WO2005034393A1 - System for hands free access and for controlling a motor vehicle operations - Google Patents

Abstract

The invention relates to a hands free system for controlling a motor vehicle operations comprising at least one badge (4) and to a control system (6) for access to a motor vehicle which exchange data therebetween for controlling actuators (40) which activate the vehicle operations. In addition said system comprises means (18, 48, 36) using a channel for current transmission through a body for data exchange between the badge (4) and the control system (6) in order to make sure than the initiator of the operation control of the vehicle is an authorised user provided with the badge (4).

Description

 Description HANDS-FREE ACCESS AND FUNCTION CONTROL SYSTEM FOR A MOTOR VEHICLE

[001] The invention relates to a system of access "hands-free" and control functions of a motor vehicle.

[002] A "hands-free" access system to a vehicle allows the user to access the vehicle without, for example, introducing and operating a mechanical key in a lock. Such a system also makes it possible to control the functions of a motor vehicle such as the start function and others. A "hands-free" access system comprises at least one badge and an on-board control system on board the motor vehicle. In this way, the badge wearer and the on-board control system exchange data to activate the vehicle functions, such as unlocking the doors of said vehicle.

[003] In the state of the art, there are known "hands-free" systems in which the onboard control system carries out the identification of the badge which is in its area of influence using radio frequency channels. If the badge is identified by its number, stored in a writable memory, the onboard control system then activates means for authorizing the control of the functions of the motor vehicle by the badge wearer.

[004] However, this state of the art encounters two problems that can be disadvantageous.

[005] According to a first problem, there is no simple solution to ensure that the badge is actually worn by a human carrier. This is particularly the case when the radiofrequency badge of the state of the art is forgotten inside the vehicle. This is also the case when the badge is worn by a first person, but a second person as a child manipulates without authorization a command interface that only the first person wearing the badge should be able to use. For the description of solutions to such problems, reference will be made in particular to document FR - A - 2.838.223.

[006] According to a second problem, contactless communications such as those on radiofrequency channels are subject to transmission hazards, as is the case when parasites or interference are generated on the chosen channel. There are technical solutions that reduce the risk of cutoff of the radiofrequency communication channel. Reference is made in particular to document FR-A-2.839.801.

[007] In another state of the art represented by US Pat. No. 4,591,854, it has been proposed to use a through-current data transmission technique. the body or TTS (Transmission Through Skin in English). A body object, such as a watch worn on the wrist, has a memory in which is written in advance an identifier code. The latter can be transmitted from the watch to a receiver in connection for example with a computer. The body of the user serves as a conductor for the current flow between these two entities.

[008] The transmission of the code entered in the watch is established only if the finger of the badge wearer comes into contact with a conductive plate of the receiver associated with the computer.

[009] Unfortunately, such a signal transmission technique traversing the body is not adaptable to a "hands-free" access system for the reason that, of course, it would require the establishment of a physical contact between the body. user and the possible embedded control system that would use it when, conversely, the system of access "hands-free" tends to avoid this contact.

[010] However, the inventor realized that such a current transmission through the body would ensure that the badge is worn by a person and that this guarantee would make it safer and more reliable. access to the vehicle and / or the control of other vehicle functions in connection with the use of a hands-free access system for a motor vehicle.

[011] Indeed, the present invention provides a simple solution and usable in many circumstances to solve the aforementioned problems. It relates to a system of access "hands-free" and / or control of functions of a motor vehicle of the type comprising at least one badge and a control system on board the motor vehicle connected to at least one control device access and / or function of the vehicle. According to the invention, such a system comprises means implementing a current transmission channel passing through the body for the exchange of data, in the form of a current, between the badge and the control system to ensure that the The initiator of the control of the functions of the motor vehicle is a user wearing the badge.

[012] According to another aspect of the invention, the means implementing a current transmission channel passing through the body comprise a TTS communication means on the vehicle comprising a conductive plate, arranged in a housing associated with at least one opening of the motor vehicle and / or a starter button of the motor vehicle, an electrode is connected to a receiving channel and a means for detecting an identification signal emitted by a conductive plate on the badge to detect the presence of the badge holder when a command or function of the vehicle is activated.

[013] According to another aspect of the invention, the system also comprises means for implementing a low frequency transmission channel intended for the activation of the badge in an area (Zone_l) near the motor vehicle or in a zone (Zone_2) of the passenger compartment of the motor vehicle which cooperates with the transmission channel TTS in order to detect the presence of the badge wearer when a command or function of the vehicle are activated.

[014] According to another aspect of the invention, the system also comprises means for implementing a high frequency transmission channel for identifying the badge, in order to detect the presence of the badge wearer when a command or a vehicle function are activated.

[015] According to another aspect of the invention, the system also comprises means for detecting an approach of an object with a device PSU (proximity sensor unit), associated with at least one opening of the motor vehicle and or a start button of the motor vehicle to activate the control system which cooperate with the current communication means passing through the body to detect the presence of the badge wearer when a command or function of the vehicle are activated.

[016] According to another aspect of the invention, the means for detecting an approach of an object comprise at least one capacitive sensor and / or one infrared sensor, for detecting an approach of an object with said device PSU in order to detect an intention of controlling the functions of the motor vehicle as an unlocking of the opening of said vehicle which cooperates with the current communication means passing through the body in order to detect the presence of the badge wearer when a command or a function of the vehicle are activated.

According to another aspect of the invention, the means for detecting an approach of an object comprise at least one capacitive and / or infrared sensor associated with the starter button of the motor vehicle for detecting an approach of an object. with said PSU device for detecting a starting command intention of the motor vehicle which cooperates with the current communication means traversing the body to detect the presence of the badge wearer when a command or function of the vehicle is activated.

[018] According to another aspect of the invention, the system comprises means for detecting a contact of an object with a PSU device for detecting an intention of controlling the functions of the motor vehicle as an automatic locking of the opening of the vehicle automotive, which cooperate with the current communication means through the body to detect the presence of the badge wearer when a command or function of the vehicle are activated.

[019] According to another aspect of the invention, the means implementing a current transmission channel passing through the body are means implementing a bidirectional transmission channel between the badge and the onboard control system to ensure that the initiator of the control of the functions of the vehicle automobile is an authorized user wearing the badge. [020] According to another aspect of the invention, the on-board control system cooperates with at least one radiofrequency field emission conductive electrode for activation of the badge by detection on the current communication pathway through the body of receipt of the badge, said conductive electrode being disposed in relation to the vehicle as on an opening of the vehicle, in particular on a device associated with a vehicle door and or a vehicle function control member as the starting member of the group Transmissions. [021] According to another aspect of the invention, the badge comprises a conductive plate for transmitting modulated signals for identifying the badge and the control system connected to the means using current flowing through the body. [022] According to another aspect of the invention, the badge comprises means for waking the badge coupled with a remote reception channel of a radiofrequency wave wakeup of the badge produced under the control of the onboard control system. [023] According to another aspect of the invention, the badge comprises and / or the on-board control system cooperates with a wave characteristic comparison means for distinguishing a current-type communication TTS contact through the body with a conductive electrode and a current communication TTS transmission passing through the remote body. The invention will be better understood, and other objects, features, details and advantages thereof will appear more clearly in the explanatory description which follows, with reference to the appended drawings in which: FIG. 1 illustrates an example of cutting the location areas of a badge for a hands-free system for controlling the functions of a motor vehicle; Figure 2 illustrates, schematically, an embodiment of the device according to the invention; FIG. 3 schematically illustrates the means implementing a current transmission channel passing through the body; FIG. 4 illustrates in flowchart form the operation of a hands-free system in accordance with the requirements of the invention; - Figure 5 schematically illustrates an alternative embodiment of a hands-free system according to the requirements of the invention; Figure 6 schematically illustrates a second embodiment of a hands-free system according to the requirements of the invention. [025] We will first describe a number of disadvantages and problems encountered in the operation of a "hands-free" access system according to the preamble of the main claim. [026] In another known embodiment, the "hands-free" access system may comprise means for detecting the approach of an object, particularly the hand of a user, with one of the handles arranged. on each opening of the motor vehicle or with the start button located at the driving position of the vehicle. In particular, such means comprise a first capacitive sensor which makes it possible to elaborate an electrical signal whose at least one parameter (amplitude or phase) evolves according to the distance that separates the capacitive sensor from an object on approach. The electrical signal from the capacitive sensor is intended on the one hand to activate the hands-free system and on the other hand to detect an intention to control a function. For example, the user's hand approach to the door handle is interpreted by the identification system as an approach of a user and as the expression of an intention to open the door. concerned opening of the motor vehicle.

[027] In this case, there are many situations in which the electrical signal of the capacitive sensor representative of an approach can be falsely triggered by a jet of water in an automatic car wash, the passage of a pedestrian , a tree leaf, because the hands-free system does not know how to distinguish false alarms.

[028] In another known embodiment, the hands-free system further comprises means for detecting a contact of an object, particularly the hand of a user, with one of the handles disposed on each opening of the vehicle automobile or the starter button of the motor vehicle. In particular, such means comprise a switch or a second capacitive sensor whose capacity varies in contact with an object with a handle of an opening or the start button. The second capacitive sensor is essentially intended for the detection of an automatic locking intention. For example, when the user touches a door handle, the capacitance value of the second capacitive sensor changes and becomes characteristic of a contact. The identification system interprets this capacity value change as an automatic locking intention when, for example, the driver has exited an interior control zone to the vehicle.

[029] As in the previous case, it is impossible to guarantee in this state of the art that the action which produces the activation of the electrical detection signal is caused by the habitual user who can give a real locking order.

[030] In another known embodiment, the on-board part of the hands-free system comprises means for transmitting an interrogation signal transmitted either at low frequency, typically 125 KHz, or at high frequency, typically 433 MHz. The response signal by the badge is transmitted at high frequency at 433 MHz.

[031] In the state of the art, before the execution of one of the aforementioned access functions to the vehicle or vehicle function control as the powertrain start, the identification system is activated when the first capacitive sensor detects the approach of an object.

[032] The identification system then transmits radio frequency signals to wake up or activate the badge. Indeed, the various means constituting the badge are not permanently activated to limit energy consumption.

[033] The badge then responds to the identification system in a radiofrequency signal intended to confirm its presence in an area close to the motor vehicle or in the passenger compartment, its identifier code and its activation (or alarm). The identification system then compares the received data with its own data in memory, in order to authorize or not the control of the functions of the motor vehicle.

[034] Next, the identification system interprets the radio frequency data received as the location of the badge and the detection of the approach of an object with a door handle or the start button to detect a function control intent. In the state of the art, in order to control a function of the motor vehicle, the hands-free system initially detects a command intention on the part of the user wearing the badge, such as unlocking the doors or of the boot, voluntary locking or starting of the motor vehicle.

[035] For example, the location of the badge near the motor vehicle and the detection of the approach of an object with the handle of the safe are interpreted by the identification system as an intention to unlock the trunk.

[036] Finally, the identification system then controls, if the identification code of the badge is confirmed, the necessary actuators implementing the function desired by the user as the unlocking of the doors.

[037] A disadvantage of this state of the art is that the radio frequency signals exchanged between the identification system and the badge can be disturbed by radiofrequency noise rendering the hands-free system inoperative.

[038] Another disadvantage of this state of the art is an unintentional unlocking of the opening of the motor vehicle by an unauthorized person. In particular, the badge wearer may be in an area close to the motor vehicle, in which case the badge will be identifiable. An unauthorized person, that is to say without the badge, can thus unlock the doors by actuating a handle of one of the doors of the motor vehicle.

[039] Another disadvantage of this state of the art is that the hands-free system can be easily hacked. Indeed, knowing the shape of the radio frequency signals exchanged between the badge and the identification system, it would be possible to produce the radio frequency signals necessary to unlock the opening of the motor vehicle and the starting of the motor vehicle. A poorly indi- tention could penetrate the motor vehicle and thus steal it.

[040] Another disadvantage of this state of the art is an involuntary unlocking in the presence of external disturbances. Indeed, the first capacitive sensor for detecting an approach is sensitive to external disturbances, in particular produced by water when it is raining or during an automatic washing, etc. In such a situation, if the wearer of the badge is in the vicinity of the motor vehicle, the hands-free system having identified the presence of the badge near the trunk can authorize the unlocking of the trunk. When the latter is motorized, it opens automatically. This situation is of course very delicate.

[041] Another disadvantage of this state of the art is an involuntary locking of the opening of the motor vehicle. This situation can occur when the badge is in an ambiguity zone, ie areas of overlap between the location zone in the passenger compartment and the location area outside the vehicle. The hands-free system may not be able to distinguish one of these areas and may therefore lock the vehicle although the badge is still present in the passenger compartment.

[042] Another disadvantage of this state of the art is an involuntary start of the motor vehicle. For example, the driver is not in the cockpit and the badge is in the cockpit. A passenger, like a child, can start the motor vehicle. Thus, as long as the badge is present in the passenger compartment, any unauthorized person can start the motor vehicle.

[043] The inventor realized that these drawbacks of the state of the art result either from the function control by an unauthorized person or from an external disturbance.

[044] The inventor realized that it would be very advantageous to integrate a device with the current hands-free systems which would make it possible to ensure that the initiator of the control of the functions is indeed an authorized person. is a user wearing the badge on him. However, the means used in the current hands-free systems, such as radio frequency means and the various capacitive sensors, do not allow the realization of such a system.

[045] In another state of the art, there have already been described devices using a transmission of current signals passing through the body TTS (acronym for Transmission Through Skin). Generally such devices are used to allow access to a room, such as a hotel room, or a safe by an authorized person carrying an electronic circuit generating the current flowing through the body. However, devices implementing such a transmission are permanently activated and consume a lot of energy.

[046] The inventor therefore had the idea not only of integrating a current transmission passing through the body to the current hands-free systems for a motor vehicle but also to activate the means implementing this transmission TTS only when the hands-free system must ensure that the badge is worn by an authorized person to limit the energy consumption. The "hands-free" access system of the invention therefore comprises activation means for waking the electronic circuits of the badge. [047] Figure 1 shows an embodiment of a "hands-free" access system implementing the invention. The "hands-free" access system therefore mainly comprises an on-board control system and at least one badge. The badge is worn by a driver who comes near the on-board control system aboard the vehicle N. If the access system is built on the basis of a radiofrequency system, as has already been mentioned more In the exemplary embodiment, the onboard control system is connected to at least three types of antennas: A first type of low frequency transmission antenna BF posted on a deck associated with each vehicle door; • A second type of low frequency antenna BF posted near the vehicle start - up device, at the driving position; • A third type of HF high frequency antenna placed on the roof or associated with the roof antenna of the vehicle.

[048] The "hands-free" access system of this embodiment of the invention essentially comprises: an on-board control system 6 on board the vehicle V; at least one badge 4 intended to be worn by an authorized user.

[049] The badge 4 of the invention is most often constituted by a small plate, like a credit card or a little thicker housing. The badge 4 comprises, in a first embodiment of the "hands-free" access system of the invention, only TTS communication means are disposed in the badge, using currents flowing through the badge holder body, and that will be described later.

[050] In other embodiments of the "hands-free" access system of the invention, the badge 4 also comprises RF radio frequency commumcation means which are intended to interact with the on-board control system 6 and which cooperate with the TTS communication means of the badge 4 as will be described later.

[051] The onboard control system 6 is connected by known means to specific devices which are of three types: - approach detection devices and / or remote remote control by example based on a high frequency antenna HF; - PSU devices related to the access functions to the passenger compartment of the vehicle and most often associated with an opening of the vehicle such as a door PI to P4 and a rear trunk C; - DEM devices linked to vehicle-specific functions such as the powertrain start function.

[052] For reasons of simplicity, there is shown a single PSU type unit attached to the door PI and connected by a 6-1 electrical connection to the control system 6 on board the vehicle V. However, preferably, each opening P2, P3, P4 and C have their own PSU device which is connected via a similar link 6-2, 6-3, 6-4 and 6-C to the control system 6.

[053] PSU-type peripherals comprise means by which the badge wearer can intervene on manual control interfaces such as a capacitive or infrared sensor or a switch to trigger a locking or unlocking of the openings. More generally, they comprise sensors capable of detecting an approach or an intention to activate a function of the vehicle.

[054] In a first embodiment which will be detailed below, the "hands-free" access system of the invention may comprise only PSU type devices associated with the opening of the vehicle V. Each device or PSU unit associated with an opening PI, P2, P3, P4 or C of the vehicle V also comprises means TTS not shown in Figure 1 which allow to establish a dialogue between the badge 4 and the onboard control system 6 on the only way TTS.

[055] In a second embodiment, in which badge 4 and embedded control system 6 comprise and / or cooperate with radio frequency means, the hands-free access system makes it possible to distinguish three types of zones in the vicinity of the radio. motor vehicle V: - A zone type Zone_l for which the badge holder will be located at a distance from the vehicle, that is to say that it will be determined as being in a phase of approach or removal of the motor vehicle N using the HF approach detection device; A zone type Zone 2 for which the badge holder will be located in the passenger compartment of the motor vehicle, particularly an area close to the driving position, particularly by a DEM type device; - A zone type ZoneZ3 particularly close to the doors PI to P4 and the trunk C by means of a device of type PSU.

[056] Note that each of the three types of zones have areas of overlap or ambiguity, particularly the zone represented in the drawing where Zone_l and Zone_2 zones overlap or overlap. Indeed, zone Zone2 not being not strictly defined by the passenger compartment of the motor vehicle, there may appear phenomena of overflow of said area.

[057] Zones Zone_l and Zone_2 are reserved for the exchange of radio frequency data between a badge 4 and a control system 6 on board the motor vehicle V. The radio frequency data exchange allows the functions of: activation of the badge 4; badge identification 4; location of the badge 4.

[058] Referring now to Figure 2 in which is shown an embodiment of the second embodiment of the invention in which cooperate radiofrequency means and means TTS implementing currents through the body of the carrier of the badge 4 are detailed. To achieve a system according to the first form of the invention, the skilled person can remove most of the means used in radio frequency communications.

[059] To implement a radio frequency channel, the control system 6 comprises means 22, 24, 26 for transmitting low-frequency signals, particularly a low-frequency transmission antenna 22 which transmits in the Zone_l zone, a low-frequency transmission antenna 24 which transmits in the Zone_2 zone and a processing unit 26 low-frequency signals to be transmitted.

[060] The control system 6 further comprises means 28, 30 for receiving high frequency signals, particularly a high frequency reception antenna 30 and a processing unit 28 of the received high frequency signals.

[061] The badge 4 comprises means 8, 12 for receiving low-frequency signals emitted by the control system 6, particularly a low-frequency antenna 8 and a processing unit 12 of the low-frequency signals emitted by the control system. control 6.

[062] The badge 4 comprises means 10, 14 for transmitting high-frequency signals to the control system 6, particularly a high-frequency antenna 10 and a processing unit 14 of the high-frequency signals to be transmitted.

[063] Once the control system 6 activated by means indicated later in the description, the low-frequency antennas 22 and 24 periodically emit low-frequency signals respectively in Zones Zone_l and Zone_2.

[064] The low-frequency signals are emitted by an antenna BF associated with the vehicle and powered by a suitable modulator of the control system 6. They carry data comprising a control system identifier code 6, if any, an identifier code badge 4 and the useful part of the transmission, here an activation data (or wake up) of the badge 4.

[065] The badge 4 thus comprises that there is known a source of electrical energy (no shown) and an electronic processor 16. The processor 16 of the badge 4 manages the communications of both the TTS means and the RF means when they are implemented. In order to limit its power consumption, the processor places the badge 4 in a so-called "standby" mode where it is only able to receive the low-frequency signals emitted by the control system 6. The "sleep" mode is activated when the badge 4 is no longer in the zones Zone_l and Zone_2 or when the user no longer manually controls the badge 4, particularly when it includes a remote control user interface of the vehicle functions.

[066] After reception of the low-frequency signals, the processor or processing unit 16 of the badge 4 compares the identifier code of the control system 6 with a reference value contained in a memory of the badge 4. If the control system 6 is recognized by the processing unit 16, the badge 4 transmits a high-frequency acknowledgment signal to the control system 6 intended to warn it of its activation. The high-frequency acknowledgment signal carries, in particular, data comprising an identifier code of the badge 4, where appropriate the identification code of the control system 6 and the message itself, namely the acknowledgment (or confirmation) of the activation. badge 4.

[067] The badge 4 is thus activated and the embedded control system 6 has identified. In order to keep the badge 4 in an activated state, the badge 4 is periodically located by the RF means associated with the onboard control system 6 to ensure that it is always in one of the zones Zone_l to Zone_3 for which the activation of the badge 4 is of interest, particularly for controlling the functions of the motor vehicle.

[068] Thus, the control system 6 periodically transmits low-frequency maintenance signals to the badge 4 for interrogating the badge 4 to ensure its presence in one of the zones.

[069] The non-reception of a high-frequency presence confirmation signal, beyond a predetermined time interval, is interpreted by the control system 6 as an output of the zone zone1 and zone_2 zone badge. The badge 4 is thus deactivated.

[070] The location of the badge 4 thus allows the badge 4 to be maintained in an activated state and to improve the function control intent detection.

[071] Figure 2 schematically illustrates an embodiment of an access system 2 comprising a badge 4, a control system 6 and a device PSU 50.

[072] Particularly, the device PSU 50 is associated with a door or trunk handle or the starter button of the motor vehicle located in the driving position.

[073] Thus, according to the embodiment described in FIG. 1, the access system 2 has a PSU device 50 for each door PI, P2, P3, P4, for the safe C and for the start button DEM (see Figure 1).

[074] The PSU device 50 comprises a detection means, such as a conductive plate 48, a modulated identification signal transmitted by the badge 4 via the current transmission channel passing through the body.

[075] The PSU device 50 includes means such as a first proximity capacitive sensor 44 for detecting an approach of an object, particularly the hand of a user, with said PSU device 50. The capacity value of the capacitive sensor 44 proximity is variable and varies depending on the distance between the object of the PSU 50 device.

[076] The PSU device 50 includes means such as a second contact capacitive sensor 46 for detecting a contact of an object, particularly the hand of a user, with said PSU device 50. The capacitance value of the capacitive sensor 46 contact is variable and takes different values, one in case of contact and another in case of non-contact.

[077] The badge 4 comprises: means (8, 12) for receiving low-frequency signals emitted by the control system 6 of the type a low-frequency receiving antenna 8 and a low-frequency signal processing unit 12 ; means (10, 14) for transmitting high-frequency signals to the control system 6 of the type a high-frequency transmission antenna 10 and a high-frequency signal processing unit 14; a means 20, such as a conductive plate, intended for the implementation of proximity and contact detection with the PSU device 50. The conductive plate generates a modification of the capacitance value of the capacitive sensors when the distance which separates from the device PSU 50 decreases; a TTS-Badge processing unit 18 for modulated identification signals to be transmitted to the control system 6 via a current-passing channel passing through the body, said unit comprising a conductive plate (not shown) and modulation means ( not shown); a processor or control and control unit 16 intended to control and control the badge 4. [078] The control system 6 comprises: - means (28, 30) for receiving high-frequency signals transmitted by the badge 4 of the type a high frequency reception antenna 28 and a high frequency signal processing unit 30; means (22,24,26) for transmitting low-frequency signals to the badge 4 of the type of a low-frequency transmission antenna 24 in the passenger compartment, a low-frequency transmission antenna 22 in an outer zone near the motor vehicle and a low-frequency signal processing unit 26; a detection unit 34 intended for the implementation of the proximity and contact detection with the PSU device 50. According to the values of the measured capacitances of the capacitive sensors 44 and 46, the detection unit 34 is able to determine whether an object is near or in contact with the PSU 50 device; a TTS-access processing unit 36 of the modulated signals transmitted by the badge 4 via the current transmission channel passing through the body, said unit comprising demodulation means (not shown); a control and control unit 32 intended to control and control the control system 6; a microcontroller 38 for controlling actuators 40 means for unlocking the various openings of the vehicle, means for locking the doors of the vehicle and means for starting the vehicle.

[079] In one embodiment, the low-frequency antennas 22 and 24 are replaced by low-frequency antennas, each associated with a PSU device 50. Thus, the low-frequency antennas associated with the opening PI, P2, P3 , P4, C can activate the badge 4 near the motor vehicle, particularly to an opening, and the low-frequency antenna associated with the start button to activate the badge 4 in the passenger compartment of the motor vehicle.

[080] We will now explain briefly, with reference to Figure 3, the constitution of the current communication pathway through the body. A badge 4 according to the invention comprises the already known resources for establishing the two radio frequency communication channels. The badge 4 of the invention then comprises at least one electrode preferably in the form of a conductive plate 58 intended to come into contact with a part of the body of the person wearing the badge 4, for example when the badge is held at the door. hand or when it is placed in a pocket of a garment worn by the badge wearer. The conductive plate 58 is inside the badge 4 connected to the output of a modulation circuit 54, 56 which continuously produces a modulation signal established on the basis of a local carrier, for example a sinusoidal carrier of a frequency between 5 and 100 kHz and on the basis of identification codes read on a MEM memory register integrated badge 4. Of course, the present invention does not require that the badge 4 is constituted in a single object. It can comprise several separate objects, for example if the part of badge 4 implementing the current communication resource through the body is integrated in another object in contact with the body. [081] When the badge wearer puts his hand or finger on an electrode or conductive plate 48 associated with the device PSU 50, a current flowing through the body is established between the conductive plate 58 of the badge 4 and the conductive plate 48 associated with the PSU device 50. This current flowing through the body carries the modulation signal generated by the badge 4 which is then received on a TTS-access processing unit 36, integrated into the control system 6 on board the vehicle. Such a TTS-access processing unit 36 comprises a detection circuit 62 whose input is connected to the conductive plate 60 associated with the PSU device 50 and the output of which is connected to a demodulation circuit 64 which extracts the codeword d identification which is then provided to a first input of a comparator 66 of code words of which another input is connected to a memory 11 unwinding a table of authorized codes, particularly the different codes identifying authorized badges. If the comparison is positive, the processing unit TTS-access 36 to the control and control unit 32 provides a signal identifying the badge 4 detected and identifying the zone, namely Zone Zone1 or zone Zone2, in which badge holder 4 has been detected as physically touching a part of the vehicle. [082] Figure 4 illustrates in flowchart form the operation of a hands-free system 2 according to the requirements of the invention. [083] In a first step, the hands-free system 2 is activated. The activation of the hands-free system 2 comprises: a step of waking up the control system 6 by detecting an approach (or the proximity) of an object , particularly the hand of a user, with one of the housings 50. The proximity detection with the device PSU 50 is performed when the value of the capacitance of the first proximity capacitive sensor 44 becomes characteristic of a proximity with said peripheral PSU 50. The detection unit 34 compares the value of the measured capacitance with a reference threshold. When this value becomes greater than the threshold, the detection unit 34 interprets it as a proximity detection and sends a signal representative of a proximity detection to the control and control unit 32 which activates the means (28, 30) implementing the radiofrequency trans ission. Of course, the threshold is defined according to the sensitivity that one wishes to grant to the capacitive sensor. a step of waking up the badge 4 by transmitting low-frequency signals to the badge 4 via the low-frequency antenna 22 or the low-frequency antenna 24, said signals being of the type comprising data comprising the identifier code of the badge 4 the identification code of the control system 6 and the object of the signal namely the awakening (or activation) of the badge 4; a step of acknowledgment (confirmation) of the activation of the badge 4 which transmits to the control system 6 via the high-frequency antenna 10 a high-frequency signal comprising in particular data of the type identifying code of the badge 4 intended to be recognized by the control system 6.

[084] Of course, if the control system 6 does not recognize the identity of the badge 4, the control system 6 prohibits any function control of the motor vehicle.

[085] The control system 6 also maintains the badge 4 in an activated state by transmitting to the badge 4 low-frequency maintenance signals to which the badge 4 responds by emitting high-frequency signals confirming its presence in the Zone_l zone or the Zone_2 zone.

[086] Thus, this first step serves not only the activation of the hands-free system 2, but also the identification of the badge 4 and the maintenance of the badge 4 in an activated state by monitoring the location of the badge 4.

[087] In a second step, the hands-free system 2 detects an intention to control a function of the motor vehicle such as the unlocking of the doors, the unlocking of the trunk, the voluntary locking of the opening of the vehicle and the starting of the vehicle.

[088] In particular, the detection unit 34 intended for the implementation of proximity and contact detection with a PSU device 50 comprises means for detecting which of the proximity capacitive sensors 44 is responsible for a detection of an approach of an object, particularly the hand of a user, towards one of the housings 50.

[089] Thus, when the detection unit 34 detects that a proximity capacitive sensor 44, disposed in one of the housings 50 of the doors P1, P2, P3 or P4, is responsible for the detection, it transmits to the control and control unit 32 a signal representative of an intention to unlock the doors of the motor vehicle.

[090] When the detection unit 34 detects that the capacitive sensor 44, disposed in the PSU device 50 of the box C, is responsible for the detection, it transmits to the control and control unit 32 a signal representative of an intention to unlock the trunk of the motor vehicle.

[091] When the detection unit 34 detects that a capacitive proximity sensor 44, disposed in the PSU device 50 of the start button, is responsible for the detection, it transmits to the control and control unit 32 a signal representative of an intention to start the motor vehicle.

[092] In order to detect an automatic locking intention, the hands-free system 2 comprises a means (not shown) for detecting the opening and closing of a door-type motor vehicle door and means (not shown). to detect the passage of the bearer of the badge 4 from zone Zone 2 to zone Zone 1 by to detect the exit of the carrier of the badge 4 of the passenger compartment. Thus, the simultaneous detection of the opening and closing of an opening and the passage of the badge wearer from one zone to another is intended to be interpreted as an intention of automatic locking. In addition, to confirm the intention of automatic locking, the control system 6 detects a contact of an object, particularly the hand of the user, with the PSU device 50 of one of the doors PI, P2, P3, P4 via the second capacitive contact sensor 46. The detection unit 34 compares the value of the capacitance of the capacitive touch sensor 46 with a reference value characteristic of a contact.

[093] If the contact of an object with the PSU device 50 is not detected, the control system 6 abandons the automatic lock. The location of the badge 4 further allows to invalidate or confirm the intention of a function command.

[094] In a third step, the control system 6 activates the means 18, 48, 36 implementing the current transmission channel passing through the body to ensure that the initiator of the vehicle function control is the holder of the badge 4, ie an authorized person.

[095] Advantageously, when an approach of an object with the PSU device 50 is detected and an error has occurred during the exchange of the radio frequency signals, such as the low-frequency signals emitted by the control system 6 and / or the high-frequency signals emitted by the badge 4 during the first step, the control system 6 automatically activates the means 18, 48, 36 implementing the current transmission through the body. Radiofrequency noise is generally responsible for an error in the exchange of radio frequency data for the location and / or identification of the badge 4.

[096] The current transmission through the body is established only if the conductive plate of the badge 4 and the conductive plate of the control system 6 are simultaneously in contact with a body part of the user carrying the badge.

[097] The purpose of this exchange is the identification of the badge 4 by the control system 6. The modulated identification signal issued by the badge 4 and includes data comprising the identifier code badge 4, the identifier code of the control system 6 and the object of the signals namely the identification.

[098] The control system 6 compares the identifier code of the badge 4 with a reference value contained in a memory to ensure that the identifier code received corresponds to a known code and therefore to ensure that the initiator function control is the holder of the badge 4, ie an authorized person.

[099] An interruption in the transmission and the control system 6 prohibits the control of the vehicle functions until a new attempt by the user. [100] Of course, if the identifier code of the badge 4 is not recognized by the control system 6, the control system 6 prohibits the control of the functions of the vehicle.

[101] In a fourth step, the control system 6 controls the relevant function of the motor vehicle. In particular, the control and control unit 32 transmits to the microcontroller 38 a signal representative of the detected function control. The microcontroller 38 then controls the actuators 40 adapted either for locking or unlocking the doors, or for unlocking the trunk or for starting the vehicle.

[102] Advantageously, the radiofrequency signals exchanged between the badge 4 and the control system 6 are encrypted in order to reinforce protection against piracy.

[103] Two embodiments of a hands-free system will now be described which use a current transmission channel passing through the body to ensure that the initiator of the control of the functions of the motor vehicle is an authorized person.

[104] In a first variant embodiment, the invention proposes a hands-free system 70, illustrated in FIG. 5, identical to that previously described, with the exception that it does not include the means intended for the implementation of FIG. a high-frequency transmission channel between a badge 72 and a control system 74.

[105] Therefore, the exchange of radiofrequency signals between the badge 72 and the control system 74 no longer functions as the identification of the badge 72 and the maintenance (or maintenance) of the badge 72 in an activated state. Particularly, the radiofrequency signals emitted by the control system 74 have the function of only waking (or activating) the badge 72 when the wearer of the badge enters one of the zones Zone_l or Zone_2.

[106] Thus, only the current transmission means TTS through the body allow identification of the badge 72, in addition to their main function.

[107] The hands-free system further comprises a box 102-106 identical to the device PSU 50 described in Figure 2.

[108] The housing 102-106 thus comprises: a first capacitive proximity sensor 102; a second capacitive contact sensor 104; a detection conductive plate 106.

[109] The badge 72 comprises: - means (76, 78) for receiving low-frequency signals emitted by the control system 74 of the type of a low-frequency receiving antenna 78 and a low-frequency signal processing unit 76; a means 82, such as a conductive plate, intended for the implementation of proximity detection and of contact with the housing 106. The conductive plate causes a change in the capacitance value of the capacitive sensors when the distance separating it from the housing 106 decreases; a TTS-badge processing unit 80 of modulated signals to be transmitted to the control system 74 via a current transmission channel passing through the body, said unit comprising a conductive plate (not shown) and modulation means (not shown); a control and control unit 84 intended to control and control the badge 72.

[110] The control system 74 comprises: means (86,88,90) for transmitting low-frequency signals to the badge 72 of the type a low-frequency transmission antenna 86 in the passenger compartment, an antenna of low frequency transmission 88 in an outer area near the motor vehicle and a low frequency signal processing unit 90; a detection unit 92 intended to implement proximity detection and contact with the housing 106. According to the values of the measured capacitances of the capacitive sensors 102 and 104, the detection unit 92 is able to determine whether a object is near or in contact with the housing 106; a TTS-access processing unit 94 of the modulated identification signals transmitted by the badge 72 via the current transmission channel passing through the body, said unit comprising demodulation means (not shown); a control and control unit 96 of the control system 74; a microcontroller 98 for controlling actuators 100 of the type of means for unlocking the various openings of the vehicle, means for locking the opening of the vehicle and means for starting the vehicle.

[111] This embodiment has an economic advantage since means have been removed.

[112] In a second variant embodiment, the inventor proposes a hands-free system 110, illustrated in FIG. 6, identical to the previous ones, with the difference that it no longer comprises means implementing the radio frequency transmission. ie low-frequency transmission and high-frequency transmission.

[113] The hands-free system 110 always includes a badge 112, a control system 114 and a PSU device 116.

[114] An essential feature of such a hands-free system 110 is that the current transmission through the body is bi-directional here to awaken (or activate) the badge 112 and secondly to implement identification of 112 and the control system 114. [115] The PSU device 116 is identical to the device PSU 50 described in Figure 2 and has the same characteristics. [116] The PSU device 116 thus comprises: a first proximity capacitive sensor 118; a second capacitive contact sensor 120; a conductive detection plate 122. [117] The badge 112 comprises: a means 124, such as a conductive plate, intended for the implementation of proximity and contact detection with the PSU device 116. The conductive plate generates a changing the capacitance value of the capacitive sensors when the distance separating it from the housing 106 decreases; a TTS-badge processing unit 126 of the signals exchanged via the current transmission channel passing through the body, said unit comprising a receiving transmission conductive plate 128, demodulation modulation means 130; a unit 132 for controlling and controlling the badge 112. [118] The control system 114 comprises: a detection unit 134 intended for the implementation of the proximity and contact detection of an object with the housing 116; a TTS-access processing unit 136 of the signals exchanged between the badge 112 and the control system 114 via the current transmission channel passing through the body, said unit comprising means 138 for demodulation and modulation, and means 140 for comparing wave characteristics of modulated signals; a control and control unit 142 of the control system 114; a microcontroller 144 for controlling actuators 146 of the type of means for unlocking the different openings of the vehicle, means for locking the doors of the vehicle and means for starting the vehicle.

[119] In order to limit the energy consumption of the hands-free system 110, the hands-free system 110 is by default in a so-called "sleep" mode. In particular, the means 122, 136, intended for implementing the current transmission channel passing through the body, are deactivated.

[120] Thus, approaching a body part of a user to a PSU device 116, the PSU system 118, 124, 134 detects, through the capacitive proximity sensor 118, the approach of said body part.

[121] The PSU system 118, 124, 134 emits a signal representative of a detection of proximity to the control and control unit 142 which activates the means 122, 136 implementing the current transmission channel passing through the body.

[122] In addition, the PSU system 118, 124, 134, thanks to the proximity detection as already described, detects a function control intention of the motor vehicle associated with the housing 116 for which the PSU system 118, 124, 134 has detected an approach.

[123] To wake the badge 112, it has been found that, even without the person wearing the badge 112 is in contact with the housing 116, the conductive plate 122 of the control system 114 itself radiates a radio frequency field on the basis of a modulated identification signal. The conductive plate 122 then acts as a radiofrequency transmitting antenna. The invention is based on the use of this radio frequency field to activate the badge 112. Thus, when the control system 114 is activated, the conductive plate 122 emits a radiofrequency field on the basis of a modulated identification signal comprising data comprising the identifier code of the badge 112 and the identification code of the control system 114.

[124] The conductive plate 128 of the badge 112 receives the radio frequency field which activates the badge 112, provided that the identification code of the control system 114 is recognized.

[125] Only, the conductive plate 128 of the badge 112 also radiates and the conductive conductive plate 122 necessarily receives this radiofrequency wave.

[126] The TTS-access processing unit 136 can thus demodulate the modulated remote identification signal and therefore the identifier code of the badge 112, which of course is not desirable in accordance with the requirements of the invention if we want to ensure that the initiator of the function control is indeed the badge wearer.

[127] Thus, the hands-free system 110 includes means for distinguishing an identification situation of the badge holder depending on whether or not the wearer touches the conductive detection plate of the control system.

[128] The TTS-access processing unit 136 includes a wave signal comparator, particularly a phase comparator.

[129] The TTS-access processing unit 136 furthermore comprises a high-frequency antenna for receiving high-frequency signals transmitted by the badge because of the radio-frequency radiations of the conductive plate 128.

[130] Thus, in the absence of contact of a body part of the badge wearer with the housing, the receiving part can demodulate a "remote" identification code. Such a system is thus able to implement a "contact" detection mode and a "remote" detection mode.

[131] Thus, the invention is based here on the distinction between these two detection modes. However, the two detection modes mentioned above are distinguished by a difference in character. wave characteristic.

[132] Indeed, the radiation modulation signal is 180 ° out of phase with the contact modulation signal. Thus, at a time t, the instantaneous amplitudes of the modulation signals are in phase opposition.

[133] The phases of the recovered signals are therefore compared using the wave characteristic comparator 140 as a phase comparator. Following this comparison, the TTS-access processing unit 136 evaluates whether the detection mode of the badge wearer is a "contact" detection mode or a "remote" detection mode of the conductive plate 122 according to whether the two signals are in phase (case of non-contact) or in phase opposition (case of contact). Of course, other phase laws or other wave characteristics that the phase are exploited according to the invention.

[134] The control system 114 thus takes into account the identifier code of the badge 112 only if the receiving part detects a real contact between a body part of the badge wearer and the conductive plate 122 of the receiving part.

[135] As long as the current transmission through the body is not established, that is to say when the body part of the user is not simultaneously in contact with the badge 112 and the housing 116, the control 114 prohibits any function command.

[136] Once the user, carrying the badge, puts his hand on the housing, the processing unit 136 transmits to the badge 112 a modulated identification signal comprising a badge identifier code 112, a code identifier of the control system 114 and the signal object as the identification of the badge.

The processing unit 126 of the badge demodulates, thanks to the demodulation means 130, the received identification modulated signal and then transmits the different identifier codes to the control and control unit 132 of the badge.

[138] The control and control unit 132 compares the identifier codes of the badge and the control system respectively to a first and second reference value.

[139] If the identifier codes are exact, that is to say recognized, the processing unit 126 emits a modulated signal (via the modulation unit) intended to confirm the identification of the control system 114, the activation the badge 112 and the location of the badge 112. The emitted modulated signal includes in particular the identifier codes of the badge 112 and the control system 114.

[140] The processing unit TTS-access 136 detects, thanks to the conductive plate 122 of detection, the modulated signal and in the same way as previously compares, after demodulation, the identifier codes to reference values. If the identification codes prove to be correct, the control system 114 authorizes the control of functions of the motor vehicle. Specifically, the control and control unit 142 transmits to the microcontroller 144 a signal representative of the detected function control. The microcontroller 144 then controls the actuators 146 adapted to either locking or unlocking the doors, or unlocking the trunk or starting the vehicle.

Claims

Claims “Hands-free” access and / or function control system of a motor vehicle of the type comprising at least one badge (4) and a control system (6) on board the motor vehicle connected to at least one access control and / or vehicle function peripheral (PSU, BF, RF, DEM), characterized in that it includes means (TTS) implementing a transmission channel through current the body intended for the exchange of data, in the form of current, between the badge (4) and the control system (6) to ensure that the initiator of the control of the functions of the motor vehicle is a user wearing the badge (4). [002] System according to claim 1, characterized in that the means (18, 48, 36) implementing a transmission channel by current passing through the body comprise means (48) of TTS communication on the vehicle comprising a conductive electrode (60), disposed in a housing (50) associated with at least one opening of the motor vehicle and / or with a starting button of the motor vehicle, of which an electrode is connected to a reception channel (62) then to a means ( 64, 66) for detecting an identification signal emitted by a conductive plate (58) on the badge (4) in order to detect the presence of the bearer of the badge (4) when a command or a function of the vehicle are activated. [003] System according to claim 2, characterized in that it also comprises means (8, 12, 22, 24, 26) for implementing a low-frequency transmission channel intended for activation of the badge (4 ) in a zone (Zone_l) near the motor vehicle or in a zone (Zone_2) of the passenger compartment of the motor vehicle which cooperates with the TTS transmission channel in order to detect the presence of the holder of the badge (4) when an order or a vehicle function is activated. [004] System according to any one of claims 2 or 3, characterized in that it also comprises means (10, 14, 28, 30) for implementing a high-frequency transmission channel intended for identification of the badge (4), in order to detect the presence of the holder of the badge (4) when a command or a function of the vehicle is activated. [005] System according to any one of claims 2 to 4, characterized in that it also comprises means (20, 34, 44) for detecting an approach of an object with a PSU device (50), associated with at least one opening of the motor vehicle and / or a motor vehicle start button to activate the control system (6) which cooperate with the means (TTS) in order to detect the presence of the badge holder (4) when '' a command or function of the vehicle are activated. [006] System according to claim 5, characterized in that the means (20, 34, 44) for detecting an approach to an object comprise at least one sensor such as a captive sensor or an infrared sensor capable of detecting the approach or the intention to activate the function (44), to detect an approach of an object with said peripheral PSU (50) in order to detect an intention to control functions of the motor vehicle such as unlocking the doors (PI - P4 , C) of said vehicle which cooperates with the means (TTS) in order to detect the presence of the badge holder (4) when a command or a function of the vehicle are activated. [007] System according to claim 5, characterized in that the means (20, 34, 44) for detecting an approach to an object comprise at least one approach sensor (44) associated with the vehicle start button motor vehicle to detect an approach of an object with said peripheral PSU (50) to detect an intention to control the start of the motor vehicle which cooperates with the means (TTS) in order to detect the presence of the holder of the badge (4) when a vehicle control or function is activated. [008] System according to any one of claims 2 to 4, characterized in that it comprises means (20, 34, 46) for detecting contact of an object with a PSU device (50) to detect an intention to control functions of the motor vehicle such as an automatic locking of the doors of the motor vehicle, which cooperate with the means (TTS) in order to detect the presence of the holder of the badge (4) when a control or a function of the vehicle are activated . [009] System according to any one of the preceding claims, characterized in that the means (TTS) implementing a current transmission channel passing through the body are means (122, 126, 136) implementing a transmission channel bidirectional transmission between the badge (4; 112) and the on-board control system (6; 114) to ensure that the initiator of the control of the motor vehicle functions is an authorized user wearing the badge (4). [010] System according to claim 9, characterized in that the on-board control system (6; 114) cooperates with at least one conductive electrode (122) for emitting radiofrequency fields intended for activating the badge (112) by detection on the reception TTS channel (128) of the badge (4; 112), said conductive plate (122) being arranged in relation to the vehicle as on an opening of the vehicle, in particular on a peripheral (PSU). [011] System according to any one of claims 9 or 10, characterized in that the badge (4; 112) comprises a conductive plate (128) for emission and reception of modulated identification signals of the badge (112) and of the control system (114) connected to the means (TTS) implementing current passing through the body. [012] System according to one of claims 10 or 11, characterized in that the badge (4; 112) comprises means for awakening the badge coupled with a remote reception channel of a radio frequency wave for awakening the badge produced under the control of the on-board control system (6; 122). [013] System according to claim 12, characterized in that the badge (4; 122) comprises and / or the on-board control system (6; 114) cooperates with a means for comparing wave characteristics to distinguish a TTS type contact with a conductive plate (122) and a remote TTS transmission.