Method for operating a driver assistance system of a vehicle and driver assistance system

Abstract

The invention relates to a method for operating a driver assistance system (102) of a vehicle (100) in a support mode, wherein a driver demand (112) currently expressed by a driver (106) of the vehicle (100) via an angular position of a travel pedal (110) or an angular position of a hand throttle handle (110) of the vehicle (100) is converted into a power rating (114) of the vehicle (100) influencing a vehicle acceleration of the vehicle (100) depending on a current vehicle acceleration value (118) of the vehicle (100) and a target acceleration value (120) of a target vehicle (104) in order to support the driver (106) here in imitating a driving behavior of the target vehicle (104). The invention also relates to a driver assistance system, a computer program and a machine-readable storage medium.

Description

TECHNICAL FIELD

[0001] The invention relates to a method for operating a driver assistance system of a vehicle in a support mode and to a corresponding driver assistance system with such a support mode. BACKGROUND

[0002] In a vehicle with a distance regulator, a set distance is adjusted to a situation-dependent target distance to a vehicle driving in front. When driving close to the vehicle driving in front, the distance regulator reduces the motor power of the vehicle in accordance with a driver's wishes of the vehicle driver picked up on the driving pedal of the vehicle until the vehicle follows the vehicle driving in front at its speed behind it at the target distance. The distance regulator can be deactivated, for example, by depressing the driving pedal, for example, in order to overtake the vehicle driving in front. SUMMARY

[0003] Against this background, a method for operating a driver assistance system of a vehicle in a support mode and a corresponding driver assistance system are proposed with the solution presented here, and finally a corresponding computer program product and a machine-readable storage medium are proposed. Advantageous extensions and refinements of the solution presented here result from the description and are described in the preferred embodiments.

[0004] The embodiments of the invention can support the driver of the vehicle here in an advantageous manner in imitating the driving behavior of a target vehicle driving in front, for example. When the driver, for example, gives the accelerator too little in order to accelerate out of a curve similarly to the target vehicle, the motor management of the vehicle can be intervened in particular by the solution presented here in order to approximately achieve the acceleration of the target vehicle.

[0005] Within the scope of the present application and the invention, reference is made to a driver's command or a driver's wish input, in particular for predefining a vehicle acceleration value, or to a driver assistance system which is operated by means of the angular position of the driving pedal. Here, such a device for inputting a driver's command can be a driving pedal which is operated by the driver's foot in the case of a two-track vehicle. Alternatively, such an input device can also be retrofitted, which fulfills the same task as the driving pedal. This is, for example, a device for hand throttle operation, as it is provided as a special accessory by most vehicle manufacturers, or a hand throttle rotary lever or speed rotary handle, as it is used in single-track vehicles, such as scooters, mopeds, or in motorized three- or four-wheeled vehicles (Trikes).

[0006] Such alternatives are obvious and can be implemented by the person skilled in the art without inventive effort.

[0007] Furthermore, within the scope of the present application, only the concept "driving pedal" is used for reasons of easier understanding and simpler readability, however, all other alternatives which are obvious to the person skilled in the art are therefore also included, for example a driver assistance system which is controlled by a hand throttle handle or a manually rotating handle or a speed rotating handle.

[0008] The present application proposes a method for operating a driver assistance system of a vehicle in a support mode, wherein a driver's desire which is currently expressed by an angular position of a driving pedal of the vehicle is converted into a vehicle power rating which influences a vehicle acceleration of the vehicle depending on a current vehicle acceleration value of the vehicle and a target acceleration value of a target vehicle, in order to support the driver here in imitating a driving behavior of the target vehicle.

[0009] The idea of the embodiments of the present application can be considered to be based, inter alia, on the ideas and recognitions described below.

[0010] The driver assistance system of the vehicle can comprise different functional modules. A functional module can be a distance regulator. Another functional module can be a support mode.

[0011] The drive train of the vehicle can be controlled by a power rating. The power rating can be essentially set by a driver's desire. The driver's desire can be read by a driving pedal of the vehicle. The power rating can be influenced by the driver assistance system.

[0012] The distance regulator can be controlled by the driving pedal, inter alia. Here, a regulated distance to a vehicle driving in front can be influenced by an angular position and / or an angular velocity of the driving pedal. The angular position and / or the angular velocity can represent the driver's desire.

[0013] The distance regulator converts the driver's desire into a power rating depending on a current distance. Here, a change in the driver's desire is converted into a change in the power rating depending on the current distance. The closer the current distance is to a distance target value, the smaller the change in the power rating.

[0014] If the other vehicle brakes and thus does not comply with the distance target value, the power rating is reduced and, if necessary, a brake system of the own vehicle is controlled in order to also brake the own vehicle.

[0015] In the support mode, the driver assistance system can support the driver to drive as similar to the target vehicle as possible. The target vehicle can be driven by a trainer, for example. The driver can be referred to as a trainee or pupil. In the support mode, the distance transformation can be carried out to the acceleration of the target vehicle as a target value. The acceleration of the target vehicle can be referred to as target acceleration. The target acceleration can be represented by a target acceleration value. The support mode can be activated by an instruction of the driver. The support mode can be activated by pressing a button, for example. In the case that the support mode has been activated, the power demand value can be intervened such that the acceleration of the own vehicle follows the target acceleration of the target vehicle. The acceleration of the vehicle can be referred to as vehicle acceleration. The vehicle acceleration can be represented by a vehicle acceleration value. However, a minimum distance with respect to the speed can also be observed to avoid a touch between the vehicles. In other words, the distance regulator can also be active in the background and adjust the distance target value to the minimum distance in the case that the support mode has been activated.

[0016] If the vehicle acceleration value is smaller than the target acceleration value, the power demand value can be increased. If the vehicle acceleration value is greater than the target acceleration value, the power demand value can be decreased. The power demand value can be adjusted using the target acceleration value.

[0017] The target vehicle can be sensed by at least one sensor of the vehicle which is oriented in the driving direction. The target acceleration value can be determined using sensor data of the sensor. For example, a radar sensor of the own vehicle can sense the target vehicle. Likewise, the own vehicle can have a lidar sensor or a camera for sensing the target vehicle. From the sensor data, a target trajectory of the target vehicle can be calculated.

[0018] Alternatively, the target acceleration value can be derived from a target trajectory of the target vehicle which is read via an interface to a data transmission system. The target trajectory can reflect the driving behavior of the target vehicle. As the target trajectory, a plurality of coordinate points can be stored. Each coordinate point is associated with a time point at which the target vehicle passed the coordinate point. From the target trajectory, a target speed value and a target acceleration value of the target vehicle can be derived. The target acceleration value can also be stored directly with each coordinate point. The target trajectory can be recorded in the target vehicle using a navigation system, for example, and transmitted to the data transmission system. The target trajectory can also be generated manually. Subsequently, the target vehicle can be displayed for the driver in front of the vehicle, for example, by a head-up system. By remote transmission of the target trajectory, a plurality of vehicles can follow the same target trajectory on the same route one after the other.

[0019] If the current vehicle position of the own vehicle substantially corresponds to the target position, the target acceleration value sensed at the target position of the target vehicle can be used in order to translate the driver's desire into a power demand value. The target position can be a coordinate point on the target trajectory. The corresponding target acceleration value can be used when the vehicle passes the target position. The target position can be, for example, a braking point before a curve or an acceleration point at the end of the curve. For an inexperienced driver, the braking point can be located exceptionally far before the curve. The target acceleration value can drop sharply at this braking point and can also become negative. The acceleration point can be arranged at the inflection point of the curve. For an inexperienced driver, the acceleration point can be located exceptionally far before the curve exit. The target acceleration value can rise sharply at this acceleration point. The target vehicle can have already passed the braking point and the acceleration point at the point in time at which the vehicle passes and has braked or accelerated there. Thus, the safety distance between the vehicles can be adhered to.

[0020] If the vehicle acceleration value is greater than the target acceleration value by more than a braking tolerance range, the braking system of the vehicle can be actuated. When the braking system is actuated, the power demand value can be reduced to zero. The braking torque to be achieved by the braking system can be predefined by a braking torque demand value. By actuating the braking system, the driver can be supported, for example, when braking around a curve. The braking tolerance range can be selectable.

[0021] If the vehicle acceleration value deviates from the target acceleration value by more than a tolerance range, the power demand value can be changed. The vehicle acceleration value can have a slight positive or negative deviation relative to the target acceleration value. By means of the tolerance range, the driver can have a natural driving experience. The tolerance range can be selectable.

[0022] The power demand value can be changed stepwise depending on the difference between the vehicle acceleration value and the target acceleration value. The greater the difference, the greater the change in the power demand value can be. The power demand value can be changed in preconfigured steps, so that the intervention in the support mode is perceptible to the driver. When jumping from one step to the next, the vehicle can experience a perceptible jerk. The height of the steps can be selected by preconfiguration.

[0023] If the driver's desire is greater than a minimum threshold value, the power demand value can be changed. If the driver releases the accelerator and apparently no longer wants or is able to follow the target vehicle, the intervention by the support mode can be stopped and / or the support mode can be automatically deactivated. The minimum threshold value can be proportional to the target acceleration value. Another mode of the driver assistance system can be automatically activated when the support mode is deactivated. For example, a distance regulator can be automatically activated. The minimum threshold value can be selectable.

[0024] The power rating can be changed in consideration of the vehicle inertia of the vehicle. The vehicle inertia can consist of the response characteristic of the vehicle drive train and the mass inertia of the vehicle. The target acceleration value can be monitored in a pre-known manner in order to identify changes in the target acceleration value in advance. The power rating can be matched slightly in advance in consideration of the vehicle inertia, so that the output power of the vehicle can be matched when the vehicle reaches the location of the change in the target acceleration value.

[0025] The method can be implemented, for example, in software or hardware or in a hybrid form composed of software and hardware, for example in a controller.

[0026] The solution presented here also provides a driver assistance system which is configured to carry out, execute or convert the steps of the variant of the method presented here.

[0027] The driver assistance system can be an electrical appliance which has at least one computing unit for processing signals or data, at least one storage unit for storing signals or data and at least one interface and / or communication interface for reading or outputting data embedded in a communication protocol. The computing unit can be, for example, a signal processor, a so-called system ASIC or a microcontroller, for processing sensor signals and outputting data signals from the sensor signals. The storage unit can be, for example, a flash memory, an EPROM or a magnetic storage unit. The interface can be configured as a sensor interface for reading sensor signals from sensors and / or as an actuator interface for outputting data signals and / or control signals to actuators. The communication interface can be configured for reading or outputting data wirelessly and / or by wire. The interface can also be a software module which exists, for example, on a microcontroller alongside other software modules.

[0028] A computer program product or computer program with program code which can be stored on a machine-readable carrier or storage medium, such as a semiconductor memory, a hard disk memory or an optical memory, and which serves, in particular when the program product or program is implemented on a computer or device, to execute, convert and / or execute the steps of the method according to one of the preceding embodiments is also advantageous.

[0029] It should be noted that some of the possible features and advantages of the present application are described herein with reference to different embodiments. The person skilled in the art will recognize that the features of the driver assistance system and the method can be combined, matched or replaced in a suitable manner in order to realize further embodiments of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0030] In the following, embodiments of the present application are described with reference to the accompanying drawings, in which the drawings and the description are not to be considered limiting on the application.

[0031] It should be noted that some of the possible features and advantages of the present application are described herein with reference to different embodiments. The person skilled in the art will recognize that the features of the driver assistance system and the method can be combined, matched or replaced in a suitable manner in order to realize further embodiments of the present application.Figure 1 A diagram of a vehicle with a driver assistance system according to an embodiment is shown.

[0032] The drawing is merely schematic and not to scale. In the drawing, the same or similar reference signs denote the same or similar features. DETAILED DESCRIPTION

[0033] Figure 1 A diagram of a vehicle 100 with a driver assistance system 102 according to an embodiment is shown. Here, the vehicle 100 is driven on a closed training ground behind a target vehicle 104 controlled by a trainer. The driver 106 of the vehicle tries to imitate the driving behavior of the target vehicle 104 as precisely as possible.

[0034] The driver assistance system 102 has a support mode. The driver 106 activates the support mode by means of an operating element 108 of the vehicle 100 in order to be supported in imitating the driving behavior. The operating element 108 can be, for example, a toggle surface on the steering wheel of the vehicle 100.

[0035] In the case where the support mode has been activated, the driver's desire 112 sensed by the driver 106 by means of the angle position of the drive pedal 110 of the vehicle 100 is not directly translated into a power rating 114 for the drive train 116 of the vehicle 100. The driver assistance system 102 reads the driver's desire 112 in the support mode, compares a vehicle acceleration value 118 representing the current acceleration of the vehicle 100 with a target acceleration value 120 representing the acceleration of the target vehicle 104 and translates the driver's desire 112 into the power rating 114 using the comparison result. Here, the driver's desire 112 can be directly translated into the power rating 114 as long as the vehicle acceleration value 118 lies within a tolerance range around the target acceleration value 120.

[0036] When the vehicle acceleration value 118 is smaller than the target acceleration value 120 by more than the tolerance range, the driver 106 gives the accelerator too little and the driver's desire 112 is too small in order to approximately reach the target acceleration value 120. The power rating 114 is therefore increased.

[0037] When the vehicle acceleration value 118 is greater than the target acceleration value 120 by more than the tolerance range, the driver 106 gives the accelerator too much and the driver expectation 112 is too great. Therefore, the power rating 114 is reduced. When the vehicle acceleration value 118 is too great so that the vehicle 100 cannot be braked sufficiently by merely reducing the power value 114, in one embodiment the brake system 122 of the vehicle 100 is actuated. The brake system 122 can be actuated when the vehicle acceleration value 118 is greater than the target acceleration value 120 by more than the brake tolerance range. The brake system 122 can also be actuated when the distance to the target vehicle 104 is less than the minimum distance.

[0038] Here, the power rating 114 can be increased and / or reduced stepwise so that the driver 106 perceives the intervention of the support mode. The more the vehicle acceleration value 118 deviates from the target acceleration value 120, the greater the steps can be.

[0039] In one embodiment, the target vehicle 104 actually exists and is sensed by at least one sensor 124 of the vehicle 100. As long as the target vehicle 104 is arranged within a sensing range 126 of the sensor 124, the target acceleration value 120 can be derived from sensor data of the sensor 124. When the target vehicle 104 drives outside the sensing range 126 and thus can no longer be sensed, or when the target vehicle 104 only virtually or as a simulation exists, the target acceleration value 120 can be derived from a target trajectory 128 of the target vehicle 104. The target trajectory 128 can be recorded by the target vehicle 104 and provided, for example, via a data transmission system 130. If no real target vehicle 104 exists at all, the target trajectory 128 can be called up, for example, from a data store of the vehicle 100.

[0040] From the target trajectory 128, a target acceleration value 120 can be derived substantially for each target position 132 of the target vehicle 104. Since the vehicle 100 drives at a distance behind the target vehicle 104, in one embodiment the target acceleration value 120 is used when a current vehicle position 134 of the vehicle 100 substantially corresponds to a target position 132. In particular, the target acceleration value 120 can be used when the current vehicle position 134 lies on a line that runs through the target position 132 and is perpendicular to the target trajectory 128.

[0041] In one embodiment, the support mode is automatically deactivated when the driver demand 112 is less than a minimum threshold. Thus, the driver 106 can switch off the support mode by clearly releasing the accelerator. The support mode is switched on again only after reactivation by the operating element 108. The support mode can also be switched off at any time by the operating element 108. The minimum threshold can be related to the target acceleration value 120. For example, the minimum threshold can be a fixed proportion of the target acceleration value 120.

[0042] In other words, in the case of a performance assistant (Performance) as an additional feature for a driver assistance function (DDA) for ensuring the distance. Figure 1 In other words, in the case of a performance assistant (Performance) as an additional feature for a driver assistance function (DDA) for ensuring the distance.

[0043] Different driver assistance systems are currently present in vehicles, such as adaptive cruise control (ACC) and highway assistance (HWA), which provide the driver with greater comfort and more safety. In addition, other assistance systems obtain safety by means of distance warning and emergency braking intervention.

[0044] In the driver-oriented assistance function "dynamic distance assistance" (DDA), the driver is largely relieved of the burden of pedal braking, rear-end collisions are prevented and the accelerator pedal or, in single-track vehicles, the travel rotary handle is still left to the driver.

[0045] In the case of ACC as a self-acceleration function, the limit acceleration value and the acceleration build-up value (Aufbauwert) and the deactivation of the function in the event of actuation of the brake pedal for reasons of functional safety. By leaving the accelerator pedal to the driver in the case of DDA, the following possibilities are obtained: the power of a sports vehicle is fully utilized and the function can also be made effective after actuation of the brake pedal.

[0046] In the solution presented here, the DDA is further developed as a ring road feature for driving events and driving training. The idea is that the participants of the driving event follow a professional driver (English: Follow-the-instructor). Here, the professional driver can design the driving style and the ring driving time (Rundenzeit) for the abilities and levels of the trainees on the basis of his experience. He can also consciously shift the focus variably between ring driving time optimization and driving pleasure.

[0047] Thus, in addition to the protective aspect of the DDA, performance assistance can also be provided in the following-the-leader event in the driving event on a circular road section. The DDA has already ensured a safe distance, and by another support the acceleration characteristic can also be optimized step by step. If the trained driver does not follow the professional driver, for example, not fast enough through a too small gas pedal value when accelerating out of a curve, the stepwise adjustable acceleration overshoot can be set The driver is supported here in following the instructor.

[0048] Here, by means of the performance assistance as a supplement to the DDA, it is ensured that the adjustable maximum distance to the preceding driving instructor is not exceeded and that a determined speed difference is not exceeded.

[0049] If the driver requires a determined acceleration that is greater than the adjustable threshold value, the determined acceleration is compared with the acceleration required in order not to exceed the determined distance to the instructor and the determined speed difference. Here, the desired distance and speed difference are related, inter alia, to the speed and acceleration of the instructor and the radius of the curve.

[0050] By dispensing with the use of an additional operating element (for example on the steering column switch) after activation, the focus remains on the driving road section. This differentiates the present solution, inter alia, from hitherto known solutions, for example the lock-to-target.

[0051] There is only a general on and off possibility (for example by means of a button).

[0052] If a positive difference (a_required - a_demand > 0) results when comparing the acceleration actually required by the driver via the gas pedal (a_demand) with the necessary acceleration for following (a_required), this positive difference can be reduced.

[0053] Adjustable in different levels / modes is that the difference (a_demand - a_required) is added to the actually required acceleration (a_demand) with different factors and deviations (a_demand + (a_required - a_demand) * f_Korrektur_x).

[0054] Likewise, a short-time acceleration jerk can indicate that the driver increases the acceleration. Here, the principle of action is similar to the braking jerk in an emergency braking system. Thus, the trained driver can be supported in following the professional instructor.

[0055] If the driver presses the brake, lifts the gas pedal or falls below a determined acceleration requirement, the acceleration overshoot is not allowed, so that the trained driver can at any time and as quickly as possible prohibit an undesired overshoot.

[0056] Additionally, a generally applicable shutdown of the performance assistance can be realized by a button. Thus, an undesired acceleration overshoot can be avoided in the case of too great a distance from the trainer.

[0057] If the trained driver is below the determined distance or he has established a too high positive speed difference, so that his acceleration request (a demand) has to be reduced, the DDA takes over the control and limits a demand to a allowed, wherein a allowed can also request a deceleration.

[0058] The driving pleasure can be further improved by this performance assistance supplement and the transition to the DDA. The trained driver can improve his own abilities by the targeted support of the trainer and the function. Since additional operating elements are dispensed with, the focus on the route and the trainer is never lost and the safety of the trained driver and the trainer is guaranteed in critical situations.

[0059] Finally, it is pointed out that the concepts like "having", "including" etc. do not exclude other elements or steps and that the concepts like "one" do not exclude a plurality. Reference signs in the claims shall not be construed as limiting the application.

Claims

1. A method for operating a driver assistance system (102) of a vehicle (100) in a support mode, wherein, An operator demand (112) currently expressed by an operator (106) of the vehicle (100) via an angular position of a travel pedal (110) or an angular position of a hand throttle handle of the vehicle (100) is converted into a power demand value (114) of the vehicle (100) influencing a vehicle acceleration of the vehicle (100) depending on a current vehicle acceleration value (118) of the vehicle (100) and a target acceleration value (120) of a target vehicle (104) in order to support the operator (106) here in imitating a driving behavior of the target vehicle (104), wherein an acceleration of the target vehicle (104) is referred to as target acceleration, which is represented by the target acceleration value (120), wherein the target vehicle (104) is sensed by at least one sensor (124) of the vehicle (100) oriented in the driving direction and the target acceleration value (120) is determined using sensor data of the sensor (124), wherein the target acceleration value (120) sensed at a target position (132) of the target vehicle (104) is used if a current vehicle position (134) of the vehicle (100) substantially corresponds to the target position (132), wherein the vehicle acceleration value (118) is compared to the target acceleration value (120) and the operator demand (112) is converted into the power demand value (114) based on the comparison result.

2. The method of claim 1, wherein, The target acceleration value (120) is derived from a target trajectory (128) of the target vehicle (104) read via an interface to a data transmission system (130).

3. The method of claim 1 or 2, wherein, If the vehicle acceleration value (118) is greater than the target acceleration value (120) by more than a braking tolerance range, a braking system (122) of the vehicle (100) is actuated.

4. The method of claim 1 or 2, wherein, If the vehicle acceleration value (118) deviates from the target acceleration value (120) by more than a tolerance range, the power demand value (114) is changed.

5. The method of claim 1 or 2, wherein, The power demand value (114) is changed stepwise depending on a difference between the vehicle acceleration value (118) and the target acceleration value (120).

6. The method of claim 1 or 2, wherein, If the operator demand (112) is greater than a minimum threshold value, the power demand value (114) is changed.

7. The method of claim 1 or 2, wherein, The power demand value (114) is changed taking into account a vehicle inertia of the vehicle (100).

8. An operator assistance system (102) configured for implementing, converting and / or actuating a method according to one of claims 1 to 7 in a corresponding device.

9. A computer program product comprising a computer program configured for implementing, converting and / or actuating a method according to one of claims 1 to 7.

10. A machine-readable storage medium having stored thereon a computer program configured for implementing, converting and / or actuating a method according to one of claims 1 to 7.

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