This application claims benefit of Sri Lankan priority application number LK/P/21608 filed on 12 ^th February, 2021.

FIELD OF THE INVENTION

[0001] The present invention relates to a face mask, and more particularly to a smart respiratory face mask capable of being worn by user for detection of respiratory parameters and other mask characteristics.

BACKGROUND OF THE INVENTION

[0002] In recent times, air pollution has become an increasing threat to humans due to industrialization and deforestation, resulting in increasing cases of human respiratory illnesses, pollution related complications of cardiovascular conditions, and conditions related to the organs, increasing health care costs.

[0003] Apart from the air pollution, the world is facing unprecedented threats from various microbes, especially from SARS-CoV-2 virus. The virus has serious ill effects on the respiratory system of the human body.

[0004] The inhalation of air contaminated by the harmful virus and/or other micro- organisms is a common route for infection of human beings. Further, the air exhaled by infected patients is also a source of contamination.

[0005] Respiratory masks or face masks incorporating a suitable filter material are considered to be ideal for use as a barrier to prevent species-to-species transmission of viruses, and also a barrier of entry of pollutants in human body. [0006] Further, these respiratory masks with the filter material are being used to protect wearer from inhaling pollutants and microorganisms or viruses, or to prevent the wearer from spreading germs/diseases when exhaling, coughing, and sneezing. [0007] During the pandemic time, wearing a respiratory mask in daily life is becoming a norm in most parts of the world.

[0008] Understandably, researchers all over the world are trying to work on various aspects of masks.

[0009] One such invention is disclosed in WIPO patent application with publication number 2011026515.

[0010] The said application discloses a face mask including a filter segment adapted to cover the mouth and nostrils of a user. The face mask further includes a support segment adapted for dismountable placement around the head of the user, and adapted to align the filter segment. The said mask restricts viruses or other microorganisms and pollutants from entering the body of the user.

[0011] Although, the said mask as disclosed in the WIPO patent application, may protect the user from various viruses and pollutants from entering the body of the user, however, these masks are not capable of detecting the respiratory characteristics of the user wearing these masks.

[0012] Another invention on masks is disclosed in the European patent application with publication number 3124083.

[0013] The said application discloses a smart mask that includes a front mask body, a main mask body, and fixing straps. The front mask body is disposed at a first opening end of the main mask body. The said front mask body is internally provided with a filter to absorb a pollutant. The mask body further includes a sensor configured to record a wearing time of the smart mask. Further, the fixing straps are configured to fix the smart mask over the nose and mouth.

[0014] However, the mask as disclosed in the European patent application 3124083, includes a built-in sensor, that makes the said sensor incapable of integrating detachably to the said mask, and does not allow the sensor to attach with the other masks available in the market. Further, the said mask does not allow the user to detect unusual breathing patterns related to contagious or chronic respiratory issues. [0015] Although, the sensor as disclosed in the said European application, records the wearing time of the said smart mask, however, this feature of recording the wearing time does not provide ulterior protection to the user wearing the said mask.

[0016] Therefore, there is a need to develop a smart respiratory mask sufficient to provide ulterior protection to the user. More specifically, there is a need for a smart mask with a detachable sensor, capable of monitoring, detecting, and displaying the user’s respiratory parameters such as respirator} _' rate, and mask characteristics such as mask fit, and mask saturation.

[0017] Further, there is a need to develop a smart respirator}' mask that may monitor, detect, and display respiratory parameters and mask characteristics by using a single sensing element.

[0018] Further, there is a need for a sensing element that is extremely sensitive to moisture absorption and desorption characteristics. Furthermore, a sensing element for a face mask is needed that reduces the response time for detecting breathing patterns.

[0019] In addition, there is a need to develop a smart respiratory mask capable of being worn by the user for long hours and enabling free activity of the jaw.

[0020] In nutshell, a smart mask is required which may overcome the above- discussed drawbacks and provide easy to operate and cost-effective mask.

SUMMARY OF THE INVENTION Technical Problem

[0021] An objective of the present invention is to provide a smart respiratory mask sufficient to provide ulterior protection to the user. [0022] Another objective of the invention is to provide a smart mask with a detachable sensor, capable of monitoring, detecting, and displaying the user’s respiratory parameters such as respiratory rate, and mask characteristics such as mask fit, and mask saturation. [0023] Another objective of the present invention is to develop a smart respiratory mask capable of being worn by the user for long hours and enabling free activity of the jaw. Yet another objective is to have a smart mask which may overcome the above-discussed drawbacks and provide easy to operate and cost-effective mask.

Technical Solution

[0024] In an aspect of the present invention, to overcome the above discussed problems, a smart respiratory face mask is disclosed. More specifically, the smart face mask is capable of being worn by a user for detection of respiratory parameters and other mask characteristics, such as respiratory rate, mask fit, and mask saturation is disclosed.

[0025] In an embodiment of the present invention, the said smart respiratory face mask includes an antimicrobial textile substrate adapted to be wrapped around the user’s respiratory orifices. The said textile substrate is adapted to restrict microbes and particulate matter from entering inside the body of the user.

[0026] In one embodiment of the present invention, the said smart respiratory mask further includes a sensor device detachably connected to the said substrate.

[0027] In an embodiment, the said sensor device includes an inner housing and outer housing.

[0028] In the said embodiment of the present invention, the said inner housing includes a first inner plastic mount, and a first outer plastic mount adapted to be aligned with the said first inner plastic mount. The said inner housing further includes an inner coupling element.

[0029] In one embodiment of the present invention, the said outer housing includes a second inner plastic mount, and a second outer plastic mount adapted to align with the second inner plastic mount. The said outer housing further includes an outer coupling element. [0030] In the said embodiment of the present invention, the said outer coupling element is adapted to detachably attach with the said inner coupling element, thereby enabling the said sensor device to be either attachable or detachable to the said textile substrate.

[0031] In one embodiment of the present invention, the said sensor device further includes a relative humidity (RH) sensing element made by printing a reduced graphene oxide (rGO) ink on a flexible printed circuit board substrate or other substrates.

[0032] In the said embodiment of the present invention, the said ink includes a reduced graphene oxide (rGO) amount of 70-99.9 wt% doped with at least one metal oxide loading of 0.1-30 wt%.

[0033] Specifically, the said ink includes chemical elements including carbon (C), tin (Sn), oxygen(O) in an atomic ratio of 1.0: 0.05-0.3: 0.1-0.7, respectively.

[0034] The said ink is adapted to adsorb and desorb moisture for sensing the breathing pattern of the user based on the said adsorption and desorption of the moisture.

[0035] In one embodiment of the present invention, the said mask further includes a data processing module operatively coupled with a communication module which is attached to the said sensing element, and the said communication module is configured to the said PCB substrate. The said data processing module is adapted to compute the sensed breathing pattern data to detect the respiratory parameters and mask characteristics.

[0036] In one embodiment of the present invention, the said data processing module is adapted to compute the sensed breathing pattern data to measure variation in resistance of the said sensing element with time.

[0037] Accordingly, the said data processing module is then adapted to analyze amplitude of raw signal of the resistance with the time and/or to analyze change in base-line variation of the resistance to detect the mask fit. [0038] In the said embodiment of the present invention, the mask fit is evaluated as:

- a correct fit when the relative humidity (RH) varies within the mask from 80-97% denoting to normalized resistance (AR/R) < 0, where AR/R = (Rf-Ri)/Ri; Ri and Rf denote to ambient resistance and resistance at correct fit, respectively.

[0039] - a loose fit when RH build-up within the mask reduces <80% denoting to normalized resistance (AR/R) > 0, where AR/R = (Rf-Ri)/Ri; Ri and Rf denote to resistance at correct fit and resistance at loose fit, respectively. In another embodiment of the present invention, the data processing module is adapted to analyze the change in amplitude of the raw signal of the resistance to detect the mask fit. The “raw signal” herein refers to the sinusoidal signal.

[0040] The amplitude of the signal reduces drastically by more than 85% when the mask is loosely fit.

[0041] In one embodiment of the present invention, the said data processing module is further adapted to analyze amplitude of raw signal of resistance with time to detect the said mask saturation. The said mask saturation may also be detected by analyzing change in cycle time of the raw signal of the resistance with the time.

[0042] In the embodiment of the present invention, the said mask is evaluated as:

-fully saturated when the response of the resistance signal is in the range of 110- 130 kQ, and/or the cycle time of the resistance signal reduces by 33%.

- half saturated when the response of the resistance signal is in the range of 135- 140 kQ, and/or the cycle time of the resistance signal reduces by 28%.

- quarterly saturated when the response of the resistance signal is in the range of 145-150 kQ, and/or the cycle time of the resistance signal reduces by 25%.

[0043] In one embodiment of the present invention, the said integrated communication module is adapted to provide wired or wireless communication of the said mask with a smart handheld device. [0044] In the embodiment of the present invention, the said smart handheld device is adapted to output the detection information of the said mask fit and the mask saturation to the user, and provide a notification to the user. The said notification being related to the mask fit, mask saturation, breathing characteristics, breathing based diseases, or the like.

[0045] In one embodiment of the present invention, the said mask includes a temperature sensing element having a printed hetero junction configured to the smart mask to detect exhaled breath temperature based on induced thermoelectric response of the hetero junction. [0046] In the said embodiment of the present invention, the said printed hetero junction includes a carbon-based ink of expanded graphite or rGO, and a metal- based ink. The metal-based ink is selected from at least one of silver, copper, gold, nickel, chromium, magnesium, silicon, aluminum, platinum, tin, or rhodium.

[0047] This together with the other aspects of the present invention along with the various features of novelty that characterized the present disclosure is pointed out with particularity in claims annexed hereto and forms a part of the present invention. For a better understanding of the present disclosure, its operating advantages, and the specified objective attained by its uses, reference should be made to the accompanying descriptive matter in which there are illustrated exemplary embodiments of the present invention.

DESCRIPTION OF THE DRAWINGS

[0048] The advantages and features of the present invention will become better understood with reference to the following detailed description taken in conjunction with the accompanying drawings, in which:

[0049] Fig. 1A illustrates a perspective view of a smart respirator _)· mask with a relative humidity sensing element, according to various embodiments of the present invention; [0050] Fig. IB illustrates an exploded view of a detachable sensor device of the smart mask of Fig.1 A, according to various embodiments of the present invention;

[0051] Fig. 1C illustrates a schematic diagram of a communication module attached to the relative humidity sensing element of Fig. 1A, according to various embodiments of the present invention;

[0052] Fig. 2A illustrates an exterior view of the smart respiratory mask of Fig. 1A with the detachable sensor device of Fig. IB, according to various embodiments of the present invention;

[0053] Fig. 2B illustrates an interior view of the smart mask of Fig. 1A with the detachable sensor device of Fig. IB, according to various embodiments of the present invention;

[0054] Fig. 3 illustrates a perspective view of the detachable sensor device of Fig. IB with an inner housing component and an outer housing component, according to various embodiments of the present invention; [0055] Fig. 4 illustrates a graph representing an ohmmeter reading of the mask of

Fig. 1A in different scenarios, according to various embodiments of the present invention;

[0056] Fig. 5A illustrates a graph representing a response of the relative humidity sensing element when the mask is fully saturated, half saturated, and quarterly saturated, according to various embodiments of the present invention;

[0057] Fig. 5B illustrates a graph representing a reduction of cycle time when several layers of oil have been sprayed on the smart respirator}' mask of Fig. 1A, according to various embodiments of the present invention;

[0058] Fig. 6 illustrates a graph representing a breathing pattern of the user wearing the smart respirator}' mask of Fig. 1A, according to various embodiments of the present invention; and [0059] Fig. 7 illustrates a flowchart depicting a method for detecting respiratory parameters and mask characteristics via the smart mask, according to various embodiments of the present invention.

[0060] Like numerals denote like elements throughout the figures.

DESCRIPTION OF THE INVENTION

[0061] The exemplary embodiments described herein detail for illustrative purposes are subjected to many variations. It should be emphasized, however, that the present invention is not limited to as disclosed. [0062] It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but these are intended to cover the application or implementation without departing from the spirit or scope of the present invention.

[0063] Specifically, the following terms have the meanings indicated below. [0064] The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items.

[0065] The terms “having”, “comprising”, “including”, and variations thereof signify the presence of a component.

[0066] The present invention relates to a respiratory face mask. More specifically, the present invention discloses a smart face mask capable of being worn by a user for detection of respiratory parameters and other mask characteristics. The smart face mask can also be called as smart respiratory mask, or the like.

Mode for Invention [0067] The inventive aspects of the invention along with various components and engineering involved will now be explained with reference to Figs. 1A-7 herein. [0068] Referring to Figs. 1A & 2A, the smart respiratory face mask (1000) includes an antimicrobial textile substrate (101) adapted to be wrapped around the user’s respiratory orifices.

[0069] The said textile substrate (101) is adapted to restrict microbes and particulate matter from entering inside the body of the user. Suitable examples of the textile substrate (101) may include but are not limited to polyester, polyester- vinyl composites, vinyl, and even acrylics (refer Figs. 1A & 2A).

[0070] In an embodiment of the present invention, the said smart mask (1000) further includes a sensor device (102) detachably connected to the said substrate (101). The sensor device (102) is main component of the smart mask (1000) (refer

Fig. IB).

[0071] Specifically, the said sensor device (102) includes an inner housing (201) and an outer housing (202) (refer Figs. 2A-3).

[0072] In an embodiment of the present invention, the said inner housing (201) includes a first inner plastic mount (301), and a first outer plastic mount (305) adapted to be aligned with the said first inner plastic mount (301). The said inner housing (201) further may include an inner coupling element (304) (refer Figs. IB & 3). The said inner housing (201) is adapted to be attached to a first side (104) or an interior side of the said textile substrate (101). [0073] In one embodiment of the present invention, the said outer housing (202) includes a second inner plastic mount (306), and a second outer plastic mount (308) adapted to align with the second inner plastic mount (306) (refer Fig. 1A & 3).

[0074] The said outer housing (202) further includes an outer coupling element (307) (refer Figs. 1A & 3). The said outer housing (202) is adapted to be attached to a second side (106) or an exterior side of the said textile substrate (101).

[0075] Referring to Fig. 1A, the said outer coupling element (307) is adapted to detachably coupled with the said inner coupling element (304), thereby enabling the said sensor device (102) to be either attachable or detachable to the said textile substrate (101). [0076] In the said embodiment of the present invention, the said inner coupling element (304) is an inner magnetic element (304), and the said outer coupling element (307) is an outer magnetic element (307) (refer Figs. 1A-1B).

[0077] More specifically, the said inner housing (201) and the said outer housing (202) adhere to the said substrate (101) from first side (104) and the second side (106), respectively, via a magnetic attraction produced between the said inner magnetic element (304) and the outer magnetic element (307) (refer Figs. 1A-1B).

[0078] It should be understood that detachable coupling of the sensor device (102) may alternatively be done by other means as well. For example, in an embodiment of the invention, the sensor device (102) may be attachable or detachable to the said textile substrate (101) by other means, such as a Velcro, a mechanical mount, fastening element, sticking, or the like.

[0079] In one embodiment of the present invention, the said sensor device (102) includes a relative humidity (RH) sensing element (302). The RH sensing element (302) is attached to a communication module (30) which is configured to a printed circuit board substrate (303) (refer Fig. IB).

[0080] In an embodiment, the said communication module (30) consists of memory (32), microprocessor (34), battery (36), power management circuitry (37), communication circuitry (38), and an input/output interface (refer Fig. 1C).

[0081] In an embodiment, the RH sensing element (302) is made by printing a graphene, and more particularly by printing a reduced graphene oxide (rGO) ink on the said substrate (303). The said ink includes a reduced graphene oxide (rGO) amount of 70-99.9 wt% doped with at least one metal oxide loading of 0.1-30 wt%.

[0082] The term “graphene” is an allotrope of carbon consisting of a single layer of atoms arranged in a two-dimensional honeycomb lattice. The graphene is more conductive than copper. With such unique and beneficial physical properties, graphene, and in particular, high quality graphene, is desirable for use in making sensing element. [0083] Further, the “reduce graphene oxide” herein refers to a form of graphene oxide that is processed chemically to reduce the oxygen content, while the “graphene oxide” is a chemically modified graphene prepared by oxidation and exfoliation of graphite , causing extensive oxidative modification of the basal plane.

[0084] In various embodiments, the said metal oxide is selected from at least one of Tin (IV) oxide (SnC ), Zinc oxide (ZnO), Indium tin oxide (ITO), or Tungsten trioxide (W O3) or their combinations. However, it should be noted that such list of metal oxide is exemplary and other metal oxides may be alternatively used.

[0085] In an embodiment of the present invention, the said reduced graphene oxide (rGO) used for making the sensing element (302), is being produced by a reduction method by using graphene oxide (GO) and Stannous chloride dihydrate.

[0086] In the embodiment of the present invention, the graphene oxide (GO) is being synthesized from graphite in a high degree of oxidation and exfoliation.

[0087] In an exemplary embodiment of the present invention, firstly, the graphite is being added with Sulfuric acid (H2SO4) in a vessel. Subsequently, Potassium permanganate (KMnO-i) is added to the obtained mixture, while stirring for several hours, and specifically for more than 8 hours. After that, quenching is required with hydrogen peroxide (H2O2) and/or water (H2O) or ice to obtain supernatant and a graphene oxide slurry.

[0088] Alternatively, the graphene oxide slurry may be exfoliated by adding a portion of the graphene oxide slurry dropwise to an aqueous solution, and then ultra- sonicating the aqueous solution/graphene oxide slurry to obtain monomolecular or substantially monomolecular sheets of the graphene oxide. These sheets may then be reduced to obtain reduced graphene oxide, the graphene form.

[0089] In the said embodiment of the present invention, the said obtained graphite oxide (GO) is then mixed with stannous chloride dihydrate (SnCk.2H20) in a ratio of 1 : 1 to 1 : 10 by weight. Thereafter, the said mixture is sonicated in water for about 3 hours to obtain the aforesaid rGO. [0090] Further, the said resulting mixture is then washed by distilled water and 99% ethanol, respectively to remove impurities, and then dried at 60 °C for about 12 hours.

[0091] As we know Stannous chloride (SnCk) is known as a strong reducing agent in chemical field. In that manner, the stannous chloride being adapted to reduce GO chemically, and contemporarily produce “Tin (IV) oxide" (SnOi) on the basal plane of the reduced graphene oxide (rGO).

[0092] In the embodiment of the present invention, the said reduction method results in chemical, electrical, and morphological variations twisted on rGO. [0093] These variations lead to enhanced moisture absorption and desorption characteristics to the final composite material i.e. reduce graphene oxide ink (rGO).

[0094] In the said embodiment of the present invention, the final composite material, i.e. the reduced graphene oxide (rGO) ink includes chemical elements including carbon (C), tin (Sn), and oxygen(O) in an atomic ratio in a range of 1.0:0.05-0.3:0.1-0.7 respectively.

[0095] Accordingly, the final composite material, i.e. tin (IV) oxide (Sn02)-reduce graphene oxide (rGO) composite exhibits a considerably high sensing performance, with rapid response and reproducibility. Furthermore, the performance is very stable for a long time under normal operating conditions. Moreover, the said high performance could be achieved even at room temperature without providing any external heat. Therefore, it is suggested that the composite material has immense potential in the application as a sensor.

[0096] In addition, the said reduce graphene oxide (rGO) ink is having a Raman Id/Ig ratio in a range of 0.9 to 1.1. The said Raman Id/Ig ratio depicts the defective nature of the said rGO ink. The lateral size of the rGO is less than or equal to 100 micrometer (pm).

[0097] In the said embodiment of the present invention, said rGO ink is being adapted to absorb/adsorb and desorb moisture for sensing breathing pattern of the user based on the said absorption and the desorption of the moisture. The breathing pattern herein refers to the amount of inhalation air and exhalation air, based on the adsorption and desorption of moisture or humidity.

[0098] Specifically, the said sensing element (302) senses the breathing pattern of the user when the air during inhalation and exhalation touches the printed rGO ink of the said sensing element (302). Subsequently, the generated signals will be detected by the said communication module (30).

[0099] Subsequently, the sensed breathing pattern data are transferred to a data processing module (110) via the said generated signals for computation of the said data. The data processing module (110) will be explained later in the invention. [00100] In one embodiment of the invention, the RH sensing element (302) is a resistance-based circuit, thereby the said rGO ink changes resistivity of the said sensing element (302) in a range of 100 ohms to 100 mega ohms within 0.01-3 seconds on exposure to moisture.

[00101] In the above embodiments of the present inventions, the said sensing element (302) is configured at inward side of the print circuit board (PCB) substate (303) in vicinity of nostrils of the user.

[00102] The compatible substrate (303) of the PCB is selected from a group of at least one of thermoplastic or thermosetting polymers, or the like. Other materials which have compatibility to the rGO may equally be used. [00103] In another embodiment ofthe present invention, the sensing element (302) is configured at an exterior of the said smart mask (1000) with the said sensing element (302) is facing towards the ambient environment.

[00104] More specifically, the components (201), (202) are interchangeable, so that the sensing element (302) may be facing towards the ambient environment. [00105] In the said embodiment of the present invention, the said sensing element

(302) is adapted to detect the ambient humidity. The said modification is beneficial to asthma patients who are not supposed to inhale high humid air. [00106] In one embodiment of the present invention, the sensor device ( 102) further includes a display print (309) such as a logo of a manufacturing industry or company.

[00107] In one embodiment of the present invention, the sensor device ( 102) further includes an indicator ring (310) (refer Fig.lA).

[00108] In one embodiment of the present invention, the said indicator ring (310) is configured at the exterior of the said mask (1000) (refer Fig.1A).

[00109] In the embodiment of the present invention, the said indicator ring (310) is an LED array, which lights up when the said mask (1000) is not fit, saturated and carbon di -oxide (CO2) build up is high. In addition, the said indicator ring (310) blinks (as an indicator) when the unit is powered.

[00110] In another embodiment of the present invention, the said indicator ring (310) is configured at an interior of the said mask (1000).

[00111] In one embodiment of the present invention as shown in Fig. IB, the said smart respirator _} mask (1000) may further include the data processing module (110) operatively coupled with the said communication module (30).

[00112] In one embodiment of the present invention, the said data processing module (110) is built-in with said sensor device (102).

[00113] In another embodiment of the present invention, the said data processing module (110) is built-in with a smart handheld device (400). More specifically, the said data processing module (110) is a software application of the said smart handheld device (400).

[00114] The said data processing module (110) is adapted to compute the sensed breathing pattern data to detect the respiratory parameters and mask characteristics.

[00115] In one embodiment of the present invention, the said data processing module (110) is adapted to compute the sensed breathing pattern data by measuring the variation in resistance of the said sensing element (302) with time. [00116] Accordingly, the said data processing module (110) is then adapted to analyze amplitude of the raw signal of the resistance with the time and/or to analyze change in base-line variation of the resistance to detect the mask fit.

[00117] The term “mask fit” refers to snugness of the mask with the face of the user. Specifically, the “mask fit” refers to the correctness of wearing the mask without any gap in between the mask periphery and the face of the user wearing the said mask.

[00118] In the said embodiment of the present invention, the mask fit is evaluated as:

-a correct fit when the relative humidity (RH) varies within the mask (1000) from 80-97% denoting to normalized resistance (AR/R) < 0, where the AR/R = (Rf-Ri)/Ri; Ri and Rf denote to ambient resistance and resistance at correct fit, respectively, and

[00119] -a loose fit when RH build-up within the mask reduces to <80% denoting normalized resistance (AR/R) < 0, where the AR/R = (Rf-Ri)/Ri; Ri and Rf denote to ambient resistance and resistance at correct fit, respectively. In another embodiment of the present invention, the data processing module (110) is adapted to analyze the change in amplitude of the raw signal of the resistance to detect the mask fit.

[00120] The amplitude of the signal reduces drastically by more than 85% when the mask (1000) is loosely fit.

[00121] Similarly, in one embodiment of the present invention, the mask fit being an incorrect fit when the base-line variation in resistance is more than 33%.

[00122] In the exemplary embodiment of the present invention, a methodology of the mask fit will now be explained using a graph shown in Fig. 4. The graph shows the ohmmeter reading of the smart mask (1000).

[00123] In the said embodiment of the present invention, a pen is inserted in the said mask (1000) to create a gap of around 0.5 cm. Accordingly, the said sensing element (302) detects the mask fit as “mask loose” (refer Fig. 4). [00124] Thereafter, the said sensing element (302) detects as “metal plate loose” when a metal plate or strip of the said mask (1000) is loose (refer Fig. 4).

[00125] In one embodiment of the present invention, the metal strip (not shown in figures), also called as nose bridge strip. The said strip allows the said mask (1000) to “be shaped to form against the user's or wearer’s nose to help provide a better fit”. The said strip is made of a material selected from at least one of metal or plastic.

[00126] Again, referring to Fig. 4, the said sensing element (302) detects as “metal plate tightened” when the metal plate being tightened to the specified limit.

[00127] Coming back to the data processing module (110), the said module (110) is further adapted to analyze amplitude of raw signal of resistance with time to detect the said mask saturation.

[00128] The term “mask saturation” used herein refers to the drop in filtration efficacy and breathability of the said mask (1000) due to the blockages of the pores of the filter media due to particulate matter, dust, etc.

[00129] The said mask saturation may also be detected by analyzing change in cycle time of the raw signal of the resistance with the time.

[00130] In one embodiment of the present invention, the mask saturation may also be detected by analyzing change in base line variation in the resistance.

[00131] In the embodiment of the present invention, the said mask (1000) is evaluated as:

- fully saturated when the response of the resistance signal is in a range of 110-130 kiloohm (kQ), and/or the cycle time of the resistance signal reduces to 33% (refer Figs. 5A & 5B).

- half saturated when the response of the resistance signal is in a range of 135-140 kiloohm (kQ), and/or the cycle time of the resistance signal reduces to 28% (refer Fig. 5A & 5B). - quarterly saturated when the response of the resistance signal is in a range of 145- 150 kiloohm (kO). and/or the cycle time of the resistance signal reduces to 25% (refer Fig. 5A & 5B).

[00132] In the exemplary embodiment of the present invention, a methodology of the mask saturation will now be explained using graphs shown in Figs. 5A & 5B.

[00133] In the said embodiment of the present invention, the mask (1000) is saturated using a commercially available sprayable oil can.

[00134] Specifically, several layers of oil have been sprayed on the outer layer from the exterior of the mask (1000). [00135] Accordingly, an oil-coated mask is then connected electrically to an ohmmeter for measuring the resistance while the user is wearing the said mask (1000) (refer Figs. 5A & 5B).

[00136] Referring to Fig. 5B, the resistance of the sensing element (302) reduces as the mask (1000) is gradually saturated using oil spray. More specifically, due to the said saturation, the relative humidity within the mask (1000) increases which results in a reduction of the resistance.

[00137] In the embodiment of the present invention, the exemplary data witch reference to Figs. 5 A & 5B is shown in table- 1 below:

Table- 1 [00138] In one embodiment of the present invention, the said sensing element is self-reviving upon its moisture saturation and autonomy reverts to its base-line resistance. [00139] In one embodiment of the present invention, the data processing module ( 110) is further adapted to calculate the respiratory rate or breathing rate of the user wearing the said mask (1000).

[00140] The term “respiratory rate” as used herein refers to the number of breaths per minute of the user while wearing the mask (1000).

[00141] More specifically, the said calculation of the respiratory rate also termed as breathing rate is based on ‘resistance vs time’ sinusoidal signal (during inhale and exhale). In the sinusoidal signal, the peak resistance value and minimum resistance value denote to inhale and exhale, respectively (refer Fig. 6). [00142] In the embodiment of the present invention, the calculated respiratory rate of an adult deem to be 12-20 per min, 20-30 per min and 30-45 per min under, at- rest/slow walking (normal or long breath), jogging (normal or short breath), and running (short breath) conditions, respectively for an adult user wearing the mask (1000). [00143] In the exemplary embodiment of the present invention, the respiratory rate is calculated when the sensing element (302) is placed at an interior of the textile substrate (101), and specifically, within 2 cm under nostrils.

[00144] The exemplary data with reference to the said experimentation is shown in table-2 below: able-2

[00145] Accordingly, this may allow the user to detect unusual breathing patterns related to contagious or chronic respiratory issues.

[00146] In one embodiment of the present invention, the said integrated communication module is adapted to provide wired or wireless communication of the said mask (1000) with the smart handheld device (400) (refer Figs. IB & 1C). [00147] In the embodiment of the present invention, wireless communication is selected from Bluetooth communication, NFC communication, infrared communication, internet connection, or the like.

[00148] In the exemplary embodiment of the present invention, the said integrated communication module is adapted to start a Bluetooth function to establish a connection with a terminal of the said smart handheld device (400) via a Bluetooth signal.

[00149] Accordingly, the detection information related to the respiratory parameters and the mask characteristics is then transferred to the said smart handheld device (400).

[00150] In the embodiment of the present invention, the said smart handheld device (400) is adapted to output the detection information of the respiratory parameters and the mask characteristics to the user. The detection information may be outputted on a display of the said device (400) via the app of the smart handheld device (400).

[00151] Further, the said smart handheld device (400) provides a notification/alarm to the user via a text message, video message, or audio message, or the like. The said notification being related to the mask fit, mask saturation, breathing based diseases, or the like.

[00152] In one embodiment of the present invention, the handheld device (400) is a smart phone. Other suitable examples of the smart handheld device (400) may include but are not limited to tablets, laptop, and MacBook.

[00153] In an embodiment of the present invention, the said smart mask (1000) further includes a temperature sensing element having a printed hetero junction configured at the interior of the smart mask (1000) for detecting exhaled breath temperature based on induced thermoelectric response of the hetero junction.

[00154] The printed hetero junction is made of at least one of carbon-based ink of expanded graphite or rGO, and/or a metal-based ink.

[00155] The said metal-based ink is selected from at least one of silver, copper, gold, nickel, chromium, magnesium, silicon, aluminum, platinum, tin or rhodium. [00156] In another embodiment of the present invention, the said temperature sensing element is configured at the exterior of the said mask (1000) for detecting ambient temperature.

[00157] In the various embodiments of the present invention, the components of the said mask (1000) be attached at any location of the face mask in order to detect the respiratory characteristics.

[00158] The underlying method (50) for detecting respiratory parameters and other mask characteristics, such as respiratory rate, mask fit, and mask saturation by the said smart face mask (1000) will now be explained with reference to a flow chart (refer Fig. 7).

[00159] At step (10), the method (50) involves sensing breathing pattern via a relative humidity sensing element (302). The sensing of the breathing pattern is based on absorption and desorption of moisture by the said sensing element (302).

[00160] Further, at step (12), the method (50) involves transferring the breathing pattern data to a data processing module (110). The said data processing module (110) being operatively coupled with a communication module (30).

[00161] The method (50) is followed by computing the breathing pattern data for detecting the respiratory rate, the mask fit and the mask saturation via the said data processing module (110) at step (14) (refer Fig. 7).

[00162] In the embodiment of the present invention, the computing of the breathing pattern data for detecting the mask fit includes measuring variation in resistance of the said printed sensing element (302) with time. Accordingly, analyzing amplitude of raw signal of the resistance with the time, and/or change in base-line variation in resistance.

[00163] In one embodiment of the present invention, the computing of the breathing pattern data for detecting the mask saturation comprises measuring variation in resistance of the said sensing element (302) with time. Accordingly, analyzing the change in amplitude of raw signal of the resistance with the time, and/or analyzing change in cycle time of raw signal of the resistance with the time. [00164] The method (50) at last involves step (16), the step (16) includes outputting the said detected information of the respiratory rate, mask fit and the mask saturation on a smart handheld device (400).

[00165] In one embodiment of the present invention, the detected information related to the respiratory parameters and the mask characteristics may also be transferred to a cloud storage for Internet of Things (IoT). In this hyperconnected world, digital systems can record, monitor, and adjust each interaction between connected things.

Advantages of the Invention

[00166] In the various embodiments of the present invention, the smart mask detects various respiratory parameters and mask characteristics by using only single sensing element.

[00167] Further, the sensing element (302) of the present invention is extremely sensitive to moisture adsorption and desorption characteristics. Also, the said sensing element reduces the response time for detecting breathing patterns. The said sensing element may be configured at anywhere in the mask, and get the same data related to the respiratory parameters and the other mask characteristics.

[00168] Furthermore, the said smart mask of the present invention may provide the ulterior protection to the user wearing the said mask.

[00169] In addition, the said sensing element also detects the usability of certain reusable masks and notify the user via the smart held device.

[00170] In nutshell, the smart mask of the present invention may overcome the above-discussed drawbacks and provide easy to operate and cost-effective mask.

Industrial Applicability

[00171] The smart mask as disclosed in the present invention, is useful in detection of respiratory parameters and other mask characteristics such as respiratory rate, mask fit and mask saturation by configuring to the various respiratory masks available in the market.

[00172] The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching.

[00173] Further, the embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, and thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated.

[00174] It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but such omissions and substitutions are intended to cover the application or implementation without departing from the spirit or scope of the present invention.