment device of the wearable device comprises: A third obtaining unit, used to obtain the user's head size; a fifth determining unit, configured to determine a contact state between the wearable device and the user's head according to a size of the user's head; a sixth determining unit, configured to adjust an opening angle of the wearable device according to a contact state between the wearable device and the user's head, so that the opening angle of the wearable device is adapted to a size of the user's head; Wherein, the head size of the user is obtained based on the head measurement method according to any one of claims 1 to 6.

12. A wearable device comprising: a magnetic transmitter and a plurality of magnetic receivers; processor; as well as A memory arranged to store computer executable instructions, wherein when the executable instructions are executed, the processor executes the head measurement method according to any one of claims 1 to 6, the head three-dimensional model construction method according to claim 7, or the wearable device adjustment method according to claim 8.

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