Patent Publication Number: US-11656071-B2

Title: Electronic apparatus control method performed through lid angle calculation, electronic apparatus thereof and software product

Description:
BACKGROUND 
     Technical Field 
     The present disclosure relates to an electronic apparatus control method performed via calculation of an angle of lid opening, to an electronic apparatus thereof and to a software product. 
     Description of the Related Art 
     As illustrated in  FIG.  1   , a portable device  1  of a known type (e.g., a notebook) is typically formed by two functional blocks  2 ,  4 , where the functional block  2  accommodates a screen  2   a  and the functional block  4  accommodates a keypad  4   a  and the control unit and memory  4   b ,  4   c . The functional blocks  2  and  4  are coupled together by a pivot  6 , configured for enabling a rotary movement of the functional block  2  with respect to the functional block  4 . An angle α LID , known as opening angle or by the term “lid angle”, is formed between the functional block  2  (i.e., at the screen  2   a ) and the functional block  4  (i.e., at the keypad  4   a ). For instance, the angle α LID  is formed between respective surfaces of the functional block  2  and of the functional block  4 . By convention, the angle α LID  is equal to 0° when the surface of the functional block  4  is parallel to and directly facing the surface of the functional block  2 ; and is equal to 360° when the surface of the functional block  4  is parallel to the surface of the functional block  2  but oriented in the opposite direction. 
     The measurement of the angle α LID  enables, for example, adaptation or modification of a user interface displayed by the screen  2   a  in order to improve user experience of the portable device  1 . 
     Moreover, it is desirable to measure the angle α LID  in portable devices such as tablets, foldable smartphones, and portable devices to which external keypads are operatively coupled (for example, integrated in a cover of the portable device and connected to the portable device by means of a wireless connection) in order to adapt or personalize the user interface or the configuration of the portable device and make available new possibilities of use thereof. 
     Known solutions for detecting the angle α LID  envisage the use of an accelerometer mounted on the functional block  2  and of an accelerometer mounted on the functional block  4 . Said accelerometers supply data indicating the direction of the force of gravity with respect to respective systems of co-ordinates centered on the accelerometers themselves, thus making it possible to identify a position of the functional block  2  with respect to the functional block  4 . However, this solution, being based exclusively upon the information deriving from the force gravity, does not make it possible to provide indications useful for all the possible orientations and arrangements in space of the portable device  1 . In fact, this solution does not enable a reliable measurement if the portable device  1  is oriented with the pivot  6  parallel to the direction of the force of gravity (i.e., vertical position, or book-like position, of the portable device  1 ). Furthermore, the accelerometers are subject to environmental vibrational stimuli that may cause the measurement to be imprecise or wrong. In particular, given that accelerometers are sensitive to linear accelerations, the measurement of the angle α LID  is unreliable when the portable device is moving or else is subjected to external vibrations, for example when a person who is carrying the portable device is walking or is travelling in a means of transport. It is possible to use a filter (e.g., a lowpass filter) for reducing the effect of the linear accelerations on the measurement of the angle α LID , but this increases the response time in estimation of the angle α LID . 
     The patent document EP3407157 discloses a portable device analogous to the one illustrated in  FIG.  1   , where each functional block further includes a respective gyroscope. Gyroscopes are used in order to improve the reactivity of the measurement of the angle α LID  and to enable, through a data-fusion approach, said measurement to be made even when the portable device is rotated in the vertical position. 
     BRIEF SUMMARY 
     In various embodiments, the present disclosure provides an electronic apparatus control method performed through lid angle calculation, an electronic apparatus thereof and a software product that overcome the drawbacks of the prior art. 
     According to the present disclosure an electronic apparatus control method performed through lid angle calculation, an electronic apparatus thereof and a software product are provided. 
     In at least one embodiment, a method is provided for controlling at least one function of an electronic apparatus as a function of a value of a lid angle between a first hardware element and a second hardware element of the electronic apparatus. The first hardware element accommodates a first magnetometer and the second hardware element accommodates a second magnetometer and is orientable with respect to the first hardware element. The method includes: generating, by the first magnetometer and by the second magnetometer, first signals that are indicative of measurements of a magnetic field external to the electronic apparatus and are indicative of a relative orientation of the first hardware element with respect to the second hardware element; acquiring, by a processing unit of the electronic apparatus, the first signals; generating, by the processing unit and as a function of the first signals, a calibration parameter indicative of a condition of calibration of the first and second magnetometers; generating, by the processing unit and as a function of the first signals, a reliability value indicative of a condition of reliability of the first signals; calculating, by the processing unit, a first intermediate value of the lid angle based on the first signals; calculating, by the processing unit, a current value of the lid angle based on the calibration parameter, the reliability value, and the first intermediate value of the lid angle; and controlling the function of the electronic apparatus as a function of the current value of the lid angle. 
     In at least one embodiment, an electronic apparatus is provided that includes a first hardware element, a second hardware element, and a processing unit. The first hardware element accommodates a first magnetometer. The second hardware element accommodates a second magnetometer, orientable with respect to the first hardware element, and defining a lid angle with the first hardware element. The first and second magnetometers are configured for generating first signals that are measurements of a magnetic field external to the electronic apparatus and are indicative of a relative orientation of the first hardware element with respect to the second hardware element. The processing unit is configured to: acquire the first signals; generate, as a function of the first signals, a calibration parameter indicative of a condition of calibration of the first and second magnetometers; generate, as a function of the first signals, a reliability value indicative of a condition of reliability of the first signals; calculate a first intermediate value of the lid angle based on the first signals; calculate a current value of the lid angle based on the calibration parameter, of the reliability value, and the first intermediate value of the lid angle; and control the function of the electronic apparatus as a function of the current value of the lid angle. 
     In at least one embodiment, a non-transitory computer-readable medium is provided having contents which cause processing circuitry of an electronic apparatus to perform a method. The electronic apparatus includes a first hardware element accommodating a first magnetometer, and a second hardware element accommodating a second magnetometer, orientable with respect to the first hardware element, and defining a lid angle with the first hardware element, wherein the first and second magnetometers are configured for generating first signals that are measurements of a magnetic field external to the electronic apparatus and are indicative of a relative orientation of the first hardware element with respect to the second hardware element. The method includes: acquiring the first signals; generating, as a function of the first signals, a calibration parameter indicative of a condition of calibration of the first and second magnetometers; generating, as a function of the first signals, a reliability value indicative of a condition of reliability of the first signals; calculating a first intermediate value of the lid angle based on the first signals; calculating a current value of the lid angle based on the calibration parameter, the reliability value, and the first intermediate value of the lid angle; and controlling the function of the electronic apparatus as a function of the current value of the lid angle. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       For a better understanding of the present disclosure, a preferred embodiment thereof is now described purely by way of non-limiting example, with reference to the attached drawings, wherein: 
         FIG.  1    is a schematic perspective view of a portable device, in particular a notebook, configured for enabling calculation of an opening angle of the screen with respect to the keypad, according to an embodiment of a known type; 
         FIG.  2    is a schematic perspective view of a portable device, in particular a notebook, provided with magnetometers configured for enabling calculation of an opening angle of a screen with respect to a keypad, according to one embodiment; 
         FIG.  3    is a side view of the portable device of  FIG.  2   , in three operative conditions alternative to one another; 
         FIGS.  4 A- 4 B  are schematic perspective views of the portable device of  FIG.  2    in respective further operative conditions; 
         FIG.  5    is a schematic illustration of functional blocks implemented by the portable device of  FIG.  2   , according to an embodiment of the present disclosure; 
         FIG.  5 A  is a schematic illustration of functional blocks included in one of the functional blocks of  FIG.  5   , according to an embodiment of the present disclosure; 
         FIG.  6    is a schematic perspective view of a portable device, in particular a notebook, provided with magnetometers and accelerometers configured for enabling calculation of an opening angle of a screen with respect to a keypad, according to a different embodiment; 
         FIG.  7    is a schematic illustration of functional blocks implemented by the portable device of  FIG.  6   , according to an embodiment of the present disclosure; 
         FIG.  8    is a schematic perspective view of a portable device, in particular a notebook, provided with magnetometers and gyroscopes configured for enabling calculation of an opening angle of a screen with respect to a keypad, according to a further embodiment; and 
         FIG.  9    is a schematic illustration of functional blocks implemented by the portable device of  FIG.  8   , according to an embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Elements and steps common to different embodiments of the present disclosure are designated hereinafter by the same reference numbers. 
     With reference to  FIG.  2   , according to one aspect of the present disclosure, an electronic apparatus (in particular, a portable device)  10  is illustrated in a triaxial cartesian reference system XYZ defined by the axes X, Y and Z. In the reference system XYZ, a vector g (or acceleration vector g), which represents the gravity acceleration vector acting in a direction parallel to the axis Z and having an opposite orientation with respect thereto, and a vector B, which represents the Earth&#39;s magnetic field vector (hereinafter, magnetic field B or magnetic-field vector B), are considered. According to an aspect of the present disclosure, the magnetic field B acts in a plane YZ defined by the axes Y, Z, and in particular forms with the axis Y an inclination angle δ, for example equal to about 45°, and forms with the acceleration vector a respective angle, for example equal to the angle of inclination  6 . 
     The device  10  is of a portable type (in particular, a notebook) and is here represented in an operative condition of open device. The portable device  10  includes a lid portion  12  and a base portion  14 , mechanically coupled to each other by means of a hinge  15 , which enables rotation of the lid portion  12  with respect to the base portion  14 , forming a rotation constraint about a rotation axis R (or axis R), in  FIG.  2    represented by way of example parallel to the axis X. The base portion  14  comprises at least one interface device  16  (e.g., a keypad and/or a trackpad), extending at a surface  14   a  of the base portion  14 . The lid portion  12  comprises a display region  18  (e.g., a screen or monitor), extending at a surface  12   a  of the lid portion  12 . In an operative condition of closed device, the surfaces  12   a ,  14   a  face one another. The lid portion  12  accommodates (e.g., integrates within it) a first magnetometer  20  configured for detecting and/or calculating the orientation, along respective sensing axes x 1 , y 1 , z 1 , of the lid portion  12  with respect to the magnetic field B; and the base portion  14  accommodates (e.g., integrates within it) a second magnetometer  22 , configured for detecting and/or calculating the orientation, along respective sensing axes x 2 , y 2 , z 2 , of the base portion  14  with respect to the magnetic field B. The first and second magnetometers  20 ,  22  are configured for generating a first magnetic-field signal (hereinafter, first signal B 1 ) and, respectively, a second magnetic-field signal (hereinafter, second signal B 2 ). In general, the first and second magnetometers  20 ,  22  are configured to detect a change of orientation of the portable device  10  by means of measurements of the magnetic field B. The first and second magnetometers  20 ,  22  are, for example, magnetometers obtained with MEMS technology (e.g., MEMS magnetometers based upon AMR, Anisotropic MagnetoResistance, technology). In particular, the first signal B 1  is indicative of the components of the magnetic field B along the sensing axes x 1 , y 1 , z 1 , and the second signal B 2  is indicative of the components of the magnetic field B along the sensing axes x 2 , y 2 , z 2 . 
     It is here pointed out that, in the embodiment of the portable device  10  here considered, the axis R of the hinge  15  is always parallel to the sensing axes x 1 , x 2  in any operative condition (lid portion  12  closed or open) and for any orientation of the device  10  in the triaxial reference system XYZ. 
     The portable device  10  further comprises a processing unit that includes a microcontroller or control unit  27  and a memory  28 , coupled together. The control unit  27  and/or the memory  28  are moreover operatively coupled to the first and second magnetometers  20 ,  22  for receiving therefrom the respective signals B 1 , B 2 , generated according to operation in itself known of magnetometers. The signals B 1 , B 2  received at input from the control unit  27  are processed as better described hereinafter with reference to  FIG.  5   . 
     In particular, the first and second magnetometers  20 ,  22  are configured to detect the variation of a mutual orientation between the lid portion  12  and the base portion  14  (for example, due to opening and closing, with respect to the base portion  14 , of the lid portion  12  turning about the axis R due to the hinge  15 ). In this latter case, in particular, the first and second magnetometers  20 ,  22  are used for determining an opening angle α LID , supplementary to an angle between the sensing axis y 1  and the sensing axis y 2  of the respective first and second magnetometers  20 ,  22 . The opening angle α LID  is therefore correlated to the angle existing between the surface  12   a  of the lid portion  12  and the surface  14   a  of the base portion  14  and is also known as “lid angle”. In use, it is possible to correlate the value of the lid angle α LID  with a use mode of the portable device  10  (e.g., a lid angle α LID  having a value of about 130° suggests a laptop-use mode, whereas a lid angle α LID  having a value of 360° suggests a tablet-use mode. It is therefore possible to adapt the graphic interface represented in the display region  18  to the type of operating mode, or else adapt other operating parameters of the portable device  10 , for example enabling a touchscreen function when the tablet-use mode is detected, or vary other parameters still, such as switching-on/switching-off of the display region  18  or of the portable device  10  if the value the lid angle α LID  is greater/less than a certain threshold. 
       FIG.  3    illustrates, in lateral view in the plane YZ, the portable device  10  of  FIG.  2   , where the lid portion  12  is represented in three possible operative conditions S1-S3: lid portion  12  closed on the base portion  14 , defining a lid angle α LID  of zero value (S1); lid portion  12  defining a lid angle α LID  of 90° with respect to the base portion  14  (S2); and lid portion  12  defining a lid angle α LID  of 180° with respect to the base portion  14  (S3). 
     In the operative conditions S1-S3, the lid angle α LID  is the relative angle between the sensing axis y 1  and the sensing axis y 2  of the magnetometers  20  and  22  (in detail, between the positive semi-axis of the axis y 1  and the negative semi-axis of the axis y 2 ) and, since it has been assumed that said sensing axes y 1 , y 2  are parallel to the surfaces  12   a ,  14   a  of the lid portion  12  and the base portion  14 , the lid angle α LID  is also the relative angle between the surfaces  12   a ,  14   a  of the lid portions  12  and the base portion  14 . In other words, the lid angle α LID  coincides with the opening angle (or lid angle) of the lid portion  12  with respect to the base portion  14 . The same angular quantity may likewise be defined between the axes z 1  and z 2  (in detail, between the positive semi-axis of the axis z 1  and the negative semi-axis of the axis z 2 ), which are always normal to the surfaces  12   a ,  14   a.    
     Passing from the operative condition S1 to the operative condition S2 (or likewise from the operative condition S2 to the operative condition S3), the first magnetometer  20  detects a variation of the components of the magnetic field B along the axes z 1  and y 1 , and this makes it possible to determine the fact that the lid angle α LID  increases (whereas the opposite is true, in the passage from the condition S2 to the condition S1, or from the condition S3 to the condition S2). 
     It may, in particular, be noted that the magnetic field B is given, in the operative condition S1, by first values detected on the axes y 1 , z 1  and, in the operative condition S2, by second values detected on the axes y 1 , z 1 , said second values being different from the first values. 
     In order to calculate a value of the lid angle α LID , it is possible to exploit the projection of the magnetic field B on the respective three sensing axes of the first and second magnetometers  20 ,  22 , taking into consideration the constraints due to the presence of the hinge  15 . In this case, a value α LID_MAG  of the angle α LID  calculated via the magnetometers  20 ,  22  is obtained by applying the following expression: 
                     α     LID   ⁢           ⁢   _   ⁢           ⁢   MAG       =       arctan   ⁢           ⁢   2   ⁢     (         G   ⁢       z   2     ·     Gy   1         -       Gy   2     ·     Gz   1             G   ⁢       z   2     ·     Gz   1         +     G   ⁢       y   2     ·     Gy   1             )       +     π   ⁡     (   rad   )                 (   1   )               
where arctan 2 is the known trigonometric function, Gz 1  is the component of the magnetic field B detected by the first magnetometer  20  along the sensing axis z 1 , Gy 1  is the component of the magnetic field B detected by the first magnetometer  20  along the sensing axis y 1 , Gz 2  is the component of the magnetic field B detected by the second magnetometer  22  along the sensing axis z 2 , and Gy 2  is the component of the magnetic field B detected by the second magnetometer  22  along the sensing axis y 2 . As represented by Eq. (1), the value α LID_MAG  measured via the magnetometers  20 ,  22  represents a relative orientation (i.e., an orientation that is not absolute in space) between the lid portion  12  and the base portion  14 .
 
       FIG.  4 A  shows a mode of use of the portable device  10  where the portable device  10  is oriented with the axis R parallel to the magnetic-field vector B. In this case, passage into the operative conditions S1-S2-S3 does not cause a variation of the component of magnetic field B along the sensing axes z 1 , z 2 , and y 1 , y 2  of the first and second magnetometers  20 ,  22 , since the components of the magnetic field B along the axes referred to are always zero or substantially zero (i.e., the values Gz 1 , Gz 2 , Gy 1 , Gy 2  of Eq. (1) are approximately equal to zero). Consequently, in this situation the value α LID_MAG  cannot be calculated accurately. What has been described with reference to  FIG.  4 A  may be applied, in a way in itself obvious, also to the operative condition (not illustrated) where the portable device  10  is oriented with the axis R parallel to the magnetic-field vector B, but rotated through 180° with respect to the orientation shown in  FIG.  4 A . 
     With reference to  FIG.  4 B  an intermediate situation of orientation is shown, where the axis R forms with the magnetic-field vector B a reliability angle φ other than 0° and smaller than or equal to 90°. These intermediate situations of orientation lead to measurements of the value α LID_MAG  that are all the more erroneous, the more closely they approach the condition of  FIG.  4 A  (axis R parallel to the magnetic-field vector B), i.e., the closer the reliability angle φ is to 0°. 
     In operative conditions where the sensing axes x 1  and x 2  are parallel to the magnetic field B and the sensing axes y 1  and y 2  are perpendicular to the magnetic field B ( FIG.  4 A ), the components Gx 1  and Gx 2  have a maximum value, and the components Gy 1  and Gy 2  have a minimum value; instead, in operative conditions where the sensing axes x 1  and x 2  are perpendicular to the magnetic field B and the sensing axes y 1  and y 2  are parallel to the magnetic field B, the components Gx 1  and Gx 2  have a minimum value and the components Gy 1  and Gy 2  have a maximum value (the minimum and maximum values depend upon the type of inertial sensor used and are defined by the manufacturer). 
     The reliability of the calculation of the value α LID_MAG  is therefore correlated to a first reliability angle φ 1 , which represents the measurement of the reliability angle φ made via the magnetometers  20 ,  22 . 
     According to an aspect of the present disclosure, a first angle φ a  is calculated via the first magnetometer  20  according to the following expression: 
     
       
         
           
             
               
                 
                   
                     φ 
                     a 
                   
                   = 
                   
                     
                       tan 
                       
                         - 
                         1 
                       
                     
                     ⁢ 
                     
                       
                         
                           
                             G 
                             ⁢ 
                             
                               y 
                               1 
                               2 
                             
                           
                           + 
                           
                             G 
                             ⁢ 
                             
                               z 
                               1 
                               2 
                             
                           
                         
                       
                       
                          
                         
                           Gx 
                           1 
                         
                          
                       
                     
                     ⁢ 
                     
                       ( 
                       rad 
                       ) 
                     
                   
                 
               
               
                 
                   ( 
                   2 
                   ) 
                 
               
             
           
         
       
     
     The first angle φ a  therefore varies between 0° and 90°. Likewise, a second angle φ b  is calculated via the second magnetometer  22 . 
     The first reliability angle φ 1  is correlated to the first angle φ a  and/or the second angle φ b . According to one aspect of the present disclosure, the first reliability angle φ 1  is equal to the first angle φ a  or to the second angle φ b ; according to a different aspect of the present disclosure, the first reliability angle φ 1  is equal to an average (alternatively, a weighted average) of the first and second angles φ a , φ b . 
     If the first reliability angle φ 1  is greater than a threshold angle φ th , the measurement of the value α LID_MAG  is considered reliable; and if the first reliability angle φ 1  is smaller than or equal to the threshold angle φ th , the measurement of the value LID_MAG is considered unreliable. For instance, the threshold angle φ th  is equal to approximately 20°. Alternatively, the measurement of the value α LID_MAG  is considered reliable only if both of the angles φ a , φ b  are greater than the threshold angle φ th . 
     According to an aspect of the present disclosure, the control unit  27 , with the possible support of the memory  28 , is configured for executing the operations illustrated in  FIG.  5    and described hereinafter.  FIG.  5    is a schematic illustration of functional blocks implemented, via software and in an iterative way, by the control unit  27  and memory  28 . 
     It is evident that the functional blocks of  FIG.  5    can be implemented in hardware in a way in itself evident to the person skilled in the art. 
     In particular, at each instant (or iteration) t (e.g., 0&lt;t&lt;N, with N&gt;1), the control unit  27  acquires the first signal B 1  and the second signal B 2  via the first magnetometer  20  and the second magnetometer  22 , respectively. The first signal B 1  represents (e.g., comprises) the components Gx 1 , Gy 1 , and Gz 1  (in particular, Gx 1 (t), Gy 1 (t), and Gz 1 (t)), and the second signal B 2  represents (e.g., comprises) the components Gx 2 , Gy 2 , and Gz 2  (in particular, Gx 2 (t), Gy 2 (t), and Gz 2 (t)). 
     A calibration block  49  receives at input the components Gx 1 (t), Gy 1 (t), Gz 1 (t), Gx 2 (t), Gy 2 (t), and Gz 2 (t), and returns at output a first calibration value J 1 , indicative of the possible presence of magnetic interference and magnetic distortion of the magnetometers  20 ,  22 . In general, the first calibration value J 1  is correlated to a calibration reliability of the magnetometers  20 ,  22 . The first calibration value J 1  may be a binary value in the case of single threshold (reliable/unreliable calibration, for example J 1 =1 and, respectively, J 1 =0), or else a value proportional to a degree of reliability of calibration detected. 
     The calibration block  49  is illustrated in detail in  FIG.  5 A , with reference to the case where the first calibration value J 1  assumes a binary value. 
     In a block  49   a , the first calibration value J 1  is initialised at 0 (unreliable calibration). In addition, in block  49   a  the control unit  27  acquires, via the magnetometers  20 ,  22 , calibration data D 1  (e.g., equal to the signals B 1 , B 2 , or else comprising a result of processing of the signals B 1 , B 2  acquired in a first calibration interval). Furthermore, at the first iteration (t=1) there is performed, as better described hereinafter, a calibration in order to generate calibration parameters P cal  correlated to the electromagnetic conditions to which the magnetometers  20 ,  22  are subjected. In particular, the calibration parameters P cal  include a soft iron matrix (SI) and a hard-iron vector (HI), and are calculated in a way in itself known. Moreover, both at the first iteration (t=1) and at the subsequent iterations (t&gt;1), calibrated data D 2  are generated on the basis of the calibration data D 1  and of the calibration parameters P cal . In detail, the calibrated data D 2  are the result of processing of the calibration data D 1  performed via the calibration parameters P cal . 
     In a block  49   b  that follows block  49   a , a condition regarding calibration of the magnetometers  20 ,  22  is evaluated. In particular, it is determined whether it is necessary or desired to carry out a calibration of the magnetometers  20 ,  22 . This calibration enables compensation of electromagnetic effects to which the magnetometers  20 ,  22  are subjected, due to factors such as variations in time of magnetization of components arranged in the proximity to the magnetometers themselves or the presence of ferromagnetic material. In detail, in block  49   b  the control unit  27  compares the calibrated data D 2  with an expected range (e.g., defined between approximately 0.25 gauss and approximately 0.75 gauss), correlated to an expected intensity of the Earth&#39;s magnetic field. If a Euclidean norm |D 2 | of the calibrated data D 2  satisfies, at the current iteration t, a first relation (e.g., it is comprised in said expected range and, for instance, is comprised between approximately 0.25 gauss and approximately 0.75 gauss, extremes included) the condition on the calibration of the magnetometers  20 ,  22  yields a negative result, and it is not necessary to carry out a new calibration; if the Euclidean norm |D 2 | of the calibrated data D 2  does not satisfy, at the current iteration t, said first relation (e.g., it is not comprised in the expected range, and for instance it is less than 0.25 gauss or greater than 0.75 gauss) the condition on the calibration of the magnetometers  20 ,  22  yields a positive result, and it is necessary to carry out the new calibration. 
     If it is necessary to carry out calibration of the magnetometers  20 ,  22  (output “YES” from block  49   b ), said calibration is carried out, according to known techniques (e.g., via sphere-fitting or ellipsoid-fitting algorithms), in a block  49   c , which follows block  49   b  in the case of output “YES”. In detail, the portable device  10  is rotated freely in three-dimensional space by the operator, and simultaneously the control unit  27  acquires the signals B 1 , B 2  during a second calibration interval, via the magnetometers  20 ,  22 . The signals B 1 , B 2  acquired during the second calibration interval are processed according to known techniques for generating new calibration parameters P cal , which replace the previous calibration parameters P cal . During the second calibration interval, the first calibration value J 1  is set at 0. 
     In a block  49   d  following block  49   c , the first calibration value J 1  is set at 1, to indicate that the calibration is reliable. 
     If it is not necessary to carry out calibration of the magnetometers  20 ,  22  (output “NO” from block  49   b ), a condition regarding magnetic interference (e.g., interference caused by electromagnetic sources set in the proximity of the portable device  10 ) is evaluated. In particular, in a block  49   e  following block  49   b  in the case of output “NO”, it is determined whether the magnetometers  20 ,  22  are subjected to magnetic interference. In particular, the calibrated data D 2  are evaluated in time to determine whether the magnetometers  20 ,  22  are subjected to magnetic interference. In greater detail, if the Euclidean norm |D 2 | of the calibrated data D 2  satisfies a second relation (e.g., it does not vary significantly in time), the check on the condition regarding magnetic interference yields a negative result, and magnetic interference is not present; if the Euclidean norm |D 2 | of the calibrated data D 2  does not satisfy the second relation (e.g., it varies significantly in time), the check on the condition regarding magnetic interference yields a positive result, and magnetic interference is present. For instance, the second relation is satisfied if the variance of the Euclidean norm |D 2 | of the calibrated data D 2  is less than a given threshold. 
     If no magnetic interference is present (output “NO” from block  49   e ), the procedure described of block  49   d  is again carried out, and then the first calibration value J 1  is set at 1 to indicate that the calibration is reliable. 
     If magnetic interference is present (output “YES” from block  49   e ), the first calibration value J 1  is set at 0 in a block  49   f  following block  49   e  in the case of output “YES”, to indicate that the calibration is unreliable. 
     At output from the calibration block  49 , there is therefore the first calibration value J 1 , which, if it is equal to 0, indicates that the calibration is unreliable (and therefore also the measurement of the value α LID_MAG  will not be reliable), whereas, if it is equal to 1, indicates that the calibration is reliable (and therefore the measurement of the value α LID_MAG  could be reliable, as described hereinafter). 
     With reference to  FIG.  5   , in a typical condition of use of the portable device  10 , the base portion  14  lies in a horizontal plane XY, resting on an ideally flat surface. Since the magnetometers  20 ,  22  are in a fixed position and the orientation of the respective sensing axes is known, it is possible to calculate, via the control unit  27 , the value α LID_MAG  (in particular, α LID_MAG (t)) of the lid angle α LID  (in particular, α LID (t)) as expressed by Eq. (1). In detail, a first calculation block  50  implements Eq. (1), receiving at input the components Gx 1 (t), Gy 1 (t), Gz 1 (t), Gx 2 (t), Gy 2 (t), and Gz 2 (t), and returning at output the value α LID_MAG (t) of the lid angle α LID (t). 
     A first reliability block  52  receives at input, from the first and second magnetometers  20 ,  22 , the components Gx 1 (t), Gy 1 (t), Gz 1 (t), Gx 2 (t), Gy 2 (t), and Gz 2 (t) and implements Eq. (2) for calculating the first reliability angle φ 1  (in particular, φ 1 (t)), as described previously. The first reliability angle φ 1 (t) is then compared, as discussed previously, with the threshold angle φ a  to establish the reliability of the calculation of the value α LID_MAG (t). The first reliability block  52  therefore generates at output a first reliability value K 1 , which may be a binary value in the case of single threshold (reliable/unreliable, for example K 1 =1 and, respectively, K 1 =0), or else a value proportional to a degree of reliability detected. In this latter case, it is possible to envisage a plurality of thresholds of comparison of the first reliability angle φ 1 (t), so that the first reliability value K 1  will vary according to a staircase function, associating a different first reliability value K 1  when each threshold provided is exceeded. The first reliability value K 1  will therefore vary between a minimum value and a maximum value the more the components Gx 1 (t) and Gx 2 (t) decrease and the components Gy 1 (t), Gy 2 (t), Gz 1 (t) and Gz 2 (t) increase; the minimum reliability value K 1  may be the zero value, whereas the maximum reliability value K 1  is chosen between 0 (excluded) and 1 according to the considerations that will be made in what follows with reference to block  56 . Moreover, the first reliability value K 1  is correlated to the first calibration value J 1 . In detail, if the first calibration value J 1  is equal to 0 (unreliable calibration), the first reliability value K 1  is set at 0 (measurement of the value α LID_MAG (t) unreliable); if the first calibration value J 1  is equal to 1 (reliable calibration), the first reliability value K 1  is determined on the basis of what has been described previously. Likewise, if the first calibration value J 1  assumes said proportional values, the first reliability value K 1  is determined on the basis of what has been described previously and moreover is weighted as a function of the first calibration value J 1  in a known way (e.g., K 1 =K 1 ·J 1 ). 
     A determination block  53  receives at input the first reliability value K 1  from the first reliability block  52  and the value α LID_MAG (t) from the first calculation block  50 , and determines the lid angle α LID (t). 
     According to one embodiment, where the first reliability value K 1  assumes a binary value, the lid angle α LID (t) is equal to the value α LID_MAG (t) if K 1 =1 (i.e., if the measurement of the value α LID_MAG (t) is reliable), and is independent of the value α LID_MAG (t) if K 1 =0 (i.e., if the measurement of the value α LID_MAG (t) is unreliable). For instance, if K 1 =0 the lid angle α LID (t) is not updated and therefore is equal to α LID_MAG  (t−1). In the case where at the first iteration (t=1) the measurement of the value α LID_MAG (t) is not reliable, the lid angle α LID (t) is set equal to a predefined value; for example, it is set equal to 0°. 
     According to a different embodiment, where the first reliability value K 1  assumes said proportional values, the lid angle α LID (t) is calculated, on the basis of the value α LID_MAG (t) and as a function of the first reliability value K 1 , via a dynamic lowpass filter or a complementary filter. For instance, the lid angle α LID (t) is calculated via the following expression:
 
α LID ( t )=(1− K   1 ′)·α LID ( t− 1)+ K   1 ′−α LID_MAG ( t )(rad)  (3)
 
where K 1 ′=n·K 1 , with n=1 according to one aspect of the present disclosure or else, according to a different aspect of the present disclosure, 0&lt;n=n max  (e.g., n max =0.1) in order to reduce the noise of the magnetometers  20 ,  22 . In the case where at the first iteration (t=1) the measurement of the value α LID_MAG (t) is not reliable, the lid angle α LID (t) is set equal to a predefined value; for example, it is set equal to 0°. In addition, at the first iteration (t=1), since the value α LID  (t−1) corresponding to the previous instant t−1 does not exist, α LID (t) is, for example set at a value equal to α LID_MAG (t), or else at a predefined value.
 
     Alternatively, calculation of the lid angle α LID  may take into account directly and explicitly the first calibration value J 1 . In this case, the first reliability value K 1  is not correlated to the first calibration value J 1  and, for example, Eq. (3) implemented in the determination block  53  is replaced by the following expression:
 
α LID ( t )=(1− J   1   ·K   1 )·α LID ( t− 1)+ J   1   ·K   1 ·α LID_MAG ( t )(rad)  (3bis)
 
       FIG.  6    shows the portable device  10  in a different embodiment, analogous to the one illustrated in  FIG.  2   . 
     In particular, with reference to the embodiment of  FIG.  6   , the lid portion  12  moreover accommodates (e.g., integrates within it) a first accelerometer  30 , configured for detecting and/or calculating values of acceleration of the lid portion  12  along respective sensing axes x 3 , y 3 , z 3 , parallel to the sensing axes x 1 , y 1 , z 1 , respectively, of the first magnetometer  20 ; and the base portion  14  moreover accommodates (e.g., integrates within it) a second accelerometer  32 , configured for detecting and/or calculating values of acceleration of the base portion  14  along respective sensing axes x 4 , y 4 , z 4 , parallel to the sensing axes x 2 , y 2 , z 2 , respectively, of the second magnetometer  22 . It is here pointed out that, in the embodiment here considered, the axis R of the hinge  15  is always parallel to the sensing axes x 1 , x 2 , x 3 , x 4  in any operative condition (lid portion  12  closed or open) and for any orientation of the device  10  in the triaxial reference system XYZ. The first and second accelerometers  30 ,  32  are operatively coupled to the control unit  27  and/or to the memory  28  and are configured to detect a movement and/or change of orientation of the portable device  10  by measuring accelerations. The first and second accelerometers  30 ,  32  are, for example, accelerometers obtained with MEMS technology. 
     In particular, as has been described with reference to  FIG.  3   , in the passage from the operative condition S1 to the operative condition S2 (or likewise from the operative condition S2 to the operative condition S3), the first accelerometer  30  detects a variation of the component of the acceleration of gravity g along the axes z 3  and y 3  and determines that the angle α LID  has increased (the reverse applies in the passage from the condition S2 to the condition S1, or from the condition S3 to the condition S2). 
     It is to be noted, in particular, that the acceleration of gravity g is given, in the operative condition S1, exclusively by the value detected along the axis z 3  and, in the operative condition S2, exclusively by the value detected along the axis y 3 . In an intermediate condition, for example when the angle α LID  is equal to 45°, both of the axes y 3  and z 3  yield the same value of acceleration. 
     In the operative condition S1, the sensing axis z 3  is parallel to the gravity acceleration vector g (the projection of the gravity acceleration vector g on the axis z 3  is maximum), in the operative condition S2, the sensing axis z 3  is orthogonal to the gravity acceleration vector g (the projection of the gravity acceleration vector g on the axis z 3  is minimum), and in the operative condition S3, the sensing axis z 3  is parallel to the gravity acceleration vector g, but has an opposite orientation as compared to the operative condition S1 (the projection of the gravity acceleration vector g on the axis z 3  is maximum, but with opposite sign). 
     In order to calculate a value of the angle α LID , it is possible to exploit the projection of the gravity acceleration vector g on the respective three sensing axes of the first and second accelerometers  30 ,  32 , taking into consideration the constraints due to the presence of the hinge  15 . In this case, a value α LID_ACC  of the angle α LID  can be calculated as: 
                     α     LID   ⁢           ⁢   _   ⁢           ⁢   ACC       =       arctan   ⁢           ⁢   2   ⁢     (           Az   4     ·     Ay   3       -       Ay   4     ·     Az   3               Az   4     ·     Az   3       +       Ay   4     ·     Ay   3           )       +     π   ⁡     (   rad   )                 (   4   )               
where arctan 2 is the known trigonometric function, Az 3  is the value of acceleration detected by the first accelerometer  30  along the sensing axis z 3 , Ay 3  is the value of acceleration detected by the first accelerometer  30  along the sensing axis y 3 , Az 4  is the value of acceleration detected by the second accelerometer  32  along the sensing axis z 4 , and Ay 4  is the value of acceleration detected by the second accelerometer  32  along the sensing axis y 4 . Eq. (4) shows how the value α LID_ACC  measured via the accelerometers  30 ,  32  represents a relative orientation (i.e., an orientation that is not absolute in space) between the lid portion  12  and the base portion  14 .
 
     When the portable device  10  is oriented with the axis R parallel to the axis Z, i.e., parallel to the gravity vector g (portable device  10  open like a book), passage into the operative conditions S1-S2-S3 does not cause a variation of the component of acceleration along the sensing axes z 3 , z 4 , y 3 , and y 4  of the first and second accelerometers  30 ,  32  since the component of the acceleration of gravity g along the axes indicated is always zero or substantially zero (the values Az 3 , Az 4 , Ay 3 , and Ay 4  of Eq. (4) are approximately equal to zero). 
     Situations of intermediate orientation, where the axis R forms an angle of less than 90°, but greater than 0°, with the axis Z, lead to measurements of the value α LID_ACC  that are all the more erroneous the more closely they approach the condition where the axis R is parallel to the axis Z. 
     What has been described previously may be applied, in a way in itself obvious, also to the operative condition where the portable device  10  is oriented with the axis R parallel to the axis Z, but rotated through 180° with respect to what has been discussed previously. 
     In particular, the reliability of the calculation of the value α LID_ACC  is therefore correlated to a second reliability angle φ 2 , which represents the measurement of the reliability angle φ made via the accelerometers  30 ,  32 . 
     According to one aspect of the present disclosure, a third angle φ c  is calculated via the first accelerometer  30  according to the following expression: 
                     φ   c     =       tan     -   1       ⁢           Ay   s   2     +     Az   s   2                Ax   s            ⁢     (   rad   )               (   5   )               
where Ax 3  is the value of acceleration detected by the first accelerometer  30  along the sensing axis x 3 . The third angle φ c  therefore varies between 0° and 90°. Likewise, a fourth angle φ d  is calculated via the second accelerometer  32 .
 
     The second reliability angle φ 2  is correlated to the third angle φ c  and/or to the fourth angle φ d , as has been described previously with reference to the first reliability angle (Pi. 
     If the second reliability angle φ 2  is greater than a further threshold angle (e.g., equal to the threshold angle φ th ), the measurement of the value α LID_ACC  is considered reliable, and if the second reliability angle φ 2  is smaller than or equal to said further threshold angle, the measurement of the value α LID_ACC  is considered unreliable. Alternatively, the measurement of the value α LID_ACC  is considered reliable only if both of the angles φ c , φ d  are greater than the further threshold angle. 
     In order to prevent the measurements of the angle α LID  from presenting an increasingly lower reliability the more closely they approach the condition of  FIG.  4 A  (axis R parallel to the magnetic field B), as described for the portable device  10  of  FIG.  2   , in the embodiment of  FIG.  6    the measurements obtained by the first and second accelerometers  30 ,  32  are fused with the measurements obtained by the first and second magnetometers  20 ,  22 ; for example, the measurements obtained from the first and second accelerometers  30 ,  32  are more weighted (and, accordingly, the measurements obtained from the first and second magnetometers  20 ,  22  are less weighted), the smaller the angle between the axis R and the magnetic field B (i.e., the more closely the condition of  FIG.  4 A  is approached). In this way, the reliability of the measurement of the angle α LID  is guaranteed both when the axis R is parallel to the magnetic field B and when it is parallel to the acceleration of gravity g (i.e., parallel to the axis Z). Since the magnetic field B and the acceleration of gravity g are mutually orthogonal, the measurement of the angle α LID , made as described more fully hereinafter, is always reliable. 
     According to one aspect of the present disclosure, the control unit  27 , with the optional support of the memory  28 , is moreover operatively connected to the accelerometers  30 ,  32  and is configured for executing the operations illustrated in  FIG.  7    and described hereinafter.  FIG.  7    is a schematic illustration of functional blocks analogous to the ones illustrated in  FIG.  5   . 
     In particular, moreover, a second calculation block  55  is represented in  FIG.  7    and configured for receiving at input the values of acceleration (comprising, in detail, the components Ay 3 , Az 3 , Ay 4  and Az 4 ) detected by the first and second accelerometers  30 ,  32 , and calculating the value α LID_ACC  of the lid angle α LID  on the basis of Eq. (4). 
     Optionally, a second reliability block  54  is moreover present, receiving at input, from the first and second accelerometers  30 ,  32 , the components Ax 3 (t), Ay 3 (t), Az 3 (t), Ax 4 (t), Ay 4 (t), and Az 4 (t), and implementing Eq. (5) for calculating the second reliability angle φ 2  (in particular, φ 2 (t)). As has been described previously with reference to the first reliability angle (pi, the second reliability angle φ 2 (t) is then compared with the further threshold angle to establish the reliability of the calculation of the value α LID_ACC (t). The second reliability block  54  therefore generates at output a second reliability value K 2  analogous to the first reliability value K 1 . 
     A first fusion block  56 , replacing in  FIG.  7    the determination block  53  of  FIG.  5   , has the function of generating a final value, deemed reliable, of the lid angle α LID  on the basis of the first reliability value K 1  and/or the second reliability value K 2 . The first fusion block  56  receives at input the first reliability value K 1  and/or the second reliability value K 2  and both of the values α LID_MAG , α LID_ACC  calculated, respectively, according to Eq. (1) (i.e., using just the signals of the magnetometers  20 ,  22 ) and according to Eq. (4) (i.e., using just the signals of the accelerometers  30 ,  32 ). 
     According to one embodiment, the first fusion block  56  implements a lowpass filter that enables filtering of the noise of the magnetometers  20 ,  22  and the linear accelerations of the accelerometers  30 ,  32 , said filter being defined by the following expression:
 
α LID ( t )= K   LP ·α LID_ACC_MAG ( t )+(1− K   LP )·α LID ( t− 1)(rad)  (6)
 
where K LP  is a coefficient comprised between 0 and 1 (e.g., it is equal to 0.1) and α LID_ACC_MAG (t) α LID_ACC_MAG (t) is a value thus defined:
         if K 1 =0 and K 2 ≠0 (i.e., magnetometers  20 ,  22  unreliable, and accelerometers  30 ,  32  reliable), then
 
α LID_ACC_MAG ( t )=α LID_ACC ( t )α LID_ACC_MAG ( t )
   if K 1 ≠0 and K 2 =0 (i.e., accelerometers  30 ,  32  unreliable, and magnetometers  20 ,  22  reliable), then
 
α LID_ACC_MAG ( t )=α LID_MAG ( t )α LID_ACC_MAG ( t )=α LID_MAG ( t )
   if K 1 ≠0 and K 2 ≠0 (i.e., accelerometers  30 ,  32  and magnetometers  20 ,  22  reliable), then       

                       α     LID   ⁢           ⁢   _   ⁢           ⁢   ACC   ⁢           ⁢   _   ⁢           ⁢   MAG       ⁡     (   t   )       =           K   1     ·       α     LID   ⁢           ⁢   _   ⁢           ⁢   MAG       ⁡     (   t   )         +       K   2     ·       α     LID   ⁢           ⁢   _   ⁢           ⁢   ACC       ⁡     (   t   )               K   1     +     K   2                                 
i.e., the value α LID_ACC_MAG (t) is a weighted average of the values α LID_MAG (t) and α LID_ACC (t), where the weights are the reliability parameters K 1 , K 2 .
 
     Furthermore, if K 1 =0 and K 2 =0 (i.e., accelerometers  30 ,  32 , and magnetometers  20 ,  22  unreliable), the coefficient K LP  is set at 0 in such a way that the estimate of the lid angle α LID (t) is not updated, and therefore α LID (t)=α LID (t−1). 
     Moreover, optionally a further calibration block, of a type in itself known, analogous to the calibration block  49  and not illustrated, receives at input the components Ax 3 (t), Ay 3 (t), Az 3 (t), Ax 4 (t), Ay 4 (t), and Az 4 (t), verifies whether said components are calibrated and returns at output calibrated components (said components at output being equal to the components at input if the components at input are calibrated, and being different from the components at input if the components at input are not calibrated). 
     According to a different embodiment, illustrated in  FIG.  8    and analogous to the one shown in  FIG.  2   , the lid portion  12  moreover accommodates (e.g., integrates within it) a first gyroscope  40 , configured for detecting and/or calculating an orientation and rotation of the lid portion  12  along, and about, sensing axes l 1 , m 1 , n 1  that are parallel, respectively, to the sensing axes x 1 , y 1 , z 1  of the first magnetometer  20 ; and the base portion  14  moreover accommodates (e.g., integrates within it) a second gyroscope  42 , configured for detecting and/or calculating an orientation and rotation of the base portion  14  along, and about, sensing axes l 2 , m 2 , n 2  that are parallel, respectively, to the sensing axes x 2 , y 2 , z 2  of the second magnetometer  22 . It is here pointed out that, in the embodiment here considered, the axis R of the hinge  15  is always parallel to the sensing axes x 1 , x 2 , l 1 , l 2  in any operative condition (lid portion  12  closed or open) and for any orientation of the device  10  in the triaxial reference system XYZ. The first and second gyroscopes  40 ,  42  are operatively coupled to the control unit  27  and/or to the memory  28  and are configured to detect a movement of the portable device  10  by measuring angular velocities. The first and second gyroscopes  40 ,  42  are, for example, gyroscopes obtained with MEMS technology. 
     In order to prevent the measurements of the angle α LID  from presenting an increasingly lower reliability, the closer they approach the condition of  FIG.  4 A  (axis R parallel to the magnetic field B), as described for the portable device  10  of  FIG.  2   , in the embodiment of  FIG.  8    the measurements obtained from the first and second gyroscopes  40 ,  42  are fused with the measurements obtained from the first and second magnetometers  20 ,  22 ; for example, the measurements obtained from the first and second gyroscopes  40 ,  42  are more weighted (and, accordingly, the measurements obtained from the first and second magnetometers  20 ,  22  are less weighted), the more the angle between the axis R and the magnetic field B decreases (i.e., the more closely the condition of  FIG.  4 A  is approached). In this way, the reliability of the measurement of the angle α LID  is guaranteed even when the axis R is parallel to the magnetic field B. 
     The fusion of the measurements of the magnetometers  20 ,  22  with those of the gyroscopes  40 ,  42  is not carried out occasionally: as better described hereinafter, according to one aspect of the present disclosure, a complementary filter is used (but it is also possible to use other types of filtering, e.g., Kalman filtering), and the magnetometric component is rejected or attenuated, the more the angle between the axis R and the magnetic field B decreases. The magnetometric component specifically has the function of correcting the drift of the angle calculated by the gyroscopes  40 ,  42 . 
     The gyroscopic contribution obtained by means of the measurements of the first and second gyroscopes  40 ,  42  acquired at the current instant t is given by
 
Δ α =(ω x2 −ω x1 )· dt (rad)  (7)
 
where ω x1  is the angular velocity measured by the first gyroscope  40  with respect to the sensing axis  11 , ω x2  is the angular velocity measured by the second gyroscope  42  with respect to the sensing axis l 2 . The value dt represents the time that has elapsed between the instant t−1 and the instant t (data-sampling or data-acquisition time of the gyroscopes  40 ,  42 , which in turn may depend upon the updating time of the system, for example comprised between 25 Hz and 200 Hz). For instance, if sampling of the output of the gyroscopes  40 ,  42  occurs at 100 Hz, the parameter dt is equal to 0.01 s.
 
     According to one aspect of the present disclosure, the control unit  27 , with the possible support of the memory  28 , is moreover operatively connected to the gyroscopes  40 ,  42  and is configured for executing the operations illustrated in  FIG.  9    and described hereinafter.  FIG.  9    is a schematic illustration of functional blocks analogous to the ones represented in  FIG.  5   . 
     In particular,  FIG.  9    further comprises a third calculation block  58  configured for receiving at input the values of angular velocity ω x1 , ω x2  detected by the first and second gyroscopes  40 ,  42 , and calculating a value α LID_GYR  of the lid angle α LID  on the basis of Eq. (8) referred to in what follows. 
     For this purpose, the third calculation block  58  includes a sub-block  58   a  configured for calculating (at the instant t) the variation Δ α  of the value α LID (t) of the lid angle α LID  with respect to the value α LID (t−1) previously measured (at the previous instant t−1), according to Eq. (7) provided above. 
     In addition, the third calculation block  58  includes a further sub-block  58   b , configured for receiving the variation value Δ α  and the last value α LID (t−1) of the lid angle α LID  calculated and deemed reliable (e.g., generated at output from a second fusion block  60 , described hereinafter), and updating in a recursive way said last value α LID (t−1) of the lid angle α LID  using the variation value Δ α . The sub-block  58   b  therefore implements the following expression:
 
α LID_GYR ( t )=Δ α +α LID ( t− 1)(rad)  (8)
 
The second fusion block  60  has the function of generating a final value, deemed reliable, of the lid angle α LID  on the basis of the first reliability value K 1  calculated by the first reliability block  52 . The second fusion block  60  receives at input both of the values α LID_MAG (t), α LID_GYR (t) calculated according to Eq. (1) (i.e., using just the signals of the magnetometers  20 ,  22 ) and, respectively, according to Eq. (8) (i.e., by updating the value α LID (t−1) with the variation Δ α  obtained via measurements supplied by the gyroscopes  40 ,  42 ).
 
     According to one embodiment, the second fusion block  60  implements a complementary filter between the values α LID_MAG (t) and α LID_GYR (t), according to the following expression:
 
α LID ( t )= K   1 ′·α LID_MAG ( t )+(1− K   1 ′)·((ω x2 −ω x1 )· dt+α   LID ( t− 1))
 
α LID ( t )= K   1 ′·α LID_MAG ( t )+(1− K   1 ′)·((ω x2 −ω x1 )· dt+α   LID ( t− 1))   (9)
 
where K 1 ′=n·K 1 , with n=1 according to one aspect of the present disclosure or else, according to a different aspect of the present disclosure, 0&lt;n≤n max  (e.g., n max =0.1) in order to reduce the noise of the magnetometers  20 ,  22 .
 
     In particular, since the value α LID  (t−1) does not exist at the first iteration (t=1), for example α LID (t) is set at a value equal to α LID_MAG (t) or else at a predefined value (e.g., 0°). 
     From an examination of the characteristics of the disclosure provided according to the present disclosure the advantages that it affords emerge clearly. 
     In particular, the operations of calculation of the lid angle α LID  between the lid portion  12  and the base portion  14  do not require the calculation of the absolute orientation of the lid portion  12  and of the base portion  14 , unlike the prior art where measurements are made of absolute orientation in space of respective functional blocks, with respect to which it is desired to calculate a lid angle. 
     In particular, the presence of the magnetometers  20 ,  22  enables reduction of the overall cost of the portable device  10 . In addition, the magnetometers  20 ,  22  are immune from effects due to linear accelerations and drift in time. The magnetometers  20 ,  22  guarantee a reliable measurement when the portable device  10  is open like a book (i.e., when the axis R is parallel to the acceleration of gravity g). 
     Furthermore, use of the first reliability value K 1 , associated, as has been said, to an evaluation of reliability of the measurements obtained via the magnetometers  20 ,  22 , makes the methodology of the present disclosure adaptive as a function of various operative conditions and of the service life of the magnetometers themselves. 
     Real-time calibration of the magnetometers  20 ,  22  prevents magnetic interference (block  49   e ) and magnetic distortion (block  49   b ) from affecting the measurement of the lid angle α LID . 
     With reference to the embodiment of  FIG.  6   , the simultaneous measurement made by the magnetometers  20 ,  22  and the accelerometers  30 ,  32  makes it possible, in addition to the advantages already listed with reference to  FIG.  2   , to guarantee, via the accelerometers  30 ,  32  a reliable measurement even in the case where the axis R is parallel to the magnetic field B, and in the case of magnetic anomalies. 
     With reference to the embodiment of  FIG.  8   , the simultaneous measurement made by the magnetometers  20 ,  22  and the gyroscopes  40 ,  42  makes it possible, in addition to the advantages already listed with reference to  FIG.  2   , to guarantee, via the gyroscopes  40 ,  42 , a reliable measurement even in the case where the axis R is parallel to the magnetic field B. The gyroscopes  40 ,  42  moreover determine an ample bandwidth of the measurement of the lid angle α LID . In addition, this embodiment enables reliable measurements both in the case where the portable device  10  is open like a book and, simultaneously, magnetic anomalies are present and in the case where the portable device  10  is open like a book and is simultaneously subjected to shaking (and therefore to linear accelerations). The recursive use of formulae, in a closed-loop system, moreover makes the system as a whole stable, rapid, and with a low computational load required. In fact, the gyroscopes  40 ,  42  are not sensitive to high-frequency disturbance, as occurs, instead, for the accelerometers, or to magnetic disturbance, as occurs, instead, for the magnetometers; at the same time, the drawbacks associated to the calculation of the lid angle α LID  performed only by means of gyroscopes (storage of error and lack of knowledge of the initial lid angle upon switching-on of the portable device  10 ) are solved thanks to the simultaneous measurement made by the magnetometers  20 ,  22 . 
     Finally, it is clear that modifications and variations may be made to the disclosure described and illustrated herein, without thereby departing from the scope thereof. 
     In general, in the context of the present disclosure, the lid angle α LID  is the angle between two elements (even separate from one another, i.e., not having the hinge  15 ) or parts that concur in forming an electronic device or system for display of information (electronic apparatus). Such elements or parts are for example: a keypad and a screen; a dual-screen device; a keypad and a tablet; a keypad and a smartphone; a smartphone and a tablet; two smartphones; two portions of display of a foldable smartphone; two tablets; or any other combination of keypad, tablet, smartphone, and screen. 
     Furthermore, it should be noted that the magnetometers  20 ,  22 , the accelerometers  30 ,  32 , and the gyroscopes  40 ,  42  may be implemented in: (i) modules separate from one another; (ii) 6-axes inertial-sensor modules (e.g., a first module integrating the first magnetometer  20  and the first accelerometer  30 , and a second module integrating the second magnetometer  22  and the second accelerometer  32 ); (iii) 9-axes inertial-sensor modules (a first module integrating the first magnetometer  20 , the first accelerometer  30 , and the first gyroscope  40 , and a second module integrating the second magnetometer  22 , the second accelerometer  32 , and the second gyroscope  42 ). In this latter case, it is also possible to make a 9-axes measurement for guaranteeing an accurate measurement of the lid angle α LID  in any condition of use and external factors of the portable device  10 . 
     In some embodiments, a method for controlling at least one function of an electronic apparatus ( 10 ) as a function of a value of a lid angle (αLID) between a first hardware element ( 12 ;  14 ) and a second hardware element ( 14 ;  12 ) of said electronic apparatus ( 10 ), wherein the first hardware element ( 12 ;  14 ) accommodates a first magnetometer ( 20 ;  22 ) and the second hardware element ( 14 ;  12 ) accommodates a second magnetometer ( 22 ;  20 ) and is orientable with respect to the first hardware element ( 12 ;  14 ), may be summarized as including the steps of: generating, by the first magnetometer ( 20 ) and by the second magnetometer ( 22 ), first signals (B1, B2) that are measurements of a magnetic field (B) external to the electronic apparatus ( 10 ) and are indicative of a relative orientation of the first hardware element with respect to the second hardware element; acquiring, by a processing unit ( 27 ,  28 ) of the electronic apparatus ( 10 ), said first signals (B1, B2); generating, by the processing unit ( 27 ,  28 ) and as a function of the first signals (B1, B2), a calibration parameter (J1) indicative of a condition of calibration of the first and second magnetometers ( 20 ,  22 ); generating, by the processing unit ( 27 ,  28 ) and as a function of the first signals (B1, B2), a reliability value (K1) indicative of a condition of reliability of the first signals (B1, B2); calculating ( 50 ), by the processing unit ( 27 ,  28 ), a first intermediate value (αLID_MAG) of said lid angle (αLID) on the basis of the first signals (B1, B2); calculating ( 53 ), by the processing unit ( 27 ,  28 ), a current value of said lid angle (αLID) on the basis of the calibration parameter (J1), of the reliability value (K1), and of said first intermediate value (αLID_MAG) of the lid angle (αLID); and controlling said function of the electronic apparatus ( 10 ) as a function of the current value of the lid angle (αLID). 
     In some embodiments, the first and second hardware elements ( 12 ,  14 ) are rotatable with respect to one another about a rotation axis (R), the first and second hardware elements ( 12 ,  14 ) have a respective first surface ( 12   a ) and a respective second surface ( 14   a ) directly faceable one another and defining between them the lid angle (αLID), and the first magnetometer ( 20 ) is a triaxial magnetometer having a respective first sensing axis (x1), a respective second sensing axis (y1), and a respective third sensing axis (z1), and the second magnetometer ( 22 ) is a triaxial magnetometer having a respective first sensing axis (x2), a respective second sensing axis (y2), and a respective third sensing axis (z2), the first sensing axes (x1, x2) being parallel to the rotation axis (R). 
     In some embodiments, the step of calculating the first intermediate value (αLID_MAG) includes executing the operation: 
     
       
         
           
             
               arctan 
               ⁢ 
               
                   
               
               ⁢ 
               2 
               ⁢ 
               
                 ( 
                 
                   
                     
                       G 
                       ⁢ 
                       
                         
                           z 
                           2 
                         
                         · 
                         
                           Gy 
                           1 
                         
                       
                     
                     - 
                     
                       
                         Gy 
                         2 
                       
                       · 
                       
                         Gz 
                         1 
                       
                     
                   
                   
                     
                       G 
                       ⁢ 
                       
                         
                           z 
                           2 
                         
                         · 
                         
                           Gz 
                           1 
                         
                       
                     
                     + 
                     
                       G 
                       ⁢ 
                       
                         
                           y 
                           2 
                         
                         · 
                         
                           Gy 
                           1 
                         
                       
                     
                   
                 
                 ) 
               
             
             + 
             π 
           
         
       
     
     where Gy 1  is a component of the first signal (B 1 ) detected by the first magnetometer ( 20 ) along the respective second sensing axis (y 1 ), Gz 1  is a component of the first signal (B 1 ) detected by the first magnetometer ( 20 ) along the respective third sensing axis (z 1 ), Gy 2  is a component of the second signal (B 2 ) detected by the second magnetometer ( 22 ) along the respective second sensing axis (y 2 ), and Gz 2  is a component of the second signal (B 2 ) detected by the second magnetometer ( 22 ) along the respective third sensing axis (z 2 ). 
     In some embodiments, the step of generating the reliability value (K 1 ) includes: calculating a reliability angle (φ 1 ; φ a , φ b ) on the basis of the first signals (B 1 , B 2 ); and generating the reliability value (K 1 ) on the basis of a comparison between the reliability angle (φ 1 ; φ a , φ b ) and a threshold angle. 
     In some embodiments, the reliability angle (φ 1 ) is measured between the rotation axis (R) and the magnetic field (B) external to the electronic apparatus ( 10 ), and wherein the step of calculating the reliability angle (φ 1 ) includes: calculating a first (φ a ) intermediate angle on the basis of the first signal (B 1 ) of the first magnetometer ( 20 ) by executing the operation: 
     
       
         
           
             
               tan 
               
                 - 
                 1 
               
             
             ⁢ 
             
               
                 
                   
                     G 
                     ⁢ 
                     
                       y 
                       1 
                       2 
                     
                   
                   + 
                   
                     G 
                     ⁢ 
                     
                       z 
                       1 
                       2 
                     
                   
                 
               
               
                  
                 
                   Gx 
                   1 
                 
                  
               
             
           
         
       
     
     and/or calculating a second (φ b ) intermediate angle on the basis of the first signal (B 2 ) of the second magnetometer ( 22 ) by executing the operation: 
     
       
         
           
             
               tan 
               
                 - 
                 1 
               
             
             ⁢ 
             
               
                 
                   
                     G 
                     ⁢ 
                     
                       y 
                       2 
                       2 
                     
                   
                   + 
                   
                     G 
                     ⁢ 
                     
                       z 
                       2 
                       2 
                     
                   
                 
               
               
                  
                 
                   Gx 
                   2 
                 
                  
               
             
           
         
       
     
     where Gx 1  is a component of the first signal (B 1 ) detected by the first magnetometer ( 20 ) along the respective first sensing axis (x 1 ), and Gx 2  is a component of the second signal (B 2 ) detected by the second magnetometer ( 22 ) along the respective first sensing axis (x 2 ); and generating the reliability angle (φ 1 ) on the basis of the first intermediate angle (φ a ) and/or of the second intermediate angle (φ b ), wherein: the reliability angle (φ 1 ) is equal to the first angle (φ a ); or the reliability angle (φ 1 ) is equal to the second angle (φ b ); or the reliability angle (φ 1 ) is equal to an average of the of the first and second angles (φ a , φ b ); or the reliability angle (φ 1 ) is equal to a weighted average of the first and second angles (φ a , φ b ). 
     In some embodiments, the step of generating the reliability value (K 1 ) includes: 
     calculating a first reliability angle (φ a ) on the basis of the first signals (B 1 , B 2 ) by executing the operation: 
     
       
         
           
             
               tan 
               
                 - 
                 1 
               
             
             ⁢ 
             
               
                 
                   
                     G 
                     ⁢ 
                     
                       y 
                       1 
                       2 
                     
                   
                   + 
                   
                     G 
                     ⁢ 
                     
                       z 
                       1 
                       2 
                     
                   
                 
               
               
                  
                 
                   Gx 
                   1 
                 
                  
               
             
           
         
       
     
     where Gx 1  is a component of the first signal (B 1 ) detected by the first magnetometer ( 20 ) along the respective first sensing axis (x 1 ); calculating a second reliability angle (φ b ) on the basis of the first signals (B 1 , B 2 ) by executing the operation: 
     
       
         
           
             
               tan 
               
                 - 
                 1 
               
             
             ⁢ 
             
               
                 
                   
                     G 
                     ⁢ 
                     
                       y 
                       2 
                       2 
                     
                   
                   + 
                   
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                     ⁢ 
                     
                       z 
                       2 
                       2 
                     
                   
                 
               
               
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                   Gx 
                   2 
                 
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     where Gx 2  is a component of the second signal (B 2 ) detected by the second magnetometer ( 22 ) along the respective first sensing axis (x 2 ); and generating the reliability value (K 1 ) on the basis of a first comparison between the first reliability angle (φ a ) and a threshold angle and on the basis of a second comparison between the second reliability angle (φ b ) and said threshold angle. 
     In some embodiments, the step of generating the calibration parameter (J 1 ) includes: generating ( 49   a ) calibrated data (D 2 ) on the basis of the first signals (B 1 , B 2 ) through calibration parameters (P cal ); comparing the calibrated data (D 2 ) with respective comparison data, generating a result of said comparison that indicates a need or otherwise to calibrate the first and second magnetometers ( 20 ,  22 ); and if the result of said comparison indicates the need to calibrate the first and second magnetometers, executing the steps of: calibrating ( 49   c ) the first and second magnetometers ( 20 ,  22 ) to generate new calibration parameters (P cal ), assigning ( 49   d ) to the calibration parameter (J 1 ) a first value indicating execution of the calibration of the first and second magnetometers ( 20 ,  22 ), and replacing ( 49   c ) said calibration parameters (P cal ) with the new calibration parameters (P cal ) generated by calibrating the first and second magnetometers ( 20 ,  22 ). 
     In some embodiments, the step of generating ( 49 ) the calibration parameter (J 1 ) further includes: if the result of said comparison does not indicate the need to calibrate the first and second magnetometers, executing the steps of: determining ( 49   e ), on the basis of the calibrated data (D 2 ), whether a condition of magnetic interference has been verified at the first and second magnetometers ( 20 ,  22 ); and in the absence of said magnetic interference, assigning ( 49   d ) to the calibration parameter (J 1 ) said first value; or in the presence of said magnetic interference, assigning ( 49   f ) to the calibration parameter (J 1 ) a second value different from the first value. 
     In some embodiments, the reliability value (K 1 ) is a function of the calibration parameter (J 1 ), wherein the step of calculating ( 53 ) the current value of said lid angle (α LID ) comprises recursively updating said current value of the lid angle (α LID ) by executing the operation:
 
α LID ( t )=(1− K   1 ′)·α LID ( t− 1)+ K   1 ′·α LID_MAG ( t )
 
     with K 1 ′=n·K 1 , where K 1  is the reliability value and has a value equal to or greater than 0 and smaller than or equal to 1, n is a coefficient with a value greater than 0 and smaller than or equal to 1, α LID (t) is the current value of the lid angle (α LID ), α LID (t−1) is a value of the lid angle (α LID ) at an instant immediately preceding the instant of the current value α LID (t), and α LID_MAG (t) is the first intermediate value. 
     In some embodiments, the first hardware element ( 12 ;  14 ) further accommodates a first accelerometer ( 30 ;  32 ), and the second hardware element ( 14 ;  12 ) further accommodates a second accelerometer ( 32 ;  30 ), the control method further comprising the steps of: acquiring, by the processing unit ( 27 ,  28 ) through the first and second accelerometers ( 30 ,  32 ), second signals indicative of measurements of relative orientation of the first and second hardware elements; calculating ( 55 ), by the processing unit ( 27 ,  28 ), a second intermediate value (α LID_ACC ) of said lid angle (α LID ) on the basis of the second signals; and calculating ( 56 ), by the processing unit ( 27 ,  28 ), said current value of the lid angle (α LID ) further on the basis of said second intermediate value (α LID_ACC ) of the lid angle (α LID ). 
     In some embodiments, the method further includes the step of generating ( 54 ), by the processing unit ( 27 ,  28 ) and as a function of the second signals, a further reliability value (K 2 ) indicative of a condition of reliability of the second signals. 
     In some embodiments, the step of calculating ( 56 ) the current value of the lid angle (α LID ) includes executing the operation:
 
 K   LP ·α LID_ACC_MAG ( t )+(1− K   LP )·α LID ( t− 1)
 
     where α LID (t−1) is a value of the angle at an instant immediately preceding the instant of the current value, K LP  is a coefficient greater than or equal to 0 and smaller than or equal to 1, and α LID_ACC_MAG (t) is a value equal to: the second intermediate value (α LID_ACC ), if the reliability value (K 1 ) is equal to 0 and the further reliability value (K 2 ) is other than 0; or the first intermediate value (α LID_MAG ), if the reliability value (K 1 ) is other than 0 and the further reliability value (K 2 ) is equal to 0; or (K 1 ·α LID_MAG (t)+K 2 ·α LID_ACC (t))/(K 1 +K 2 ), if the reliability value (K 1 ) is other than 0 and the further reliability value (K 2 ) is other than 0, where α LID_MAG (t) is the first intermediate value, and α LID_ACC (t) is the second intermediate value, K 1  is the reliability value and K 2  is the further reliability value, and where K LP  is equal to 0 if the reliability value (K 1 ) is equal to 0 and the further reliability value (K 2 ) is equal to 0. 
     In some embodiments, the first hardware element ( 12 ;  14 ) further accommodates a first gyroscope ( 40 ;  42 ) and the second hardware element ( 14 ;  12 ) further accommodates a second gyroscope ( 42 ;  40 ), the method further comprising the steps of: acquiring, by the processing unit ( 27 ,  28 ) and through the first and second gyroscopes ( 40 ,  42 ), second signals indicative of measurements of relative orientation of the first and second hardware elements; calculating ( 58 ), by the processing unit ( 27 ,  28 ), a second intermediate value (α LID_GYR ) of said lid angle (α LID ) on the basis of the second signals; and calculating ( 60 ), by the processing unit ( 27 ,  28 ), said current value of the lid angle (α LID ) further on the basis of said second intermediate value (α LID_GYR ) of the lid angle (α LID ). 
     In some embodiments, the step of calculating the current value of the lid angle (α LID ) includes the step of executing a weighted sum of the first intermediate value (α LID_MAG ) and of the second intermediate value (α LID_GYR ). 
     In some embodiments, the step of executing the weighted sum includes executing the operation:
 
α LID ( t )= K   1 ′·α LID_MAG ( t )+(1− K   1 ′)·α LID_GYR ( t )
 
     with K 1 ′=n·K 1 , where K 1  is the reliability value and has a value equal to or greater than 0 and smaller than or equal to 1, n is a coefficient with a value greater than 0 and smaller than or equal to 1, α LID (t) is the current value of the angle, α LID_MAG (t) is the first intermediate value, and α LID_GYR (t) is the second intermediate value. 
     In some embodiments, an electronic apparatus ( 10 ) may be summarized as including: a first hardware element ( 12 ;  14 ) accommodating a first magnetometer ( 20 ;  22 ); and a second hardware element ( 14 ;  12 ) accommodating a second magnetometer ( 22 ;  20 ), orientable with respect to the first hardware element ( 12 ), and defining a lid angle (α LID ) with said first hardware element ( 12 ;  14 ). The first and second magnetometers ( 20 ,  22 ) are configured for generating first signals (B 1 , B 2 ) that are measurements of a magnetic field (B) external to the electronic apparatus ( 10 ) and are indicative of a relative orientation of the first hardware element with respect to the second hardware element. The electronic apparatus ( 10 ) further includes a processing unit ( 27 ,  28 ) configured for executing the operations of: acquiring said first signals (B 1 , B 2 ); generating, as a function of the first signals (B 1 , B 2 ), a calibration parameter (J 1 ) indicative of a condition of calibration of the first and second magnetometers ( 20 ,  22 ); generating, as a function of the first signals (B 1 , B 2 ), a reliability value (K 1 ) indicative of a condition of reliability of the first signals (B 1 , B 2 ); calculating ( 50 ) a first intermediate value (α LID_MAG ) of said lid angle (α LID ) on the basis of the first signals (B 1 , B 2 ); calculating ( 53 ) a current value of said lid angle (α LID ) on the basis of the calibration parameter (J 1 ), of the reliability value (K 1 ), and of said first intermediate value (α LID_MAG ) of the lid angle (α LID ); and controlling said function of the electronic apparatus ( 10 ) as a function of the current value of the lid angle (α LID ). 
     In some embodiments, the first magnetometer ( 20 ) is a triaxial magnetometer having a respective first sensing axis (x 1 ), a respective second sensing axis (y 1 ), and a respective third sensing axis (z 1 ) sensing axis, and the second magnetometer ( 22 ) is a triaxial magnetometer having a respective first sensing axis (x 2 ), a respective second sensing axis (y 2 ), and a respective third sensing axis (z 2 ), the first sensing axes (x 1 , x 2 ) being parallel to one another, and when said magnetic field (B) acts in a direction parallel to a rotation axis (R) about which the first and second hardware elements ( 12 ,  14 ) are rotatable with respect to one another, only the first sensing axes (x 1 , x 2 ) are subject to the magnetic field (B), and the processing unit ( 27 ,  28 ) is configured for assigning to the reliability value (K 1 ) a predefined value indicative of unreliability of the first signals (B 1 , B 2 ). 
     In some embodiments, the first hardware element ( 12 ;  14 ) further accommodates a first accelerometer ( 30 ;  32 ), the second hardware element ( 14 ;  12 ) further accommodates a second accelerometer ( 32 ;  30 ), and the processing unit ( 27 ,  28 ) is further configured for executing the operations of: acquiring, through the first and second accelerometers ( 30 ,  32 ), second signals indicative of measurements of relative orientation of the first and second hardware elements; calculating ( 55 ) a second intermediate value (α LID_ACC ) of said lid angle (α LID ) on the basis of the second signals; and calculating ( 56 ) said current value of the lid angle (α LID ) further on the basis of said second intermediate value (α LID_ACC ) of the lid angle (α LID ). 
     In some embodiments, the first hardware element ( 12 ;  14 ) further accommodates a first gyroscope ( 40 ;  42 ), and the second hardware element ( 14 ;  12 ) further accommodates a second gyroscope ( 42 ;  40 ); and the processing unit ( 27 ,  28 ) is further configured for executing the operations of: acquiring, through the first and second gyroscopes ( 40 ,  42 ), second signals indicative of measurements of relative orientation of the first and second hardware elements; calculating ( 58 ) a second intermediate value (α LID_GYR ) of said lid angle (α LID ) on the basis of the second signals; and calculating ( 60 ) said current value of the lid angle (α LID ) on the basis of said second intermediate value (α LID_GYR ) of the lid angle (α LID ). 
     In some embodiments, the first hardware element ( 12 ) is provided with a first user-interaction device ( 18 ) and the second hardware element ( 14 ) is provided with a second user-interaction device ( 16 ), and the operation of controlling said function of the electronic apparatus ( 10 ) comprises adapting operative features or operation features of the first interaction device ( 18 ) and/or of the second interaction device ( 16 ) as a function of the current value of the lid angle (α LID ). 
     In some embodiments, a software product is provided in which the software product is to be loaded into a processing unit ( 27 ,  28 ) of an electronic apparatus ( 10 ) comprising a first hardware element ( 12 ;  14 ) accommodating a first magnetometer ( 20 ;  22 ), and a second hardware element ( 14 ;  12 ) accommodating a second magnetometer ( 22 ;  20 ), orientable with respect to the first hardware element ( 12 ), and defining a lid angle (α LID ) with said first hardware element ( 12 ;  14 ); wherein the first and second magnetometers ( 20 ,  22 ) are configured for generating first signals (B 1 , B 2 ) that are measurements of a magnetic field (B) external to the electronic apparatus ( 10 ) and are indicative of a relative orientation of the first hardware element with respect to the second hardware element, said software product being designed in such a way that, when it is run, the processing unit ( 27 ,  28 ) becomes configured for: acquiring said first signals (B 1 , B 2 ); generating, as a function of the first signals (B 1 , B 2 ), a calibration parameter (J 1 ) indicative of a condition of calibration of the first and second magnetometers ( 20 ,  22 ); generating, as a function of the first signals (B 1 , B 2 ), a reliability value (K 1 ) indicative of a condition of reliability of the first signals (B 1 , B 2 ); calculating ( 50 ) a first intermediate value (α LID_MAG ) of said lid angle (α LID ) on the basis of the first signals (B 1 , B 2 ); calculating ( 53 ) a current value of said lid angle (α LID ) on the basis of the calibration parameter (J 1 ), of the reliability value (K 1 ), and of said first intermediate value (α LID_MAG ) of the lid angle (α LID ); and controlling said function of the electronic apparatus ( 10 ) as a function of the current value of the lid angle (α LID ). 
     The various embodiments described above can be combined to provide further embodiments. All of the U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and/or listed in the Application Data Sheet are incorporated herein by reference, in their entirety. 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.