EP4213667A1

EP4213667A1 - Aerosol generation device comprising a measurement circuitry and associated operation method

Info

Publication number: EP4213667A1
Application number: EP21773821.0A
Authority: EP
Inventors: Jian Cheng LUO; Marina DUFOUR; Olaf JANSON; Robert ALIZON; Theo Verlaan
Original assignee: JT International SA
Current assignee: JT International SA
Priority date: 2020-09-15
Filing date: 2021-09-14
Publication date: 2023-07-26
Also published as: WO2022058320A1; JP2023539988A

Abstract

The present invention concerns an aerosol generation device (10) designed to operate according to several operation modes and comprising: - a housing (12) extending along a device axis (X); - a measurement circuitry (28) configured to generate, while the device (10) is handheld by a user, bioimpedance measurements relative to the user's body bioimpedance; - a control circuitry (30) comprises a control module (43) configured to extract control features from the bioimpedance measurements, compare the control features with reference features and basing on this comparison, authenticate the user.

Description

Aerosol generation device comprising a measurement circuitry and associated operation method

FIELD OF THE INVENTION

The present invention concerns an aerosol generation device comprising a measurement circuitry configured to generate, while the device is handheld by a user, measurements making it possible to authenticate the user.

The present invention concerns also an associated operation method of an aerosol generation device.

BACKGROUND OF THE INVENTION

Different types of aerosol generation devices are already known in the art. In general, such aerosol generation devices are configured to distribute aerosol to a user.

It is desirable to avoid unauthorized use of these aerosol generation devices. Such unauthorized users are for example minors or other individuals that should not use a specific aerosol generation device. Therefore, in general, the devices are stored in places that cannot be reached by unauthorized users. In other cases, the user has to look after the device in order to avoid its unauthorized use. In some other cases, the devices are provided with electronic locking means requiring inputting manually identification or/and controlled by a smartphone associated to the aerosol generation device.

However, a surveillance of the device requires an additional effort from the authorized user, and can thus be inconvenient. Using of electronic locking means may be too restrictive and may require from certain users an additional effort.

SUMMARY OF THE INVENTION

One of the aims of the invention is to provide an aerosol generation device that allows preventing unauthorized use without requiring an additional effort from the user.

For this purpose, the invention relates to an aerosol generation device designed to operate according to several operation modes and comprising: - a housing extending along a device axis;

- a measurement circuitry configured to generate, while the device is handheld by a user, bioimpedance measurements relative to the user’s body bioimpedance;

- a control circuitry comprises a control module configured to extract control features from the bioimpedance measurements, compare the control features with reference features and basing on this comparison, authenticate the user.

Indeed, the device can only be used by the authorized user(s), and prevents unauthorized use thanks to the authentication of the user. The device is very convenient to use, because the device is able to measure the user’s body bioimpedance when the device is handheld by the user. The device is thus able to authenticate the user without requesting the user for example to input manually an identification information and/or to pair it to a smartphone.

According to some embodiments, the measurement circuitry comprises a pair of measurement sensors designed to be in contact with the user’s skin while the device is handheld by the user and a processing module configured to generate a measurement signal on one of the measurement sensors acquire a response signal from the other measurement sensor and generate the bioimpedance measurements by analyzing the measurement signal and the response signal..

According to some embodiments, the measurement circuitry further comprises a reference sensor designed to be in contact with the user’s skin at least temporary while the device is handheld by the user, the processing module being further configured to use the reference sensor as a measurement reference.

Thanks to these features, the bioimpedance measurements are improved. Indeed, for example, different measurements can be normalized by using the measurement reference.

According to some embodiments, each sensor protrudes from an external surface of the housing or forms a part of this external surface, and is electrically isolated from the housing.

Thanks to these features, any possible interferences in the bioimpedance measurements, for example induced by conduction of the measurement signal via the housing, are at least reduced or eliminated. Additionally, thanks to these features, the bioimpedance measurements can be done with a single handheld device, i.e. without additional devices and/or sensors on different parts of the body of the user.

According to some embodiments, the reference sensor is arranged between the measurement sensors.

Thanks to these features, the measurement reference takes into account measurement conditions of both sensors of the pair of measurement sensors, and provides thus a reliable reference.

According to some embodiments the housing extends along the device axis between a mouthpiece end and a battery end; one of the measurement sensors is arranged at the mouthpiece end of the housing and the other measurement sensor is arranged at the battery end of the housing.

Thanks to these features, the acquired response signal from the other measurement sensor of the pair of measurement sensors is a function of the user’s body bioimpedance measured over the distance between the mouthpiece end of the housing and the battery end of the housing. In particular, taking into account this long distance, the measurement is more reliable.

According to some embodiments, the control circuitry comprises an automatic activation element configured to activate automatically at least one operation mode of the device; at least one of the sensors presents at least partially circumferential shape extending around the device axis.

Thanks to these features, the aerosol generation device can be activated while it is handheld by the user independently of its orientation in the user’s hand.

According to some embodiments, the control circuitry comprises a manual activation element arranged on an external surface of the housing and configured to activate at least one operation mode of the device further to a user interaction with the element; at least one of the sensors being arranged on the external surface of the housing on the opposite side of the manual activation element or is integrated into the activation element. Thanks to these features, a contact of the at least one sensor with the user’s hand is ensured, as a handheld position of the user is predefined by the manual activation element. Additionally, at least one sensor is arranged so as to be in contact with the user’s hand. Furthermore, the user can be authenticated simultaneously with the manual activation of the device. Finally, in the case when the sensor is integrated into the activation element, the user experience is further augmented, as the device presents a design which is particularly sober.

According to some embodiments, at least one of the sensors extends over at least one edge formed by the housing.

Thanks to these features, the user contacts the sensor for example with the base of the thumb when the device is handheld.

According to some embodiments, the measurement signal is a pulse voltage signal, preferably of a block wave shape.

Thanks to these features the measurement can be very short, and still provide enough information to distinguish an authorized user.

According to some embodiments, the processing module is configured to generate the bioimpedance measurements by performing several measurement cycles, the generated bioimpedance measurements presenting averaged measurements over the measurement cycles.

Thanks to these features, the reliability of the bioimpedance measurements is improved.

According to some embodiments, the control module is configured to extract the control features from the bioimpedance measurements using Fast Fourier Transforms.

Thanks to these features, for example non-characteristic data and noise can be eliminated. Also, thanks to these features, the remaining data is reduced, and the data is thus easier to process. According to some embodiments, in a calibration operation mode, the control module is configured to extract control features from the bioimpedance measurements and store these features as reference features.

Thanks to these features, the control features extracted in the calibration mode are memorized in a safe manner inside the aerosol generation device.

According to some embodiments, if the user is authenticated, the control module is configured to trigger a normal operation mode of the device, otherwise, the control module is configured to trigger a degraded operation mode of the device or deactivate the device.

The invention also relates to an operation method of an aerosol generation device designed to operate according to several operation modes, the operation method comprising:

- generate, while the device is handheld by a user, bioimpedance measurements relative to the user’s body bioimpedance;

- extract control features from the bioimpedance measurements;

- compare the control features with reference features and basing on this comparison, authenticate the user.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention and its advantages will be better understood upon reading the following description, which is given solely by way of non-limiting example and which is made with reference to the appended drawings, in which:

- Figure 1 is a schematic diagram of an aerosol generation device according to the invention in a first embodiment of the invention;

- Figure 2 is a schematic view in perspective of the aerosol generation device of Figure 1 ;

- Figure 3 is a flowchart of an operation method according to the first embodiment of the invention, the operation method being carried out by the aerosol generation device of Figure 1 ; - Figure 4 is a schematic view in perspective of an aerosol generation device according to a second embodiment of the invention; and

- Figure 5 is a schematic view in perspective of an aerosol generation device according to a third embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Before describing the invention, it is to be understood that it is not limited to the details of construction set forth in the following description. It will be apparent to those skilled in the art having the benefit of the present disclosure that the invention is capable of other embodiments and of being practiced or being carried out in various ways.

As used herein, the term “aerosol generation device” or “device” may include a vaping device to deliver an aerosol to a user, including an aerosol for vaping, by means of aerosol generating unit (e.g. an aerosol generating element which generates vapor which condenses into an aerosol before delivery to an outlet of the device at, for example, a mouthpiece, for inhalation by a user). The device may be portable. “Portable” may refer to the device being for use when held by a user. In particular, the device is configured for being handheld by a user, i.e. for being in contact with the skin of a hand of the user. The device may be adapted to generate a variable amount of aerosol, e.g. by activating a heater system for a variable amount of time (as opposed to a metered dose of aerosol), which can be controlled by a trigger. The trigger may be user activated, such as a vaping button and/or inhalation sensor. The inhalation sensor may be sensitive to the strength of inhalation as well as the duration of inhalation to enable a variable amount of vapor to be provided (so as to mimic the effect of smoking a conventional combustible smoking article such as a cigarette, cigar or pipe, etc.). The device may include a temperature regulation control to drive the temperature of the heater and/or the heated aerosol generating substance (aerosol pre-cursor) to a specified target temperature and thereafter to maintain the temperature at the target temperature that enables efficient generation of aerosol.

As used herein, the term “aerosol” may include a suspension of precursor as one or more of: solid particles; liquid droplets; gas. Said suspension may be in a gas including air. Aerosol herein may generally refer to/include a vapor. Aerosol may include one or more components of the precursor. As used herein, the term “aerosol-forming precursor” or “precursor” or “aerosolforming substance” or “substance” may refer to one or more of a: liquid; solid; gel; mousse; foam or other substances. The precursor may be processable by the heating system of the device to form an aerosol as defined herein. The precursor may comprise one or more of: nicotine; caffeine or other active components. The active component may be carried with a carrier, which may be a liquid. The carrier may include propylene glycol or glycerin. A flavoring may also be present. The flavoring may include Ethylvanillin (vanilla), menthol, Isoamyl acetate (banana oil) or similar. A solid aerosol forming substance may be in the form of a rod, which contains processed tobacco material, a crimped sheet or oriented strips of reconstituted tobacco (RTB).

As used herein, the term “bioimpedance measurement” refers to the measure of the impedance, or resistance, of the body of a user in response to a weak electric current flowing through the body. Impedance refers to the opposition that a circuit presents to the passage of a current and in particular bioimpedance represents the resistance offered by a biological medium to the flow of alternating current.

A bioimpedance measure is different from a biometric measure, which refers to a more global measure of a human characteristic such as a fingerprint or DNA.

A bioimpedance measure is also different from a biopotential measure which refers to the measurement of the electrical activity associated with the functioning of an organ, be it the heart (ECG) or the brain (EEG) for example.”

FIRST EMBODIMENT OF THE INVENTION

With reference to Figures 1 and 2, an aerosol generation device 10 according to a first embodiment of the invention comprises a housing 12 extending along a device axis X between a mouthpiece end 16 and a battery end 18. The housing 12 comprises at the mouthpiece end 16 a mouthpiece 20 intended to be positioned at the mouth of the user. The housing 12 is for example at least partially made out of a metal or a polymer. As it is visible in particular on Figure 2, the housing 12 forms generally a circular cross-section in a plane perpendicular to the device axis X. Additionally, the housing 12 defines an external surface 19 and delimits an interior part 22 of the aerosol generation device 10. The interior part 22 of the device 10 comprises notably vaping equipment 24 designed to generate aerosol from a precursor and a power block 26 designed to power the device 10. The interior part 22 of the device 10 may comprise other internal components performing different functionalities of the device 10 known in the art.

It should be noted that Figure 1 presents only a schematic diagram of different components of the aerosol generation device 10 and does not necessarily show the real physical arrangement and dimensions of these components. In particular, such an arrangement can be chosen according to the design of the aerosol generation device 10 and technical features of its components.

With reference to Figure 1 , the aerosol generation device 10 further comprises a measurement circuitry 28 configured to generate, while the device 10 is handheld by the user, bioimpedance measurements relative to the user’s body bioimpedance, and a control circuitry 30 configured to extract control features from the bioimpedance measurements, compare the control features with reference features and basing on this comparison, authenticate the user.

The bioimpedance measurements present in particular a voltage over time signal, i.e. in particular a signal in the time domain. Each control feature presents in particular a spectral density of a respective frequency band from a plurality of frequency bands of the bioimpedance measurements, such as between 20 and 100 frequency bands, in the frequency domain. Each control feature is specific to each user. The control feature may in particular allow an authentication of the user. Each reference feature presents a reference spectral density, for example measured as a reference or being predefined, of a frequency band corresponding to a frequency band of a respective control feature. Each reference feature is used to verify the authenticity of the corresponding control feature, as it will be explained below.

In the examples of Figures 1 and 2, the measurement circuitry 28 comprises a pair of measurement sensors 32, 34 designed to be in contact with the user’s skin while the device 10 is handheld by the user, in particular with the user’s hand skin. The measurement circuitry 28 may further comprise a reference sensor 36 designed to be in contact with the user’s skin at least temporary while the device 10 is handheld by the user.

Each sensor 32, 34, 36, such as the measurement sensors 32, 34 and/or the reference sensor 36, may protrude from the external surface 19 of the housing 12. According to another example, each sensor 32, 34, 36 may form a part of the external surface 19. In both cases, each sensor 32, 34, 36 is electrically isolated from the housing 12. Moreover, each sensor 32, 34, 36 comprises an electrically conductive material.

As visible in particular on Figure 2, each sensor 32, 34, 36 has for example a single contact surface 40. According to a variant, not shown, at least one of the sensors 32, 34, 36 may have several contact surfaces. In this case, the contact surfaces are in particular internally electrically connected.

At least one of the sensors 32, 34, 36 presents at least partially a circumferential shape extending around the device axis X. For example, as visible in particular on Figure 2, each sensor 32, 34, 36 presents a circumferential shape extending totally around the device axis X. With reference to Figure 2, one of the measurement sensors 32 is arranged at the mouthpiece end 16 of the housing 12 and the other measurement sensor 34 is arranged at the battery end 18 of the housing 12.

The sensors 32, 34, 36 present in particular dry contacts. By “dry contacts”, it is understood that no potential difference is present between the respective sensors 32, 34, 36, for example between the two measurement sensors 32, 34. Thanks to the sensors 32, 34, 36 presenting dry contacts, the measurement is in particular possible without any additional device other than the aerosol generation device 10. In particular, the dry contacts allow easy bioimpedance measurements while singlehandedly holding the device 10. Additionally, the measurement quality of the bioimpedance measurements is further improved.

The measurement circuitry 28 may further comprise a processing module 42 configured to generate bioimpedance measurements by analyzing a measurement signal issued from one of the measurements sensors 32, 34 and a response signal received by the other measurement sensor 32, 34. For example, the bioimpedance measurement may be determined by analyzing a difference between characteristics relative to the measurement signal and the response signal. These characteristics can correspond to an amplitude of the corresponding signals or to their voltage. According to a particular example, the processing module 42 is configured to generate the bioimpedance measurements by performing one or several measurement cycles, the number of cycles is for example comprised between 5 and 10. In this case, the generated bioimpedance measurements present for example averaged measurements over the measurement cycles. According to another example, the processing module 42 is configured to analyze each measurement cycle separately.

The processing module 42 may be also configured to generate the measurement signal on one of the measurement sensors 32, 34, preferably on the measurement sensor 32 at the mouthpiece end 16. According to an alternative, the processing module 42 is configured to generate the measurement signal on the measurement sensor 34 at the battery end 18. The measurement signal may be a pulse voltage signal. For example, the measurement signal may be a signal of a block wave shape. According to an example, the measurement signal is a signal changing its amplitude continuously. According to another example, the measurement signal may have a square wave shape. The measurement signal may have voltages up to 10 V, for example a voltage substantially equal to 1 V. The current of the measurement signal is for example function of the voltage. The current of the measurement signal may be at maximum equal to 1 mA. For example, for a voltage comprised between 1 to 3 V, the current may be substantially equal to 0,1 mA.

The processing module 42 is further configured to acquire the response signal from one of the measurement sensors 32, 34, in particular from the measurement sensor 32, 34 different from the sensor used to emit the measurement signal. For example, the processing module 42 is configured to acquire the response signal from the measurement sensor 34 at the battery end 18, in case when the measurement signal is emitted by the measurement sensor 32 at the mouthpiece end 16, or inversely.

According to the examples where the measurement circuitry 28 comprises the reference sensor 36, the processing module 42 may be further configured to use the reference sensor 36 as a measurement reference. For example, the processing module 42 can be configured to generate a reference signal on the reference sensor 36 and to acquire a response to this reference signal, using for example one of the measurement sensors 32, 34. In this case, the processing module 42 is further configured to analyze the response signal to the measurement signal in function of the response signal to the reference signal. For example, the processing module 42 may be configured to normalize the response to the measurement signal by using the measurement reference. The processing module 42 may be further configured to attenuate at least partially or eliminate noise present in the response signal by using the measurement reference. The control circuitry 30 comprises a control module 43 configured to control the operation of the aerosol generation device 10 and an activation element 44 configured to activate the operation of the device 10 by activating the operation of the control module 43. Particularly, the control module 43 presenting for example a microcontroller is configured to control the operation of the aerosol generation device 10 according to an operation mode chosen among a calibration mode, an authentication mode, a normal operation mode and a degraded operation mode.

In the calibration mode, the control module 43 is configured to extract control features from the bioimpedance measurements generated by the processing module 42 and store these features as the reference features. For this purpose, the control module 43 may comprise a database 46 or any other type of memory using to store the reference features. In the authentication mode, the control module 43 is configured to authenticate the user by extracting the control features from the bioimpedance measurements generated by the processing module 42 and by comparing these control features with reference features stored in the database 46. In both calibration and authentication modes, the control module 43 may be configured to extract the control features from the bioimpedance measurements by transforming the bioimpedance measurements into the frequency domain using for example Fast Fourier Transforms. The comparing the control features with the reference features may be performed by comparing the features of the same frequency bands. The control module 43 may be also configured to compare the control features and reference features of a spectrum lower than a predefined threshold only, such as a spectrum lower than 100 Hz, preferably lower than 50 Hz. The control module 43 may be in particular configured to ignore control features of a frequency spectrum equal or higher than the predefined threshold. Indeed, these control features may be prone to reflect noise.

In the normal operation mode, the control module 43 is configured to control the vaping equipment 24 to generate normally the aerosol. In the degraded operation mode, the control module 43 is configured to control the vaping equipment 24 according to degraded characteristics, using for example a low heating temperature and/or aerosol generate rate.

The activation element 44 is for example an automatic activation element configured to generate a signal to the control module 43 to activate automatically at least one operation mode of the device 10, for example the normal operation mode or the degraded operation mode. In particular, the automatic activation element may be formed by a pressure sensor able to detect an airflow in the vaping equipment 24. According to another embodiment, the automatic activation element is formed by the measurement sensors 32, 34. In this case, for example the processing module 42 is configured to detect, via the measurement sensors 32, 34, if the device 10 is handheld by the user, and active the control module 43.

In the case where the activation element 44 is an automatic activation element, as it is visible on Figure 2, at least one of the sensors 32, 34 presents preferably at least partial circumferential shape extending around the device axis X, preferably extending totally around the device axis X. This allows to activate the device 10 independently from the orientation under which the user handhelds the device 10.

An operation method 100 performed by the aerosol generation device 10 according to the first embodiment of the invention will now be explained in reference to Figure 3 presenting a flowchart of its phases and its steps.

During a calibration phase 110, the control module 43 switches the device 10 in the calibration mode. The calibration mode is for example activated by the user while a first using of the device and/or upon introducing a secured command, for example a secured code. During the calibration phase 110, the control module 43 acquires reference features, in particular in the same manner as the control features. For example, the measurement circuitry 28 generates, while the device 10 is handheld by the user, bioimpedance measurements relative to the user’s body bioimpedance as a reference for this user. Then, the control module 43 extracts the reference features from the bioimpedance measurements of the user, and stores these features in the database 46, in particular by transforming the bioimpedance measurements into the frequency domain. For example, the control module 43 may extract the reference features by using Fast Fourier Transforms.

The next phase, called authentication phase 120, is activated by the control module 43, for example at each activation of the control module 43 by the activation element 44, following the calibration phase 110. Particularly, during this phase 120, the control module triggers the authentication mode of the device 10. The authentication phase 120 comprises a generation step 130, an extraction step 132, a comparison step 134 and an authentication step 136. During the generation step 130, the measurement circuitry 28 generates, while the device 10 is handheld by the user, the bioimpedance measurements relative to the user’s body bioimpedance. In particular, the processing module 42 generates the measurement signal on one of the measurement sensors 32, acquires a response signal from the other measurement sensor 34 and generates the bioimpedance measurements by analyzing the measurement signal and the response signal. According to embodiments in which the measurement circuitry 28 comprises the reference sensor 36, the processing module 42 may use the reference sensor 36 as a measurement reference. For example, the processing module 42 may generates a reference signal on the reference sensor 36 and acquires a response to the reference signal. In this case, the processing module 42 may analyze the response signal to the measurement signal in function of a response measured to the reference signal. For example, the processing module 42 may normalize the response signal to the measurement signal by using the measurement reference.

During the extraction step 132, the control module 43 extracts the control features from the bioimpedance measurements, for example by transforming the bioimpedance measurements into the frequency domain, in particular by using Fast Fourier Transforms.

During the comparison step 134, the control module 43 compares the control features with reference features, for example by implementing a suitable comparing logic.

During the authentication step 136, the control module 43 authenticates the user basing on the comparison of the control features with reference features. In particular, the control module 43 compares the control features with the corresponding reference features of a spectrum lower than a predefined threshold only such as lower than 100 Hz, preferably lower than 50 Hz.

The next phase, called operation phase 140, is activated by the control module 43 after the authentication phase 120. In particular, during this operation phase 140, the control module 43 triggers the normal operation mode of the device 10 if the user authentication during the authentication phase 130 is successful. Otherwise, the control module 43 triggers the degraded operation mode of the device or deactivates the device.

SECOND EMBODIMENT OF THE INVENTION With reference to Figure 4, an aerosol generation device 210 according to the second embodiment of the invention is described in the following. The aerosol generation device 210 according to the second embodiment is similar to the aerosol generation device 10 according to the first embodiment, except the differences explained below.

According to the second embodiment of the invention, the aerosol generation device 210 comprises a housing 212 forming generally a circular cross-section in a plane perpendicular to the device axis X like in the previous case, and a control circuitry similar to the control circuitry explained above. This control circuitry comprises notably a control module and an activation element 244. Like in the previous case, the activation element 244 is able to activate the operation of the control module. However, according to the second embodiment, the activation element 244 is a manual activation element arranged on the external surface of the housing 212, as it is visible on Figure 4. The manual activation element 244 presents for example an ON/OFF button and is configured to activate the operation of the control module further to a user interaction with this element. By its function, the manual activation element 244 defines a predetermined orientation of the device 210 in the user’s hand.

According to the second embodiment of the invention, the aerosol generation device 210 further comprises sensors 232, 234, 236 similar to the sensors 32, 34, 36 explained above. However, according to the second embodiment, at least one of the sensors 232, 234, 236, such as the measurement sensor 232 at the mouthpiece end 216, is integrated at least partially into the manual activation element 244. In variant, the measurement sensor 232 may have at least partially a circumferential shape extending through the manual activation element 244 or in the proximity of this element 244. Additionally, at least one of the sensors 232, 234, 236, such as the measurement sensor 234 at the battery end 218 may extend only partially around the device axis X. Particularly, as it is showed on Figure 4, the sensor 234 may present a circumferential shape extending only partially around the device axis X and the sensor 236 may present a circumferential shape extending totally around the device axis X. In this case, the sensor 234 may extend on a side of the housing 212 opposite to the side of the housing receiving the activation element 244. In other words, the arrangement of the sensor 234 is defined in respect with the predetermined orientation of the device 210 in the user’s hand defined by the manual activation element 244. Such an arrangement is particularly advantageous when the user interacts with the activation element 244 while handholding the device 10. For example, the user can interact with the activation element 244 with a finger while keeping contact with all of the three sensors 232, 234, 236.

The operation method performed by the aerosol generation device 210 according to the second embodiment corresponds to the operation method 100 performed by the aerosol generation device 10 according to the first embodiment, taking into account the structural differences of the devices 10, 210.

THIRD EMBODIMENT OF THE INVENTION

With reference to Figure 5, an aerosol generation device 310 according to the third embodiment of the invention is described in the following. The aerosol generation device 310 according to the third embodiment of the invention is similar to the aerosol generation device 10 according to the first embodiment except the differences explained below.

Particularly, the aerosol generation device 310 according to the third embodiment of the invention comprises a housing 312 forming for example a generally rectangular crosssection in a plane perpendicular to the device axis X, as it is visible on Figure 5. For example, the housing 312 has a box shape having a front side 348, a back side 350 parallel to the front side 348 and two lateral parallel sides extending between the back side 350 and the front side 348. The housing 312 is in particular adapted to be handheld by the user in one of two predefined positions, in particular in a position in which the front side 348 faces the user’s palm and position in which the back side 350 faces the user’s palm.

The aerosol generation device 310 according to the third embodiment of the invention also comprises sensors 332, 334, 336 similar to the sensors 32, 34, 36. However, in this case, these sensors 332, 334, 336 are non-circumferential. For example, the measurement sensor 332 may be arranged on the front side 348 of the housing 312 and the other measurement sensor 334 may be positioned on the back side 350 of the housing 312. This is for example illustrated on Figure 5 showing the other measurement sensor 334 with dotted lines. The optional reference sensor 336 may be also positioned on the back side 350. According to an example, the measurement sensors 332, 334, and eventually the reference sensor 336, may comprise each a plurality of contact faces, so as to form symmetrical contact surfaces on both the front side 348 and the back side 350. This allows for example to obtain a compatibility of the device 310 for left and right- handed use.

The aerosol generation device 310 according to the third embodiment may also comprise a manual activation element 344 similar to the manual activation element 244 explained above. As it is visible in the example of Figure 5, the activation element 344 is for example arranged on the front side 348, i.e. on the opposite side of the measurement sensor 334.

According to a variant of the third embodiment, one of the measurement sensors 332, 334 may extend over at least one edge 352 formed by the housing 312 between the front side 348 and one of the lateral sides. This is in particular visible on Figure 5, showing one of the measurement sensors with the reference sign 332’.

The operation method performed by the aerosol generation device 310 according to the third embodiment corresponds to the operation method 100 performed by the aerosol generation device 10 according to the first embodiment, taking into account the structural differences of the device 310 according to the third embodiment described above.

OTHER EMBODIMENTS OF THE INVENTION

One can conceive that other embodiments of the invention are still possible. Particularly, these embodiments may be relative to different shapes of the housing of the aerosol generation device according to the invention, as well as to different shapes/arrangements of the sensors. For example, it is possible to conceive an aerosol generation device having a circular cross-section where the sensors are arranged as explained in reference with the third embodiment of the invention. The manual activation element may be also replaced by an automatic activation element as explained in reference with the first embodiment of the invention.

Claims

1. An aerosol generation device (10; 210; 310) designed to operate according to several operation modes and comprising:

- a housing (12; 212; 312) extending along a device axis (X);

- a measurement circuitry (28) configured to generate, while the device (10; 210; 310) is handheld by a user, bioimpedance measurements relative to the user’s body bioimpedance;

- a control circuitry (30) comprises a control module (43) configured to extract control features from the bioimpedance measurements, compare the control features with reference features and basing on this comparison, authenticate the user.

2. The aerosol generation device (10; 210; 310) according to claim 1 , wherein the measurement circuitry (28) comprises a pair of measurement sensors (32, 34; 232, 234; 332, 334) designed to be in contact with the user’s skin while the device (10; 210; 310) is handheld by the user and a processing module (42) configured to generate a measurement signal on one of the measurement sensors (32, 34; 232, 234; 332, 334), acquire a response signal from the other measurement sensor (32, 34; 232, 234; 332, 334) and generate the bioimpedance measurements by analyzing the measurement signal and the response signal.

3. The aerosol generation device (10; 210; 310) according to claim 2, wherein the measurement circuitry (28) further comprises a reference sensor (36; 236; 336) designed to be in contact with the user’s skin at least temporary while the device (10; 210; 310) is handheld by the user, the processing module (42) being further configured to use the reference sensor (36; 236; 336) as a measurement reference.

4. The aerosol generation device (10; 210; 310) according to claim 2 or 3, wherein each sensor (32, 34; 232, 234; 332, 334) protrudes from an external surface (19) of the housing (12; 212; 312) or forms a part of this external surface (19), and is electrically isolated from the housing (12; 212; 312).

5. The aerosol generation device (10; 210; 310) according to claims 3 and 4, wherein the reference sensor (36; 236; 336) is arranged between the measurement sensors (32, 34; 232, 234; 332, 334).

6. The aerosol generation device (10; 210; 310) according to any one of claims 2 to 5, wherein:

- the housing (12; 212; 312) extends along the device axis (X) between a mouthpiece end (16; 216) and a battery end (18; 218);

- one of the measurement sensors (32, 34; 232, 234; 332, 334) is arranged at the mouthpiece end (16; 216) of the housing (12) and the other measurement sensor (32, 34; 232, 234; 332, 334) is arranged at the battery end (18; 218) of the housing (12).

7. The aerosol generation device (10) according to any one of claims 2 to 6, wherein the control circuitry (30) comprises an automatic activation element (44) configured to activate automatically at least one operation mode of the device (10); at least one of the sensors (32, 34, 36) presents at least partially circumferential shape extending around the device axis (X).

8. The aerosol generation device (210; 310) according to any one of claims 2 to 6, wherein the control circuitry (30) comprises a manual activation element (244; 344) arranged on an external surface of the housing and configured to activate at least one operation mode of the device (210; 310) further to a user interaction with the element; at least one of the sensors (232, 234; 332, 334) being arranged on the external surface of the housing on the opposite side of the manual activation element (244; 344) or is integrated into the activation element (244; 344).

9. The aerosol generation device (310) according to any one of claims 2 to 8, wherein at least one of the sensors (332’) extends over at least one edge (352) formed by the housing (312).

10. The aerosol generation device (10; 210; 310) according to any one of claims 2 to

9, wherein the measurement signal is a pulse voltage signal, preferably of a block wave shape.

11. The aerosol generation device (10; 210; 310) according to any one of claims 2 to

10, wherein the processing module (42) is configured to generate the bioimpedance measurements by performing several measurement cycles, the generated bioimpedance measurements presenting averaged measurements over the measurement cycles. 19

12. The aerosol generation device (10; 210; 310) according to any one of the preceding claims, wherein the control module (43) is configured to extract the control features from the bioimpedance measurements using Fast Fourier Transforms.

13. The aerosol generation device (10; 210; 310) according to any one of the preceding claims, wherein, in a calibration operation mode, the control module (43) is configured to extract control features from the bioimpedance measurements and store these features as reference features.

14. The aerosol generation device (10; 210; 310) according to any one of the preceding claims, wherein, if the user is authenticated, the control module (43) is configured to trigger a normal operation mode of the device (10; 210; 310), otherwise, the control module (43) is configured to trigger a degraded operation mode of the device (10; 210; 310) or deactivate the device (10; 210; 310).

15. Operation method of an aerosol generation device (10; 210; 310) designed to operate according to several operation modes, the operation method comprising:

- generate (130), while the device (10; 210; 310) is handheld by a user, bioimpedance measurements relative to the user’s body bioimpedance;

- extract (132) control features from the bioimpedance measurements;

- compare (134) the control features with reference features and basing on this comparison, authenticate (136) the user.