Method for determining the opening of a vehicle door and gesture detection system implementing this method

Abstract

A method for determining the position of a trunk lid of a vehicle equipped with a radar antenna configured and positioned to emit a pulsed signal in a substantially vertical direction, comprising the following steps: - a preliminary step to determine, by calculation or measurement, a range of possible distances between the radar antenna and the trunk lid, - emission of a pulsed signal, - reception of a return pulsed signal, - measurement of a time delay between a pulse of the return pulsed signal and a corresponding pulse of the emitted pulsed signal, - estimation of a distance corresponding to the measured time delay, knowing the speed of the signal, - if the estimated distance is within the range of possible distances between the radar antenna and the trunk lid,Therefore, it is considered to be the distance separating the radar antenna from the trunk opening. (See Figure 4 in the summary.)

Description

Title of the invention: Method for determining the opening of a vehicle door and gesture detection system implementing this method

[0001] This disclosure relates to a method for determining the opening of a vehicle door and a gesture detection system implementing this method. Technical field

[0002] This disclosure falls within the domain of access management to a motor vehicle. Previous technique

[0003] It is known to use radio frequency signals to control the opening of a motor vehicle door. A radio frequency signal is an electromagnetic signal comprising a carrier with a frequency, for example, between 3 kHz and 300 GHz, but most often between 5 and 20 GHz in automotive applications.

[0004] In particular, there are gesture detection methods used for controlling a vehicle opening. In such a method, a radio frequency signal is emitted towards a target, and the analysis of a return radio frequency signal makes it possible to recognize a user's foot performing a predetermined gesture.

[0005] It is also known to use a pulsed radio frequency signal (as opposed to a continuous signal) exhibiting so-called radio frequency pulses, that is, pulses whose carrier frequency belongs to the radio frequency spectrum. In other words, the radio frequency signal exhibits pulsed modulation. The use of this type of signal makes it possible, in particular, to determine the distance between a target and a device for transmitting and receiving said pulsed radio frequency signal.

[0006] Source radio frequency signal pulses are emitted, and corresponding return radio frequency signal pulses are detected on an amplitude signal, time-sampled by an analog-to-digital converter. The time-sampling frequency defines sampling windows and thus the accuracy of the measurement of the time taken by the pulse to travel to and from the target and back. To increase measurement accuracy, the sampling frequency should be as high as possible. In practice, accuracy is generally achieved on the order of tens of centimeters, for example, between 10 and 20 cm, for example, approximately 15 cm.

[0007] Motorized openings, most often trunk lids, are increasingly common on vehicles. If an obstacle is detected near the opening, only a partial opening of the opening should be ordered. To open the opening without it encountering an obstacle, it is often necessary to know the percentage of opening the opening requires.

[0008] For cost reasons, opening motors are often on / off type actuators that do not provide an indication of the percentage of opening of the controlled element. If the motor allows the position of the controlled opening to be determined, then for safety reasons, it is advantageous to verify the opening percentage provided by the motor using a redundant system.

[0009] The purpose of this disclosure is to provide a method for determining the degree to which a vehicle opening, such as a trunk lid, is open. This determination can then be used in an opening command to prevent the opening from colliding with a previously detected obstacle. Summary

[0010] The present disclosure then proposes a method for determining the position of a trunk opening of a vehicle, the vehicle having a radar antenna configured and positioned so as to emit a pulsed signal along a line of sight, the line of sight being oriented in a substantially vertical direction when the vehicle is supported on a substantially horizontal ground, the vertical direction corresponding to a direction perpendicular to the ground on which the vehicle is located.

[0011] According to this disclosure, this process comprises the following steps: -a- emission of at least one emitted pulse signal, -b- reception of at least one return pulse signal, -c- measurement of a time shift between a pulse of the return pulse signal considered and a corresponding pulse of the emitted pulse signal, -d- estimation of a distance corresponding to the measured time shift knowing the speed of the signal, -e- if the estimated distance is included in a range of possible distances that can separate the radar antenna and the trunk opening, then it is considered to be the distance separating the radar antenna from the trunk opening.

[0012] The features described in the following paragraphs may optionally be implemented independently of each other or in combination with each other:

[0013] - the radar antenna is a bidirectional antenna (one direction being used to determine the position of a trunk opening, the other direction being used to implement gesture detection as described below);

[0014] - the radar antenna is positioned closer to the ground than to the trunk lid in the closed;

[0015] - a preliminary step to determine by calculation or by measurements a range of possible distances between the radar antenna and the trunk opening,

[0016] - the return pulse signal is time-sampled by a converter analog digital; and / or

[0017] - the method further comprises a step of determining the relative opening of the trunk opening.

[0018] According to another aspect, a computer program is proposed that includes instructions for implementing all or part of a process as defined herein when this program is executed by a processor / computer. According to another aspect, a non-transient, computer-readable recording medium is proposed on which such a program is recorded.

[0019] According to another aspect, a computer is proposed for installation in a motor vehicle comprising at least one processor and at least one memory, characterized in that it is configured for the implementation of steps -c- and following of a method as defined herein.

[0020] According to another aspect, a trunk opening management system intended to be installed in a motor vehicle is proposed, characterized in that it comprises: - a transmission and reception module comprising at least one radar antenna, and configured to transmit and receive a pulsed radio frequency signal, and - an electronic management module comprising a computer as defined above.

[0021] According to one embodiment, in this safe opening management system, the radar antenna of the transmit and receive module may be intended to transmit omnidirectionally, and the system advantageously further comprises at least one directional antenna intended to receive directionally.

[0022] According to another aspect, a gesture detection system for a motor vehicle is proposed, comprising: - a safe opening management system as described above, - a data extraction unit, configured to receive as input data from the transmission and reception module relating to a pulsed radiofrequency signal received by said module, and to extract therefrom first data relating to a first range of distances to the radar antenna of the transmission and reception module, and to further extract therefrom second data relating to a second range of distances to the radar antenna of the transmission and reception module; and - a gesture detection unit, configured to receive input data relating to at least one radio frequency signal received by the transmission and reception module of the trunk opening management system, and to deduce information relating to the detection of a predetermined gesture, said gesture being intended to control the opening of a door of the motor vehicle; said data relating to at least one received radio frequency signal comprising at least said first data, extracted by the data extraction unit; and in which the safe opening management system computer is configured to use said second data extracted by the data extraction unit.

[0023] Implementing such a gesture detection system is particularly advantageous because it combines resources between the trunk opening measurement and gesture detection functions. This resource sharing is made possible by using a pulsed radar signal, which allows data to be extracted from different detection zones. Combining the trunk opening measurement function with other functions using a pulsed signal can be considered, for example, with a secure location function involving bidirectional communication between the vehicle in question and a corresponding badge worn by a user.

[0024] In such a gesture detection system, optionally: - the transmission and reception module comprises at least a first radar antenna and a second radar antenna configured, each to transmit at least one transmitted radiofrequency signal and receive a return radiofrequency signal, and having respective sighting axes inclined at least 30° relative to each other; - the transmission and reception module is configured to transmit a continuous signal using said first radar antenna, and a pulsed signal using said second radar antenna, with the line of sight of said second radar antenna which is oriented along a substantially vertical axis, in use in a motor vehicle having its four wheels resting on a horizontal plane: - the data extraction unit is configured to receive as input data from said second radar antenna, and to extract therefrom the first data relating to a first range of distances to the second antenna, and the second data relating to a second range of distances to the second antenna; - the gesture detection unit is configured to receive said first data as well as data from the first radar antenna, and to deduce therefrom said information relating to the detection of the predetermined gesture; and - The computer of the safe opening management system is configured to receive the aforementioned second data as input, and to deduce information from it relative to a current position of the opening.

[0025] According to a final aspect, a motor vehicle is proposed equipped with a trunk associated with a movable trunk lid between a position allowing access to the trunk from an exterior space of the vehicle and a closed position isolating an interior space of the trunk from the exterior space of the vehicle, characterized in that it includes a trunk opening management system as defined above.

[0026] This vehicle may also include a motorized trunk opening device and a gesture detection device associated with said motorized trunk opening device. Brief description of the drawing

[0027] Other features, details and advantages will become apparent upon reading the detailed description below and analyzing the accompanying drawing showing various figures, in which: Fig. IA

[0028] [Fig. 1A] schematically shows an emitted pulse signal and a return pulse signal that can be used in a process according to this disclosure. Fig. 1B

[0029] [Fig.1B] schematically shows a pulse of emitted impulse signal. Fig. 2

[0030] [Fig.2] schematically shows a pulse of a return pulse signal, sampled over time. Fig. 3

[0031] [Fig.3] schematically shows a matrix grouping values ​​relating to a plurality of impulses. Fig. 4

[0032] [Fig.4] schematically shows a motor vehicle trunk for the implementation of a method according to the present disclosure. Fig. 5

[0033] [Fig.5] schematically shows signal peaks corresponding to trunk opening positions and a user's foot detection. Description of the embodiments

[0034] This disclosure relates to a system and method for managing the opening of a trunk lid 140 of a motor vehicle 100 ([Fig.4]) and aims to determine the opening position (relative or absolute) of the trunk lid 140. This disclosure relates more particularly, but not exclusively, to a trunk 120 having a motorized opening system for its lid, said opening system being controlled, for example, by a user gesture detection.

[0035] It is particularly known to have a system that allows the detection of a user's foot passing under the rear of the vehicle. Such a system ([Fig.4]) most often uses a first radar antenna A1 and a second radar antenna A2, a radar antenna being a device for transmitting and / or receiving radio frequency signals.

[0036] As schematically illustrated in [Fig. 4], for a vehicle trunk equipped with such a system, the radar antenna A1 is, for example, fixed under the trunk and has a viewing axis oriented at approximately 45° towards the ground. This radar antenna emits, for example, a continuous single-frequency signal. The radar antenna A2 is oriented to emit a signal perpendicular to the ground, that is, most often a substantially vertical signal. This second antenna A2 is configured to emit pulsed signals. The viewing axes of the antennas thus form an angle of 45° with each other. This angle value depends on the solid angle of transmission of the antennas. To avoid overlap of the information corresponding to the emissions of the two antennas, an angle of at least 30° between the two viewing axes of the radar antennas A1 and A2 is preferred.

[0037] Such an opening system is, for example, equipped with electronic processing means and comprises - a gesture detection unit, configured to receive as input data relating to said return signals, and to deduce therefrom information relating to the detection of a predetermined gesture, said gesture being intended to control the opening of an opening of the motor vehicle; - a transmit and receive module, including radar antennas A1 and A2, configured to transmit a continuous signal using the first radar antenna A1, and a pulsed signal using the second radar antenna A2: - a data extraction unit, configured to receive as input data from the second radar antenna A2, and to extract therefrom first data relating to a first range of distances to the second antenna, and to further extract therefrom second data relating to a second range of distances to the second antenna; - the gesture detection unit is configured to receive said first data as well as data from the first radar antenna, and to deduce therefrom said information relating to the detection of the predetermined gesture. When it comes to controlling an opening of the opening from a gesture detection, the target is then a user's foot and otherwise the target can be the opening which allows access to the trunk of the vehicle from outside of it as well as its closing as explained below.

[0038] In the remainder of this description, we will mainly be dealing with the second antenna A2 and for this one we will simply refer to it as a pulsed signal emitted and return impulse signal. The second antenna A2 is assumed to be a transmitting and receiving antenna. In [Fig. 1A], a solid-lined curve 11 represents the intensity of the emitted impulse signal as a function of time t. A dashed-lined curve 12 represents the intensity of the return impulse signal as a function of time t.

[0039] Figure 1B illustrates in more detail one of the pulses of the emitted pulsed signal. Each pulse is defined by a carrier and an envelope. The carrier frequency, f2, belongs to the radio frequency spectrum. For example, the carrier frequency is 7.8 GHz. The envelope is defined by a frequency spectrum, the highest value of which, λ, is much lower than f2. For example, λ is less than or equal to f2 / 10. For example, λ is equal to 500 MHz.

[0040] Preferably, the emitted pulse signal is a signal modulated according to the so-called "UWB" modulation technique, for "Ultra Wide Band". This modulation technique is based on the transmission of very short pulses, preferably less than one nanosecond, and over a wide frequency spectrum.

[0041] Similarly, the return impulse signal consists of impulses each defined by a carrier of frequency f2 and an envelope of higher frequency fl.

[0042] To determine the position of the opening, it is necessary to determine the distance separating the radar antenna A2 from the opening. Depending on the emission produced (either downwards only for a unidirectional antenna, or downwards and upwards for a bidirectional antenna) the electromagnetic wave emitted by the radar antenna A2 reaches the opening directly (after passing through the bottom of the trunk) or is reflected off the ground before reaching the opening (after passing through the bottom of the trunk).

[0043] To measure the distance (direct or with reflection) traveled by the emitted impulse signal, a measurement is taken of the time delay between a pulse of the return impulse signal and the corresponding pulse of the emitted impulse signal. In particular, the time delay between the respective amplitude maxima of these two pulses is measured.

[0044] This involves, in particular, measuring a time difference between a reception time tr and an emission time t0, with: - tO the instant of emission by the emission and reception device (radar antenna A2) of a given pulse of the emitted pulse signal, and - the instant of reception by said device of the corresponding pulse of the return pulse signal.

[0045] Here, the return pulse signal is time-sampled by an analog-to-digital converter, preferably within the radar antenna A2. Figure 2 schematically illustrates a pulse of the return pulse signal. time-sampled.

[0046] The sampling frequency of the return impulse signal is denoted f_ech. According to the Shannon criterion, the maximum value that f_ech can take is twice f2, that is to say, the highest frequency of the envelope of the return impulse signal, considered to be equal to the highest frequency of the emitted impulse signal, that is to say fl. Thus, if fl = 500 MHz, we will have a sampling frequency f_ech of 1 GHz.

[0047] The value of the sampling frequency f_ech fixes a sampling window width Atl associated with the temporal sampling of the return impulse signal, with: Atl=l / f_éch.

[0048] The value of Atl gives the margin of error in determining the time delay between a pulse of the return pulse signal and the corresponding pulse of the emitted pulse signal. Considering the speed c of the signal, which is approximately the speed of light in a vacuum, i.e., 3 × 10⁸ m / s, we can obtain the spatial delay d_sp between the transmitting / receiving device, i.e., the radar antenna A2, and the target, i.e., the trunk opening. Just as there is a margin of error in determining the time delay, we obtain a margin of error Adl in determining a spatial delay. Here, we have: Adl = c / (2 * f_ech) A factor of 2 is introduced because the signal travels back and forth between the antenna and the target. With the previous numerical values, Adl is approximately equal to 15 cm.

[0049] The approximate distance d_sp measured therefore corresponds to the distance separating the radar antenna A2 from the trunk opening, with or without reflection on the ground depending on the direction of emission towards the ground or towards the trunk of the emitted pulse signal (if there is no other "reflecting" obstacle between them such as a user's foot) with a margin of error Adl.

[0050] Figure 2 illustrates: - tO corresponding to the instant of emission of a pulse in an emitted pulse signal, - Atl corresponding to the width of a sampling window, and - FR corresponding to a time window receiving the pulse of the return pulse signal corresponding to the pulse of the pulse signal emitted at tO.

[0051] The time tO can be defined from a start time of pulse emission and a pulse repetition frequency. Alternatively, tO can be defined from a time of reception, by the radar antenna A2, of a (very) strong signal. This signal corresponds to a portion of the pulse of the emitted pulsed signal that is detected directly by the radar antenna A2, without having been reflected by the target.

[0052] The determination of the distance d_sp can be carried out by constructing a matrix with the data, as illustrated in [Fig.3]. This matrix is ​​a 3D matrix with: - a first dimension k corresponding to the count of the pulses of the emitted pulse signal, where each emission of a new pulse increments the value of the index k by one unit; - a second dimension, i, corresponding, for each index k, to the time axis divided into sampling windows; and - a third dimension, called S(k,i), corresponding to the absolute value of the amplitude of the signal measured by the radar antenna A2, where appropriate after application of at least one filter to overcome the noise.

[0053] The first and second dimensions together correspond to a folding of the time axis to define a new time origin for each new emission of a pulse of the emitted pulse signal. This folding of the time axis makes it possible to directly obtain, by identifying the time window receiving a peak in the signal's amplitude, the desired time shift (and therefore also the spatial shift d_sp).

[0054] Figure 4 illustrates a vehicle 100 comprising a trunk 120 and a trunk lid 140 shown in dotted lines in three distinct positions: closed, partially open, and fully open. This highly schematic figure also shows the radar antenna A1 and the radar antenna A2.

[0055] As illustrated in [Fig. 4], the radar antenna A2 measures a distance between itself and the trunk lid which is: - DI when the trunk is closed (trunk opening 120 locked for example); - D2 when the trunk opening 140 is in an intermediate position (trunk half-open); and - D3 when the trunk lid 140 is in its maximum open position.

[0056] An original idea for measuring the position of the trunk lid 140 is to isolate, from the return pulse signals, the part of the signal that will allow the position of the trunk lid 140 to be determined.

[0057] It is then proposed to perform a preliminary calibration operation. This operation can be carried out once and for all for the same type of vehicle (same trunk and opening geometry, same radar antenna A2). It is necessary here to determine the values ​​of DI and D3. This determination can be made by simulation or during calibration with a prototype. The distance between the radar antenna A2 and the ground varies very little.

[0058] If the radar antenna A2 emits only towards the ground, it will be necessary to take into account reflection conditions which may differ from one measurement to another.

[0059] If the radar antenna A2 is bidirectional, it will be advantageous to position it so that it is closer to the ground than to the trunk lid in its closed position. The idea here is to clearly distinguish the return pulse signals that have reached the trunk lid 140 from those that have reached another target. In the case of a pulse signal emitted towards the ground, a target located between the ground and the trunk lid 120 will necessarily correspond to a distance d_sp less than that of the closed trunk lid (Dl). By placing a bidirectional radar antenna A2 in a "low" position, that is, closer to the ground than to the trunk lid 140 in the closed position, we also ensure that we can distinguish a return pulse signal peak corresponding to the trunk lid 140 from a return pulse signal peak corresponding to a target (the foot of a user wishing to open the trunk) located between the ground and the radar antenna A2.

[0060] For a radar antenna A2 mounted in a given vehicle, the values ​​of i (see [Fig.3]) corresponding to Dl and D3, respectively il and i3, are then defined during the calibration operation. The calibration operation may consist of determining the values ​​il and i3.

[0061] Thus, when taking a measurement to determine the position of the trunk lid 140, a data matrix such as that in [Fig. 3] is constructed within an electronic unit integrating a computer (or microprocessor) and a memory capable of recording, for example, data corresponding to the emitted pulse signals and the return pulse signals to be analyzed. Electronic analysis means are then provided to detect the presence of a peak for pulses with index values ​​i between i1 (inclusive) and i3 (inclusive). If a peak is detected between these two values ​​i1 and i3 inclusive, then it is considered to be a peak originating from a return pulse signal resulting from a reflection on the trunk lid 140. The index corresponding to this peak must be determined: i2 is then said index.

[0062] The electronic means for determining the opening of the trunk lid can be integrated into a radar antenna (A2 and / or Al) or can be located in an electronic unit separate from the antennas, for example an electronic vehicle control and management unit.

[0063] To determine the proportion of chest openings %_ouv, the following formula can be used, for example: %_ouv=(i2-i 1 ) / (i3-i 1 )* 100

[0064] Fig. 5 schematically illustrates various peaks that can be observed during a measurement of the opening of a trunk lid.

[0065] On the x-axis, the index i from [Fig. 3] has been plotted. A value i_lim is defined for this axis. In this variant, the analysis of the resulting matrix is ​​intended to analyze the peaks observed for i > i_lim. Advantageously, an upper limit i_sup is also determined.

[0066] If a peak is observed for i=i0 <i_lim, alors on considère que ledit pic ne peut pas correspondre à une valeur d’ouverture d’ouvrant de coffre.

[0067] The values ​​il and i3 correspond to the values ​​il and i3 previously defined. We will have: i_lim<=il et i_lim <i3.

[0068] When a peak corresponding to an index i2 (with i2>=i_lim and il<=i2<=i3) is detected, the peak corresponding to this index i2 is considered to result from a reflection on the safe opening 140 and the proportion of opening of the safe %_ouv will then be determined.

[0069] As mentioned above, the signal from radar antenna A2 can also be used for a function other than the one described above for determining the position of the opening 140. The data extraction unit, through calibration, can distinguish the parts of the return signals that relate to the position of the opening from the parts of these signals that relate to another function. This other function could be the gesture detection mentioned above, but it could also be obstacle detection, two-way communication with a badge, etc.

[0070] For the functions of detecting the opening of an opening and of detecting gesture, it is possible to have an omnidirectional transmission / reception with a UWB type signal, a directional reception then being used for the detection of a proportion of opening of the trunk opening (or other opening).

[0071] While, as described, the signal emitted by radar antenna A2 is a pulsed signal, the signal emitted by radar antenna A1 can be a continuous signal. Thus, radar antenna A1 and radar antenna A2 can have a directional transmission / reception of a continuous wave (CW) and, respectively, a directional transmission / reception of a pulsed wave (UWB type). Part of the return signals from the pulsed radar antenna A2 can then be used for gesture detection (corresponding to "near" detection of the antenna), and another part is used for determining the position of an opening.The combination of the analysis of the signals received back by the radar antenna A2 in combination with the analysis of the signals received back by the radar antenna Al is used by the electronic processing means to achieve the detection of a movement, for example a movement of a user's foot, in order to control the opening of a door or window in a manner known to a person skilled in the art. Industrial application

[0072] The present disclosure therefore proposes in an original way to use a transmitter-receiver device to achieve detection of a proportion of opening of an opening, for example of a trunk, rather than using a sensor on an opening actuator.

[0073] This is particularly relevant for a vehicle equipped with a gesture detection system used to control the opening of the relevant door, in particular the trunk. Indeed, such a gesture detection system is typically equipped with a radar antenna which is then also used in an original way to measure the distance between said radar antenna and the corresponding trunk opening.

[0074] In addition, the use of pulse signals (commonly known by the English acronym UWB) makes it possible to avoid providing an additional radar antenna which is used only for measuring the opening of the trunk, but to use an antenna already present in the vehicle for other functions (gesture detection and / or secure location implementing bidirectional communication between the vehicle and a badge worn by a user).

[0075] Information about the trunk lid opening can then be used by a motorized trunk opening control device. This device is known, in particular, to detect an obstacle. Once the obstacle is detected, a maximum opening of the trunk lid can be determined. The power supply to the trunk lid opening control motor will then be cut off as soon as the determined maximum opening is reached.

[0076] The measurement can be carried out with a unidirectional radar antenna but is preferably implemented with a bidirectional radar antenna, or even with transmission using an omnidirectional radar antenna coupled with reception using a directional radar antenna.

[0077] The method proposed here is original in that it focuses only on a portion of a return pulse signal that may correspond to the desired information about the opening of the door or window, and does not take into account the rest of this signal. The relevant portion of the signal is determined during a preliminary calibration step.

[0078] The invention, based on the use of a pulsed radio frequency signal, allows for the sharing of resources with at least one other device, such as a gesture detection device. Advantageously, this sharing is made possible by a data extraction unit configured to be isolated from the portions of the return signal associated with one or the other range of distances to the vehicle.

[0079] The method can be applied to any type of vehicle. It is particularly intended for vehicles with a motorized trunk opening, but other applications on vehicles without a motor for opening the trunk lid can be considered.

[0080] This disclosure is not limited to the embodiments and variants described above, which are provided for illustrative purposes only, but encompasses all variants that the expert in the field will be able to consider within the framework of the protection sought.

Claims

Claims

1. Method for determining a position of a trunk opening (140) of a vehicle (100), the vehicle comprising a radar antenna (A2) configured and positioned so as to emit a pulse signal along a line of sight, the line of sight being oriented in a substantially vertical direction when the vehicle has its wheels resting on a horizontal plane, the method being characterized in that it comprises the following steps: -a- emission of at least one transmitted pulse signal, -b- reception of at least one return pulse signal, -c- measurement of a time difference between a pulse of the return pulse signal considered and a corresponding pulse of the transmitted pulse signal, -d- estimation of a distance corresponding to the measured time difference, knowing the speed of the signal, -e- if the estimated distance is included in a range of possible distances that can separate the radar antenna and the trunk opening,then it is considered to be the distance separating the radar antenna from the trunk opening.,

2. Method according to claim 1, characterized in that the radar antenna (A2) is a bidirectional antenna.

3. Method according to one of claims 1 or 2, characterized in that the radar antenna (A2) is arranged closer to the ground than to the trunk opening (140) in the closed position.

4. Method according to one of claims 1 to 3, characterized in that it comprises a prior step for determining by calculation or by measurements a range of possible distances which can separate the radar antenna (A2) and the trunk opening (140).

5. Method according to one of claims 1 to 4, characterized in that the return pulse signal is sampled in time by an analog-digital converter.

6. Method according to one of claims 1 to 5, characterized in that it further comprises a step of determining the relative opening of the trunk opening (140).

7. Computer program comprising instructions which, when the program is executed by a computer, cause the latter to implement steps -c- and following of a method according to one of the claims- indications 1 to 6.

8. Computer intended to be installed in a motor vehicle comprising at least one processor and at least one memory, characterized in that it is configured for the implementation of steps -c- and following of a method according to one of claims 1 to 6.

9. Trunk opening management system intended to be installed in a motor vehicle, characterized in that it comprises: - a transmission and reception module comprising at least one radar antenna (A2), and configured to transmit and receive a pulsed radiofrequency signal, and - an electronic management module comprising a computer according to claim 8.

10. Trunk opening management system according to claim 9, characterized in that the radar antenna (A2) of the transmission and reception module is intended to transmit omnidirectionally, and in that the system further comprises at least one directional antenna intended to receive directionally.

11. Gesture detection system for a motor vehicle, comprising: - a trunk opening management system according to claim 9 or 10; - a data extraction unit, configured to receive as input data from the transmission and reception module relating to a pulsed radiofrequency signal received by said module, and to extract therefrom first data relating to a first range of distances to the radar antenna of the transmission and reception module, and to further extract therefrom second data relating to a second range of distances to the radar antenna of the transmission and reception module;- a gesture detection unit, configured to receive as input data relating to at least one radiofrequency signal received by the transmission and reception module of the trunk opening management system, and to deduce therefrom information relating to the detection of a predetermined gesture, said gesture being intended to control the opening of an opening of the motor vehicle, said data relating to at least one received radiofrequency signal comprising at least said first data, extracted by the data extraction unit; and in which the computer of the trunk opening management system is configured to use said extracted second data; by the data extraction unit.

12. Gesture detection system according to claim 11, wherein: - the transmission and reception module comprises at least a first radar antenna and a second radar antenna configured, each to transmit at least one transmitted radiofrequency signal and receive a return radiofrequency signal, and having respective sighting axes inclined at least 30° relative to each other;- the transmission and reception module is configured to transmit a continuous signal using said first radar antenna, and a pulsed signal using said second radar antenna, with the line of sight of said second radar antenna which is oriented along a substantially vertical axis, in use in a motor vehicle having its four wheels resting on a horizontal plane: - the data extraction unit is configured to receive as input data from said second radar antenna, and to extract therefrom the first data relating to a first range of distances to the second antenna, and the second data relating to a second range of distances to the second antenna; - the gesture detection unit is configured to receive said first data as well as data from the first radar antenna, and to deduce therefrom said information relating to the detection of the predetermined gesture;and - the calculator of the trunk opening management system is configured to receive said second data as input, and to deduce therefrom information relating to a current position of the opening.;

13. Motor vehicle provided with a trunk associated with a trunk opening movable between a position allowing access to the trunk from a space outside the vehicle and a closed position isolating an interior space of the trunk from the space outside the vehicle, characterized in that it comprises a trunk opening management system according to one of claims 9 or 10.

14. Motor vehicle according to claim 13, characterized in that it comprises a motorized trunk opening device as well as a gesture detection device associated with said motorized trunk opening device.

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