Method for activating a vehicle function and associated activation device

Abstract

The invention relates to a method for activating a vehicle function, by an activation device (D), from a "hands-free" access apparatus (SD) equipped with an accelerometer (ACC), the activation of the function being triggered by a detection of the presence of the apparatus (SD) in a predetermined zone (Z1) and depending on a result of authentication of the apparatus (SD), the device comprising at least one transceiver able to communicate with the apparatus in ultra-wideband (ULB), and in ultra-high frequency (BLE), the method comprising the following steps: a) detecting, by ultra-high frequency, a presence of the access apparatus in the predetermined zone; b) authenticating the apparatus by ultra-high frequency; c) obtaining measurements of acceleration of the access apparatus; and i) if the measurements are representative of a movement of the access apparatus greater than a threshold from a last fixed position, then stopping the ultra-high frequency communication and triggering the ultra-wideband communication, and activating the vehicle function; ii) otherwise, if the measurements are representative of a static state of the access apparatus, from a last fixed position, then maintaining the ultra-high frequency communication.

Description

DESCRIPTION TITLE: METHOD FOR ACTIVATING A VEHICLE FUNCTION AND ASSOCIATED ACTIVATION DEVICE [Technical field]

[0001] The invention relates to a method for activating a function of a motor vehicle and an associated activation device. The invention applies particularly but in no way limitingly to the function of hands-free access to a motor vehicle using a smart mobile phone, the function being for example the function of locking and unlocking the openings of a motor vehicle. [State of the prior art]

[0002] In a motor vehicle, it is known to use vehicle function activation devices capable of detecting the presence of a hand or foot of a user of the vehicle and thus enabling the locking or unlocking of all or part of the vehicle's openings, for example the doors or the trunk. For example, detecting the presence of a user's hand on or in front of a door handle coupled with the recognition of an identifier of a "hands-free" access device worn by this user, enables the locking and unlocking of these openings.

[0003] A so-called "hands-free" access system for a motor vehicle allows an authorized user to lock and / or unlock the openings of his vehicle without having to physically press buttons on a key. To do this, the vehicle identifies portable equipment such as a badge or remote control worn or even a key, by the user and if the badge or remote control or the key is located in a predetermined area around the vehicle or in the vehicle and is identified as belonging to the vehicle, then the vehicle automatically locks / unlocks its openings according to the user's intention, without the user having to physically handle a key.

[0004] To do this, when the user approaches the vehicle, communication is established over a wireless communication link between the “hands-free” access equipment, for example an electronic badge or a smart mobile phone, and the vehicle function activation device in order to authenticate said access equipment using its identifier.

[0005] For this purpose, the activation device comprises at least one radiofrequency antenna allowing the reception of the identifier sent by the “hands-free” access equipment. The The activation device is connected to an electronic control unit of the vehicle (“ECU”: English abbreviation for “Electronic Control Unit”) to which it transmits the identifier.

[0006] Depending on the location of the portable equipment identified by the vehicle, in said location zones certain actions specific to said location zones are automatically carried out, unlocking / locking or prior switching on of the passenger compartment lighting (also called “welcome lighting” in English).

[0007] Nowadays, however, it is increasingly common to use a mobile phone to perform authentication functions, which makes it possible to avoid using a dedicated electronic badge and thus limit the number of devices. Most mobile phones do not have RF or LF communication means. It therefore becomes necessary to adapt the "hands-free" access and / or starting system to a vehicle so that it can also work with a mobile phone equipped with other communication standards, such as, for example, "Ultra Wide Band" in English or Ultra Large Band, ULB in French, or by "Bluetooth Low Energy" ® in English or Bluetooth à basse consommation, or by WIFI communication ("Wireless Fidelity" in English or wireless fidelity) and no longer only via radio waves and low frequencies (RF, LF).Ultra wideband (UWB) is a radio modulation technique based on the transmission of very short pulses, often less than a nanosecond. Thus, bandwidth can reach very high values.

[0008] Bluetooth communication is a communication at a frequency of around 2.4 GHz.

[0009] The method for activating a vehicle function using a mobile phone then consists of: a. Detecting by Bluetooth communication the distant presence of the access equipment, i.e. around 100 m around the vehicle, and establishing a first communication link by Bluetooth between the access equipment and the activation device, b. Recognizing the identifier received by Bluetooth by the vehicle. c. Then, detecting by UWB, the close presence of the access equipment, i.e. within a radius of a few meters, for example around 10 m to 15 m around the vehicle, and precisely locating by UWB the position of said equipment in order to activate security vehicle functions such as unlocking, locking, etc.

[0010] However, this method has a major drawback when the vehicle is parked within a radius of 10 m to 15 m around the access equipment and the user does not wish to activate a vehicle function. For example, when the vehicle is parked in a garage and the access equipment is placed in a receptacle located in the house adjoining the garage. In this case, all the steps of the above method will be carried out, and the vehicle will be unlocked, then locked, then unlocked, and so on in a cyclical manner without the user wishing to activate these functions.

[0011] The scenario is even more critical when the vehicle is parked in front of the house where the portable equipment is permanently located within the UWB communication range. The vehicle is then unlocked at recurring frequency and can therefore be easily stolen.

[0012] Another significant disadvantage of this prior art method is that the vehicle battery and the access equipment battery will drain very quickly, as they are over-used by these recurring requests and these cyclical locking and unlocking actions. This reduces their lifespan.

[0013] The invention therefore proposes a method for activating a vehicle function and an associated activation device overcoming the drawbacks of the prior art and thus eliminating the risk of theft of the vehicle and extending the life of the vehicle batteries and the portable equipment. [Statement of the invention]

[0014] The invention relates to a method for activating a vehicle function, by an activation device, from a "hands-free" access equipment capable of being worn by a user, the access equipment being provided with an accelerometer, the activation of the function being triggered by a detection of the presence of the equipment in a predetermined area around the vehicle, and as a function of an authentication result of the equipment, the activation device comprising at least one transceiver capable of communicating with said equipment in ultra wide band, and in ultra high frequency, the method being remarkable in that it comprises the following steps: a. Detection by ultra high frequency communication, of a presence of the access equipment in a predetermined area around the vehicle, b. Authentication of said equipment by ultra high frequency communication, c. Acceleration measurements of the access equipment, and d. If said measurements are representative of a movement of the access equipment greater than a threshold from a last fixed position, then stopping of the ultra high frequency communication and triggering of the ultra wide band communication, and activation of the vehicle function, e. Otherwise, if said measurements are representative of a static state of the access equipment, from a last fixed position then maintaining of the ultra high frequency communication.

[0015] In an improvement of the activation method according to the invention, if said measurements are representative of a movement of the access equipment between a minimum movement and the threshold, then the ultra high frequency communication is stopped and the ultra wide band communication is triggered at a reduced transmission frequency and the vehicle function is activated.

[0016] Preferably, said acceleration measurements are transmitted by the access equipment to the activation device.

[0017] The invention also relates to a device for activating a function of a motor vehicle intended to be embedded in the vehicle, the activation of the function being triggered by a detection of the presence of a portable “hands-free” access device, capable of being worn by a user, in a predetermined area around the vehicle and as a function of a result of authentication of said equipment by the vehicle, the activation device comprising at least one Ultra Wide Band and ultra high frequency transmission and reception transmitter capable of communicating with said equipment in ultra wide band and ultra high frequency, the device being remarkable in that it further comprises: a. means for detecting by ultra high frequency a presence of the access equipment in a predetermined area, b. means for authenticating by ultra high frequency said equipment, c. Means for receiving acceleration values ​​in ultra high frequency from said equipment, d. Means for stopping or maintaining communication in ultra high frequency and for triggering communication in ultra wide band as a function of said acceleration values ​​from a last fixed position.

[0018] In the improvement mode, the device further comprises means for triggering ultra-wideband communication with a reduced frequency as a function of said acceleration values ​​from a last fixed position.

[0019] The invention also applies to any computer program product comprising program code instructions for executing the steps of the method according to any of the characteristics listed above when said program is executed on a computer.

[0020] The invention also relates to any “hands-free” access equipment to a motor vehicle, capable of being worn by a user, characterized in that it comprises an accelerometer, means for measuring acceleration values ​​and means for transmitting acceleration values ​​at ultra high frequency.

[0021] And finally, the invention applies to any motor vehicle comprising an activation device according to any one of the characteristics listed above. [Description of the drawings]

[0022] Other characteristics and advantages of the invention will become apparent from reading the description which follows. This description is purely illustrative and must be read in conjunction with the appended drawings in which: [Fig. 1]: Figure 1 schematically represents the vehicle equipped with the activation device according to the invention, with portable equipment in a static position, located in a predetermined proximity around the vehicle, [Fig. 2]: Figure 2 schematically represents the vehicle equipped with the activation device according to the invention, with portable equipment in motion, the motion being greater than a threshold, located in a predetermined proximity around the vehicle, [Fig. 3]: Figure 3 schematically represents the vehicle equipped with the activation device according to the invention, with portable equipment in motion, the motion being between a minimum displacement and a threshold, located in a predetermined area around the vehicle. [Fig. 4]: Figure 4 schematically represents the activation device according to the invention, [Fig. 5]: Figure 5 is a flowchart representing the different stages of the activation method according to the invention. [Description of embodiments]

[0023] In Figure 1 is shown a motor vehicle V equipped with the activation device D according to the invention. The activation device D comprises at least two transmitter receivers EM1, EM2, EM3, EM4 in Ultra Wide Band ULB and in ultra High Frequency, of the Bluetooth, BLE type, capable of communicating in ultra wide band and in BLE with portable access equipment SD carried by a user U.

[0024] The activation device D further comprises a central control unit 10 electronically connected to all the Bluetooth LE and ULB transceivers EM1, EM2, EM3, EM4.

[0025] This central control unit 10 makes it possible to manage the transmission and reception of data in ULB, Bluetooth LE via the transmitter receivers. This is known from the prior art and will not be detailed further here.

[0026] Ultra Wide Band (UWB) communication is a radio frequency communication based on the transmission of very short pulses, often less than a nanosecond. Thus, the bandwidth can reach very high values ​​between 250 and 500 MHz.

[0027] Bluetooth LE communication means "Bluetooth Low Energy" (or Bluetooth low energy), an ultra-high frequency communication at around 2.4 GHz.

[0028] As already explained, the activation method of the prior art consists of: a. Detecting by Bluetooth LE communication the remote presence of the access equipment SD, i.e. around 100 m around the vehicle, V and establishing a first communication link by Bluetooth Low Energy between the access equipment SD and the activation device D, using at least one transmitter receiver, b. Receive in BLE an identifier of said SD equipment by the vehicle, and recognize the latter as being an identifier of a portable equipment previously associated with the vehicle V, c. Then detect by ULB communication, thanks to at least one transceiver of the activation device D, the close presence of the access equipment, that is to say in a close zone Z1 of the vehicle, for example between 0 and 15 m around the vehicle, and precisely locate the position of said SD equipment, d. Activate a vehicle function F1 according to the distance separating said SD equipment from the vehicle V, for example automatically unlock the door when the user is near the door, or turn on the air conditioning, heating, radio or remotely control the vehicle V for the automatic parking mode, when the user U is a few meters from his vehicle.

[0029] As explained previously, if the SD access equipment is within the Ultra Wide Band ULB communication range, the vehicle function is activated even if the user did not want it, which poses a real problem in terms of security and battery life.

[0030] The invention proposes an activation device D overcoming the drawbacks of the prior art.

[0031] According to the invention, the “hands-free” access equipment SD comprises an integrated accelerometer ACC and is capable of measuring acceleration values ​​over time t and of transmitting said values ​​to the activation device D.

[0032] The SD access equipment also comprises a processor 200 and a memory 201 (see FIG. 4) in which instructions are recorded making it possible to configure the processor to execute certain particular processing operations, in particular to implement the steps of the activation method, according to the embodiment as described below.

[0033] According to the invention, the activation device D further comprises (see figure 4): a. means for detecting M1 by ultra high frequency a presence of the access equipment SD in a predetermined zone Z1, b. means for authenticating M2 in ultra high frequency said equipment SD, c. means for receiving M3 in ultra high frequency the acceleration values ​​coming from said equipment SD, d. means for stopping or maintaining the communication in ultra high frequency M4 and for triggering M5 the communication in ultra wide band according to said acceleration values.

[0034] In an improvement of the invention, the activation device further comprises means M6 for reducing an ultra wide band ULB communication frequency as a function of said acceleration values.

[0035] Preferably, but in no way limiting, the detection means M1, the authentication means M2, the reception means M3 and the means M4 for stopping or maintaining the ultra high frequency communication and the means M5 for triggering the ultra wide band communication are included in the central control unit 10 (see figure 4) and are presented partially or entirely in the form of software.

[0036] The central control unit 10 also comprises a processor 100 and a memory 101 (see FIG. 4) in which instructions are recorded making it possible to configure the processor to execute certain particular processes, in particular to implement the steps of the activation method, according to the embodiment as described below.

[0037] The detection means M1 consist of means for transmitting, receiving and processing data received from the access equipment SD by ultra high frequency, included in the transmitters and receivers EM1, EM2, EM3, EM4 and in the central control unit 10. Said means make it possible to detect the presence of said equipment in a predetermined zone Z1 around the vehicle with a radius of 10 m to 15 m. This is known from the prior art.

[0038] The authentication means are presented in the form of software allowing the recognition of the ID identifier of the SD access equipment, and authenticating it in order to detect whether said equipment is authorized to activate the functions of the vehicle V. This is known from the prior art.

[0039] The means of reception M3 of the acceleration values ​​ACC(t) from the access equipment consist of the transmitters receivers EM1, EM2, EM3, EM4 and the central control unit 10.

[0040] The means for stopping or maintaining communication in ultra high frequency BLE M4 and for triggering M5 communication in ultra wide band ULB according to the said acceleration values ​​are in the form of software.

[0041] More particularly, upon receipt of the acceleration values ​​according to the time ACC(t), the activation device D determines a displacement d1, d2 (see figures 2 and 3) or a distance traveled d of the activation device D according to the time, more particularly since the last static position of said equipment which was memorized.

[0042] The determination of a displacement d1, d2 from a previous position P1 of the access equipment SD using the acceleration values ​​ACC(t) is known to those skilled in the art. Those skilled in the art know how to calculate a distance d1, d2 on the basis of acceleration values ​​ACC(t) over time and a starting position, so this will not be detailed here.

[0043] The means for stopping or maintaining M4 the communication in ultra high frequency M4 and for triggering M5 the communication in ultra wide band ULB as a function of said acceleration values ​​ACC(t) therefore comprise: a. Means for calculating a distance traveled d1, d2 by the access equipment SD as a function of said acceleration data, b. Means for comparing said distance d1, d2 with a threshold value ds, for example ds is equal to 50 cm. c. Means for stopping the communication in ultra high frequency BLE and for triggering the communication in ultra wide band ULB if the distance d1, d2 is greater than the threshold value ds, d. Means for maintaining the communication in ultra high frequency BLE, if the distance d1, d2 is less than the threshold value ds.

[0044] In an improvement of the invention, the activation device D further comprises: a. Means for comparing M7 said distance d1, d2 with a minimum displacement value dmin, b. Means for stopping the communication in ultra high frequency BLE and for starting the communication in ultra wide band BLE with a reduced transmission frequency F M8, if the distance d1, d2 is greater than the minimum displacement dmin but less than the threshold value ds.

[0045] This will be explained below.

[0046] The activation method according to the invention which is illustrated in Figure 5 will now be described.

[0047] In a preliminary step EO, an ultra-high frequency BLE communication is established between the activation device D and the access equipment SD. This communication is made possible because the access equipment SD is located in a predetermined area Z1 around the vehicle which is included in the BLE communication range of the vehicle V.

[0048] In a first step E1, the access equipment SD is authenticated, for this it exchanges by ultra high frequency communication its own identifier ID with the activation device D which verifies that said equipment has been paired beforehand with the vehicle and is authorized to activate vehicle functions.

[0049] In a second step E2, the access equipment measures according to time t and stores acceleration values ​​ACC(t) using its integrated ACC accelerometer.

[0050] Preferably, the acceleration measurements ACC(t) are carried out continuously, stored and transmitted to the activation device D.

[0051] The distance traveled d1, d2 is determined by the activation device D from a previous static position of the equipment SD which has been previously stored for a predetermined duration At. For example, the access equipment SD has remained in a static position for At=5s, and therefore its acceleration values ​​have not changed during this predetermined duration, the next estimation of distance traveled d will be carried out from this static position, and from the acceleration measurements of the access equipment SD which have been received by the activation device D from said static position.

[0052] The calculation of distance traveled d1, d2 is carried out continuously or at a fixed frequency.

[0053] In a third step 3a, the distance traveled d1, d2 thus estimated using the acceleration values ​​received from the last stored static position is compared to a threshold value ds. For example ds=50 cm.

[0054] If the distance traveled d1, d2 from the last static position is greater than the threshold value of 50 cm, then the ultra high frequency BLE communication is stopped and the ultra wide band ULB communication is started (step E4c). This is illustrated in Figure 2, the distance traveled d1 from the static position P1 is greater than ds=50 cm.

[0055] In fact, it is then considered that the user has moved significantly in relation to his vehicle and therefore wishes to activate a vehicle function.

[0056] ULB communication then makes it possible to locate the SD access equipment more precisely around the vehicle V in the predetermined zone Z1, and to activate a vehicle function depending on its position (step E5c).

[0057] If the distance traveled d1, d2 since the last static position is less than the threshold value ds of 50 cm, then the BLE ultra high frequency communication is maintained (step E4a). Indeed, in this case, the movement of the user is not considered significant, and sufficient to detect an intention to activate a vehicle function. The BLE communication is therefore maintained and the method returns to step E0 of ultra high frequency communication.

[0058] In an improvement of the invention, if the distance traveled d1, d2 from the last static position is less than the threshold value ds of 50 cm, but greater than a minimum displacement for example dmin of 10 cm (step E3b), then the communication in ultra high frequency BLE is stopped and the communication in ultra wide band ULB is started but with a reduced transmission frequency Fmin (step E4b). Otherwise the communication in ultra high frequency BLE is maintained.

[0059] For example, the transmission frequency in ultra wideband ULB is around 10Hz and the reduced transmission frequency in ULB Fmin can be around 2Hz.

[0060] In this case, it is considered that the user has moved or has started to move, so it is advisable to activate the communication in ultra wide band ULB. However, as the movement is of low amplitude, it is preferable to reduce the transmission frequency in order to reduce the energy consumption of the batteries. This is illustrated in figure 3, the distance traveled d2 from the static position P3 is between 20 cm and 50 cm.

[0061] The invention is particularly ingenious because it significantly reduces the risk of vehicle theft and increases the battery life of the access equipment and, to a lesser extent, that of the vehicle.

[0062] ULB communication is only activated when significant movement of the user is detected.

[0063] The invention is particularly easy to implement and inexpensive, because the device primarily comprises software means.

Claims

Claims

1. Method for activating a vehicle function, by an activation device (D), from a “hands-free” access equipment (SD) capable of being worn by a user (U), the access equipment being provided with an accelerometer (ACC), the activation of the function being triggered by a detection of the presence of the equipment (SD) in a predetermined zone (Z1) around the vehicle (V), and as a function of an authentication result of the equipment (SD), the activation device comprising at least one transceiver (EM1, EM2, EM3, EM4) capable of communicating with said equipment in ultra wide band (ULB), and in ultra high frequency (BLE), the method being characterized in that it comprises the following steps: a) Detection by ultra high frequency (BLE) communication, of a presence of the access equipment (SD) in a predetermined zone (Z1) around the vehicle (step E0),b) Authentication of said equipment (step E1) by ultra high frequency communication, c) Acceleration measurements of the access equipment (step E2), and i) upon receipt of the acceleration values according to time ACC(t), the activation device (D) determines a displacement or a distance traveled according to time, from a last fixed position of said equipment which has been stored, ii) If said measurements (ACC(t)) are representative of a movement of the access equipment (SD) between a minimum displacement (dmin) and the threshold (ds) (step E3b), then stopping of the ultra high frequency communication and triggering of the ultra wide band (ULB) communication at a reduced transmission frequency (Fmin) and activation of the vehicle function (step 5c) according to the position of the access equipment (SD), iii) Otherwise, if said measurements (ACC(t)) are representative of a static state of the access equipment (SD),from a last fixed position then maintaining communication in ultra high frequency (step 4a).,

2. Activation method according to any one of the preceding claims, characterized in that said acceleration measurements are transmitted by the access equipment (SD) to the activation device (D).

3. Activation device (D) for a function of a motor vehicle (V) intended to be on board the vehicle, the activation of the function being triggered by a detection of the presence of a portable “hands-free” access device (SD), capable of being carried by a user (U), in a predetermined zone (Z1) around the vehicle (V), and as a function of a result of authentication of said equipment by the vehicle (V), the activation device comprising at least one transmitter receiver (EM1, EM2, EM3, EM4) for transmitting and receiving in Ultra Wide Band (ULB) and in ultra high frequency (BLE) capable of communicating with said equipment in ultra wide band and in ultra high frequency, the device being characterized in that it further comprises: a) means (M1) for detecting by ultra high frequency a presence of the access equipment (SD) in a predetermined zone (Z1), b) means (M2) for authenticating in ultra high frequency said equipment,c) Means for receiving (M3) in ultra high frequency acceleration values (ACC(t)) from said equipment, d) Means for stopping (M4) or maintaining communication in ultra high frequency and for triggering (M5) communication in ultra wide band as a function of said acceleration values from a last fixed position. e) means for triggering communication in ultra wide band (M8) with a reduced frequency (Fmin) as a function of said acceleration values from a last fixed position if said measurements (ACC(t)) are representative of a movement of the access equipment (SD) between a minimum displacement (dmin) and the threshold (ds).,

4. Motor vehicle (V), characterized in that it comprises an activation device (D) according to the preceding claim.

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