Method and control device for permitting driver to drive vehicle

Abstract

The present invention relates to a method (3) for allowing a driver to drive a vehicle (1) using a control device (2). In this method (3), if contact with the steering wheel (6) is detected, the current driver is identified. If the current driver is authorized to drive, permission to drive is granted for a certain period of time. The engine is started only if contact with the steering wheel (6) occurs during this period. The present invention also relates to a control device (2) for carrying out this method (3).

Description

[Technical Field]

[0001] The present invention relates to a method for allowing a driver to drive a vehicle by means of a control device according to the preamble of claim 1. The invention also relates to a control device for carrying out the method. [Background technology]

[0002] The detection of data via a vehicle steering wheel is already known in the prior art. U.S. Pat. No. 8,725,230 describes a vehicle steering wheel equipped with a sensor assembly capable of measuring biological parameters of a vehicle driver. German Patent Application Publication No. 102020005758 describes a method for allowing a driver to drive a vehicle. The driver is authorized after contacting the steering wheel of the vehicle, which then starts a timer for a predetermined period of time. If the driver confirms his / her request to drive within the predetermined period of time, the vehicle starts. The driver can confirm his / her request to drive, for example, by operating the brake pedal and / or gear selector lever of the vehicle. Therefore, the vehicle must be equipped with a system for detecting and evaluating signals from the brake pedal and / or gear selector lever of the vehicle. This results in additional costs and additional control effort.

[0003] U.S. Patent No. 6,898,299 discloses a method and apparatus for authenticating a particular person, where the unique internal electrical, magnetic, or acoustic properties of different body parts of the person can be identified, based on which a current biometric signature of the person can be generated, which can then be used to identify the person.

[0004] DE 10 2017 211 545 A1 discloses a device and a method for determining whether a driver has released their hands from the steering wheel, in which a reference torque signal and a measurement torque signal present at the time of a reference oscillation of the steering wheel are measured and evaluated.

[0005] German Patent Application No. 102007005627 discloses a system for providing vehicle occupant service information, which can detect biological characteristics of the user. Based on the biological characteristics, the system can assist the user in using the vehicle or entertain the user. These characteristics can be stored in the system and can be called up.

[0006] DE 112020003270T5 discloses a device and a method for detecting the position of a driver's hands on a steering wheel, whereby two independent impedance measurements are performed by means of two electrodes, from which the position of the driver's hands is calculated or determined. Summary of the Invention [Problem to be solved by the invention]

[0007] It is therefore an object of the present invention to provide an improved, or at least an alternative, embodiment to the standard type of method which overcomes the above-mentioned drawbacks. It is also an object of the present invention to provide a control assembly for carrying out this method. [Means for solving the problem]

[0008] This object is achieved according to the invention by the subject matter of the independent claims. Advantageous embodiments are the subject matter of the dependent claims.

[0009] The invention is based on the general idea of ​​controlling the start-stop function of a vehicle by contact with the steering wheel.

[0010] The method of the present invention is designed to allow a driver to drive a vehicle using a control device. In this method, the control device identifies the current driver when it confirms that the current driver has made contact with the steering wheel of the vehicle. If the control device identifies the current driver as a legitimate driver, it grants permission to drive for a predefined period of time. Next, the control device starts the vehicle engine if it confirms that the legitimate driver has made contact with the steering wheel of the vehicle within the predetermined period of time. If the control device does not confirm that the legitimate driver has made contact with the steering wheel of the vehicle within the predetermined period of time, it does not start the vehicle engine.

[0011] In the present invention, the terms "authorized driver" and "current driver" are distinguished from one another, as well as "identified driver" and "invalid driver." An authorized driver is a "virtual" driver characterized by a user profile. The user profile is created and stored in advance, as will be explained in more detail below. A current driver is a driver who is currently holding the steering wheel of a vehicle. The current driver may or may not be authorized to drive. If the current driver is authorized to drive, the driver is referred to as an identified driver. If the current driver is not authorized to drive, the driver is referred to as an invalid driver.

[0012] This method allows direct access to the start-stop function of the vehicle. In this case, a validly identified driver can start the vehicle's engine with their hands on the steering wheel, but cannot start the engine with their hands off the steering wheel. Using the method according to the present invention, existing start-stop systems can be extended with convenient functions or largely replaced. Additionally, the vehicle starting process can be simplified as a result. Compared to conventional methods or conventional vehicles, the detection and evaluation of signals from the vehicle's brake pedal and / or gear selector lever can also be omitted, thereby reducing additional costs and control efforts.

[0013] After the vehicle is permitted to travel, the control device can also load the individual driver settings of the identified driver, which may include, for example, seat settings, mirror settings, driving dynamics, valet service, and / or driving space preparation.

[0014] If the control unit does not identify the current driver as a legitimate driver, the control unit can grant permission to drive only to a limited extent or not at all. A limited permission to drive can be granted, for example, if the vehicle is authorized for valet service. The permission to drive the vehicle is granted when the vehicle is stationary and before the start of the journey, so that an incorrect response by the driver does not lead to a safety-critical event. Furthermore, the control unit can also command security measures. Security measures can be implemented, for example, by an entry in an error memory, a so-called security event log, and / or by disabling the vehicle, and / or by contacting a security system, a so-called incident response system, and / or by acoustic and / or visual warnings inside and / or outside the vehicle.

[0015] To identify the current driver, the control device can pre-determine the impedance of the legitimate driver from the hands of the legitimate driver holding the steering wheel of the vehicle only once. Then, when identifying the current driver, the control device can determine the impedance of the current driver from the hands of the current driver holding the steering wheel of the vehicle. Subsequently, the control device can determine a deviation between the impedance of the current driver and the pre-determined impedance of the legitimate driver. If the deviation is within a predetermined tolerance range, the control device can identify the current driver as a legitimate driver. On the other hand, if the deviation is outside the predetermined tolerance range, the control device can identify the current driver as an unauthorized driver. The tolerance range can be pre-defined.

[0016] Of course, the controller may pre-identify the impedances of multiple legitimate drivers, and in that case, when identifying the current driver, the controller may look up the user profiles of all legitimate drivers until the current driver is identified as a legitimate driver or is not identified. The controller may look up the corresponding user profiles sequentially, or may begin identification using the user profile of the previous driver.

[0017] The impedance of human skin can be detected by methods known to those skilled in the art. To this end, the control device can have a measurement unit including a measurement circuit and a measurement surface. The measurement surface can be placed on the vehicle's steering wheel and electrically connected to the measurement circuit so that it can be held or touched by the driver. The measurement surface can be provided with two electrodes, and the measurement unit applies a current or voltage to these electrodes and detects a voltage or current response. The impedance of the driver's skin can be measured when the driver's hand is on the measurement surface. The measured impedance depends on the frequency of the applied current or voltage, which is typically between 1.22 kHz and 1 MHz. Needless to say, the impedance is what is known as electrochemical impedance.

[0018] Generally, a driver can steer a vehicle by placing their hands on the steering wheel, and by determining the impedance at the steering wheel, contact with the steering wheel can be recognized, the current driver can be identified, and the vehicle can be started, thereby simplifying the vehicle starting process.

[0019] When determining the impedance of the current driver and / or pre-determining the impedance of the legitimate driver, the control device may detect at least one ambient environment parameter and determine the impedance of the current driver and / or the pre-determined impedance of the legitimate driver by taking the at least one ambient environment parameter into consideration. For this purpose, an allowable range of impedance depending on the ambient environment may be defined. Since the impedance depends on the ambient environment parameter, incorrect identification of the current driver can be avoided. The ambient environment parameter may be humidity and / or temperature. A change in impedance due to humidity can be compensated for, for example, by a sweat pore model. A change in impedance due to temperature can be compensated for, for example, by the Arrhenius equation.

[0020] Advantageously, in order to keep the temperature of the electrodes, and therefore of the operator, as constant as possible, it is useful to integrate a temperature regulation element into the electrodes to ensure a uniform temperature (even over several measurement cycles). This can be both a cooling element and a heating element operating in the body temperature range of about 37°C.

[0021] The control device can parameterize the pre-determined impedance of a legitimate driver using a mathematical model to determine at least one parameter characteristic of the legitimate driver. Similarly, the control device can parameterize the impedance of a current driver using a mathematical model to determine at least one parameter characteristic of a current driver. The control device can then compare each parameter characteristic of the current driver with each parameter characteristic of a legitimate driver when determining a deviation between the impedances. In other words, when determining a deviation between the impedances, a deviation between the parameters sensed using the model is determined or calculated.

[0022] It is expedient to use the same model when identifying characteristic parameters. Each model represents the impedance of human skin through its characteristic parameters. Each characteristic parameter varies from person to person because it represents the characteristic properties of the skin. Therefore, these parameters can be used to identify humans. Models for parameterizing the impedance of human skin are already known to those skilled in the art and will not be further described here. For example, human skin can be represented using Tregear's model, Montague's model, or a CPE-based model. Furthermore, human skin can be approximated as a distribution and fractal representation of Debye relaxation. This model is often called a model of distribution of relaxation times. The parameterization itself can be performed, for example, using least squares fit, particle swarm optimization, or similar techniques.

[0023] The pre-determination of the impedance of the legitimate driver is performed in time before the identification of the current driver. The pre-determination of the impedance of the legitimate driver can be performed once and independently in time before the identification of the current driver. In other words, the impedance of the legitimate driver can be performed once, a few hours, days, or weeks before the initial identification of the current driver. The pre-determination of the impedance of the legitimate driver can basically be considered as a learning process of the control device. The pre-determination of the impedance of the legitimate driver can be performed, for example, when the control device starts operating or before the first journey. However, it is basically also conceivable that a new pre-determination of the impedance of the legitimate driver or a first pre-determination of the impedance of another legitimate driver can be performed later. The impedance pre-determination or learning process can be started manually at any time, for example, in another step of the method.

[0024] The control device can create a user profile of the authorized driver and store it in a non-volatile memory in the security module. The user profile can include at least a pre-determined impedance of the authorized driver and / or respective parameters specific to the authorized driver. The security module can be, for example, a specially protected component such as a so-called security IC, e.g., the NXP Phantom NCJ38A0HN. The security module can also be a hardware security module of a microcontroller, e.g., an Infineon Aurix. The security module can in particular be an integrated and inaccessible control device of an electronic ignition lock. By storing data in a non-volatile memory in the security module, the user profile can be protected from misuse, such as unauthorized deletion.

[0025] The control device can create a personal identification number for the created user profile and store the personal identification number together with the user profile in non-volatile memory in the security module. The control device can then allow changes to the stored user profile only after the correct personal identification number has been entered. The personal identification number or PIN can protect the user profile from misuse, such as unauthorized deletion. The personal identification number can be queried or entered, for example, via the monitor of the control device or a mobile terminal. The personal identification number is required, in particular, when creating and deleting a user profile.

[0026] The control device can perform the determination of the current driver's impedance using the measurement unit as already described above. The control device can determine the deviation and compare it with a predetermined tolerance in a security module physically separated from the measurement unit. The security module can be designed as described above.

[0027] To enhance the safety of the method, the control device can determine the impedance of the identification circuit together with or separately from the impedance of the current driver. In that case, the control device can compare the deviation between the currently determined impedance of the identification circuit and a previously determined impedance of the identification circuit. If the deviation is within a predetermined tolerance, the identification circuit is deemed not to have been tampered with and permission to drive is granted. If the deviation is outside the predetermined tolerance, the identification circuit is deemed to have been tampered with and permission to drive is granted only to a limited extent or not at all.

[0028] The identification circuit may be part of a measuring unit of the security device and may be measured alone or in series with the measuring surface. For this purpose, the measuring unit may have a correspondingly connected switch. In one position of the switch, the measuring surface at the steering wheel of the vehicle and the identification circuit can be connected in series with each other and with the measuring circuit, while in the other position of the switch, only the identification circuit can be connected in series with the measuring circuit. The switch may be a transistor or MOSFET or a relay or another electrical switch. A relay may be particularly suitable for this, since the change in impedance detected by the measuring circuit at the measuring surface is small.

[0029] The impedance of the identification circuit can be parameterized using a mathematical model, e.g., a distribution of Debye relaxation, and the identification characteristics of the identification circuit can be determined from the model. This takes advantage of the fact that identical circuits, or circuits with identical elements, can be clearly distinguished from one another by having different identification characteristics. The identification circuit can have at least two elements, e.g., a coil and / or an ohmic resistor and / or a capacitor, that can be arbitrarily connected to one another. In particular, the identification circuit can have an ohmic resistor and a capacitor, which together can represent the distribution of Debye relaxation and are particularly well distinguishable. These elements can be selected, in particular, so that the distribution of Debye relaxation of these elements is characterized at frequencies 2-3 decades (20-30) before and / or after the typical value of the current driver's impedance.

[0030] The impedance or unique identification characteristic of the identification circuit may even be pre-specified at the factory and stored in non-volatile memory within the control device, for example the security module mentioned above.

[0031] According to the invention, the identification circuit is made physically difficult to access, for example by potting. According to the invention, the identification circuit is integrated into the steering wheel of the vehicle. In that case, according to the invention, both manipulation of the identification circuit and replacement of the steering wheel equipped with the identification circuit are recognized by the identification circuit.

[0032] According to the present invention, after permission to drive is granted, the control device continuously identifies the impedance of the driver identified as legitimate while the vehicle is driving, and then the user profile of the legitimate driver can be continuously adjusted according to the identified impedance, thereby taking into account changes in the legitimate driver's impedance over time and improving the robustness of the identification.

[0033] The invention also relates to a control device for a vehicle, the control device being designed to carry out the above-mentioned method. The control device may have a measurement unit for determining the impedance. The measurement unit may have a measurement circuit and a measurement surface. The measurement unit may further have an identification circuit and an electric switch. The switch may be switchable so that the measurement surface and the identification circuit are connected in series with each other and with the measurement circuit, or so that only the identification circuit is connected in series with the measurement circuit. The control device may have a security module. To avoid repetition, reference is made here to the above description.

[0034] Other important features and advantages of the invention emerge from the dependent claims, the drawings and the associated description of the drawings based on the drawings.

[0035] It goes without saying that the features mentioned above and those further described below can be used not only in the combinations shown, but also in other combinations or alone, without departing from the scope of the invention.

[0036] Preferred exemplary embodiments of the present invention are illustrated in the drawings and described in more detail below, where like reference numbers indicate identical or similar or functionally identical components.

[0037] Here, the following is generally described in each of the drawings: [Brief explanation of the drawings]

[0038] [Figure 1] 1 is a schematic diagram of a vehicle equipped with a control device according to the present invention. [Figure 2] FIG. 2 is a schematic circuit diagram of a measurement unit of the control device according to the present invention. [Figure 3] FIG. 2 is a schematic diagram of the learning process in the method according to the invention. [Figure 4] 1 is a schematic general diagram of the method according to the invention; FIG.

[0039] FIG. 1 shows a diagram of a vehicle 1 equipped with a control device 2 according to the invention. The control device 2 is designed to carry out a method 3 according to the invention, for allowing the driver to drive the vehicle 1. Method 3 will be explained in more detail below with the aid of FIGS. 3 and 4. The control device 2 comprises a measurement unit 4 having a measurement surface 5 arranged on the steering wheel 6 of the vehicle 1. When the driver's hand is on the measurement surface 5 of the measurement unit, the measurement unit 4 can confirm contact with the steering wheel 6 and detect the driver's impedance. The measurement unit 4 will be explained in more detail below with the aid of FIG. 2. The control device 2 further comprises a security module 7 that is difficult to access and secure against tampering. The security module 7 is designed in particular to store and process security-relevant data in accordance with method 3.

[0040] 2 shows a circuit diagram of the measuring unit 4 of the control device 2 according to the invention. As already mentioned above, the measuring unit 4 comprises a measuring surface 5 for determining the driver's impedance. Furthermore, the measuring unit 4 comprises a measuring circuit 8 and an identification circuit 9. In addition, the measuring unit 4 is provided with an electric switch 10, which may be, for example, a transistor or a MOSFET or a relay or another electric switch. In position A, the switch 10 connects the measuring surface 5, the measuring circuit 8 and the identification circuit 9 in series with one another. In position B, the switch 10 connects the measuring circuit 8 and the identification circuit 9 in series with one another. In this case, the measuring surface 5 remains disconnected.

[0041] In the identification circuit 9, multiple elements, such as ohmic resistors and / or coils and / or capacitors, can be optionally connected to each other. This allows the identification circuit 9 to have unique identification characteristics 11a, 11b, and 11c and to be uniquely identified. The identification characteristics 11a, 11b, and 11c can be determined from the impedance of the identification circuit 9 using a model, for example, using the distribution of Debye relaxation. The identification circuit 9 is formed, for example, potted, making it difficult to access from the outside.

[0042] FIG. 3 shows a diagram of the pre-determination of the impedance of an authorized driver or the learning process of the control device 2 in the method 3 according to the present invention. In step A, the learning process is initiated. In step B, the impedance F of the authorized driver is measured by the measurement unit 4. In addition, ambient environmental parameters, such as humidity and temperature, can be detected, and their influence on the measured impedance F of the authorized driver can be calculated. In step C, the measured impedance F of the authorized driver is parameterized in a mathematical model, and at least one parameter specific to the authorized driver is determined. In step D, a user profile is created for the authorized driver, and a personal identification number is created for the user profile. In step E, the user profile with the impedance F or with each parameter specific to the impedance F and the personal identification number are stored in a non-volatile memory in the security module 7 of the control device 2. The user profile can only be changed after the correct identification number has been entered.

[0043] FIG. 4 shows a general diagram of method 3 according to the present invention. In step G, method 3 is initiated, for example, by placing hands on the steering wheel 6 of the vehicle 1. In step H, the current driver's impedance is measured by the measurement unit 4. Additionally, ambient environmental parameters, such as humidity and temperature, can be detected, and their influence on the current driver's measured impedance can be considered. In step J, the current driver's measured impedance is compared with a pre-determined impedance F of a legitimate driver. If the deviation between the current driver's measured impedance and the pre-determined impedance F of a legitimate driver is outside an acceptable range, in step K, the current driver is recognized as an unauthorized driver and is granted permission to drive only to a limited extent or not at all. If the deviation between the current driver's measured impedance and the pre-determined impedance F of a legitimate driver is within an acceptable range, in step L, the current driver is recognized as an authorized driver and is granted permission to drive. In step J, multiple user profiles can also be checked sequentially, or the current driver's measured impedance can be compared with a pre-determined impedance F from multiple pre-stored user profiles. Subsequently, in step M, the control device 2 can load individual driver settings for the driver identified as valid, such as seat settings and / or mirror settings and / or driving dynamics and / or valet service and / or driving space preparation.

[0044] In Method 3, the learning process or pre-identification of the valid driver's impedance in steps A to E of Figure 3 occurs before the other steps G to L of Figure 4. In other words, in order to perform steps G to L of Figure 4, at least one user profile created in steps A to E of Figure 3 must be present in the security module 7. However, other user profiles can be created and stored in the security module 7 at any other time. [Prior art documents] [Patent documents]

[0045] [Patent Document 1] U.S. Patent No. 8,725,230 [Patent Document 2] German Patent Application Publication No. 102020005758 [Patent Document 3] U.S. Patent No. 6,898,299 [Patent Document 4] German Patent Application Publication No. 102017211545 [Patent Document 5] German Patent Application Publication No. 102007005627 [Patent Document 6] German Patent Application Publication No. 112020003270T5

Claims

1. A method (3) for allowing a driver to drive a vehicle (1) using a control device (2), comprising: - the control device (2) identifies the current driver when it detects contact with the steering wheel (6) of the vehicle (1) by the current driver; - if the control device (2) identifies the current driver as a legitimate driver, it grants permission to drive for a predefined period of time; - the control device (2) starts the engine of the vehicle (1) if it is confirmed within the predetermined period that the driver who has been identified as valid has touched the steering wheel (6) of the vehicle (1); - the control device (2) does not start the engine of the vehicle (1) if it is not confirmed within the predetermined period that the driver who has been identified as valid has touched the steering wheel (6) of the vehicle (1), - after the permission to travel, the control device (2) continuously determines the impedance of the driver identified as legitimate during the driving operation of the vehicle (1) and continuously adjusts the user profile of the legitimate driver according to the determined impedance; The security device (2) uses an identification circuit (9) integrated into the steering wheel (6) of the vehicle (1) in a physically difficult to access location to recognize tampering with the identification circuit (9) and / or replacement of the steering wheel (6) with the identification circuit (9). A method characterized by:

2. - the control device (2) predetermines once and for all the impedance (F) of the authorized driver from the hands of the authorized driver holding the steering wheel (6) of the vehicle (1); - when identifying the current driver, the control device (2) determines the impedance of the current driver from the current driver's hands gripping the steering wheel (6) of the vehicle (1); - the control device (2) determines the deviation between the impedance of the current driver and the pre-specified impedance (F) of the correct driver; - the control device (2) identifies the current driver as the legitimate driver if the deviation is within a predetermined tolerance; The control device (2) identifies the current driver as an unauthorized driver if the deviation is outside the predetermined tolerance range.

2. The method of claim 1.

3. When determining the impedance of the current driver and / or when pre-determining the impedance (F) of the legitimate driver, the control device (2) detects at least one ambient environment parameter and determines the impedance of the current driver and / or the pre-determined impedance (F) of the legitimate driver taking the at least one ambient environment parameter into consideration.

3. The method according to claim 2.

4. - the control device (2) determines at least one parameter specific to the legitimate driver by parameterizing the pre-determined impedance (F) of the legitimate driver using a mathematical model; - the control device (2) parameterizes the impedance of the current driver using the mathematical model to identify at least one parameter specific to the current driver; - when determining the deviation between the impedances, the control device (2) compares the respective parameters characteristic of the current driver with the respective parameters characteristic of the legitimate driver with each other; 4. The method according to claim 2 or 3.

5. The control device (2) creates a user profile of the authorized driver and stores it in a non-volatile memory in a security module (7), the user profile including at least the pre-specified impedance (F) of the authorized driver and / or each of the parameters specific to the authorized driver. The method according to any one of claims 2 to 4, characterized in that

6. - the control device (2) creates a personal identification number for the created user profile and stores the personal identification number together with the user profile in a non-volatile memory in the security module (7); - the control device (2) allows modification of the stored user profile only after entering a correct personal identification number 6. The method according to claim 5.

7. - the control device (2) determines the impedance of the current driver using a measurement unit (4); The control device (2) determines the deviation in a security module (7) physically separated from the measurement unit (4) and compares the deviation with the predetermined tolerance range. The method according to any one of claims 2 to 6, characterized in that

8. - the control device (2) determines the impedance of the identification circuit (9) together with or separately from the impedance of the current driver; - the control device (2) determines the deviation between the currently determined impedance of the discrimination circuit (9) and a pre-determined impedance of the discrimination circuit (9); - the control device (2) considers that the identification circuit (9) has not been tampered with and gives the permission to travel if the deviation is within a predetermined tolerance range; If the deviation is outside the predetermined tolerance range, the control device (2) considers that the identification circuit (9) has been tampered with and grants the permission to drive only to a limited extent or not at all. The method according to any one of claims 2 to 7, characterized in that

9. A control device (2) for a vehicle (1), The control device (2) is designed to carry out the method (3) according to any one of claims 1 to 8. A control device characterized by:

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