FR3119908A1 - Control device for controlling at least one parameter among a plurality of parameters in a motor vehicle - Google Patents

Abstract

The invention relates to a control device (100) for controlling at least one parameter (P) among a plurality of parameters in a motor vehicle (10), said control device (100) comprising: a transmission module (110) adapted to transmit command data (z), a capacitive touch screen (1202) adapted to receive said command data (z) via a part of a body of a user of the motor vehicle (10), said part of the user's body being in contact with said screen (1202) at the level of a contact point, a module (12011) for determining the parameter (P) to be controlled according to the position of the contact on the capacitive touch screen (1202), a module (12012) for controlling the parameter (P) from the command data (z) if the user is authorized to control the said parameter (P) in the said motor vehicle ( 10). Figure for abstract: Fig. 2

Description

Control device for controlling at least one parameter among a plurality of parameters in a motor vehicle

The present invention relates to a control device for controlling at least one parameter among a plurality of parameters in a motor vehicle, an associated control method, a computer program product comprising program instructions usable by said control device and a motor vehicle comprising said control device.

The invention lies, more particularly, in the field of user interfaces having privileged access rights.

Touchscreens are commonly used in automotive vehicles today. These touch screens replace control buttons while bringing a qualitative side to the interior of the vehicle. The touch screen thus allows a user to be able to control various parameters in the vehicle by simply pressing on this screen. These parameters are, for example, driving parameters (driving modes, activation of driving assistance functions, etc.) or entertainment parameters (FM radio, playing a film on a screen, etc.) . However, permissions to change such settings may be limited. Thus, the driving parameters should only be modifiable by the driver, while the viewing of a film should only be accessible to a passenger. On the other hand, the radio must be able to be modified by any user in the vehicle (driver or passenger). It is therefore necessary to be able to accurately authenticate the person touching the touch screen in order to determine his right to modify or not one of the parameters.

There are many physical means of authentication. A first solution consists in using biometric data specific to the authentic user. One possibility is thus to carry out a biometric control of this data by equipment comprising a data reader (for example a fingerprint reader) forming a dedicated base, each time the user wishes to carry out an operation. However, the security of such a system is limited. In particular, authentication relies entirely on a measurement performed by a database which may have storage security flaws. Thus during each authentication, it is necessary to reproduce the biometric measurement. Moreover, such a system can only authenticate the user on the basis of the particular biometric data (for example the fingerprint) that the database used for authentication is capable of storing. Moreover, biometric mechanisms bring additional mechanical/spatial constraints to the user. Indeed, fingerprint recognition requires the user asking to be authenticated to place a finger on a cell located in a specific place. The user cannot be authenticated if he does not put his finger in the right place.

The document WO2014020087 discloses an authentication module allowing highly secure authentication of a person while offering great flexibility of use and great ease of use. The authentication of this person is based on one of his physiological characteristics such as body temperature, heart rate or skin conductivity. However, such physiological characteristics may vary over time, which makes authentication repeatability more complicated. In addition, such an authentication module is difficult to embed in a motor vehicle.

There is therefore a need to propose a control device for controlling at least one parameter which is simple and practical to implement by a user (driver and/or passenger).

The present invention aims to at least partially remedy this need.

More particularly, the present invention aims to improve the authentication of persons in a vehicle for the modification of parameters.

A first object of the invention relates to a control device for controlling at least one parameter among a plurality of parameters in a motor vehicle, said control device comprising a transmission module suitable for transmitting command data, a capacitive touch screen adapted to receive said control data via a part of a body of a user of the motor vehicle, said part of the body of the user being in contact with said screen at a point contact, a module for determining the parameter to be controlled according to the position of the contact point on the capacitive touch screen and a parameter control module from the command data if the user is authorized to control said parameter in said vehicle automobile.

The invention thus makes it possible to combine two technologies, namely the technology of capacitive touch screens on the one hand and HBC-CC technology (for “Human Body Communication-Capacitive Coupling”). Capacitive touch screen technology is a screen technology used to detect the presence of a user's finger. It is a reference technology in the automobile. The principle is that a signal is detected at the sensors of the capacitive screen as soon as the user's finger approaches the screen. In capacitive touchscreens, an indium-based layer forms a capacitive plate. This capacitive plate is placed on a glass plate. When the user touches the glass plate with his finger, some of the charges of the capacitive plate are transferred. Charges leaving the capacitive plate create a quantifiable deficit. With a sensor at each of the corners of the capacitive plate, it is possible at any time to measure and determine the coordinates of the contact point. A major advantage of capacitive touch screens is their ability to let light through with greater efficiency. Indeed, up to 90% of the light passes through a capacitive surface which gives superior image clarity, especially compared to resistive technology. Capacitive touch screens are mainly used in smartphones and tablets.

HBC-CC technology uses the principle of a displacement current flowing between two HBC electrodes. More specifically, the displacement current circulates in the human body by entering and exiting through electrodes placed in close contact with it. The dielectric properties of the human body can therefore be used to transmit electrical information harmlessly and painlessly between two electrodes a few tens or hundreds of centimeters apart.

The control device then makes it possible to increase the information detectable by a capacitive touch screen beyond simple coordinates (x, y) representative of a press detected on the touch surface. The controller enhances the current capabilities of capacitive touch screens so that said screens can return a triplet (x, y, z) with x, y corresponding to the coordinates of the touch point on the screen, z a noise or a predefined message. The command data corresponds to a predefined message when the finger that presses on the screen belongs to a body of which another part presses on the other electrode located on the steering wheel. The flywheel electrode sends a predefined message periodically through the whole body in contact with said electrode (HBC-CC channel). If the body is also in contact with the screen through a finger, the predefined message will reach the finger and therefore the surface of the screen at the point of contact between the finger and the screen . The message present at the level of the finger will then be detectable by the electrode of the screen. If this is not the case, the screen electrode will pick up (x, y, noise) and deduce that the user pressing the screen is not the one holding the steering wheel. So it's not the driver. Thanks to the control device of the invention, it becomes possible to develop User Interfaces making it possible to control vehicle parameters allocating different rights according to the users, and more particularly, different rights between a user identified as being the driver of the car and a user not identified as the driver. The command data z can then also be considered as authentication data.

In a particular embodiment, the transmission module belongs to a steering wheel of the motor vehicle.

Thus, the identification of the driver is not done biometrically but based on the fact that the user touches both the steering wheel and the screen displaying the User Interface. It then becomes possible to display a menu allowing the choice to control driving parameters or parameters linked to the FM radio, or to navigation, for example, and to ensure that the menu making it possible to modify the driving parameters can only be activated by the driver alone, while the others can be activated by any user present in the car.

In a particular embodiment, the transmission module comprises an HBC electrode for the transmission of command data and the capacitive touch screen is adapted to act as a second electrode for the reception of said command data, the first electrode and said capacitive touch screen being connected to the same ground.

This allows better passage of the displacement current carrying the control data. This order data is basic. It is either one or more predefined messages or a noise.

In a particular embodiment, the capacitive touch screen is suitable for detecting the presence of the user's body part before contact between said body part and said screen.

Thus, it is possible to start the user control measures before an effective contact between the user's body and the screen.

Another object of the invention relates to a control method for controlling at least one parameter among a plurality of parameters in a motor vehicle. The control method comprises a step of transmitting control data between a transmission module and a capacitive touch screen, said control data being adapted to be transported by a part of a body of a user of the motor vehicle, said part of the user's body being in contact with said screen at a contact point. The control method also comprises a step of determining the parameter to be controlled according to the position of the contact point on the capacitive touch screen and a step of controlling the parameter from the control data if the user is authorized to control said parameter in said motor vehicle.

The method thus makes it possible to convey in a simple and practical manner an electrically modulated message between an element of the motor vehicle (for example a steering wheel) and the capacitive touch screen, for the control of a parameter of the motor vehicle by a duly authorized user.

In a particular embodiment, the method comprises a step of querying an access rights management database to determine whether the user is authorized to control said parameter in the motor vehicle.

Thus, thanks to the method of the invention, it is possible to develop user interfaces making it possible to control parameters of the vehicle by allocating different rights according to the type of user (driver, passenger). What matters is the quality of the user more than his identity.

In a particular embodiment, the part of the user's body is in contact with the capacitive touch screen for a contact time greater than or equal to one second.

Thus, the signal emitted by the steering wheel has sufficient time to reach the contact screen.

Another object of the invention relates to a computer program product comprising program instructions usable by the control device which, when they are executed or interpreted by said control device, trigger the implementation of a control method for the control of said at least parameter in the motor vehicle.

Another object of the invention relates to a motor vehicle comprising a control device for controlling at least one parameter among a plurality of parameters.

The present invention will be better understood on reading the detailed description of embodiments taken by way of non-limiting examples and illustrated by the appended drawings in which:

there is a partial view of a passenger compartment of a motor vehicle according to the invention;

there schematically illustrates a control device for controlling at least one parameter in the motor vehicle of the ;

there illustrates a first signal type detected at the level of a capacitive touch screen belonging to the control device of the ;

there illustrates a second type of signal detected at the level of the capacitive touch screen belonging to the control device of the ;

there illustrates the different steps of a control method implemented by the control device of the .

The invention is not limited to the embodiments and variants presented and other embodiments and variants will appear clearly to those skilled in the art.

In the various figures, identical or similar elements bear the same references.

There is a partial view of a passenger compartment of a motor vehicle 10. The motor vehicle 10 comprises a control device 100 for controlling at least one parameter, such as a driving parameter or an entertainment parameter. As illustrated in Figures 1 and 2, controller 100 includes:
- a transmission module 110;
- a receiving module 120;
- a 130 bus.

The transmission module 110 is suitable for transmitting command data z. The reception module 120 is adapted to receive these command data z.

This transmission module 110 comprises:
- a transmitter unit 1101;
- an HBC 1102 electrode.

Transmitter block 1101 is adapted to generate an electrically modulated message M _mod .

The electrode 1102 is adapted to receive the electrically modulated message M_modand to transmit it to the reception module 120 in the form of the command data z through the user's body.

The transmitter block 1101 includes:
- a generation 11011 sub-block;
- a modulation sub-block 11012.

The generation sub-block 11011 is suitable for periodically generating a stream of binary information T _inf . In a particular embodiment, this train of binary information T _inf is short and predefined. This train of binary information is, for example, about ten bits per second, encoded in OOK (for “on-off keying”) at 100-200 KHz. Encoding in OOK is characterized by the sending of a sinusoid for the duration of a type 1 bit and by the absence of a signal sent for the duration of a type 0 bit. T _inf is then transmitted on the one hand to the modulation sub-block 11012 and on the other hand to the reception module 120 via the bus 130. This bus 130 is, for example, a CAN data bus (for "Controller Area Network " in English).

Modulation sub-block 11012 is adapted to receive the binary information train Tinf from block 11011 and to transform said information train Tinf into an electrically modulated message Mmod. This electrically modulated message Mmod is then carried on a displacement current through the user's body. The train of binary information Tinf is short enough for the electrically modulated message Mmod to be transmitted in 1 to 2 seconds between two electrodes. In the case of the , the user is the driver of the motor vehicle and the HBC electrode 1102 is installed in a steering wheel.

In a particular embodiment, the first electrode 1102 has a shape adapted to said steering wheel.

The reception module 120 is adapted to receive the command data z transmitted by the transmission module 110.

This receiving module 120 includes:
- a processing block 1201;
- a 1202 capacitive touch screen.

The capacitive touch screen 1202 is adapted to receive the command data z when the driver comes to touch the touch screen, for example using one of his fingers. This capacitive touch screen 1202 comprises a plurality of sensors able to detect the contact between this finger of the user and the screen 1202. The illustrates a first type of signal S1 detected at the sensors of the screen 1202. This first type of signal S1 corresponds to a Gaussian. More particularly, this signal S1 comprises a first detection line 31, a second detection line 32 and a main lobe 33 disposed between the first detection line 31 and the second detection line 32. This main lobe 33 corresponds to the instant when the user's finger touches the capacitive touch screen 1202. In this first type of signal S1, the first detection line 31 and the second detection line 32 are globally stable and the signal S1 conveys command data z of type noise. We thus find ourselves in the case where the user who presses the capacitive touch screen 1202 does not touch the steering wheel electrode at the same time. There illustrates a second type of signal S2. This second type of signal S2 corresponds to a Gaussian with a plurality of secondary lobes 44. This second signal S2 also comprises a first detection line 41, a main lobe 43 and a second detection line 42. In the case of the , the first detection line 41 and the second detection line 42 comprise the secondary lobes 44. These secondary lobes 44 comprise information correlated to the predefined message of the control data z. We thus find ourselves in the case where the user who presses on the capacitive touch screen 1202 is also in contact with the electrode of the steering wheel. Capacitive touch screen 1202 acts as a receiving electrode. It is suitable for detecting the main lobe, that is to say the Gaussian which will give the coordinates x, y as well as all the secondary lobes if these are present. If secondary lobes are present (case of the ) the capacitive touch screen 1202 is suitable for obtaining the electrically modulated message Mmod from the command data z conveyed by the signal S2, for example by digital processing based on filtering and convolution.

The processing block 1201 of the reception module 120 is adapted to process the electrically modulated message M _mod and to transmit a control signal S _Pilot in order to control the determined parameter P. As a reminder, this determined parameter P can be a parameter of driving (driving modes, activation of driving assistance functions, etc.) or an entertainment parameter (FM radio, playing a film on a screen, etc.).

This processing block 1201 comprises:
- a module 12011 for determining the parameter P to be checked;
- a module 12012 for generating an S _Pilot control signal;
- a database 12013 of access rights.

The 12011 module is suitable for determining the P parameter to be controlled according to the position (x, y) of the contact point on the capacitive touch screen.

The 12012 module is suitable for generating a control signal S _pilot depending on the selected parameter P, the presence of command data z (case where the user is the driver) or the absence of this data z (case where the user is a passenger), and access rights R associated with the driver or the passenger.

In a first case where the user is the passenger, the control signal z corresponds to noise. Indeed, the passenger's hand is not in contact with the steering wheel, this passenger cannot therefore transmit a signal coming from the HBC 1102 electrode. The capacitive touch screen detects a point of contact with a finger of the passenger and the pair of coordinates (x, y) of this contact point is transmitted to the module 12011 for determining the parameter P. The information concerning the selected parameter P is then transmitted to the module 12012 for parameter control. Given that this module 12012 does not detect any electrically modulated message M _mod here, it is deduced that it is the passenger (ident1) who is touching the capacitive touch screen 1202. A pair of data (ident1, P) is then transmitted to the access rights database 12013 which in return gives or refuses the authorization R to send a control signal S _Pilot to an external module specifically managing the parameter P (for example a TV module controllable by the passenger but not controllable by the driver).

In a second case where the user is the driver, a command signal z of predefined message type is transmitted to the capacitive touch screen 1202. Indeed, the driver's hand is directly in contact with the steering wheel, the driver thus transmits a signal coming from the HBC electrode 1102. The capacitive touch screen detects a point of contact with a finger of the driver and the pair of coordinates (x, y) of this point of contact is transmitted to the module 12011 for determining the parameter P The information concerning the selected parameter P is then transmitted to the parameter control module 12012. In the same way, the electrically modulated message M _mod from the control signal z is transmitted to the module 12012.

This module 12012 is capable of decoding the electrically modulated message M _mod to extract therefrom the train of binary information T _inf . More specifically, the 12012 module extracts the secondary lobes. This stream of binary information is correlated with that previously transmitted by the bus 130. If the two streams of binary information are uncorrelated, this indicates that the command data z conveyed by the body of the user has been corrupted. Different solutions can be chosen. In a first solution, no control of the parameter P is carried out. In a second solution, the parameter P is checked if it is accessible to all users. If this parameter P is only accessible to the driver, no check is carried out. Alternatively, if the two streams of binary information are correlated, this indicates that the command data z conveyed by the body of the user is reliable and control of the parameter P can be achieved. It is thus deduced that it is the driver (ident2) who touches the capacitive touch screen 1202. A pair of data (ident2, P) is then transmitted to the database 12013 of access rights which in return gives or not the authorization R to send a control signal S _Pilot to an external module specifically managing the parameter P (for example a driving assistance module which is controllable by the driver but not controllable by the passenger).

It will be recalled that certain parameters can be controlled both by the passenger and by the driver, such as a radio parameter. The database 12013 is able to manage these different rights.

In a particular embodiment, it will be noted that the HBC electrode 1102 and the capacitive touch screen 1202 are connected to the same ground GND. This allows the receiver module 120 to more easily detect the signal carrying the z command data in the user's body.

In another particular embodiment, the capacitive touch screen 1202 is adapted to detect the presence of the user's finger before the contact between said finger and said screen. The capacitors of the screen 1202 closest to the finger measure an electrostatic peak that is all the greater the closer the finger is to the screen with a maximum value when the finger touches said screen.

There illustrates the different steps of the control method implemented by the control device 100 of the .

In a first step E1, the generation sub-block 11011 of the transmission module 110 periodically generates the train of binary information T _inf . This train of binary information T _inf is transmitted, in a second step E2, to the reception module 120 by the bus 130. Inside the reception module 120, this train of binary information T _inf becomes a reference value .

In a third step E3, the modulation sub-block 11012 modulates the train of binary information T _inf to form an electrically modulated message M _mod . If no driver is in contact with the steering wheel, the method resumes at the first step E1. If the driver is in contact with the steering wheel, the electrically modulated message M _mod is transmitted via the driver's body in a fourth step E4. In this case, two possibilities arise. Either the driver's body is not in contact with the capacitive touch screen 1202, and the process returns to the first step E1. Either the driver's body is in contact with the capacitive touch screen 1202 and the receiving module 120 receives, in a fifth step E5, the electrically modulated message M _mod at the point of contact between the driver's finger and the capacitive touch screen 1202. In a sixth step E6, the reception module 120 is adapted to determine the coordinates (x, y) of the point of contact on the capacitive touch screen 1202 and to consequently deduce the parameter P to be controlled according to the position of this contact point on the screen. Furthermore, in this sixth step E6, the reception module 120 decodes the electrically modulated message M _mod to extract therefrom the train of binary information T _inf . If this train of binary information is different from the reference value previously received via the bus 130, the database 12013 is consulted in a seventh step E7 and the parameter P is checked in an eighth step E8 if it is accessible to all users. If the train of binary information is equal to the reference value previously received via the bus 130, the database 2013 is consulted in a ninth step E9 and the parameter P is checked in a tenth step E10 according to the restrictions applied to each user (driver, passenger). At the end of the eighth step E8 and of the ninth step E9, the control method returns to the first step E1.

The control device for parameter control and the associated control method thus allow:
- to develop User Interfaces making it possible to control vehicle parameters by allocating different rights according to the users;
- to manage access rights without the user having to wear a biometric element, such as a bracelet. More than the identity of the user of the User Interface, what matters is the quality of the user (driver or not);
- to authenticate a user regardless of the point of impact between the finger and the screen;
- manage access rights transparently for the user;
- to decode the coordinates of the point of contact between the user and the touch surface of the screen 1202 (nominal function), to decode an additional message at this point of contact (the message emitted by the steering wheel) and to be able to establish that the point of contact does indeed come from the driver;
- to integrate within the same vehicle the transmission module 110 and the reception module 120, which makes it easier to connect the HBC electrode 1102 and the capacitive touch screen 1202 to the same ground GND.

The invention also relates to a computer program product comprising program instructions usable by the control device 100 for controlling the parameter P among a plurality of parameters in the motor vehicle 10, which when they are executed or interpreted by said control device trigger the implementation of the control method for controlling said at least parameter P in the motor vehicle 10.

The invention also relates to a motor vehicle comprising the control device for controlling the parameter P.

The invention is not limited to the embodiments and variants presented and other embodiments and variants will appear clearly to those skilled in the art.

Thus, the electrically modulated message M _mod can be of variable size, it can also be divided into several sub-messages. The User Interface would then be adapted to control the transmission module at the level of the steering wheel when necessary, and dictate to it the message frame to be sent.

Claims (9)

Control device for controlling at least one parameter (P) among a plurality of parameters in a motor vehicle (10), said control device (100) comprising:
- a transmission module (110) suitable for transmitting command data (z);
- a capacitive touch screen (1202) adapted to receive said command data (z) via a part of a body of a user of the motor vehicle (10), said part of the body of the user being in contact with said screen (1202) at a point of contact;
- a module (12011) for determining the parameter (P) to be controlled according to the position of the contact point on the capacitive touch screen (1202);
- a module (12012) for controlling parameter (P) from the command data (z) if the user is authorized to control said parameter (P) in said motor vehicle (10). Control device according to Claim 1, in which the transmission module (110) belongs to a steering wheel of the motor vehicle (10). Control device according to any one of claims 1 or 2, in which the transmitting module (110) comprises an HBC electrode (1102) for transmitting the command data (z) and the capacitive touch screen (1202 ) is adapted to act as a second electrode for receiving said control data (z), the first electrode (1102) and said capacitive touch screen (1202) being connected to the same ground (GND). Control device according to any one of claims 1 to 3, in which the capacitive touch screen (1202) is adapted to detect the presence of the user's body part before contact between said body part and said screen. (1202). Control method for controlling at least one parameter (P) among a plurality of parameters in a motor vehicle (10), said control method comprising:
- a step of transmission (E4, E5) of command data (z) between a transmission module (110) and a capacitive touch screen (1202), said command data (z) being adapted to be transported by a part a body of a user of the motor vehicle (10), said part of the user's body being in contact with said screen (1202) at a point of contact;
- a step of determining (E6) the parameter (P) to be controlled according to the position of the contact point on the capacitive touch screen (1202);
- a control step (E8, E9) of the parameter (P) from the control data (z) if the user is authorized to control said parameter (P) in said motor vehicle (10). Control method according to claim 5, in which said method comprises a step of querying (E7, E10) an access rights management database (12013) to determine whether the user is authorized to control said parameter in the motor vehicle (10). Control method according to any one of claims 5 or 6, in which the part of the user's body is in contact with the capacitive touch screen (1202) for a contact time greater than or equal to one second. Computer program product comprising program instructions usable by a control device (100) for controlling at least one parameter (P) among a plurality of parameters in a motor vehicle (10) according to any one of the claims 1 to 4, which when executed or interpreted by said control device trigger the implementation of a control method for controlling said at least parameter (P) according to any one of Claims 5 to 7 in the motor vehicle. Motor vehicle comprising a control device for controlling at least one parameter (P) among a plurality of parameters according to any one of Claims 1 to 4.