Facemask adaptor

Abstract

A method of manufacturing a facemask adaptor 4 is provided. The method comprises: scanning a user’s face to generate facial data; generating a model of the user’s face using this data; overlaying the

Description

FIELD OF THE INVENTION The present invention relates to facemask adaptor and a method of manufacturing the same. Particularly, the present invention relates to a facemask adaptor and a method of manufacturing a facemask adaptor for a Continuous Positive Airway Pressure facemask. BACKGROUND Commercial-off-the-shelf (COTS) facemasks, for example those used in the supply of oxygen to a hospital patient or an emergency services worker operating in an oxygen-deprived environment, are typically mass-produced and come in a limited number of sizes. There are a number of different types of facemask. Where a user has an abnormally shaped face, for example through injury or disease, facemasks do not form a good seal with the user’s face. To mitigate this, items such as dressings, gel packs, and towels are inserted between the facemask and the user’s face. These malleable structures fill in any gaps caused by depressions in the user’s face, and provide a relatively uniform surface onto which to place the facemask. Due to discomfort, facial sores / ulcers and air leakage even with these solutions in place, it has been found that facemasks are not being worn by users when required. Moreover, these solutions are difficult to apply, and need to be reshaped every time the facemask is removed. There is therefore a need for a more comfortable, robust and effective adaptor for face masks. SUMMARY OF THE INVENTION According to a first aspect, there is provided a method of manufacturing a facemask adaptor, the method comprising: scanning a user’s face to generate facial data; generating a model of the user’s face using the facial data; overlaying the model of the user’s face and a stored predetermined shape, the shape of the facemask adaptor being defined by the shape of the void between the model of the user’s face and the stored predetermined shape; and printing a facemask adaptor having the defined shape. Advantageously, the method produces a facemask adaptor which is comfortable for the user to wear and provides an effective seal between the user’s face and the face mask. Further, the solution may be implemented by non-medical professionals. The method may comprise extruding a planar surface away from the stored predetermined shape in the direction of the overlaid model of the user’s face, and extruding a planar surface away from the model of the user’s face in the direction of the overlaid predetermined shape, and aligning the two planar surfaces to form the void between the model of the user’s face and the predetermined shape. The predetermined shape may be the shape of an ideal face, that being a face of standard proportions without any abnormality. The method may comprise scanning a mannequin to generate template data, and generating a model of the mannequin using the template data to provide the predetermined shape. The predetermined shape may be the shape of the rear surface of a facemask, the rear surface being that surface that faces towards the user’s face. The method may comprise scanning the rear surface of a facemask to generate template data, and generating a model of the rear surface of the facemask using the template data to provide the predetermined shape. The facemask adaptor may be for use with a Continuous Positive Airway Pressure facemask. Scanning may comprise capturing an image using a mobile device. Scanning may comprise transmitting at least one laser beam towards the user’s face and recording the intensity and / or time of flight of the reflected beam. Scanning may comprise calculating depth information. Printing the facemask adaptor may comprise forming the facemask adaptor from silicone. Printing the facemask adaptor may comprise forming the facemask adaptor using additive layer manufacturing. Alternatively, printing may comprise moulding or cutting a material. According to a second aspect, there is provided a facemask adaptor obtained by the method according to any one of the preceding claims. BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the invention will now be described by way of example only with reference to the figures, in which: Figure 1 is a side view of a user wearing a face mask and face mask adaptor according to embodiments; and Figure 2 is a flow chart showing the method steps for manufacturing a facemask adaptor according to embodiments. DETAILED DESCRIPTION Embodiments generally relate to a method of manufacturing a facemask adaptor, to assist users with abnormally-shaped faces that do not result in a good seal between their face and the facemask. The resulting facemask adaptor tends to be more comfortable for the user and more effective (i.e. less prone to leaking) than existing solutions. The method generally comprises scanning a user’s face using a 3D scanner to generate facial data, comparing that facial data with a predefined shape (e.g. the shape of the rear of the facemask or the shape of an ideal face), and using the comparison to design and build a bespoke structure for the user to wear between the facemask and their face. A user 1 wearing a facemask on their face is illustrated in Figure 1. The facemask includes at least one strap 5. Two straps 5 are illustrated, but it would be appreciated the facemask could be secured with one strap, or more than two straps. The strap 5 may be elasticated. Alternatively, the strap 5 may include a clasp or other attachment mechanism. The strap 5 is used to secure a cup 2 to the user’s face. The cup 2 allows an oxygen-rich environment to be maintained around the user’s nose and mouth, thereby aiding their breathing. In other words, the cup 2 encloses the user’s nose and mouth. In an alternative embodiment, the cup 2 may enclose only the user’s nose. In an alternative embodiment again, the cup 2 may enclose the whole front side of the user’s face, including the eyes, nose and mouth. The cup 2 is provided with an inlet 3 through which oxygen is provided to the cup 2. The inlet 3 may also serve an outlet that allows carbon dioxide to leave the cup 2. Alternatively, a separate outlet may be provided. The inlet and / or outlet may be coupled to a ventilation system. The ventilation system may be part of a Continuous Positive Airway Pressure (CPAP) machine, and therefore the facemask may be a CPAP facemask. CPAP machines are a form of non-invasive ventilation, used for the long-term treatment of patients suffering with Obstructive Sleep Apnoea (OSA). Preferably, the cup 2, inlet 3 and strap 5 define a COTS facemask according to the prior art. To ensure an airtight seal between the facemask and the user’s face, an adaptor 4 is disposed between the cup 2 and the user’s face. The adaptor 4 is not integrated with the cup 2. The adaptor 4 is secured in place by the strap 5 pulling the cup 2 against the adaptor 4. The adaptor 4 is made of a resiliently deformable material, able to maintain its original form. The adaptor 4 may be made of rubber, neoprene or latex. The adaptor 4 is preferably made of silicone. The adaptor 4 is additively manufactured (i.e. 3D-printed). This adaptor 4 effectively fills in the facial contours of the user 1, providing the COTS facemask with the ‘ideal’ face (i.e. a facial shape with standard contouring, within a set of bounds) with which to form a seal. The adaptor 4 is a “second skin” that sits between the facemask and the face itself, it is not an addition or alteration to the existing COTS facemask. The adaptor 4 also tends to distribute pressure across the patient’s face, reducing the risk of pressure sores and discomfort. This is achieved by the adaptor 4 covering a larger surface area of the user’s face than the cup 2 otherwise would if fitted directly to the face. A process for manufacturing the adaptor 4 will now be described with reference to Figure 2. It should be noted that certain of the process steps depicted in the flowchart of Figure 2 and described below may be omitted or such process steps may be performed in differing order to that presented above and shown in Figure 2. Furthermore, although all the process steps have, for convenience and ease of understanding, been depicted as discrete temporally-sequential steps, nevertheless some of the process steps may in fact be performed simultaneously or at least overlapping to some extent temporally. Furthermore, the process steps may be performed continuously. In a first step 20, the user’s face is scanned to produce facial data. This scanning maps craniofacial anomalies in the user’s face. Preferably, the user’s face is scanned using a scanner. Here “scanning” means to capture 3D (three-dimensional) geometry and contours of a physical object such that the object can be digitally reproduced. The scanner is preferably a handheld scanner. The scanner may be a laser scanner. The laser scanner may be used to transmit a laser beam towards an object, and record the reflected laser beam. The differences in time of flight of the laser beam across different parts of the face can be used to calculate the distance from those parts of the face to the handheld scanner, and therefore the depth of facial features can be recorded. The intensity of the reflected laser beam may also be recorded to calculate the depth of the object being scanned. The scanner may alternatively be an optical camera connected to a controller; in other words, the scanner may be a user’s mobile phone or laptop computer. The scanner comprises a memory for storing data points that together than be used to digitally reconstruct the user’s face. The memory may be a non-volatile memory such as read only memory (ROM), a hard disk drive (HDD) or a solid state drive (SSD). The memory stores, amongst other things, an operating system and a software applications. The operating system may contain code which, when executed by the controller in conjunction with Random Access Memory, controls operation of each of hardware components of the scanner. The scanner may comprise a transmitter for transmitting the facial data to a server. For example, the transmitter may be a Wi-Fi® transmitter, Bluetooth® transmitter, or a 4g, 5g or 6g telecommunications standard transmitter. The controller may take any suitable form. For instance, it may be a microcontroller, plural microcontrollers, a processor, or plural processors. The first step 20 may be performed by the intended user 1 of the facemask. The facial data is transmitted to a server for processing after the user’s face has been scanned. In a second step 22, the scanner is used to scan a mannequin having a typical face without injury or abnormality to produce template data. In an alternative embodiment, the reverse side of the cup 2 of a COTS facemask is scanned to produce template data. This step may only be performed once, with the generated template data being stored in a database for use multiple times in the production of adaptors 4 for different users 1. Instead of using the scanner used in the first step 20, the scanning in the second step 22 may be performed using industrial equipment in a factory. In other words, the second step 22 may not be performed by the intended user 1 of the facemask. The template data is transmitted to a server for processing after the face has been scanned. The facial data and template data are processed, in a third step 24, using software to provide calibration and triangulation, and therefore to effectively “clean up” the data. Modelling software is used to convert the data into a digital model of the user’s face and a digital model of the rear of the facemask or the mannequin face (i.e. template models). The digital models are 3D models. The two digital models are then married up to produce a digital model of an adaptor 4. The adaptor 4 fills the gap between the two models (i.e. the model of the user’s face and the template model). In other words, the model of the user’s face and the model of the reverse side of the cup 2 or the model of the ideal face are overlaid (i.e. put next to each other). In one embodiment, a virtual structure is constructed on top of the template model, extruding a flat surface on the rear of the cup 2 (i.e. the side facing the user’s face). A virtual structure is constructed on top of the facial model, extruding a flat surface on the front of the facial model. The two flat surfaces are then aligned, such that the flat surfaces are co-planar. The two summed virtual structures define the virtual adaptor. In another embodiment, the virtual gaps between the facial model and the template model are filled, with the fill defining the virtual adaptor 4. The adaptor 4 geometry is defined by the negative, or space between the facial model and the template model. In a fourth step 26, a real adaptor 4 is constructed using the processed scan data. The adaptor 4 is formed to be the same shape as the virtual adaptor. The adaptor 4 is constructed using additive manufacturing, such as 3D printing. In an alternative embodiment, the 3D scan data is used to make a physical mould, rather than a digital mould. The physical mould may be produced using additive manufacturing. This mould is then filled with a medical grade material which sets to create the negative (i.e. the adaptor 4) physically, rather than digitally. In an alternative embodiment again, the adaptor 4 may be made by cutting away a larger block of material. The adaptor 4 is then sent to the user 1. In other words, the adaptor 4 is shipped to the user 1. In a final step 28, the user 1 applies the facemask by putting the strap(s) 5 over their head. The adaptor 4 is inserted between the cup 2 of the facemask and the user’s face. In an alternative embodiment, a deformable putty is used to produce a physical template adaptor. The putty is applied to the user’s face and a cup 2 pushed into it such that there are no gaps between the putty and the rim of the cup 2 (i.e. between the putty and the facemask) or between the putty and the user’s face. In other words, the user’s craniofacial abnormalities are filled to produce an ideal facial shape. The cup 2 is then removed and putty is then allowed to dry and solidify. The solidified putty is then scanned with the scanner such that the template adaptor is produced digitally. The adaptor 4 is then manufactured, for example using Additive Layer Manufacture, according to the template. Alternatively, a mould may be manufactured (e.g. using Additive Layer Manufacture) using the template adaptor i.e. the template adaptor forms the negative space within the mould. The physical mould may then be filled with medical-grade material such as silicone which sets to form the adaptor 4. Singular references do not exclude a plurality; thus, references to ‘a’, ‘an’, ‘first’, ‘second’, etc. do not preclude a plurality. In the claims, the terms “comprising” or “including” do not exclude the presence of other elements. Where, in the foregoing description, integers or elements are mentioned that have known, obvious, or foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the present disclosure, which should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that integers or features of the disclosure that are described as optional do not limit the scope of the independent claims. Moreover, it is to be understood that such optional integers or features, while of possible benefit in some embodiments of the disclosure, may not be desirable, and can therefore be absent, in other embodiments.

Claims

1. A method of manufacturing a facemask adaptor, the method comprising: scanning a user’s face to generate facial data;generating a model of the user’s face using the facial data;overlaying the model of the user’s face and a stored predetermined shape, the shape of the facemask adaptor being defined by the shape of the void between the model of the user’s face and the stored predetermined shape; andprinting a facemask adaptor having the defined shape.

2. The method according to claim 1, comprising extruding a planar surface away from the stored predetermined shape in the direction of the overlaid model of the user’s face, and extruding a planar surface away from the model of the user’s face in the direction of the overlaid predetermined shape, and aligning the two planar surfaces to form the void between the model of the user’s face and the predetermined shape.

3. The method according to claim 1 or claim 2, wherein the predetermined shape is the shape of an ideal face, that being a face of standard proportions without any abnormality.

4. The method according to claim 3, comprising scanning a mannequin to generate template data, and generating a model of the mannequin using the template data to provide the predetermined shape.

5. The method according to claim 1 or claim 2, wherein the predetermined shape is the shape of the rear surface of a facemask, the rear surface being that surface that faces towards the user’s face.

6. The method according to claim 5, comprising scanning the rear surface of a facemask to generate template data, and generating a model of the rear surface of the facemask using the template data to provide the predetermined shape.

7. The method according to any one of the preceding claims, wherein the facemask adaptor is for use with a Continuous Positive Airway Pressure facemask.

8. The method according to any one of the preceding claims, wherein scanning comprises capturing an image using a mobile device.

9. The method according to any one of the preceding claims, wherein scanning comprises calculating depth information.

10. The method according to any one of the preceding claims, wherein scanning comprises transmitting at least one laser beam towards the user’s face and recording the intensity and / or time of flight of the reflected beam.

11. The method according to any one of the preceding claims, wherein printing the facemask adaptor comprises forming the facemask adaptor from silicone.

12. The method according to any one of the preceding claims, wherein printing the facemask adaptor comprises forming the facemask adaptor using additive layer manufacturing.

13. A facemask adaptor obtained by the method according to any one of the preceding claims.

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