GB2611553A

GB2611553A - Facemask

Info

Publication number: GB2611553A
Application number: GB2114370.6A
Authority: GB
Inventors: Bednar Valerie; Perera Paul; Smith Gareth
Original assignee: My Maks Fit Ltd
Current assignee: My Maks Fit Ltd
Priority date: 2021-10-07
Filing date: 2021-10-07
Publication date: 2023-04-12
Also published as: GB2611553A8; GB202114370D0

Abstract

A method of selecting a facemask base 4 and an intermediate element 5 extending between the mask and the user’s face comprising: obtaining facial geometry, deriving parameters describing the facial geometry, comparing the parameters to parameters of a facemask bask, selecting a base according to the comparison, and determining a required geometry of the element based on the face and mask parameters. The base may be selected by determining that the face and base parameters are within a predetermined range. The facial geometry may comprise information regarding the user’s eyes, chin and nose and may be grouped into profiles which are used to select a base. Predetermined elements may be selected, or new elements created depending on the facial parameters. The element and mask may be manufactured and coupled together. The method may also comprise a test-fitting process whereby the fit of the mask is verified and the mask altered to improve the fit as needed.

Description

Facemask

FIELD AND BACKGROUND

[0001] The present invention is concerned with an improved facemask with an improved fit, for example for use in healthcare settings. The present invention is further concerned with methods for the design of an improved facemask and for the verification of the fit of an improved facemask when in use.

[0002] Standard medical or surgical respirators/face masks, or other facemasks, are typically placed over the mouth and nose of a user, to reduce or prevent the airborne transmission of pathogens to and from the user, often in the form of respiratory droplets or an aerosol. Respirators, also referred to as facemasks herein, like that conforming to local or international standards, like FFP2, FFP3 or N95, aim to create a substantially air tight seal between the mask and the face of the user in use, so as to prevent the transmission of airborne pathogens or particulates to and from the user.

[0003] Respirators, or facemasks, come in different shapes and sizes. However, variations in face shape and size across different users can be significant, and therefore some users find that respirators or facemasks, perhaps conforming to certain standards like FFP3 or other standards, do not fit adequately. That is to say, in a healthcare setting for example, the mask may not fit adequately to pass a mask fit test designed to ensure the mask fit satisfies certain criteria to protect the user and others in the healthcare setting.

[0004] Additionally, mask fit tests, like those carried out in hospitals or other healthcare settings for example, can be time consuming, labour intensive and resource intensive. Delays in mask fit tests can be due to sub-optimal facemasks being chosen for a user in the first place, the standard face mask not fitting the user due to the user's face size or shape, and/or the verification of fit process being time consuming.

[0005] In addition, poorly fitting facemasks can be uncomfortable for long periods of time.

In some cases, even if a facemask fits suitably, it may still be uncomfortable because of its shape, configuration or materials. In such cases, facemasks are more likely to be removed, thereby reducing their effectiveness.

[0006] The issues and difficulties of facemask fitting are conventionally addressed, and to some extent solved, using elastic and flexible materials that can accommodate a variety of face geometries and sizes. The masks use flexible, for example elastic strips, to stretch over the head and to bias the mask against the face. Such masks are very well used in a variety of applications. However, the recent pandemic of COVID-19 has shown that whilst these masks are a great improvement they can still allow some pathogens to pass and, particularly for healthcare professionals, is of great concern.

[0007] The inventors have devised an alternative approach not only to mask design but importantly to the way in which a mask is selected, fitted and additionally optimised thus providing significant improvements over existing technologies.

[0008] At least certain embodiments of the present disclosure address one or more of these problems as set out above. For example, the present inventors have established a way to more efficiently design and verify the fit of a facemask with an improved fit.

SUMMARY

[0009] Aspects of the invention are set out in the accompanying claims.

[0010] In accordance with the present disclosure, there is provided a method comprising obtaining face data of a user, processing the face data to determine one or more parameter values representative of one or more physical properties of the user's face, comparing one or more parameter values to one or more predetermined values associated with one or more candidate facemask bases, based on the comparison, identifying a facemask base of the one or more candidate facemask bases, and based on the face data and the identified facemask base, determining a required geometry of an intermediate element which, in use, extends between the identified candidate facemask base and the user's face.

[0011] According to the present disclosure a method, and also an associated apparatus, is provided which determines and optimises the creation of a bespoke mask in a series of steps. Specifically, the method involves identifying, for a specific user, a unique intermediate element that matches particular facial geometries with a range of predetermined candidate facemask components.

[0012] As described herein, such an arrangement not only provides for enhanced mask functionality and comfort but it also increases speed of manufacture and delivery and minimises waste material usage.

[0013] In some examples, the candidate facemask base is any standard medical or surgical or other respirator or facemask, which may conform to a recognised standard, for example the British Standards Institute, FFP2 which filters at least 94% of airborne particles, FFP3 which filters at least 99% of airborne particles or N95 which filters at least 95% of airborne particles, or any other standard. Alternatively, in some examples, the facemask base is a custom-made facemask or facemask base designed to receive an intermediate element, or any other facemask or facemask base.

[0014] Thus, in accordance with the present disclosure, a candidate facemask is identified and a geometry for an intermediate element is determined based on the physical properties of a user's face. Accordingly, a suitable facemask base and intermediate element is identified in a more efficient manner. Furthermore, the addition of the intermediate element with the facemask base reduces air leakage and thereby increases performance. The intermediate element geometry is based on the face data and the identified facemask base and so where a facemask base is used that conforms to a standard, the intermediate element may supplement deficiencies in the size or shape match between the user's face and the standard facemask base.

[0015] In some examples, the method further comprises outputting an indication of the required geometry of the intermediate element and an indication of the identified facemask base. This provides a simple indication to the user, allowing a user to quickly identify the required facemask base and intermediate element. This is especially useful in warehouse and manufacturing settings. In other examples, the precise geometry of the intermediate element may be output to the user to provide a bespoke intermediate element that may be manufactured to precise tolerances. Indeed, faces are commonly asymmetrical, and in conventional approaches symmetric masks have been used. However, the intermediate element of the present invention provides a bespoke fit that matches asymmetries of a user's face, thereby providing a better fitting mask and a mask with increased comfort. The intermediate element is bespoke to a user's unique facial geometries or disabilities. In some examples, the facemask base and/or the intermediate element may also be identified based on a respiratory condition or respiratory performance of the user. For example, a user with asthma may require a facemask base with a greater volume when secured against the face. The facemask base and/or the intermediate element therefore may also be identified based on a health condition of the user. Furthermore, a user may have facial hair that disrupts a seal between a conventional mask and the user's face, and so utilising an intermediate element according to the present invention that better corresponds with the profile of the user's face, accounting for a certain amount of compression of facial hair, may be provide an improved fit.

[0016] In some examples, the intermediate element is configured to provide an abutment interface between the identified facemask base and the face of the user in use. In this case, the intermediate element is a seal between the identified facemask base and the face of the user in use. This reduces a gap size between the user's face and the identified candidate facemask base and therefore reduces leakage in the seal between the facemask and the user's face. The intermediate element may be formed of a single unit or a single material.

[0017] Alternatively, the intermediate element may be modular. The intermediate element may be formed of plastic or a polycarbonate. Additionally or alternatively, the intermediate element may be formed by additive manufacturing. The intermediate element may be formed from a material with compressive properties. For example, the intermediate element may have predetermined compressive properties to apply a biasing force against the face. In some examples, the elastic/compressive properties of the intermediate element and facemask base may be chosen based on intended use. For example, where the greatest protection is required, a hard facemask base and intermediate element (low elasticity and can survive a high tensile load without experiencing plastic deformation) may be used to provide a high force when secured against the face of the user. Such cases may arise when dealing with extremely dangerous airborne particles or where use of the mask is short-lived. Alternatively, where comfort is more important, for example for increased length of use, materials which are more compressive may be used and the mask may be secured against the face with a lower force.

[0018] In some examples, identifying the facemask base is further based on determining a numerical closeness between the one or more predetermined values associated with the facemask base and the one or more parameter values. Numerical/numeric closeness is intended to refer to how close two numbers are in value. The parameter values and predetermined values may correspond with the same measurement of one or more physical properties of the user's face. In some examples, the facemask base with dimensions closest to the parameter values of the user's face may be identified. The predetermined values of the candidate facemask bases may be values that correspond to the parameter values of the user's face. The predetermined values may be calculated from previous experiment or measurement. In some examples, an average of two predetermined values are compared to two or more parameter values. In some examples, a weighted average is used.

[0019] Thus, the facemask base that represents the closest match to the user's face dimensions is identified, resulting in more efficient and automatic identification. The techniques of the present disclosure allow for the use of standard facemask bases, which may be mass produced and therefore cheaper than entirely custom facemask bases. Although, it will be appreciated that any facemask, for example surgical, medical, conforming to any standard or a custom made mask, may be utilised with the present invention as the facemask base.

[0020] In some examples, identifying the facemask base is further based on determining that the one or more parameter values are within a predetermined range of the one or more predetermined values associated with the facemask base. Accordingly, a facemask base that is a suitably close fit to the user's face may be identified, further increasing the efficiency of the fit process. Additionally, a greater range of facemask bases may be suitable for use with a user's face than if no predetermined range were used.

[0021] In some examples, the number of parameter values may be one. The inventors of the present application have determined that an eyes to chin distance of a user's face provides enough information to be able to identify a suitable facemask base, while reducing the amount of data measurement and processing. Alternatively, in some other examples the number of parameter values is two or three or more.

[0022] In some examples, the face data comprises nose information relating to one or more physical properties of the user's nose, and the identified facemask base is associated with one or more candidate intermediate elements. In some examples, determining the required geometry of the intermediate element comprises processing the face data to determine one or more profile values relating to the one or more physical properties of the user's nose, comparing the one or more profile values to one or more intermediate element profile values associated with the one or more candidate intermediate elements, and based on the comparison, identifying the required geometry of the intermediate element.

[0023] The profile values and intermediate element profile values may correspond with the same measurement of one or more physical properties of the user's nose. In some examples, the intermediate element profile values of the candidate intermediate elements are values that correspond to the profile values of the user's nose. The inventors of the present invention have determined that a user's nasal profile is a good indicator for the required geometry of an intermediate seal. In particular, the inventors of the present invention have determined that the dimensions and geometry of the bridge of the nose is a good indicator of the fit of a mask. Here, nose profile refers to one or more of, or a combination of, a nose length, nose width, nasal ridge length, nose protrusion length, nose angle, and the surrounding face area. Large variation exists between nose shape, size, angle of protrusion, and surrounding facial areas of users and so an intermediate element that complements the user's specific nasal profile provides an improved fit and seal of the facemask. In some examples, the intermediate element profile values have been calculated from previous experiment or measurement. In some examples, an average of three profile values are compared to an average of three intermediate element profile values. In some examples, a weighted average is used.

[0024] In some examples, identifying the required geometry of the intermediate element further comprises determining that the one or more profile values are within a second predetermined range of the one or more intermediate element profile values associated with one of the one or more candidate intermediate elements and selecting the geometry of the associated candidate intermediate element as the required geometry of the intermediate element. This example further comprises, as an alternative, based on determining that the one or more profile values are not within the second predetermined range of the one or more intermediate element profile values associated with one or more candidate intermediate elements, determining the required geometry of the intermediate element based on the one or more profile values.

[0025] Thus, the identified facemask base is associated with one or more candidate intermediate elements, and the intermediate element of these one or more candidate intermediate elements with intermediate element profile values that best match the profile values of the user's nose is identified. The inventors of the present invention have established that an intermediate element, which acts as seal element when combined with a facemask base provide improvements in facemask performance, in that the air leakage is reduced due to an improved fit, increased comfort, reduced waste as facemask bases that do not fit the user may be modified with an intermediate element to ensure a better fit. The techniques of this disclosure therefore provide a facemask with an improved fit, and a more efficient way of determining such a facemask.

[0026] Furthermore, where a user does not have one or more profile values that are within the second predetermined range of the one or more intermediate element profile values associated with one or more candidate intermediate elements, a geometry of a custom intermediate element is determined. Accordingly, the techniques of the present disclosure provide an intermediate element that fits a user's face even when the user's nasal profile is different from the assumed profile used in standard facemasks.

[0027] In some examples, the one or more profile values comprise one or more of the length, width, depth, or angle of the user's nose or nasal ridge or the size or shape of the user's nose. The inventors have determined that nasal profile measurements are indicative of the required geometry of an intermediate element to ensure a suitable fit.

[0028] In some examples, determining the required geometry of the intermediate element is further based on at least one of a predicted level of deformation of the identified facemask base, the intermediate element and the user's facemask when in use. Alternatively, the determining may be based on any combination of these. Furthermore, in some examples, the predicted level of deformation is based on an actual level of deformation that has been measured or in other examples, the predicted level of deformation is an actual level of deformation.

[0029] A good fit of a facemask is achieved when the seal between the facemask and the user's face is substantially airtight. By using a predicted or actual level of deformation of the identified facemask base, the intermediate element and the user's face, it is possible to ensure that a good fit is achieved, i.e. that the seal is substantially airtight. In some examples, the face is deformed slightly when the facemask is worn in use to ensure an airtight seal. In addition, the identified facemask base and/or the intermediate seal element may deform when a force is applied to them by a strap securing them in place on the user's face or by another force, such that basing the determination of the required geometry of the intermediate element on a predicted or measured or actual level of deformation provides an improved seal and fit to the face of the user. Here, a strap is a flexible, perhaps elastic, strip that stretches around the user's head and biases the mask against the face of the user in use.

[0030] In some examples, the method comprises manufacturing the intermediate element to the determined required geometry of the intermediate element or selecting a manufactured intermediate element with the determined required geometry of the intermediate element. The intermediate element may be manufactured using additive manufacturing techniques. The intermediate element may be moulded or formed using another suitable process that the person skilled in the art of manufacture would understand, for example the mask may be manufactured using a 5-axis machine. The intermediate element may be made of a polycarbonate. In some examples, the intermediate element is combined with the identified facemask base to form a composite facemask. The geometry of the intermediate element may be designed so as to enable the intermediate element to connect to the identified facemask base.

[0031] In some examples, the method further comprises verifying the fit of the composite facemask to the user's face. Thus, the fit may be verified to ensure that a suitable facemask base has been identified and that the determined geometry of the intermediate element is suitable, in that an adequate fit to the user's face has been achieved. Accordingly, the efficiency of the mask fit process is increased.

[0032] Verifying the fit of the composite facemask to the user's face may further comprise capturing interface data of the user's face and composite facemask when in use and, based on the interface data, determining a gap between a composite facemask and the user's face. The interface data is data of the user's face with the composite mask secured, like that in use. The interface data may be captured by a mobile computing device or camera or by a sensing device. The interface data may be captured by the same device as that captured the face data, or alternatively, it may be captured by a different device. Determining the gap may be performed by one or more artificial intelligence engines utilising neural network or machine learning techniques or image/video analysis techniques. Thus, the verification is automatic and can improve over time as more data is collected.

[0033] In some examples, verifying the fit of the composite facemask to the user's face is further based on determining whether one or more fit-quality measures are satisfied. The fit-quality measures may be based on mask fit criteria used in mask fit tests in healthcare settings. The fit-quality measures may be configurable and received as input from a user. Thus, it can be quickly determined whether the composite facemask is suitable for use in a healthcare setting without using significant resources and time.

[0034] In some examples, the method may further comprise in response to determining that one or more fit-quality measures are not satisfied, re-determining the required geometry of the intermediate element based on the captured interface data. Additionally or alternatively, the method may comprise re-identifying the facemask base. Thus, when a good fit has not been achieved, the system utilises a feedback loop to improve the fit until the fit-quality measures are satisfied. In some examples, regression analysis may be performed with reference to previous scan data to improve the mask fit detection.

[0035] The method may further comprise manufacturing the re-determined intermediate element. In some aspects, the re-determined intermediate element may be manufactured using additive manufacturing techniques. Accordingly, where additive manufacturing machinery is available, the intermediate element is available quickly for use.

[0036] The one or more fit-quality measures may comprise one of a maximum gap size between the user's face and the composite facemask, a maximum level of deformation of the composite facemask or a maximum level of deformation of the user's face. The inventors have determined that one or more of these fit-quality measures is indicative of how well the facemask fits to the user's face in use and therefore how effective the seal between the composite facemask and the user's face is and how well the facemask may protect the user.

[0037] The intermediate element may be configured to connect to a portion of the identified facemask base through one or more of an interference fit, an application of adhesive, and use of a mechanical coupling portion. The interference fit or mechanical coupling portion may be integral to the intermediate element. For example, the intermediate element may have a cross-section configured to connect to a periphery of the facemask base. In some examples, the cross-section is curved and has a receiving portion for receiving a periphery of the facemask base. The connection may be achieved through press fitting the facemask base into the receiving portion of the intermediate element, and it may remain connected through friction between the facemask base and intermediate element and the interference fit.

[0038] The intermediate element may be configured to provide a substantially airtight seal between the intermediate element and the identified facemask base and between the intermediate element and the face of the user in use.

[0039] The face data may be obtained by an imaging sensor of a mobile computing device.

The face data may be obtained by a camera of a mobile phone, for example by a smartphone, Apple's iPhone or Samsung's Galaxy range.

[0040] In some examples, the one or more candidate facemask bases are facemasks conforming to one or more recognised national or international standards. The identified facemask base may be a standard facemask. In the present disclosure, a standard facemask may refer to any facemask that conforms to one or more recognised standards, like a standard from BSI, FFP3, N95, FFP2, Type I, Type I R, Type II, Type II R, EN 14683, EN149:2001, ASTM, and/or NIOSH.

[0041] In some examples, the facemask base comprises one or more receiving portions for one or more air filters. In some examples, the facemask base comprises two or more receiving portions for air filters. One or more of the air filters may be reusable. In some examples, the facemask base comprises two or more receiving portions for a strap. In some examples, one or more of the facemask base and intermediate element is transparent.

[0042] In accordance with the present disclosure, there is provided a computer-readable medium comprising instructions, which when executed by one or more processors, cause the one or more processors to carry out any aspect of the present disclosure. In some examples, the computer-readable medium is a non-transitory computer-readable medium.

[0043] In accordance with the present disclosure, there is provided a system comprising one or more processors configured to perform the method of any aspect of the present disclosure.

[0044] In accordance with the present disclosure, there is provided a facemask comprising a facemask base, wherein the facemask base is selected from one or more candidate facemask bases based on a comparison of one or more parameter values determined from face data of a user to one or more predetermined values associated with the one or more candidate facemask bases, each of the one or more candidate facemask bases associated with one or more candidate intermediate elements, and an intermediate element corresponding to the user's face in use, wherein a geometry of the intermediate element is determined based on a comparison of one or more profile values determined from the face data to one or more intermediate element profile values associated with the one or more candidate intermediate elements.

[0045] According to a second aspect, there is provided a method comprising obtaining body part data of a user, wherein the body part data comprises geometric information of a user's body part, processing the body part data to determine one or more parameter values representative of one or more physical properties of the user's body part, comparing one or more parameter values to one or more predetermined values associated with a plurality of candidate elements, based on the comparison, identifying two or more elements of the plurality of candidate elements, and outputting identification of the identified two or more elements.

[0046] The methods according to the present disclosure may be implemented by a device, or a system of devices.

[0047] Other aspects will also become apparent upon review of the present disclosure, in particular upon review of the Brief Description of the Drawings, Detailed Description and Claims sections.

BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Examples of the disclosure will now be described, by way of example only, with reference to the accompanying drawings in which: [0049] Figure 1A shows a facemask base and Figure 1B shows a side profile view of the facemask base; [0050] Figure 2A shows an intermediate element and Figure 2B shows a cross-sectional view of the intermediate element; [0051] Figure 3A shows a combination of the facemask base and intermediate element and Figure 3B shows a side profile view of the composite facemask based and intermediate element; [0052] Figure 4A shows the composite facemask base and intermediate element in situ on a user's face, Figure 4B sows a side profile view of the composite facemask base and intermediate element on the user's face, and Figure 4C shows an alternative view of the composite facemask base and intermediate element in situ on the user's face; [0053] Figure 5A shows face data of a user's face, Figure 5B shows further face data, Figure 50 shows face data of a side profile of a user's face; [0054] Figure 6 shows a schematic of the facemask base identification and intermediate element identification according to the present disclosure; [0055] Figure 7 shows interface data of a user's face when combined when the composite facemask; and [0056] Figure 8 shows a method according to the present disclosure.

[0057] While the disclosure is susceptible to various modifications and alternative forms, specific example approaches are shown by way of example in the drawings and are herein described in detail. It should be understood however that the drawings and detailed description attached hereto are not intended to limit the disclosure to the particular form disclosed but rather the disclosure is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the claimed invention.

[0058] It will be recognised that the features of the above-described examples of the disclosure can conveniently and interchangeably be used in any suitable combination.

DETAILED DESCRIPTION

[0059] Figure 1A shows a facemask base 1. Facemask base 1 may include a portion for receiving an air filter 2, or multiple portions for receiving multiple air filters. Facemask base 1 may be a facemask conforming to a standard, for example FFP2, FFP3 or N95. Facemask base 1 may be a mass-produced facemask or it may be a custom-made facemask. Air filter 2 is configured to filter air passing through it to remove or reduce the airborne transmission of pathogens. Figure 1B shows a side profile view of the facemask base 1.

[0060] Figure 2A shows an intermediate element 3. Intermediate element 3 may be configured to connect to the facemask base and provide a seal between the facemask base and a user's face in use. Intermediate element 3 may be custom-made for the user's face or identified based on measurements of the user's face. Intermediate element 3 may be formed from a polycarbonate.

[0061] Figure 2B shows the cross-sectional view of the intermediate element 3 from Figure 2A through the cross-section A'. As shown in Figure 2B, the intermediate element 3 may have a curved cross-section. This enables the intermediate element 3 to be connected to the facemask base 3 through an interference fit. For example, the curved cross-section of the intermediate element 3 may be complementary to a peripheral lip of the facemask base 1.

[0062] Figure 3A shows a composite facemask 4, comprising a combination of the facemask base 1 and the intermediate element 3. As shown in this figure, the intermediate element 3 connects to the periphery of the facemask base 1 so as to form a seal between the composite facemask and the user's face when in use. Thus, through identification of a required facemask base and intermediate element, based on a user's face, a better fitting facemask can be identified. The composite facemask 4 thus provides a better seal between the user's face and the composite facemask in use than through the user of a facemask base without an intermediate element. Figure 3B shows a side profile view of the composite facemask 4.

[0063] Figure 4A shows the composite facemask 4 in situ on a user's face 5. When in use, the composite facemask base 4 is situated on the user's face 5 over the user's nose and mouth, overlapping the user's chin. The composite facemask 4 may be held in place by one or more straps that are placed around the user's head, thus securing the composite facemask 4 to the user's face 5 in use. Figure 4B shows a side profile view of the composite facemask 4 in situ on the user's face 5.

[0064] Figure 4C shows an alternative view of the composite facemask 4 comprising the facemask base 1 and intermediate element 3, in situ on the user's face 5. As shown in this figure, the facemask base 3 is transparent and is formed of a transparent material. The intermediate element 3 is connected to the circumferential periphery of the facemask base 1 by an interference fit caused by the cross-sectional shape of the intermediate element 3. As further shown in this figure, the intermediate element 3 has a thickness that varies along its length. The geometry of the intermediate element 3, including its thickness profile, is determined based on the user's face. Thus, the intermediate element 3 provides a better seal by having a geometry complementary to the user's face shape and size. Accordingly, where a gap or worse fit would be when using the facemask base 1 alone, the intermediate element 3 provides a seal.

[0065] Figure 5A shows a user's face 5 and obtained face data 6. Face data 6 may be obtained by an imaging device. Face data 6 includes a plurality of data points 7, each data point having an associated x, y, and z Cartesian coordinate. Thus, relative positions in 3-dimensional space can be determined between different data points 7. The face data 6 includes data points 7 that correspond to positions of features of the user's face, for example the eyes, mouth, chin, and nose. These data points 7 of the face data 6 may be determined using one or more of image analysis, coordinate analysis, machine learning, and neural network techniques.

[0066] As shown in Figure 5A, one or more parameter values A that represents a physical property of the user's face may be determined from the face data 6 and data points 7. In particular, the one or more parameter values A may be an eyes to chin distance the user's face, as shown in the figure. As the face data 6 includes data points 7 having 3-dimensional coordinates, the eyes to chin distance can be determined by a comparison of the coordinates between the data points lying on the eyes and the data points lying on the chin of the user. As further shown in figure 5A, a nose length B and nose width C may also be determined from the face data 6 and data points 7 in a similar way.

[0067] Figure 5B shows face data 6 and data points 7 on a user's face 5 in greater detail than Figure 5A. As shown in this figure, face data 6 includes a plurality of data points 7, indicated by white dots and connecting lines. From the face data 6, the distances as defined with reference to Figure 5A may be determined.

[0068] Figure 5C shows a side profile of a user's face 5. As shown in this figure, the nose protrusion length D can be determined from the face data 6. As the face data 6 includes data points 7 having 3-dimensional coordinates, a nose protrusion length D can be determined by a comparison of the 3-dimensional coordinates of data points lying on and around the user's nose. Similar techniques can be used to determine a nose ridge length E and a nose angle B. [0069] Figure 6 shows a schematic of the facemask base 1 and intermediate element 3 identification according to the present disclosure. Once face data 6 of a user has been obtained, the face data 6 is processed to determine one or more parameter values representative of one or more physical properties. For example, parameter value A from Figure 5A is determined by processing the face data 6 including the data points 7.

[0070] Parameter value A is representative of an eyes to chin distance of the user's face.

Parameter value A is then compared to one or more predetermined values associated with one or more candidate facemask bases. As shown in Figure 6, the left-most y-axis shows a range of predetermined values associated with candidate facemask bases 10, 11, and 12. Each of the candidate facemask bases 10, 11, and 12 has a predetermined range of predetermined values associated with it. Parameter value A is compared to the predetermined values of candidate facemask bases 10, 11, and 12, and candidate facemask base 10 is identified from the comparison. More specifically, facemask base 10 is identified based on a numerical closeness of its associated predetermined value and the parameter value A. In other words, parameter value A is within a predetermined range of the predetermined value associated with facemask base 10.

[0071] As shown in Figure 6, candidate facemask base 10 has three intermediate elements associated with it, intermediate elements 10.1, 10.2, and 10.3. These intermediate elements 10.1, 10.2, and 10.3 are specific to facemask base 10 in that they are configured to connect with facemask base 10 and have a complementary shape to that of facemask base 10. Although not shown, facemask bases 11 and 12 also have one or more intermediate elements associated with them. The number of intermediate elements associated with each facemask base may vary from one to more. Intermediate elements 10.1, 10.2, and 10.3 have differently sized and/or shaped geometries.

[0072] With reference to Figures 5A and 50, face data 6 also comprises information relating to one or more physical properties of the user's nose. For example, the nose length B, nose width C, nasal ridge length E, nose protrusion length D, and nose angle B. From one or more of B, C, D, E, and 9, one or more profile values may be determined. The inventors of the present application have determined that the profile of the user's nose and surrounding face area can be used to provide an indication of the intermediate element that will provide a good fit of the composite facemask to the user's face.

[0073] With reference to Figure 6, one or more profile values Y may be compared to one or intermediate element profile values associated with candidate intermediate elements 10.1, 10.2, and 10.3. One or more profile values Y may be calculated from an average of B, C, D, E and G from Figures 5A and 5C, a weighted average, or a mathematical formula. As shown in Figure 6, one or more profile values Y is determined to be within a predetermined range of the one or more intermediate profile values associated with candidate intermediate element 10.1. Subsequently, the geometry of candidate intermediate element 10.1 is selected as the required geometry of the intermediate element.

[0074] Should the one or more profile values Y not be within a predetermined range of any of the candidate intermediate elements associated with identified facemask base 10, the required geometry of the intermediate element is determined based on the one or more profile values Y. In this case, as the user's nasal profile is not similar enough to any of the candidate intermediate elements associated with the identified facemask base, a geometry of a custom-made intermediate element is determined based on the one or more profile values Y. [0075] Figure 7 shows interface data 8 of a user's face when the composite facemask is situated on the user's face in use. As part of a verification process, interface data 8 may be captured. The interface data 8 may be used to determine a gap between the composite facemask and the user's face. This may be determined through the use of image analysis, machine learning, and/or artificial intelligence techniques.

[0076] The verification may also comprise determining whether one or more fit-quality measures are satisfied. For example, the interface data 8 may comprise a plurality of data points having 3-dimensional Cartesian coordinates, in a similar way to the face data 6. The one or more fit-quality measures may be one of a maximum gap size between the user's face and the composite facemask, a maximum level of deformation of the composite facemask or a maximum level of deformation of the user's face. The determination of whether the one or more fit-quality measures are satisfied may be performed using image analysis, machine learning, and/or artificial intelligence techniques.

[0077] If the one or more fit-quality measures are not satisfied, the required geometry of the intermediate element may be re-determined based on the captured interface data 8. For example, the required geometry of the intermediate element may be modified based on interface data 8. For example, the profile of the intermediate element along its length may be modified to reduce a size of a gap between the user's face and composite facemask.

[0078] Figure 8 shows a method 800 according to the present disclosure. Step S801 comprises obtaining face data of a user. Step 5802 comprises processing the face data to determine one or more parameter values representative of one or more physical properties of the user's face. Step S803 comprises comparing one or more parameter values to one or more predetermined values associated with one or more candidate facemask bases. Step S804 comprises based on the comparison, identifying a facemask base of the one or more candidate facemask bases. Step 5805 comprises based on the face data and the identified facemask base, determining a required geometry of an intermediate element which, in use, extends between the identified candidate facemask base and the user's face.

Claims

CLAIMS: 1. A method comprising: obtaining face data of a user; processing the face data to determine one or more parameter values representative of one or more physical properties of the user's face; comparing one or more parameter values to one or more predetermined values associated with one or more candidate facemask bases; based on the comparison, identifying a facemask base of the one or more candidate facemask bases; and based on the face data and the identified facemask base, determining a required geometry of an intermediate element which, in use, extends between the identified candidate facemask base and the user's face.
2. The method according to claim 1, wherein the method further comprises outputting an indication of the required geometry of the intermediate element and an indication of the identified facemask base.
3. The method according to any preceding claim, wherein the intermediate element is configured to provide an abutment interface between the identified facemask base and the face of the user in use.
4. The method according to any preceding claim, wherein identifying the facemask base is further based on determining a numerical closeness between the one or more predetermined values associated with the facemask base and the one or more parameter values.
5. The method according to claim 4, wherein identifying the facemask base is further based on determining that the one or more parameter values are within a predetermined range of the one or more predetermined values associated with the facemask base.
6. The method according to any preceding claim, wherein the face data comprises eye and chin information of the user's eyes and chin, and the one or more parameter values is selected from one or more of a distance between the eyes and chin of the user and the distance between nose and chin of the user.
7. The method according to any preceding claim, wherein the face data comprises nose information relating to one or more physical properties of the user's nose, and wherein the identified facemask base is associated with one or more candidate intermediate elements, and wherein determining the required geometry of the intermediate element comprises: processing the face data to determine one or more profile values relating to the one or more physical properties of the user's nose; comparing the one or more profile values to one or more intermediate element profile values associated with the one or more candidate intermediate elements; and based on the comparison, identifying the required geometry of the intermediate element.
8. The method according to claim 7, wherein identifying the required geometry of the intermediate element further comprises: determining that the one or more profile values are within a second predetermined range of the one or more intermediate element profile values associated with one of the one or more candidate intermediate elements and selecting the geometry of the associated candidate intermediate element as the required geometry of the intermediate element; or based on determining that the one or more profile values are not within the second predetermined range of the one or more intermediate element profile values associated with one or more candidate intermediate elements, determining the required geometry of the intermediate element based on the one or more profile values.
9. The method according to claims 7 to 8, wherein the one or more profile values comprise one or more of: the length, width, depth, or angle of the user's nose or nasal ridge or the size or shape of the user's nose
10. The method according to any preceding claim, wherein determining the required geometry of the intermediate element is further based on at least one of a predicted level of deformation of the identified face mask base, the intermediate element and the user's face when in use.
11. The method according to any preceding claim, wherein the method further comprises: manufacturing the intermediate element to the determined required geometry of the intermediate element or selecting a manufactured intermediate element with the determined required geometry of the intermediate element; and combining the intermediate element with the identified facemask base to form a composite facemask.
12. The method according to claim 11, wherein the method further comprises: verifying the fit of the composite facemask to the user's face.
13. The method according to claim 12, wherein verifying the fit of the composite facemask to the user's face further comprises: capturing interface data of the user's face and composite facemask when in use; and based on the interface data, determining a gap between the composite facemask and the user's face.
14. The method according to claim 13, wherein verifying the fit of the composite facemask to the user's face is further based on: determining whether one or more fit-quality measures are satisfied.
15. The method according to claim 14, wherein the method further comprises: in response to determining that one or more fit-quality measures are not satisfied, redetermining the required geometry of the intermediate element based on the captured interface data.
16. The method according to claim 15, wherein the method further comprises: manufacturing the re-determined intermediate element.
17. The method according to any one of claims 14 to 15, wherein the one or more fit-quality measures comprises one of a maximum gap size between the user's face and the composite facemask, a maximum level of deformation of the composite facemask or a maximum level of deformation of the user's face.
18. The method according to any preceding claim, wherein the intermediate element is configured to connect to a portion of the identified facemask base through one or more of an interference fit, application of adhesive, and use of a mechanical coupling portion.
19. The method according to any preceding claim, wherein the intermediate element is configured in use to provide a substantially air tight seal between the intermediate element and the identified facemask base and between the intermediate element and the face of the user in use.
20. The method according to any preceding claim, wherein the face data is obtained by an imaging sensor of a mobile computing device.
21. The method according to any preceding claim, wherein the identified facemask base is a standard facemask and optionally wherein the facemask base comprises one or more receiving portions for one or more air filters.
22. A computer-readable medium comprising instructions which, when executed by one or more processors, cause the one or more processors to carry out the method of any of claims 1 to 21.
23. A system comprising one or more processors configured to perform the method of any of claims 1 to 22.
24. A facemask, comprising: a facemask base, wherein the facemask base is selected from one or more candidate facemask bases based on a comparison of one or more parameter values determined from face data of a user to one or more predetermined values associated with the one or more candidate facemask bases, each of the one or more candidate facemask bases associated with one or more candidate intermediate elements; and an intermediate element corresponding to the user's face in use, wherein a geometry of the intermediate element is determined based on a comparison of one or more profile values determined from the face data to one or more intermediate element profile values associated with the one or more candidate intermediate elements.
25. A method comprising: obtaining body part data of a user, wherein the body part data comprises geometric information of a user's body part; processing the body part data to determine one or more parameter values representative of one or more physical properties of the user's body part; comparing one or more parameter values to one or more predetermined values associated with a plurality of candidate elements; based on the comparison, identifying two or more elements of the plurality of candidate elements; and outputting an indication of the identified two or more elements.