Patent Application
20230045861
The present solution relates to a device and a method for automatic detection of road conditions for vehicle applications, in particular for autonomous or automated driving.
As is known, road vehicles are commonly provided with a plurality of sensors, in order to increase their safety and also in order to implement autonomous or automated driving.
In this regard, the monitoring and detection of road conditions and consequent forces generated on the vehicle tires/wheels are, for example, crucial to ensure safety and reliability.
In particular, the detection of road conditions (for example, distinguishing between a dry or wet road) may enable to significantly improve the intervention modes of important vehicle systems, such as the braking system, the steering or the active suspensions. Furthermore, the possibility of signaling and warning a driver as to road conditions may significantly improve driving safety.
In general, two approaches have been proposed for monitoring road conditions:
For example, as to the second approach, J. Häkli et al., “Road surface condition detection using 24 GHz automotive radar technology,” 14th International Radar Symposium (IRS), 2013, pp. 702-707, discloses measurement systems using a 24-GHz radar technology to study the backscattering properties of different asphalt surfaces, such as dry, wet or icy surfaces.
I. Abdić et al., “Detecting road surface wetness from audio: A deep learning approach,” 23rd International Conference on Pattern Recognition (ICPR), 2016, pp. 3458-3463, discloses a method for detecting the humidity of the road surface, based on the processing of sound signals generated by the interaction between the same surface and the tire.
E. Šabanovič, et al. “Identification of Road-Surface Type Using Deep Neural Networks for Friction Coefficient Estimation,” Sensors 2020, 20, no. 3, 612, discloses a solution for detecting the type of road surface based on the acquisition of images and their processing through the use of DNN (Deep Neural Network) neural networks.
The present Applicant has found that the solutions currently used have, however, some limitations and suffer from some drawbacks, in general as to the applicability to various operating conditions, the reliability and robustness to external and unwanted factors, the life and reliability of the used sensors.
The present solution is directed to overcoming the drawbacks of the known approaches, providing a solution for detecting road conditions, having improved characteristics.
According to the present solution, a device and a method for the detection of road conditions are provided. A road condition detection device is coupled to a wheel of a vehicle and includes an electrostatic charge variation sensor, configured to provide a charge variation signal indicative of an electrostatic charge variation associated with rotation of the wheel and a processing unit, coupled to the electrostatic charge variation sensor and configured to receive the charge variation signal and further configured to receive a rotation speed signal indicative of the rotation speed of said wheel. The processing unit is configured to jointly process said rotation speed signal and charge variation signal for detecting a road condition between a wet condition and a dry condition in response to an amplitude of the charge variation signal and the rotation speed signal.
For a better understanding of the disclosure, embodiments thereof are now described, purely by way of non-limiting example and with reference to the attached drawings, wherein:
As shown schematically in
The detection device 1 may for example be coupled to the rim of the wheel 2, in proximity to the tire, or be coupled to the tire, or be integrated inside the rim or tire.
As will be discussed in detail below, the detection device 1 is configured so that a charge variation signal provided by the electrostatic charge variation sensor is processed jointly, or in combination, with information on the rotation speed of the wheel, in order to identify road conditions, in particular to distinguish between a dry road condition and a wet road condition.
In a per se known manner, the electric charge is a fundamental component of nature. The charge of an electrostatically charged body may be easily transferred to another body, in conditions of direct contact between the elements or at a distance. When the charge is transferred between two electrically insulated objects, a static charge is generated whereby the object with an excess of electrons is charged negatively and the object with a deficit of electrons is charged positively. The displacement of charges is of a different nature, depending on whether the object is a conductive object or a dielectric. In a conductor, the electrons are distributed throughout the material and are free to move, based on the influence of external electric fields. In a dielectric, there are no electrons free to move but electric dipoles, with random directions in space (thus resulting in zero net charge), which may be oriented or deformed through an external electric field, thus generating an ordered charge distribution and, therefore, a bias. The charge may be movable, depending on material properties and other environmental factors.
In the present solution, the electrostatic charge variation sensor of the detection device 1 is configured to detect, through electrostatic induction, the variations in the electric field (and therefore in electrostatic potential), which occur over time due to the local electrostatic charge variation, caused by the rotation of the wheel 2 of the vehicle 3, to which the same sensor is coupled.
In particular, when, during its rotation, the portion of the wheel 2, at which the charge variation sensor is coupled, comes into contact with the road surface (in particular, asphalt), an electrostatic charge generation (due to triboelectric effect) occurs, with a consequent evident modification in the charge variation signal provided by the charge variation sensor.
In this regard,
In particular, it is evident that, corresponding to the rotations of the wheel 2 (that occur at a shorter period, i.e., at a higher angular frequency, the greater the rotation speed), peaks are generated in the charge variation signal SQ, due to the aforementioned electrostatic charge generation effect caused by the contact between the tire and the road.
In the frequency spectrum of the charge variation signal SQ various harmonics of the rotation frequency of the wheel are present; in particular, the frequency of the main or fundamental harmonic has a value corresponding to the inverse of the rotation period of the wheel 2, i.e., to its rotation speed (indicated in RPS, revolutions per second) and has a significantly greater amplitude; further harmonics are present at multiples of the main harmonic frequency.
The present Applicant has found that the amplitude of the aforementioned charge variation signal SQ is strongly influenced by (and therefore indicative of) the road conditions. In particular, in the presence of water (of a so-called “aqueous film”) on the road surface, this amplitude is significantly lower, due to the fact that electrostatic charge generation due to the triboelectric effect (i.e., due to the rubbing of the tire on the road) is significantly reduced (the wet road condition neutralizing this effect to a significant extent).
In this regard,
From the comparative examination of these
In detail, the present Applicant has found an average reduction in the amplitude of the charge variation signal SQ, considered in the time domain, by a factor of about 100; and a corresponding average reduction in the charge variation signal SQ, considered in the frequency domain, by a factor equal to about 5000.
An aspect of the present solution thus provides for the joint or combined processing of the charge variation signal SQ, in particular considered in the frequency domain (where a more marked reduction in the aforementioned amplitude occurs), and of a signal indicative of the rotation speed of the wheel 2, which is used to identify the fundamental (and most significant) harmonic of the same charge variation signal SQ.
As will be highlighted, according to an aspect of the present solution, this rotation speed variation signal is also used to inhibit the detection of road conditions at reduced rotation speeds of the wheel 2, since the present Applicant has found that, for reduced speeds, the aforementioned electrostatic charge generation associated with the rotation of the wheel 2 may not be significant and therefore not provide reliable indications.
In particular, in a possible embodiment, the aforementioned rotation speed sensor 12 is a semiconductor gyroscope made using MEMS (Micro Electro Mechanical System) technology, of a per se known type and not described in detail herein, which is configured to provide a rotation speed (or angular speed) signal SV, expressed in degrees/sec;
an electrostatic charge variation sensor 14, configured to provide a charge variation signal SQ indicative of an electrostatic charge variation; and
a processing unit 16, coupled to the rotation speed sensor 12 and to the electrostatic charge variation sensor 14 in order to receive the rotation speed signal SV and the charge variation signal SQ and configured to jointly process the aforementioned rotation speed signal SV and charge variation signal SQ to detect road conditions and output information on detected road condition.
In a manner not illustrated herein, these road condition information may be sent, for example through a wireless transmission, to a management and control unit of the vehicle 3 having the detection device 1 incorporated therein, in order to perform and activate certain actions in response to the road condition detection (for example, activating suitable adjustments of one or more systems of the vehicle 3, such as a braking system, suspensions or steering).
In greater detail, the aforementioned processing unit 16 comprises for example a microcontroller, or an MLC (Machine Learning Core) processor resident in an ASIC (Application Specific Integrated Circuit) electronic circuit coupled to the rotation speed sensor 12 and to the electrostatic charge variation sensor 14 for processing the corresponding rotation speed signal SV and charge variation signal SQ; the aforementioned rotation speed sensor 12, electrostatic charge variation sensor 14 and processing unit 16 may be integrated within a same package (or chip) provided with suitable elements for electrical connection to the outside.
In a possible implementation, the aforementioned chip may be coupled to a printed circuit board (not illustrated here), and a wireless communication module (also not illustrated) may be coupled to the same printed circuit board, for remote transmission, for example to the aforementioned management and control unit of the vehicle 3, of the road condition information provided by the detection device 1.
The detection electrode IN, in the illustrated exemplary solution, forms part of a differential input 19 of an instrumentation amplifier 22, being coupled to a corresponding first input terminal 19a.
An input capacitor CI and an input resistor RI are connected in parallel with each other between the first input terminal 19a and a second input terminal 19b of the differential input 19.
During operation, an input voltage Vd across the input capacitor CI varies due to the charge redistribution in the external environment. After a transient (whose duration is given by the constant RI·CI defined by the parallel between the capacitor CI and the resistor RI), the input voltage Vd returns to its steady state value (so-called “steady state”).
The instrumentation amplifier 22 is essentially made by two operational amplifiers OP1 and OP2, having non-inverting input terminals connected to the first and to the second input terminals 19a, 19b, respectively, and inverting terminals connected to each other through a gain resistor RG2.
A biasing stage (buffer) OP3 biases the instrumentation amplifier 22 to a common mode voltage VCM, through a resistor R1 coupled to the second input terminal 19b.
The output terminals of the operational amplifiers OP1 and OP2 are connected to the respective inverting input terminals through a respective gain resistor RG1; an output voltage Vd′ is present between the same output terminals.
As will become apparent from the examination of the circuit, the gain Ad of the instrumentation amplifier 22 is equal to (1+2·R1/R2); therefore, the aforementioned output voltage Vd′ is equal to: Vd·(1+2·R1/R2).
The components of the instrumentation amplifier 22 are chosen such that the same instrumentation amplifier 22 has a reduced noise and a high impedance (for example of the order of 109 Ohm) in its passband (for example comprised between 0 and 500 Hz).
The aforementioned output voltage Vd′ is input to an analog-to-digital converter (ADC) 24, which outputs the aforementioned charge variation signal SQ for the processing unit 16. This charge variation signal SQ may be, for example, a (16 or 24 bit) high resolution digital stream.
According to a different embodiment, having an analog-to-digital converter 24 with suitable characteristics (e.g., differential input, high input impedance, high resolution, dynamic range optimized for the quantities to be measured, low noise) the instrumentation amplifier 22 may be omitted, in this case supplying the input voltage Vd directly to the input of the analog-to-digital converter 24.
In a manner not illustrated, the charge variation signal SQ may be provided to a first input of a multiplexer block, which may also receive, at at least one further input, the aforementioned rotation speed signal SV (and possibly, at further inputs, further detection signals). The output of the multiplexer block is, in this case, coupled to an input of the processing unit 16, providing the aforementioned charge variation signal and rotation speed signal SQ, SV (and possibly further detection signals) for processing by the same processing unit 16.
As will now be described, this joint processing provides two processing channels executed in parallel and continuously over time, a first channel dedicated to the charge variation signal SQ and a second channel dedicated to the rotation speed signal SV.
In detail, the processing unit 16 is initially configured to acquire, block 30, the charge variation signal SQ(t) in the time domain; in particular, corresponding samples thereof are acquired at subsequent time instants (for example, these samples are stored in an acquisition buffer which is progressively fed with and updated by the same samples).
The aforementioned charge variation signal SQ(t) may be subjected to a normalization operation, for example by removing a corresponding base value, so-called “baseline” (due for example to an environmental electrostatic charge or to an uncompensated offset of the sensor), as indicated in block 32.
The resulting signal is then provided to a frequency transform, block 33, for example through known FFT (Fast Fourier Transform) operations preceded by a windowing operation (for example through a Hann window), to obtain, as indicated in block 34, a charge variation signal SQ(f) in the frequency domain.
Then, block 35, an operation for identifying the peaks in the frequency domain in the charge variation signal SQ(f) is performed, to obtain, as indicated in block 36, a series of N identified peaks, [Pk1, . . . , PkN], each at an associated frequency.
In parallel to the processing of the aforementioned charge variation signal SQ, which in any case continues over time, as indicated in the same
In the illustrated embodiment, this rotation speed sensor 14 is a gyroscope having three detection axes, which provides three angular speed components Gx, Gy, Gz along three detection axes.
In detail, block 38, the aforementioned angular speed components Gx, Gy, Gz are acquired and the modulus G thereof is obtained, block 39 (expressed in degrees per second).
As a function of this modulus, as indicated in block 40, the rotation speed value of the wheel 2 is obtained, expressed in rotations per second, RPS (for example, the aforementioned modulus is divided by 360 to obtain this rotation speed value, RPS).
According to an aspect of the present solution, block 41, the rotation speed value RPS is then compared to a minimum-speed threshold RPSTH, for example corresponding to a speed of the vehicle 3 equal to 4-5 Km/h, in such a way as not to continue with the detection algorithm in case the aforementioned rotation speed value RPS is not higher than the minimum-speed threshold RPSTH.
If, on the other hand, the aforementioned threshold condition is verified (that is, the rotation speed value RPS is higher than the minimum-speed threshold RPSTH), the algorithm continues to block 42, where distances in the frequency domain (in absolute value) are determined between each of the previously detected peaks ([Pk1, . . . , PkN]) and the frequency corresponding to the aforementioned rotation speed RPS (as previously indicated, the value of this rotation speed RPS corresponds in fact to the fundamental frequency of the charge variation signal SQ(f)); the aforementioned distances are indicated with ([d1, . . . , dN]).
In the next block 43, of all the peaks the one with minimum distance dm with respect to the rotation speed value RPS is then selected, the amplitude of this selected peak being indicated with Pkm, as shown in block 44.
The aforementioned minimum distance dm is then compared with a minimum-distance threshold dTH, block 45.
In case the minimum distance dm is less than the minimum-distance threshold dTH, a further comparison between the aforementioned selected peak amplitude Pkm and a peak-amplitude threshold PkTH (whose value may for example be set in the design step or be adjustable, selectable, by an operator to adapt to various use scenarios), is performed, block 46.
In case the selected peak amplitude Pkm is greater than the peak-amplitude threshold PkTH, the algorithm determines the presence of a dry road condition, “dry,” as indicated in block 47.
Otherwise, as indicated in block 48, in case the minimum distance dm is not less than the minimum-distance threshold dui (at the aforementioned block 45), or the selected peak amplitude Pkm is not greater than the peak-amplitude threshold PkTH (at the aforementioned block 46), the algorithm determines the presence of a wet road condition, “wet,” as indicated in block 48.
It should be noted that the aforementioned wet road condition is characterized by the presence of liquid, in particular an aqueous film or layer, on the surface in contact with the wheel 2, which, instead, is not present in the dry road condition.
As shown in the same
In a possible implementation, not illustrated, the count of the time during which a certain condition persists may also be provided, in order to validate the detected condition only if this condition persists for more than a minimum time: for example, for an asphalt to be identified as dry, the system may provide for the detection of the “dry” condition, continuously, for at least five seconds (or other time interval of suitable value).
Basically, the algorithm implemented by the processing unit 16 provides, therefore, for the parallel acquisition of the rotation speed signal SV (advantageously provided by the rotation speed sensor 12, in this case a triaxial gyroscope, so as to correspond directly to the number of rotations or revolutions per second of the wheel 2, therefore to the fundamental frequency at which the pulses of the charge variation signal SQ occur) and of the same charge variation signal SQ provided by the charge variation sensor 14.
On the basis of this charge variation signal SQ, a search for peaks in the spectrum SQ(f) is performed to identify the positions and amplitudes of all detected peaks.
If the aforementioned rotation speed value RPS is greater than the minimum-speed threshold RPSTH, i.e., if the vehicle moves with a speed being greater than the minimum significant speed, the algorithm searches for the peak in the spectrum SQ(f) having minimum distance from the fundamental frequency, which corresponds to the same value RPS.
If a peak with a distance not greater, in absolute value, than the minimum-distance threshold dui is identified and it is also verified that this peak has an amplitude being greater than the peak-amplitude threshold PKTH, then the aforementioned “dry road” condition is determined; otherwise, the aforementioned “wet road” condition is determined.
The amplitude of the charge variation signal SQ is dimensionless expressed as LSB (“Least Significant Bit”), that is the minimum digital value output from the analog-to-digital converter, which is proportional to the voltage detected at the aforementioned input electrode IN (refer again to what has been discussed with reference to
In particular,
The vehicle 3 also comprises a main controller 52 (a microcontroller, a microprocessor or a similar digital processing unit), coupled to the processing unit 16 of the detection device 1, in order to receive information relating to the detected road condition.
In the previously described embodiment, the main controller 52 receives, for example from the processing unit 16 of the detection device 1, the information of “dry road” or “wet road” condition, to activate or deactivate certain adjustments of the same vehicle 3, as previously described, for example of a corresponding braking system, of the steering or of the suspensions.
The advantages that the present solution allows to achieve are clear from the preceding description.
In any case, it is highlighted that the detection device 1:
The detection device 1 also has an optimized energy consumption (the consumption associated with the aforementioned rotation speed sensor 12 and charge variation sensor 14 and with the corresponding electronics is very low) and a reduced space occupation (in particular, with the possibility of integrating both the detection, rotation speed and charge variation technologies in a single package).
In this regard, and as previously indicated, the use of a MEMS gyroscope as the aforementioned rotation speed sensor 12 is particularly advantageous (in this case, in fact, the frequency of the fundamental harmonic of the charge variation signal SQ is equal to the inverse of the rotation period of the wheel 2, i.e., to the RPS value which is calculated directly from the output of the same gyroscope), according to the expression:
RPS=DPS/360,
where DPS (Degrees Per Second) corresponds to the modulus of the angular speed vector (considering the three detection axes).
Finally, variations and modifications may be applied to the present solution, without thereby departing from the scope identified by the claims.
For example, in a manner not illustrated, a plurality of the aforementioned charge variation sensors 14 might be used, possibly coupled to the different wheels 2 of the vehicle 3 and/or coupled, in a certain number, to each of these wheels 2, in order to further increase the reliability and accuracy of the determination of road conditions (for example, by averaging or processing in a suitable manner, the indications provided by the various sensors).
Similarly, the system might provide for the use of a plurality of rotation speed sensors 12, again for example coupled to each of the wheels 2 of the vehicle 3.
The aforementioned rotation speed sensor 12 might be a different sensor, for example a monoaxial or biaxial gyroscope, or a different sensor configured in any case to provide the information on the rotation speed of the wheel 2.
Furthermore, variants of the present solution might allow distinguishing, in addition to the two extreme conditions “dry” (absence of a significant amount of liquid) and “wet” (presence of a significant amount of liquid), also different and further conditions, after a suitable calibration of the detection device 1, taking into account, for example, factors such as the type of tread of the wheel 2 and the material thereof, the state of wear, the type of road surface, etc.
It is highlighted that the present solution may find advantageous application for any road vehicle, in particular a motor car, but also a motor vehicle or other kind of vehicle (bicycles, mopeds, etc.) provided with wheels in contact with the road (in a material, for example rubber, being suitable for the described electrostatic charge generation).
Furthermore, it is again highlighted that the detection device 1 may be made in a single chip that incorporates the charge variation sensor 14 (and the electronic circuitry thereof), the rotation speed sensor 12 and the processing unit 16; alternatively, the charge variation signal SQ and the rotation speed signal SV could be processed in the main controller 52 of the vehicle 3 having the detection device 1 incorporated therein (implementing in this case the aforementioned processing unit 16).
Furthermore, it is highlighted that the input electrode IN (or detection electrode) of the electrostatic charge variation sensor 14 might also be a simple conductive probe; a metal plane or path in the printed circuit board; or any conductive element that may operate as a detection electrode for being arranged facing the operating environment associated with the rotation of the wheel 2 of the vehicle 3, in order to detect the charge variation.
A road condition detection device (1), configured to be coupled to the wheel (2) of a vehicle (3) and may be summarized as including an electrostatic charge variation sensor (14), configured to provide a charge variation signal (SQ) indicative of an electrostatic charge variation associated with the rotation of said wheel (2); and a processing unit (16), coupled to the electrostatic charge variation sensor (14) to receive the charge variation signal (SQ) and further configured to receive a rotation speed signal (SV) indicative of the rotation speed of said wheel (2), wherein said processing unit (16) is configured to jointly process said rotation speed signal (SV) and charge variation signal (SQ) for detecting a road condition.
Said processing unit (16) may be configured to determine one of a dry road condition and a wet road condition.
The device may further include a rotation speed sensor (12), configured to provide said rotation speed signal (SV).
Said rotation speed sensor (12) may be a MEMS triaxial gyroscope; and said processing unit (16) may be configured to determine said rotation speed of the wheel (2) as a function of the modulus of an angular speed signal provided by said gyroscope.
Said charge variation sensor (12) may include at least one detection electrode (IN) configured to detect said electrostatic charge variation; a high-impedance instrumentation amplifier (22) having an input coupled to said detection electrode (IN); and an analog-to-digital converter (24) coupled to the output of said instrumentation amplifier (22) to provide said charge variation signal (Se).
Said processing unit (16), said rotation speed sensor (12) and said electrostatic charge variation sensor (14) may be integrated within a same chip.
Said processing unit (16) may be configured to: determine, in the trend in the frequency domain of said charge variation signal (Se), a peak amplitude of a fundamental frequency at said rotation speed of the wheel (2); and compare said peak amplitude with a threshold amplitude (PkTH) to determine one of a dry road condition and a wet road condition.
Said processing unit (16) may be configured to: determine a frequency distance between said fundamental frequency and a frequency associated with said rotation speed of the wheel (2); and compare said distance with a threshold distance (dTH) to determine said one of a dry road condition and a wet road condition.
Said processing unit (16) may be configured to determine the dry road condition in case said distance is less than the threshold distance (dTH) and said peak amplitude is greater than the threshold amplitude (PkTH); and determine the wet road condition in case said distance is not less than the threshold distance (dTH) or said peak amplitude is not greater than the threshold amplitude (PKTH).
Said processing unit (16) may be configured to: perform a transform in the frequency domain to obtain the charge variation signal in the frequency domain; perform a peak identification operation in the frequency domain in the charge variation signal, to obtain a series of identified peaks, each at an associated frequency; determine the frequency distances between each of the detected peaks and a frequency corresponding to the rotation speed of the wheel (2); select the peak with minimum distance (dm) with respect to said frequency corresponding to the rotation speed of the wheel (2) and determine the amplitude of said selected peak as said peak amplitude of the fundamental frequency.
Said processing unit (16) may be configured to: compare said rotation speed with a minimum-speed threshold (RPSTH); and continue the detection of said road conditions only in case said rotation speed value is higher than said minimum-speed threshold (RPSTH).
A vehicle system, may be summarized as including a detection device (1) and a main controller (52) coupled to the processing unit (16) of the detection device (1), in order to receive information on road condition, for executing and/or activating certain actions according to said road condition.
A method for detecting road conditions for a vehicle (3) having at least one wheel (2), may be summarized as including generating, by an electrostatic charge variation sensor (14), a charge variation signal (Se) indicative of an electrostatic charge variation associated with the rotation of said wheel (2); and receiving, by a processing unit (16) coupled to the electrostatic charge variation sensor (14), the charge variation signal (SQ) and a rotation speed signal (SV) indicative of the rotation speed of said wheel (2), further including, by said processing unit (16), jointly processing said rotation speed signal (SV) and charge variation signal (SQ) to detect a road condition.
Detecting may include determining one of a dry road condition and a wet road condition.
Processing may include: determining, in the trend in the frequency domain of said charge variation signal (SQ), the peak amplitude of a fundamental frequency at said rotation speed of the wheel (2); and comparing said peak amplitude with a threshold amplitude (PkTH) to determine one of a dry road condition and a wet road condition.
Processing may include: determining a frequency distance between said fundamental frequency and a frequency associated with said rotation speed of the wheel (2); and comparing said distance with a threshold distance (dTH) to determine said one of a dry road condition and a wet road condition.
The method may include: determining the dry road condition in case the distance is less than said threshold distance (dTH) and the peak amplitude is greater than said threshold amplitude (PkTH); and determining the wet road condition in case the distance is not less than said threshold distance (dTH) or the peak amplitude is not greater than said threshold amplitude (PKTH).
Processing may include: performing a transform in the frequency domain to obtain the charge variation signal in the frequency domain; performing a peak identification operation in the frequency domain in the charge variation signal, to obtain a series of identified peaks, each at an associated frequency; determining the frequency distances between each of the detected peaks and the frequency corresponding to the rotation speed of the wheel (2); selecting the peak with minimum distance (dm) with respect to said rotation speed value and determine the amplitude of said selected peak as said peak amplitude of the fundamental frequency.
The method may include: comparing said rotation speed value with a minimum-speed threshold (RPSTH); and continuing the detection of said road conditions only in case said rotation speed value is higher than a minimum-speed threshold (RPSTH).
The method may include implementing the execution and/or activation of certain actions in said vehicle (3) according to the detection of said road conditions.
The various embodiments described above can be combined to provide further embodiments. Aspects of the embodiments can be modified, if necessary to employ concepts of the various patents, applications and publications to provide yet further embodiments.
These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102021000021680 | Aug 2021 | IT | national |
