Gesture-detecting method for controlling an opening panel of a motor vehicle

Abstract

The invention relates to a gesture-detecting method for controlling an opening panel of a motor vehicle of reference frame Rv, comprising the following steps: emitting (EA) a radio-frequency signal intended to propagate to a target; receiving (EB) a radio-frequency signal called the return signal, from said target (5); calculating (EC) an angular amplitude of the moving target in an analysis plane of the reference frame Rv; comparing (ED) said angular amplitude with a threshold angle, in order to determine whether or not a movement of the target is deliberate, on the basis of the return signal; implementing gesture recognition (RG) with a view to detecting when the target is making a predetermined gesture; if the predetermined gesture is detected, and if the gesture is determined to be deliberate, generating (EE) a signal intended to control opening and / or unlocking of the opening panel.

Description

Gesture detection method for controlling an opening of a motor vehicle Description

[0001] The present disclosure relates to a gesture detection method intended for controlling an opening of a motor vehicle, by detecting a movement of a target, for example a hand or a foot of a user. Technical field

[0002] This disclosure relates to the field of managing access to a motor vehicle. Prior art

[0003] It is known to use radio frequency signals to control the opening of a motor vehicle door, for example a trunk door. A radio frequency signal is an electromagnetic signal comprising a carrier with a frequency ranging for example between 3 kHz and 300 GHz but most often between 5 and 30 GHz in automotive applications.

[0004] There are, in particular, gesture detection methods used for controlling a vehicle opening. In such a method, a radiofrequency signal is transmitted towards a target and the analysis of a return radiofrequency signal makes it possible to recognize a predetermined gesture made by the target.

[0005] It is also known to use a pulsed radiofrequency signal (as opposed to a continuous signal) having so-called radiofrequency pulses, i.e. whose carrier frequency belongs to a wide radiofrequency spectrum. The use of this type of signal makes it possible in particular to have, in addition to information on movement, information on the distance between a target and a device for transmitting and receiving the radiofrequency signal.

[0006] The detection of the predetermined gesture in a considered zone controls the opening or closing, respectively the locking or unlocking of an opening of the vehicle.

[0007] It may happen that the predetermined gesture is confused, during the detection process, with involuntary gestures such as the steps or stamping of a walker moving near the vehicle.

[0008] It is therefore known to use several signal processing devices and methods to discriminate these involuntary gestures during detection.

[0009] However, discrimination requires additional hardware resources capable of implementing complex algorithms.

[0010] An objective of the present invention is to propose a method and a device for detecting gestures intended for controlling an opening of a motor vehicle, which require few hardware resources and perform satisfactory discrimination of involuntary gestures. Summary

[0011] To this end, the present document relates to a gesture detection method intended for controlling an opening of a motor vehicle of reference frame Rv, said reference frame Rv having as its origin a point of the vehicle, said opening being capable of being moved using an actuator, said method comprising the steps consisting of: (a) transmit, using at least one transmitter, a radiofrequency signal called the transmitted signal, intended to propagate to a target, (b) receiving, using at least one receiver, a radiofrequency signal called a return signal, coming from said target, (c) from the return signal, calculate an angular amplitude of the moving target in an analysis plane of the reference frame Rv, said analysis plane being parallel to a plane on which the wheels of the vehicle rest, (d) comparing said angular amplitude to a threshold angle, to determine whether a movement of the target is voluntary or not, a voluntary movement being associated with an angular amplitude less than the threshold angle, (e) from the return signal, implement gesture recognition to detect when the moving target performs a predetermined gesture intended to control an opening of the opening and / or an unlocking of the opening, (f) if the predetermined gesture is detected, and if the gesture is determined to be voluntary, generate a detection signal intended to control the opening of the opening and / or the unlocking of the opening.

[0012] The invention thus makes it possible to consolidate a detection of a desire to access the vehicle, by cross-referencing information on the detection of a predetermined gesture with information on the angular amplitude of the movement. The angular amplitude information thus makes it possible to eliminate false positives in the detection of the predetermined gesture, which may correspond to a gesture close to the predetermined gesture made by chance by a simple walker moving near the vehicle.

[0013] It is obviously understood that the at least one transmitter and the at least one receiver can be formed together by at least one transceiver, the transmission and reception then sharing at least one transmission and reception antenna.

[0014] Angular amplitude is defined as the sum of the absolute values ​​of the angle variations of the moving target between two detection times. The angular amplitude is referred to as Aa in the rest of the document.

[0015] For illustration purposes, in the case of a monotonic movement (i.e. in a single trigonometric direction), the angular amplitude Aa is equal to the absolute value of the difference between: - an angle of the target at a detection start time, and - an angle of the target at an end of detection time.

[0016] In the case of a non-monotonic movement (i.e. presenting variations in trigonometric direction), the angular amplitude Aa is equal to the sum of the absolute values ​​of the variations in angle of the target between each point of inflection.

[0017] The discrimination of involuntary movements (steps (c) and (d)) is typically carried out in an analysis zone in the form of a portion of a sphere located outside the vehicle.

[0018] For example, if one wishes to discriminate movements made at the rear of the vehicle, at the bumper of a vehicle, the discrimination of involuntary movements is typically carried out in an analysis zone taking the form of a portion of a sphere, with the sphere centered on the bumper and said portion of the sphere located outside the vehicle. This is for example a half-sphere located outside the vehicle and delimited by a plane passing through the bumper. Preferably, the portion of the sphere is at most a half-sphere, generally a smaller volume.

[0019] By restricting the analysis area to a plane of interest parallel to a plane on which the vehicle's wheels rest, and therefore by restricting the discrimination parameters to angles in this plane of interest (preferably a horizontal plane), a satisfactory determination of the voluntary or involuntary nature of a movement is made, while minimizing the complexity of the calculation algorithms.

[0020] For illustration purposes, in the case of a vehicle with wheels resting on a “flat” road, the analysis plane is parallel to the horizontal plane of the terrestrial reference frame.

[0021] It may also be provided that the analysis plane is a plane orthogonal to a plane on which the vehicle's wheels rest.

[0022] In the remainder of this document, angles are understood as trigonometric angles, that is, angles that can be positive, negative, or negative.

[0023] The target movement can be determined as voluntary in step (d) if the angle variation is less than or equal to a maximum value, here the threshold angle, hereinafter referred to as as.

[0024] In other words, the target movement can be determined as voluntary in step (d) if the movement describes an angular amplitude Aa less than or equal to as.

[0025] In this way, involuntary movements with large angular amplitudes in the analysis plane are discriminated, i.e. movements whose angular amplitude Aa is greater than as.

[0026] A threshold angle of 90 degrees makes it possible, for example, to discriminate a movement corresponding to a walking movement of a user along the motor vehicle: the angular amplitude Aa is then greater than the threshold angle given that the movement corresponds to an angular amplitude Aa close to TT radians or 180°.

[0027] The threshold angle can be between 70 degrees and 120 degrees, preferably equal to 90 degrees.

[0028] Step (c) may further comprise calculating a first distance between the motor vehicle and the target in the analysis plane, the movement of the target being determined as voluntary in step (d) if further the first distance is less than or equal to a threshold distance.

[0029] In other words, the target movement can be determined as voluntary in step (d) if the target is within an area bounded by the determined vehicle area and a circular arc of radius equal to the threshold distance in the azimuth plane.

[0030] In this way, involuntary movements located at a great distance from the determined area of ​​the vehicle, i.e. at a distance greater than the threshold distance, are discriminated.

[0031] Movements close to the vehicle's determined area, i.e. at a distance less than or equal to the threshold distance, are considered voluntary.

[0032] The threshold distance can be between 10 cm and 50 cm.

[0033] The threshold distance can be equal to 50 cm.

[0034] The transmitted signal may be a pulsed signal comprising a carrier modulated by a sequence of pulses.

[0035] The signals emitted by the transmitter are emitted towards the outside of the vehicle and, preferably, into a detection zone located at the rear of the motor vehicle.

[0036] The transmitted signal may be a radio frequency signal. A radio frequency signal is a frequency electromagnetic signal whose carrier frequency is between 3 kHz and 300 GHz. The carrier frequency may be between 5 GHz and 30 GHz, for example between 5 GHz and 10 GHz.

[0037] The signal may be an ultra-wideband signal.

[0038] An ultra-wideband (or UWB) signal is an electromagnetic signal that is characterized by very short pulses (e.g., on the order of a few nanoseconds) and a very wide bandwidth (e.g., greater than 500 MHz or even more than 1 GHz). The pulses are so short that they have a duration on the order of a few periods of the carrier frequency f, which means that the signal can have a considerably wider bandwidth than conventional signals. A UWB signal also has very low transmitted energy. This type of signal is suitable for use in environments with a lot of radio noise or interference.

[0039] The transmitter and receiver may be located in a single transmitting and receiving device. The transmitter and receiver may be formed by a single radio frequency antenna.

[0040] Multiple transmitters and multiple associated receivers can also be used, the transmitters (and associated receivers) can be located in areas of the vehicle separated from each other.

[0041] This document also relates to a system for managing the opening and / or unlocking of an opening intended to be mounted on a motor vehicle, and configured for implementing the steps of the method according to the invention, and which comprises: at least one first transmission-reception module comprising at least one radiofrequency antenna, said first transmission-reception module being intended to transmit the transmitted signal and to receive the return signal, and an electronic management module comprising a computer provided with at least one processor and at least one memory, said processor having access to the memory to read the steps stored in the memory.

[0042] The calculator can be, for example, a chip.

[0043] The management system may further include a transceiver device carried by the user.

[0044] The transmitting-receiving module can be, for example, an anchor.

[0045] The transmitter-receiver device carried by the user can be, for example, a remote control (or "keyfob" in English).

[0046] For example, the transmitter-receiver device can be a remote control, a badge or a smartphone with a dedicated application.

[0047] Examples of signal processing are described below, making it possible to characterize the movement of the target, in particular when the emitted signal is a pulse signal comprising a carrier modulated by a sequence of pulses. These examples of data processing are given as examples, and are in no way limiting.

[0048] The transmitter may be said at least one radiofrequency antenna of the first transceiver module.

[0049] The receiver may be an additional radio frequency antenna included in the first transceiver module.

[0050] The method according to the invention, and in particular steps (c) and (d) of determining an angular amplitude, can be carried out by the computer according to one of the following two algorithms: a first algorithm called the “radar” algorithm or a second algorithm, called the “ranging” algorithm.

[0051] In "radar" or "ranging" algorithms, the transmitted and received signals are ultra-wideband frames (series of pulses) and the management system includes at least two radiofrequency antennas.

[0052] In the case of the "ranging" algorithm, the target is a transmitter-receiver device. The transmitted signal propagates to this transmitter-receiver device where it triggers the transmission of the return signal which returns to the receiver of step (b). In other words, the target is then a transmitter-receiver device worn by a user, and the angular amplitude is calculated from a two-way communication between the target and the transmitter and / or the receiver. The return signal is a signal generated by the target in response to the reception of the transmitted signal.

[0053] With the “ranging” algorithm, it is the content of the ultra wideband frames which will be used to determine the angular amplitude Aa.

[0054] Frames include several fields including a "Scrambled Timestamp Sequence" (STS) field and a "Synchronization" (SYNC) field.

[0055] In the "ranging" algorithm, step (a) of the method is performed in response to a step (aO) of receiving an initial signal transmitted by the transceiver device.

[0056] In this way, the "ranging" algorithm begins when the receiver mentioned in step (b) receives this initial signal which allows a pairing between the receiver and the transmitter-receiver device worn by the user.

[0057] In other words, the transceiver device transmits the first frame which initiates communication.

[0058] Additionally, in the “ranging” algorithm, for each radio frequency antenna, step (c) includes the substeps of: (c1) from the STS field of the return frame, calculate the evolution of the phase value <P, (c2) calculate an arrival angle a corresponding to an angle of the moving target in the reference frame Rv, using the following formula: [Math. 1] a = sin^C- d^ with Acp the phase shift between the signals received by the two radiofrequency antennas, A the wavelength of the signal, d the distance between the two radiofrequency antennas, and (c3) deduce the angular amplitude Aa of the moving target.

[0059] In the case of the "radar" algorithm, the emitted signal is reflected on the target and returns to the receiver of step (b) in the form of the return signal. The target is preferably a part of the user's body, such as a hand or a foot of the user. In other words, the target is then a part of a user's body and the angular amplitude is calculated from the return signal which is a reflection of the emitted signal on the target. For example, the target can be a hand or a foot of a user.

[0060] According to the “radar” algorithm, for each radiofrequency antenna, step (c) may include the sub-steps consisting of: (c1 ') amplify and demodulate the return signal using a mixer so as to extract signals l(t) and Q(t) defining two in-phase and quadrature-phase components respectively, (c2') obtain sampled data l(t) and Q(t) corresponding to a time sampling of the signals l(t) and Q(t), (c3') extracting, from the sampled data l(ti) and Q(t), those relating only to portions of the return signal, for which a time difference between the reception of each portion of the return signal and the emission of a corresponding pulse of the emitted signal, is included in a predetermined interval (this time interval corresponding in practice to an interval of distances to the target), (c4') for each sampling instant t, calculate a modulus of the extracted data l(ti) and Q(t), noted |CI R(t)| , corresponding to the amplitude of the demodulated return signal, and of value equal to the square root of l2 (ti)+Q 2 (t), (c5') searching, on the calculated |CIR(ti)| data, and successively for each pulse of the emitted signal, for the presence of a peak of amplitude greater than or equal to a predetermined threshold, the first detection of such a peak corresponding to the identification of the start of a movement of the target, the instant tj associated with such a peak being recorded and a pulse of index k of the emitted signal being associated with the first detection of such a peak, (c6') apply a fast Fourier transform on the complex data CIR(tj) of the data |CIR(tj)| obtained to move into the frequency domain and obtain the data |CI R(vj) | , Vj being the frequency associated with the instant tj, (c7') upon detection of a data item |CI R(vj)| greater than a threshold amplitude, calculate the phase cp(k) of the demodulated return signal using the values ​​I and Q associated with said instant tj of the peak, using the following formulas: • if l(tj) >0, then cp(k) = arctan (Q(tj) / I(tj)), • if I (tj) <0 and if Q(tj) <0, then cp(k) = arctan (Q(tj) / I (tj)) - TT, and • if I (tj) <0 and if Q(tj) >0, then cp(k) = arctan (Q(tj) / I (tj)) + TT, (c8') calculate the evolution of the phase value <p, pour les impulsions d’indice k+n suivantes du signal émis, (c9') calculate, continuously until the detection of a data |CIR(Vj)| lower than the threshold amplitude, an arrival angle a corresponding to an angle of the target moving in the analysis plane relative to a point arranged in the middle of the two antennas, using the equation Math. 1, and (c10') deduce the angular amplitude Aa of the moving target.

[0061] Step (c5') can be performed by a high-pass filter on the calculated |CI R(t)| data.

[0062] In this way, only the relevant sampling instants are selected by discriminating the sampling instants tj with ij, for which the amplitude is low, i.e. the sampling instants for which there is no or little movement.

[0063] Alternatively, the arrival angle a can correspond to an angle of the moving target in the analysis plane relative to one of the two antennas, the distance d between the two antennas being negligible.

[0064] Step (e) of implementing gesture recognition may also use a known “radar” type algorithm, exploiting a reflection on the target, or “ranging” type algorithm, exploiting two-way communication with the target. Preferably, steps (c) to (e) use the same type of “radar” or “ranging” algorithm.

[0065] In the case of “radar” type gesture detection, the evolution of the position of the target can be followed via monitoring of the phase values ​​as obtained in step (c8') described above.

[0066] Step (f) consists of generating a detection signal intended to control the opening or unlocking of the opening, when it is determined both that the predetermined gesture has been performed and also that the movement corresponding to this gesture is voluntary, since it has an angular amplitude less than a predetermined threshold angle. This detection signal is sent for example to a control module of an actuator capable of moving the opening from a closed position to an open position, respectively from a locked position to an unlocked position.

[0067] Step (f) may comprise controlling an angular degree of opening of the opening, as a function of the angular amplitude Aa of the moving target.

[0068] The receiver may comprise a matrix of at least two receiving antennas intended to receive the return signal, at least one of the two receiving antennas being able to be a transmitting and receiving antenna further configured to transmit said transmitted signal, the receiver being configured to determine an angle of incidence of the return signal from a time offset between the respective instants of reception of the return signal by each of said receiving antennas.

[0069] In this configuration, the control method can combine the “radar” and “ranging” algorithms as follows: steps (c1 ') to (c6') are carried out then upon detection of a data item |CIR(Vj)| greater than a threshold amplitude, steps (c1) to (c3) are carried out.

[0070] The management system may further comprise a second transceiver module for transmitting a second transmitted signal and receiving a second transmitted signal, the first and second transceiver modules each being configured to determine their respective distance to the target, the angular amplitude being calculated by triangulation and from a known distance between the first and second transceiver modules.

[0071] In this configuration, step (c) of the method comprises the steps of: (c1”) for each transceiver module, calculate the angle of arrival of the return signal, (c2”) deduce the distance between the target and each transceiver module, (c3”) deduce by triangulation the exact position of the target in the analysis plane, and (c4”) deduce the angular amplitude Aa of the moving target.

[0072] The arrival angle at steps (c3), (c10') and (c4”) can be deduced from a correspondence table with the phase shift value Acp, the correspondence table being produced by measurements carried out upstream of the opening control process.

[0073] This document also relates to a motor vehicle equipped with a movable opening, capable of being moved by the actuator between an open position and a closed position, characterized in that it comprises a system for managing the opening and / or unlocking of said opening according to the aforementioned type.

[0074] The vehicle may further comprise a lock for the opening capable of being in a locked or unlocked position and respectively prohibiting or authorizing opening of the opening, said lock being able to be controlled by the management system.

[0075] The lock can be, for example, a latch.

[0076] The disclosed features may optionally be implemented independently of each other or in combination with each other. Brief description of the drawings

[0077] Other features, details and advantages will become apparent upon reading the detailed description below, and upon analyzing the attached drawings, in which:

[0078] [Fig. 1] is a schematic view of a motor vehicle according to an embodiment of the present document,

[0079] [Fig. 2] is a schematic view of the rear of the motor vehicle of Figure 1 in the analysis plane which is a horizontal plane with a target at a first instant,

[0080] [Fig. 3] illustrates the different stages of the process according to the “radar” algorithm,

[0081] [Fig. 4] is a schematic view of Figure 2 with a target at a second time, and

[0082] [Fig. 5] schematically illustrates the rear of a motor vehicle in a section following the analysis plan according to this document.

[0083] [Fig. 6] illustrates the different stages of a method according to the invention, implementing triangulation. Description of the embodiments

[0084] Figure 1 is a schematic view of a motor vehicle according to one embodiment of the present document.

[0085] A motor vehicle 1 comprises a movable opening 2, capable of being moved by the actuator 3 between a fully open position, a fully closed position and at least one partially open intermediate position, the vehicle comprising a system for managing said opening 2.

[0086] A reference point (O, X, Y, Z) is associated with a reference frame Rv of the motor vehicle 1, the origin O being located at the center of the rear bumper 8 of the vehicle 1.

[0087] Figure 2 is a schematic view of the rear of the motor vehicle of Figure 1 in the analysis plane which is a horizontal plane.

[0088] The analysis plan here is therefore the (OXY) plan.

[0089] The management system comprises a transmission-reception module 4 comprising a first and a second radiofrequency antenna 4a, 4b separated by a known distance d, and an electronic management module comprising a computer.

[0090] The first antenna 4a is intended to emit a transmitted signal 10 which propagates towards the target 5 (initially located at point M at a first instant) and the two antennas 4a, 4b are each intended to receive a return signal 12a, 12b which is a reflection of the transmitted signal 10 on the target 5.

[0091] The calculator includes within it a processor and a memory, the processor having access to the memory to read the steps stored in the memory and is capable of generating an output signal making it possible to control the actuator 3.

[0092] Figure 3 illustrates the different steps of the method according to the invention, in which the angular amplitude of the movement is determined according to the “radar” algorithm.

[0093] This method makes it possible to control said opening 2 by detecting a movement of a target 5. In the example illustrated, the target 5 is a part of a user's body.

[0094] During a step EA (step (a) as mentioned above), the first radiofrequency antenna 4a emits the emitted signal 10, which propagates to the target 5. This emitted signal 10 is an ultra-wideband pulse signal, comprising a carrier modulated by a sequence of pulses, and characterized by pulses that are very short in time (for example of the order of a few nanoseconds) and a very wide bandwidth (for example greater than 500 MHz, or even more than 1 GHz).

[0095] In a step EB (step (b) as mentioned above), the transmitted signal 10 is reflected on the target 5 and a return signal 12a, 12b is received by each antenna 4a, 4b respectively. Here, the antenna 4a is therefore a transmitting and receiving antenna, while the antenna 4b is a receiving antenna.

[0096] Upon receipt of the return signal 12a, 12b, the target forms an angle of incidence (i.e. arrival) aa, respectively ab on each antenna 4a, respectively 4b.

[0097] In an EC step (step (c) as mentioned above), the angular amplitude of the moving target in the horizontal plane (OXY) is calculated using the calculator.

[0098] Reference is now made to Figure 4 which represents target 5 in the (OXY) plane at a second instant. Between the first and second instants, target 5 moves from point M to point N during its motion.

[0099] At the first instant, the target at point M forms an angle a with the point located in the middle of a straight segment connecting antenna 4a and antenna 4b, i.e. at point O. In other words, angle a is the angle formed by the half-lines { [OX) ; [OM]}.

[0100] At the second instant, the target at point N forms an angle a' with the point located in the middle between antenna 4a and antenna 4b, i.e. at point O. In other words, angle a' is the angle formed by the half-lines { [OX) ; [ON]}.

[0101] The angular amplitude Aa corresponds to the sum of the absolute values ​​of the angles a and a': Aa = |a| + |a'| .

[0102] In order to determine this angular amplitude Aa, for each antenna 4a, 4b, step EC of the method comprises several sub-steps.

[0103] During a sub-step EC1', the return signal 12a, 12b is amplified and demodulated and signals l(t) and Q(t) defining the two in-phase and respectively in-phase quadrature components are extracted using a mixer.

[0104] During a sub-step EC2', sampled data l(t) and Q(t) are obtained corresponding to a time sampling of the signals l(t) and Q(t).

[0105] During a sub-step EC3', the sampled data l(ti) and Q(t) are extracted from those relating only to portions of the return signal, for which a time difference between the reception of each portion of the return signal and the emission of a corresponding pulse of the emitted signal is less than or equal to one or more thresholds.

[0106] During a sub-step EC4', for each sampling instant ti, we calculate a modulus of the extracted data l(ti) and Q(t), noted |CIR(ti)|, corresponding to the amplitude of the demodulated return signal, and of value equal to the square root of l 2 (ti)+Q 2 (t).

[0107] During a sub-step EC5', we search EC5', on the calculated data |CIR(ti)|, and successively for each pulse of the emitted signal, for the presence of a peak of amplitude greater than or equal to a predetermined threshold, the first detection of such a peak corresponding to the identification of the start of a movement of the target, the instant tj associated with such a peak being recorded and a pulse of index k of the emitted signal being associated with the first detection of such a peak.

[0108] During a sub-step EC6', a fast Fourier transform is applied to the complex data Cl R(tj) of the data |CI R(tj)| obtained to move into the frequency domain and obtain the data |CIR(Vj)|, Vj being the frequency associated with the instant tj.

[0109] During a sub-step EC7', upon detection of a data item |CIR(Vj)| greater than a threshold amplitude, the phase cp(k) of the demodulated return signal is calculated using the values ​​I and Q associated with said instant tj of the peak, using the following formulas: • if l(tj) >0, then cp(k) = arctan (Q(tj) / I(tj)), • if I (tj) <0 and if Q(tj) <0, then cp(k) = arctan (Q (tj) / l (tj)) - TT, and • if I (tj) <0 and if Q(tj) >0, then cp(k) = arctan (Q (tj) / l (tj)) + TT.

[0110] During a sub-step EC8', we calculate the evolution of the phase value <p, pour les impulsions d’indice k+n suivantes du signal émis.

[0111] During a sub-step EC9', we calculate, continuously until the detection of a data |CIR(tj)| less than the threshold amplitude, an arrival angle a, a' corresponding to an angle of the target in motion in the analysis plane, using the equation Math.1.

[0112] In a sub-step EC10', the angular amplitude Aa of the moving target is deduced.

[0113] In a step ED of the method, the angular amplitude Aa is compared to a threshold angle as, to determine whether the movement of the target is voluntary or not, a voluntary movement being associated with an angular amplitude Aa less than the threshold angle.

[0114] During a step RG of the method, gesture recognition is implemented to detect when the moving target performs a predetermined gesture intended to control an opening and / or an unlocking of the opening. This step RG is implemented after the step EB of receiving the return signal. It can be implemented in parallel with the steps EC and ED of calculating an angular amplitude and comparing it to a threshold. If necessary, it can combine certain sub-steps with those of the step EC of calculating an angular amplitude. Thus, in an advantageous but non-limiting manner, the step RG of gesture detection can implement a tracking of phase values ​​as obtained at the end of the sub-step EC8'.

[0115] During a step EE of the method, if the gesture is determined to be voluntary (result “Y”) and if the predetermined gesture is recognized (Y), a detection signal is generated, which is intended to control an opening and / or an unlocking of the opening 2, using the actuator 3.

[0116] Otherwise, the process stops (step EE'). This corresponds to cases where the predetermined gesture is not detected and to cases where the predetermined gesture is detected but the movement is determined to be involuntary.

[0117] For as=90°, the movement of the target in Figure 4 is considered voluntary, because Aa < as. In other words, the movement of the target is discriminated, because the angle variation between points M and N describes an angle smaller than the threshold angle as.

[0118] Figure 5 illustrates an embodiment in which the opening management system comprises a first and a second transceiver module 50, 52 arranged at the rear bumper 8 of the vehicle and at a distance L1 from each other. Each of the first and second transceiver modules 50, 52 comprises at least one transmitter and at least one receiver as described above.

[0119] The target 5 is located at point P, the reference point of the first transmission module 50 is point Q and the reference point of the second transmission-reception module 52 is point R. Point Q is located at a distance L1 from point R.

[0120] The reference points Q and R are the midpoints of the intersections of the first and second transceiver modules 50, 52 respectively with the axis [OY].

[0121] Figure 6 illustrates the different steps of the method in this embodiment.

[0122] The method of Figure 6 differs from that of Figure 3 in that the EC step of the method comprises different substeps.

[0123] During a sub-step EC1”), for each transceiver module 50, 52, the angle 0, v of the return signal formed by the segment of length L1 (i.e. the segment [QR]) and the segment between the target 5 and the corresponding transceiver module (i.e. the segment [QP] for the first transceiver module 50 and the segment [RP] for the second transceiver module 52) is calculated.

[0124] During a sub-step EC2”, the distance L2, L3 (corresponding to [QP] for L2 and [RP] for L3) between the target 5 and each corresponding transceiver module 50, 52 is deduced.

[0125] In sub-step EC3”, the exact position of target 5 in the analysis plane is deduced by triangulation.

[0126] In a sub-step EC4”, we deduce the angular amplitude Aa of the moving target 5.

Claims

Claims

1. Method for detecting gestures intended for controlling an opening (2) of a motor vehicle (1) of reference frame Rv, said reference frame Rv having as its origin a point (O) of the vehicle, said opening (2) being capable of being moved using an actuator (3), said method comprising the steps consisting of: (a) transmitting (EA), using at least one transmitter (4a), a radiofrequency signal called transmitted signal (10), intended to propagate to a target (5), (b) receiving (EB), using at least one receiver (4a, 4b), a radiofrequency signal called return signal (12a, 12b), coming from said target (5), (c) from the return signal (12a, 12b), calculating (EC) an angular amplitude of the moving target in an analysis plane of the reference frame Rv, said analysis plane being parallel to a plane on which the wheels of the vehicle (1) rest, (d) comparing (ED) said angular amplitude (Aa) with a threshold angle (as), to determine whether a movement of the target (5) is voluntary or not, a voluntary movement being associated with an angular amplitude (Aa) less than the threshold angle (as), (e) from the return signal (12a, 12b), implement gesture recognition (RG) to detect when the moving target performs a predetermined gesture intended to control an opening of the opening (2) and / or an unlocking of the opening (2), (f) if the predetermined gesture is detected, and if the gesture is determined to be voluntary, generate (EE) a detection signal intended to control the opening of the opening (2) and / or the unlocking of the opening (2).

2. Control method according to the preceding claim, in which the threshold angle (as) is between 70 degrees and 120 degrees, preferably equal to 90 degrees.

3. Control method according to one of the preceding claims, wherein step (c) further comprises calculating a first distance between the motor vehicle (1) and the target (5) in the analysis plane, the movement of the target (5) being determined as voluntary in step (d) if in addition the first distance is less than or equal to a threshold distance.

4. Control method according to one of the preceding claims, in which the target (5) is a part of the body of a user and the angular amplitude (Aa) is calculated from the return signal (12, 12b) which is a reflection of the emitted signal (10) on the target (5).

5. A control method according to any one of claims 1 to 3, wherein the target (5) is a transmitter-receiver apparatus and the angular amplitude (Aa) is calculated from a two-way communication between the target (5) and the transmitter (4a) and / or the receiver (4a, 4b).

6. System for managing the opening and / or unlocking of an opening (2) intended to be mounted on a motor vehicle (1), and configured for the implementation of each of the steps of the method according to one of the preceding claims, characterized in that it comprises: at least one first transmission-reception module (50) comprising at least one radiofrequency antenna, said first transmission-reception module (50) being intended to transmit the transmitted signal and to receive the return signal (12a, 12b), and an electronic management module comprising a computer provided with at least one processor and at least one memory, said processor having access to the memory to read steps stored in the memory.

7. Management system according to the preceding claim, in which the first transmission-reception module (4) comprises a matrix of at least two receiving antennas intended to receive the return signal (12a, 12b), at least one of the two receiving antennas being able to be a transmission and reception antenna further configured to transmit said transmitted signal, the first transmission-reception module (50) being configured to determine an angle of incidence of the return signal from a time offset between the respective instants of reception of the return signal by each of said receiving antennas.

8. Management system according to claim 6 further comprising a second transceiver module (52) for transmitting a second transmitted signal and receiving a second transmitted signal, the first and second transceiver modules (50, 52) each being configured to determine their respective distance to the target (5), the angular amplitude being calculated by triangulation and from a known distance (L1) between the first and second transceiver modules (50, 52).

9. Motor vehicle (1) provided with a movable opening (2), capable of being moved by the actuator (3) between an open position and a closed position, characterized in that it comprises a system for managing the opening and / or unlocking of said opening (2) according to claims 6 to 8.

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