Abstract: A method for detecting movements of a plurality of points (P) of a surface (21), comprising a measuring step during which an incident ultrasonic wave is emitted into the air towards the surface and an ultrasonic wave reflected into the air by the surface (21) is detected. During the measuring step, each measuring point is illuminated by the incident ultrasonic wave at a multiplicity of angles of incidence, and the reflected ultrasonic wave is detected by a network of receiving transducers (3) comprising a plurality of ultrasonic receiving transducers (3a). The movements of the surface are determined at a measuring point by determining a delay and/or a phase shift between two beam-forming signals for said measuring point.

Abstract: A method for detecting movements of a plurality of points (P) of a surface (21), comprising a measuring step during which an incident ultrasonic wave is emitted into the air towards the surface and an ultrasonic wave reflected into the air by the surface (21) is detected. During the measuring step, each measuring point is illuminated by the incident ultrasonic wave at a multiplicity of angles of incidence, and the reflected ultrasonic wave is detected by a network of receiving transducers (3) comprising a plurality of ultrasonic receiving transducers (3a). The movements of the surface are determined at a measuring point by determining a delay and/or a phase shift between two beam-forming signals for said measuring point.

Abstract: The present invention relates to a method for determining an acoustic response attributed to a location of an impact, in particular a touch event, on a surface of an object including at least one transducer comprising the steps of: a) receiving an acoustic signal from at least one transducer, wherein the signal corresponds to a predetermined excitation (E) at at least one location on the surface; b) determining an acoustic response based on the acoustic signal received in step a); and c) determining the acoustic response attributed to at least one location on the surface different to the location of the predetermined excitation based on at least two different acoustic responses determined in step b).

Abstract: The present invention relates to a method for determining an acoustic response attributed to a location of an impact, in particular a touch event, on a surface of an object including at least one transducer comprising the steps of: a) receiving an acoustic signal from at least one transducer, wherein the signal corresponds to a predetermined excitation (E) at at least one location on the surface; b) determining an acoustic response based on the acoustic signal received in step a); and c) determining the acoustic response attributed to at least one location on the surface different to the location of the predetermined excitation based on at least two different acoustic responses determined in step b).

Abstract: A method for determining the location of an impact on a surface (1) comprising N acoustic sensors (2a, 2b, 2c), transmitting a sensed signal si(t) to a processing unit (4) comprises the following steps (a) computing P intercorrelation products (b) calculating P inverse Fourier transforms p?ij (u) (c) computing for each area k, Pk(u)=?P?ij (u??ijk); d) finding k0, where a characterizing value of Pk0 (u) is greater than a given threshold value.

Abstract: A method for determining the position of impacts on an object comprising two acoustic sensors, and N active areas of said object, comprises the steps of: (a) receiving two acoustic signals S1(t) and S2(t); (b) calculating a sample signature function SIGS(?)=S1(?)?S2(?)*, where S1(?) and S2(?) are the respective Fourier transforms of S1(t) and S2(t), (c) comparing SIGS(?) with N predetermined reference signature functions SIGR,(?) corresponding to the predetermined area j for j from 1 to N; (d) determining the active area in which the impact occurred, on the basis of the comparison of step (c).

Abstract: For locating a touch on a tactile surface belonging to an object, mechanical waves are made to propagate in the object and these mechanical waves are picked up. Certain characteristics of the signal picked up are compared to a library of reference characteristics, and the position of the touch is deduced from this comparison.

Abstract: A method for determining the locations of at least two impacts F1 and F2 on a surface using one or more sensors Si, i=1 to n, with n being the number of sensors, and the impacts F1 and F2 generating a signal being sensed by the one or more sensors, wherein each sensor provides a sensed signal si(t), i=1 to n, with n being the number of sensors. To be able to determine simultaneous impacts of different amplitudes the method includes identifying the location x of one impact, and determining a modified sensed signal si?(t) for each sensor in which the contribution due to the identified impact is reduced and which is based on a comparison, in particular a correlation, of each of the sensed signals si(t) and a predetermined reference signal rij(t) corresponding to a reference impact Rj at location j. The method can also be based on couples of sensed signals.

Abstract: An automatic gain control circuit including a variable gain amplifier (11) adapted to receive a received signal (R) and to output an amplified signal (A) to an analog to digital converter (20), and a gain controller (12) which is connected to said variable gain amplifier (11) for receiving said amplified signal (A) and for controlling a gain of said variable gain amplifier (11). The gain controller (12) is adapted to determine an occurrence of a threshold event each time the amplified signal (A) has reached a predetermined threshold, decrease the gain of the variable gain amplifier (11) at each occurrence of a threshold event, measure a delay since the last threshold event, increase the gain of the variable gain amplifier (11) if the delay is greater than a delay specified value and if the gain of the variable gain amplifier (11) is not maximum.

Abstract: The invention relates to a method for determining a physical parameter representative of a point P of a plate by means of a device comprising a first receiver for measuring a wave propagating in the plate, and a calculation unit. The method includes the following steps: measuring, by means of the first receiver, a first signal s1(t) representative of a wave propagating in the plate; defining a closed contour C on the plate surrounding said point P, the contour C being the location on the plate on which either a wave is generated by a first emitter, or the first signal s1(t) is measured; and determining the physical parameter at point P on the plate by identifying, thanks to at least said first signal, a shape function fshape(f), in the following equation: formula (I), where Wcontour and Gplate are functions of Green, and the shape function fshape(f) is dependent on the frequency f of the wave and on the physical parameter.

Abstract: An access control installation adapted for controlling access from a first zone to a second zone, said installation comprising: at least one separating panel separating the first and second zones, said separating panel having at least one moving closure element (1) adapted for selectively opening or closing an opening; at least one opening actuator (3a, 3b) adapted for causing the closure element (1) selectively to prevent or to allow access via the opening; and a control circuit (5) for controlling the opening actuator. Said installation further comprises at least one sound sensor (6) fastened to the separating panel on the same side as the second zone and adapted for detecting knocks on the first surface of said separating panel, and the control circuit (5) is adapted for: recognizing a predetermined code represented by a particular sequence of knocks on the first surface; and controlling the opening actuator as a function of the recognized code.

Abstract: A method for determining the position of impacts on an object comprising two acoustic sensors, and N active areas of said object, comprises the steps of: (a) receiving two acoustic signals S1(t) and S2(t); (b) calculating a sample signature function SIGS(?)=S1(?)?S2(?)*, where S1(?) and S2(?) are the respective Fourier transforms of S1(t) and S2(t), (c) comparing SIGS(?) with N predetermined reference signature functions SIGR,(?) corresponding to the predetermined area j for j from 1 to N; (d) determining the active area in which the impact occurred, on the basis of the comparison of step (c).

Abstract: For locating a touch on a tactile surface belonging to an object (7), mechanical waves are made to propagate in the object and these mechanical waves are picked up.

Abstract: An automatic gain control circuit including a variable gain amplifier (11) adapted to receive a received signal (R) and to output an amplified signal (A) to an analog to digital converter (20), and a gain controller (12) which is connected to said variable gain amplifier (11) for receiving said amplified signal (A) and for controlling a gain of said variable gain amplifier (11). The gain controller (12) is adapted to determine an occurrence of a threshold event each time the amplified signal (A) has reached a predetermined threshold, decrease the gain of the variable gain amplifier (11) at each occurrence of a threshold event, measure a delay since the last threshold event, increase the gain of the variable gain amplifier (11) if the delay is greater than a delay specified value and if the gain of the variable gain amplifier (11) is not maximum.

Abstract: Method for locating an impact on a surface (9), in which acoustic sensors (6) pick up acoustic signals ski (t) generated by the impact and the impact is located by calculating, for a number of reference points of index j, a validation parameter representative of a function: PRODkji1i2. . . i2P(?)=?Ski1(?) ?Rji1(?)*?Ski2(?)*?Rji2(?) . . . ?Ski2p(?)*?Rji2p(?) where: ?Ski(?) and ?Rji(?)* are complex phases of Ski(?) and of Rji(?), for i=i1, i2, . . . , i2p, indices denoting sensors, Ski(?) and Rji(?) being the Fourier transform of ski(t) and rji(t), rji(t) being a reference signal corresponding to the sensor i for an impact at the reference point j, p being a non-zero integer no greater than NSENS/2.

Abstract: An access control installation adapted for controlling access from a first zone to a second zone, said installation comprising: at least one separating panel separating the first and second zones, said separating panel having at least one moving closure element (1) adapted for selectively opening or closing an opening; at least one opening actuator (3a, 3b) adapted for causing the closure element (1) selectively to prevent or to allow access via the opening; and a control circuit (5) for controlling the opening actuator. Said installation further comprises at least one sound sensor (6) fastened to the separating panel on the same side as the second zone and adapted for detecting knocks on the first surface of said separating panel, and the control circuit (5) is adapted for: recognizing a predetermined code represented by a particular sequence of knocks on the first surface; and controlling the opening actuator as a function of the recognized code.

Abstract: A man-machine interface method comprising generating physical interactions with active zones (10) belonging to an interface object (5), the active zones being associated with predetermined items of information, detecting the active zones where interactions occur by measuring at least one physical magnitude, and associating each detected interaction with the corresponding predetermined item of information. The active zones are defined for a predetermined finite length of time and they are then deactivated at the end of said predetermined length of time, and when interactions with the interface object are detected while the active zones are deactivated, the active zones are automatically redefined as a function of the first detected interactions.

Abstract: A method for determining the locations of at least two impacts F1 and F2 on a surface using one or more sensors Si, i=1 to n, with n being the number of sensors, and the impacts F1 and F2 generating a signal being sensed by the one or more sensors, wherein each sensor provides a sensed signal si(t), i=1 to n, with n being the number of sensors. To be able to determine simultaneous impacts of different amplitudes the method includes identifying the location x of one impact, and determining a modified sensed signal si?(t) for each sensor in which the contribution due to the identified impact is reduced and which is based on a comparison, in particular a correlation, of each of the sensed signals si(t) and a predetermined reference signal rij(t) corresponding to a reference impact Rj at location j. The method can also be based on couples of sensed signals.

Abstract: A method for determining the location of an impact on a surface (1) comprising N acoustic sensors (2a, 2b, 2c), transmitting a sensed signal si(t) to a processing unit (4) comprises the following steps (a) computing P intercorrelation products (b) calculating P inverse Fourier transforms p?ij (u) (c) computing for each area k, Pk(u)=?P?ij (u??ijk); d) finding k0, where a characterizing value of Pk0 (u) is greater than a given threshold value.

Abstract: Method for locating an impact on a surface (9), in which acoustic sensors (6) pick up acoustic signals ski (t) generated by the impact and the impact is located by calculating, for a number of reference points of index j, a validation parameter representative of a function: PRODkji1i2. . . i2p (?)=øSki1 (?) ØRji1(?)*øSki2 (?)*øRji2 (?) . . . ØSki2p (?)*ØRji2p (?) where: ØSki (?) and ØRji (?)* are complex phases of Ski (?) and of Rji (?), for i=i1, i2, . . . , i2p, indices denoting sensors, Ski(?) and Rji(?) being the Fourier transform of ski (t) and rji (t), rji (t) being a reference signal corresponding to the sensor i for an impact at the reference point j, p being a non-zero integer no greater than NSENS/2.