Securing access to a vehicle's remote control function by a smartphone

Abstract

The invention relates to a method for securing access to a remote control function of a vehicle (1) by a smartphone (2) comprising the following steps: - determining the vertical component (dZ) of the distance (d) between the vehicle (1) and the smartphone (2) by the difference between a barometric altitude measured on the vehicle (1) and a barometric altitude measured on the smartphone (2), - authorizing access if the vertical component (dZ) is substantially zero. The invention also relates to a device implementing such a method. Abstract figure: Figure 1

Description

Title of the invention: Securing access to a remote control function of a vehicle by a smartphone Technical field

[0001] The invention relates to a method and a device for securing access to a remote control function of a vehicle by a smartphone.

[0002] Such a function is controlled by a user using his smartphone, when the user is a few meters away from the vehicle.

[0003] An example of such a function is an automatic parking exit function. The user is located a few meters from his vehicle, typically in a public parking lot, where the vehicle is parked. When the user commands the function, the vehicle autonomously leaves its parking space and moves into the adjacent lane, where the user can get into the cockpit and resume driving. Prior art

[0004] It is known to measure a distance between two objects, such as a vehicle and a smartphone, both equipped with a ULB communication unit, by measuring time of flight.

[0005] It is known to condition an authorization of access to a remote control function of a vehicle by a smartphone, on a condition of distance between the vehicle and the smartphone included in a given interval. This distance must typically be a few meters in the XY plane, to ensure on the one hand that the user is in sight of his vehicle (not too far) and on the other hand to protect the user when the vehicle is moving (not too close), with a zero component in Z. Indeed, it is not desired to trigger the function if the user is above or below his vehicle, but on a different floor.

[0006] However, a ULB time-of-flight measurement turns out to be very imprecise in the vertical or Z direction for several reasons.

[0007] A first reason is that superimposed parking lots are very opaque to radiofrequency waves, due to the construction of the floors in metal, as in Japan, or in reinforced concrete.

[0008] Another reason is algorithmic. To obtain a 3D distance, it is necessary to intersect at least three spheres. However, the ULB communication units on board the vehicle are not optimized for downward transmission, the metal chassis of the vehicle forming a shield against propagation.

[0009] Another reason is that despite the presence of several communication units on board the vehicle, these units are substantially in the same plane, thus reducing the Z resolution.

[0010] Also, an alternative to the sole measurement of distance by flight time is sought to determine the position of the user and his smartphone relative to the vehicle and to grant or deny him access. Summary of the invention

[0011] For this purpose, the invention relates to a method for securing access to a remote control function of a vehicle 1 by a smartphone 2 comprising the following steps: - determination of the vertical component of the distance between the vehicle and the smartphone by difference between a barometric altitude measured on the vehicle and a barometric altitude measured on the smartphone, - authorization of access if the vertical component is substantially zero.

[0012] Particular characteristics or embodiments, usable alone or in combination, are: - the nullity of the vertical component is assessed with a tolerance of + / - 1.5 m, preferably + / - 0.5 m, - the barometric altitude difference is calibrated when the smartphone leaves the vehicle, - the method also includes the following steps: - determination of the horizontal component of the distance by measuring the flight time using ULB modulation, - calculation of the distance, - authorization of access if the distance is above a minimum threshold and / or below a maximum threshold, - the minimum threshold is approximately equal to 4 m and the maximum threshold is approximately equal to 6 m, - the method also comprises the following step: - authorizing access if the smartphone is in control mode, the control mode being characterized by an orientation of the smartphone indicative of being held in the hand, - the method also includes the following step: - authorization of access if the speed and / or acceleration of the vehicle is substantially zero.

[0013] According to another aspect, a device for securing access to a remote control function of a vehicle by a smartphone, comprising an application, distributed between the vehicle and the smartphone, implementing the method according to any one of the preceding claims. Brief description of the drawings

[0014] The invention will be better understood on reading the following description, given solely by way of example, and with reference to the appended figures in which:

[0015] [Fig-1] shows, in synoptic view, the environment of the invention,

[0016] [Fig.2] shows, in schematic view, the control mode of the smartphone,

[0017] [Fig.3] shows, in synoptic view, the functional organization of the processing. Description of the embodiments

[0018] With reference to [Fig.l], the invention relates to a function for remote control of a vehicle 1 by a user using his smartphone 2.

[0019] By way of illustration, the remote control function may be a parking or PRK function, making it possible to park or unpark a vehicle 1 autonomously, the driver being outside the vehicle 1.

[0020] More particularly, the invention relates to securing access to this remote control function.

[0021] The method for securing access to the remote control function comprises one or more conditions which must be cumulatively met before the function can be accessed and triggered. The order in which the different conditions are tested may be arbitrary.

[0022] It can still be optimized, for example, to test the conditions in increasing order of their probability of occurrence, i.e. from the least frequently occurring condition to the most frequently occurring condition, so as to reduce the calculation time as much as possible.

[0023] Alternatively, the conditions may be tested in parallel, or any other parallel and series combination.

[0024] According to a first characteristic, it is verified that the user is substantially at the same altitude as the vehicle 1. For this, it is assumed that the user is the same as his smartphone 2, in terms of location. In other words, it is assumed that the smartphone 2 is carried, in the pocket or in the hand, by the user. The altitude verification is carried out by means of the following steps. During a first step, the vertical component dZ of the distance d between the vehicle 1 and the smartphone 2 is determined.

[0025] In view of the difficulties / impossibilities of obtaining this measurement by ULB flight time with sufficient precision, according to a particularly ingenious characteristic, this determination is carried out by an alternative approach: by difference between a barometric altitude or vehicle pressure PV, measured by a pressure sensor placed on the vehicle 1 and a barometric altitude or smartphone pressure PO, measured by a pressure sensor placed on the smartphone 2. It is desired only be able to trigger the function remotely when the user, and therefore their smartphone 2, is on the same floor as vehicle 1.

[0026] Also, access authorization is granted only if the vertical component dZ is substantially zero. Also, the difference AP between the vehicle pressure PV and the smartphone pressure PO is calculated, AP = PV - PO, then converted into altitude.

[0027] In order to take into account a variation in the size of the user and a variation in the location of the smartphone 2: in hand, in a low pocket, in a high pocket, according to another characteristic, a tolerance of + / - 50 cm can be applied. A wider tolerance can still be applied, as long as it remains lower than the average height of a parking floor. Thus, if such an average height is substantially equal to 3 m, a tolerance of + / - 1.5 m can be applied.

[0028] In order to obtain and maintain sufficient precision in the measurement of the barometric altitude difference, the latter, according to another characteristic, is advantageously calibrated when the smartphone 2 leaves the vehicle 1.

[0029] This calibration can be carried out in the following manner. When the smartphone 2 leaves the vehicle 1, typically detected by a distance, or by a locking of the vehicle 1 or any other indication indicating that the user, and therefore supposedly his smartphone 2, are going to leave the proximity of the vehicle 1, a measurement of the barometric altitude difference or dZ0 is carried out. Since, at this moment, the user is assumed to be at the same altitude as his vehicle 1, this measurement dZ0 must correspond to a zero altitude difference. The calibration consists of memorizing the value of dZ0 as a correction offset for subsequent measurements. Thus, a subsequent measurement, for example when the user returns to his vehicle 1, determines a raw measurement dZ by difference of the pressures PV, PO, and corrects it by subtracting the offset dZ0, the corrected measurement dZ' being equal to dZ- dZ0. Each calibration recalculates the offset dZ0.

[0030] This calibration can be carried out regularly, at each departure, or every n departures or even as soon as a certain time has elapsed since the last calibration.

[0031] A second condition can be tested. A second condition can be a distance condition. Before performing the remote function, it may be interesting to validate one (or two) distance conditions of the user and his smartphone 2 to the vehicle 1.

[0032] To do this, the following steps are followed. In a first step, the horizontal component dX, dY of the distance d is determined. The horizontal component can be expressed in a Cartesian frame, dX, dY. It should be understood more generally as the horizontal component in any frame, for example dR, in a polar frame. Depending on the determination technology, this horizontal component can be obtained in a frame and then converted into another. This determination is advantageously carried out by measuring flight time according to a ULB modulation. This measurement by ULB flight time, in a horizontal plane, does not pose the problems mentioned previously for the vertical component dZ. Indeed, and mainly, when the smartphone 2 and the vehicle 1 are at the same altitude, the ULB propagation takes place substantially in direct view (or LOS, from the English "line of sight") or at least with a low density of obstacles, as in the case considered of a parking lot, presenting few obstacles / walls and narrow posts.

[0033] From this horizontal component dX, dY, dR the distance d can be calculated, during another step.

[0034] Then, during another step, this distance d is compared with a minimum threshold Sm and / or with a maximum threshold SM. The maximum threshold SM defines a distance d lower than this threshold SM and therefore prohibits the triggering of the control function when the user is too far from the vehicle 1. This contributes to a safety measure against involuntary triggering by the user. In addition, this can ensure that the user is sufficiently close to the vehicle 1 to monitor or see the progress of the control function or even be ready to board, at the end of the control function.

[0035] The minimum threshold Sm defines a distance d greater than this threshold Sm and therefore prohibits the triggering of the control function when the user is too close to the vehicle 1. This may aim to guarantee the physical safety of the user, by moving him away, when the control function produces a potentially vulnerable movement of the vehicle 1.

[0036] During the last step, access is authorized if the distance d is greater than the possible minimum threshold Sm and if the distance is also less than the possible maximum threshold SM.

[0037] According to another characteristic, more particularly adapted to the PRK parking function, the minimum threshold Sm is substantially equal to 4 m and the maximum threshold SM is substantially equal to 6 m.

[0038] A third condition can be tested. According to another characteristic, a third condition verifies that the smartphone 2 is in control mode. This condition is more particularly illustrated in [Fig. 2] and aims to avoid untimely triggering. For this, during a first step, the orientation of the smartphone 2 is observed. The smartphone 2 is in control mode when its orientation corresponds to being held in the hand, as opposed to a position where the smartphone 2 is stored, typically in a user's pocket. The smartphone 2 can also, optionally, be considered in control mode when it is active and woken up by a recent interaction. of the user, as opposed to a sleep or economy mode following an absence of interaction for a certain period of time.

[0039] During a final step, access is authorized if the smartphone 2 is in control mode, i.e. when the smartphone 2 is observed in an orientation belonging to the orientations associated with the control mode. This condition makes it possible to ensure that the user really intends to use the remote control function and that it is not a false trigger, triggered by accidental contact of the touch screen of the smartphone 2 with the pocket.

[0040] A fourth condition can be tested. A fourth condition can be a stationary vehicle 1 condition. For this, the processing unit 13 checks that the vehicle is not in a state of motion by observing its speed and / or its acceleration and verifying that they are zero. This makes it possible to avoid triggering the function in the case of a vehicle in motion or transported by a robot elevator in an automatic parking lot. This condition checks that the speed V and / or the acceleration of the vehicle 1 is / are zero, or that the vehicle 1 is stationary. This condition is intended to avoid untimely triggering of the control function, while the vehicle 1 is moving, under its own power or in the process of being moved by an external means. Thus, a zero speed and / or zero acceleration is an initial condition of the remote control function.Thus, during a first step, the speed V and / or the acceleration of the vehicle 1 is / are measured or recorded at the processing unit 13 of the vehicle 1. During another step, access is authorized if the speed V and / or the acceleration of the vehicle 1 is / are substantially zero.

[0041] The invention also relates to a device for securing access to a remote control function of a vehicle 1 by a smartphone 2. This device is characterized in that it comprises an application, distributed between the vehicle 1 and the smartphone 2. This application implements the method for securing access to a control function described above.

[0042] [Fig. 3] illustrates a functional breakdown of the processing units of the device. It is articulated between a vehicle block 11-15, on the right of the diagram and a smartphone block 21-25, on the left of the diagram.

[0043] The vehicle block 11-15 is articulated around a vehicle processing unit 13. This vehicle processing unit 13 is integrated into the vehicle ECU. It interfaces a vehicle pressure sensor 11, to measure the vehicle atmospheric pressure PV useful for determining the vertical component dZ. It further interfaces a vehicle orientation / position sensor 12. It further interfaces a vehicle BLE transmission unit 14 allowing it to exchange with the smartphone 2 according to a first channel 3. BLE here means “Bluetooth Low Energy”, i.e. a transmission protocol derived from Bluetooth and optimized to be low energy consuming. It interfaces still a vehicle ULB transmission unit 15 allowing it to exchange with the smartphone 2 according to a second channel 4 and allowing time-of-flight measurements. ULB here designates a radiofrequency transmission according to an Ultra Wide Band modulation, in English “Ultra Wide Band” or UWB.

[0044] The smartphone block 21-25 is articulated around a smartphone processing unit 23. This smartphone processing unit 23 is integrated into the smartphone SoC. It interfaces a smartphone pressure sensor 21, to measure the smartphone atmospheric pressure PO useful for determining the vertical component dZ. It also interfaces a smartphone orientation / position sensor 22. This sensor, also called IMU, from the English "Inertial Measurement Unit", includes gyrometers and accelerometers capable of determining the orientation of the smartphone 2. This sensor makes it possible to determine whether the smartphone 2 is in control mode. The smartphone processing unit 23 further interfaces a smartphone BLE transmission unit 24 allowing it to exchange with the vehicle 1 according to the first channel 3. It further interfaces a smartphone ULB transmission unit 25 allowing it to exchange with the vehicle 1 according to the second channel 4 and allowing time-of-flight measurements.

[0045] The invention has been illustrated and described in detail in the drawings and the preceding description. This should be considered as illustrative and given by way of example and not as limiting the invention to this description alone. Numerous alternative embodiments are possible. List of reference signs

[0046] 1: vehicle, 2: smartphone, 3: BLE link, 4: ULB link, 11: vehicle pressure sensor, 12: vehicle inertial unit, 13: vehicle processing unit, 14: vehicle BLE transmission unit, 15: vehicle ULB transmission unit, 21: smartphone pressure sensor, 22: inertial unit ordiphone, 23: smartphone processing unit, 24: BLE smartphone transmission unit, 25: ULB smartphone transmission unit, d: vehicle smartphone distance, AP: differential pressure, dR, dX, dY: horizontal component of the distance, dZ: vertical component of the distance, dZ': vertical component of the distance corrected for the offset, dZ0: offset of the vertical component, ECU: from the English “Electronic Control Unit” meaning electronic processing unit, PO: atmospheric pressure smartphone, PRK: parking function, PV: vehicle atmospheric pressure, Sm: minimum threshold, SM: maximum threshold, SoC: from the English “System on a Chip”, processor of a smartphone, V: vehicle speed.

Claims

Claims

1. Method for securing access to a remote control function of a vehicle (1) by a smartphone (2), characterized in that it comprises the following steps: - determination of the vertical component (dZ) of the distance (d) between the vehicle (1) and the smartphone (2) by difference between a barometric altitude (PV) measured on the vehicle (1) and a barometric altitude (PO) measured on the smartphone (2), - authorization of access if the vertical component (dZ) is substantially zero.

2. Method according to claim 1, where the nullity of the vertical component (dZ) is assessed with a tolerance of + / - 1.5 m, preferably + / - 0.5 m.

3. A method according to any one of claims 1 or 2, wherein the barometric altitude difference is calibrated when the smartphone (2) leaves the vehicle (1).

4. Method according to any one of claims 1 to 3, further comprising the following steps: - determination of the horizontal component (dX, dY) of the distance by measuring the time of flight according to a ULB modulation, - calculation of the distance (d), - authorization of access if the distance (d) is located above a minimum threshold (Sm) and / or below a maximum threshold (SM).

5. A method according to claim 4, wherein the minimum threshold (Sm) is substantially equal to 4 m and the maximum threshold (SM) is substantially equal to 6 m.

6. Method according to any one of claims 1 to 5, further comprising the following step: - authorizing access if the smartphone (2) is in control mode, the control mode being characterized by an orientation of the smartphone (2) indicative of being held in the hand.

7. Method according to any one of claims 1 to 6, further comprising the following step: - authorizing access if the speed (V) and / or the acceleration of the vehicle (1) is substantially zero.

8. Device for securing access to a remote control function of a vehicle (1) by a smartphone (2), characterized in that it comprises an application, distributed between the vehicle (1) and the smartphone (2) implementing the method according to any one of the preceding claims.

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