Method for operating a driver assistance system, processing device for controlling a driver assistance system, and motor vehicle having a driver assistance system

Abstract

A method (200) for operating a driver assistance system (115) comprises the steps of: capturing (205) information which indicates an imminent intervention of the driver assistance system (115) in the guidance of the motor vehicle (105); providing (215, 220) an advance warning directed to a driver (110) of the motor vehicle (105) before the intervention, the advance warning comprising a first and a second warning signal, the first warning signal being optically and / or acoustically and / or haptically output (215) and the second warning signal (220) comprising a kinesthetic jerk; and providing (235, 240) a main warning before the intervention, the main warning being subsequent to the advance warning, and the main warning comprising an acoustic warning signal and / or an optical warning signal.

Description

[0001] Method for operating a driver assistance system, processing device for controlling a driver assistance system and motor vehicle with a driver assistance system

[0002] The present invention relates to a method for operating a driver assistance system, a processing device for controlling a driver assistance system, and a motor vehicle with a driver assistance system. In particular, the invention relates to providing a warning to a driver of such a motor vehicle before the driver assistance system intervenes in the control of the motor vehicle.

[0003] A motor vehicle may include a driver assistance system that can actively intervene in the longitudinal and / or lateral control of the vehicle. For example, an automatic brake assist system can continuously scan the vehicle's surroundings for the presence of a hazardous situation. If such a situation is detected, a warning signal can be provided to give the driver the opportunity to resolve the hazardous situation, for example, by applying the brakes themselves or changing direction. If the driver does not resolve the hazardous situation in time, the vehicle can be automatically braked.

[0004] It has been suggested that such a warning signal could be provided by varying the vehicle's acceleration in the longitudinal direction. For example, DE 10 2014 214 386 A1 proposes informing a vehicle occupant of a predetermined event using a kinesthetic signal.

[0005] However, certain operations on board the motor vehicle may be so important that a single signal is not sufficient to safely inform a person.

[0006] An object underlying the present invention is therefore to provide an improved technology for providing a warning to a driver of a motor vehicle. The invention solves the problem by means of the subject matter of the independent claims. Subclaims specify preferred embodiments. According to a first aspect of the present invention, a method for operating a driver assistance system of a motor vehicle comprises the following steps: detecting information indicating an impending intervention of a driver assistance system in the control of the motor vehicle, such asan emergency braking intervention; providing a pre-warning directed to a driver of the motor vehicle prior to the intervention, wherein the pre-warning comprises a first and a second warning signal, wherein the first warning signal is output optically and / or acoustically and / or haptically and the second warning signal comprises a kinesthetic jolt; and providing a main warning prior to the intervention, which main warning follows the pre-warning in time, wherein the main warning comprises an acoustic and / or a visual warning signal.

[0007] Preferably, the first and second warning signals are issued at least partially simultaneously. Thus, the criticality of a transmitted warning can be increased by using at least two different warning channels. However, it is also possible for the second warning signal to be issued before the first warning signal (or vice versa).

[0008] Preferably, the first warning signal comprises an optical signal.

[0009] The main warning is preferably provided via at least two sensory perception channels, such as a visual and an acoustic channel. In other words, the main warning, like the advance warning, can comprise two or more warning signals, one of which is visual and one acoustic, for example.

[0010] By using two different sensory channels of the driver, it can be ensured that the warning reaches them. At the same time, a requirement for a warning signal on board the motor vehicle can be met, so that the method can also be used to deliver a safety-relevant warning signal. Such a requirement can consist of a law, regulation, guideline, or directive, for example from a legislature or within the framework of the NCAP (New Car Assessment Program). The warning can, for example, relate to an existing hazardous situation that can be defused after a predetermined time by activating a braking system. Preferably, the kinesthetic jerk comprises a temporary change in the longitudinal acceleration of the motor vehicle. In particular, when the driver controls the longitudinal movement of the motor vehicle, the jerk, as the second derivative of the speed, can be primarily felt by the driver.Another passenger may not even consciously perceive the slight variation, may consider it insignificant, or at least may not be disturbed by it.

[0011] It is further preferred that the kinesthetic jerk be sufficiently small and / or short that the speed of the motor vehicle is not perceptibly changed by the driver. Although the longitudinal jerk is inevitably associated with acceleration and thus with a change in the speed of the motor vehicle, elasticity or play in the drive train, for example, can leave the speed of the motor vehicle relatively unchanged. Due to its brevity and / or low intensity, the kinesthetic jerk can be reliably felt without significantly affecting the longitudinal control of the motor vehicle.

[0012] For example, the jerk can be generated as a kinesthetic signal as described in the applicant's German patent application DE 10 2014 214 386 A1

[0013] Preferably, the longitudinal acceleration of the motor vehicle is increased by the jerk to a predetermined intensity of, for example, 1 m / s 2 or less, in particular 0.8 m / s 2 or less. In principle, both a positive and a negative variation of the acceleration are conceivable; however, it is preferably a braking jerk, i.e. a (preferably temporary) negative variation of the acceleration. In other words, the kinesthetic jerk can be designed according to a preferred embodiment in such a way that it causes a deceleration of the vehicle, whereby the deceleration is not more than 1 m / s. 2 , in particular not more than 0.8 m / s 2In particular, the kinesthetic jerk can be performed in such a way that the maximum deceleration achieved is in the range of 0.7 m / s 2 up to 0.8 m / s 2 lies.

[0014] Furthermore, the kinesthetic jerk can be carried out in such a way that it has a duration in the range of 300 ms to 1500 ms, in particular in the range of 300 to 450 ms and particularly preferably in the range of 300 ms to 350 ms. Furthermore, it can be provided that the kinesthetic jerk is carried out in such a way that a temporal change in acceleration achieved thereby (ie at least at any time during the jerk) is greater than or equal to 10 m / s. 3 , preferably greater than or equal to 15 m / s 3 and particularly preferably greater than or equal to 20 m / s 3 is.

[0015] The above preferred durations and intensities of the jerk ensure, on the one hand, that (given a sufficiently large acceleration or deceleration gradient), the jerk is just long and fast enough to exceed the human perception threshold; on the other hand, a jerk with these parameters is still clearly distinguished from a true braking or acceleration jerk, which is accompanied by a significant influence on the vehicle's kinematics. Thus, it is possible for the jerk to have an (almost purely) informational character. This is desirable, since the vehicle's handling should be directly influenced as little as possible by the jerk.

[0016] The preferred jerk characteristics in terms of duration and intensity proposed here are based on the realization that the amplitude of a jerk, which represents a perceptibility threshold for human perception, can be reduced by a high gradient. In other words: If the acceleration gradient is high (in terms of magnitude, i.e., regardless of its sign), acceleration does not have to be that high for humans to perceive the jerk. If, on the other hand, the jerk were to build up slowly with a comparatively low gradient, it would have to reach a higher amplitude to be perceived. This would then, in some cases, lead to a range beyond a purely informational jerk and would have an undesirably strong influence on the vehicle kinematics.

[0017] Furthermore, in this context, use is made of the finding that a jolt with a short duration in the range of human reaction time or less does not cause a startle reaction via a kinesthetic perception channel (in contrast to, for example, acoustic perception, which has a shorter startle build-up time; this is evident, for example, in the fact that even a very short bang can produce a startle). Thus, by providing a jolt with a duration in the ranges mentioned above (e.g., 300 ms to 350 ms), it is possible to generate a signal that informs the driver but does not startle him.

[0018] Using an electric motor vehicle, such a quick and short information jerk, which just reaches the perception threshold but does not unnecessarily influence the vehicle kinematics, can be generated particularly well. The advantage over a conventional friction brake is that the electric motor requires little or no readjustment and exhibits fewer delays overall, so that even a very short jerk with a high initial acceleration gradient can be generated precisely and reproducibly. For example, by appropriately controlling the electric motor, a 300-350 ms short jerk with an amplitude of 0.7-0.8 m / s can be generated. 2 must not exceed to be perceived as an information jolt. The key to perceptibility is the comparatively high initial gradient.

[0019] It is further preferred that the longitudinal acceleration be modified relative to a driver-controlled command. For example, if the driver is accelerating the motor vehicle at a predetermined rate, the kinesthetic jerk can be induced as a difference to the controlled acceleration. This ensures that the longitudinal movement of the motor vehicle is fully controlled by the driver and can still be used to transmit the kinesthetic jerk.

[0020] To effect the kinesthetic jerk, the longitudinal acceleration can be varied along a predetermined curve. This curve can, for example, follow a rectangular, triangular, sawtooth, or sine wave. The curve can be determined in such a way that the signaling effect on the driver is sufficiently strong while simultaneously ensuring a temporary change in the vehicle's speed is sufficiently small.

[0021] Preferably, the temporal progression of the longitudinal acceleration is approximately needle-shaped or sawtooth-shaped, i.e., with comparatively high gradients of increase and / or decrease and without a pronounced plateau at a maximum (or minimum). In the case of a braking jolt, for example, there is initially a comparatively steep drop in acceleration to a local minimum, followed immediately (i.e., without a pronounced lingering period in the region of the minimum) by another steep rise, e.g., approximately to the initial value of the acceleration before the braking jolt.

[0022] It is particularly preferred that the driver's level of attention be determined. This can, for example, be done before the information about the impending intervention is acquired (e.g., continuously while driving) and / or only afterward.

[0023] According to one embodiment, it can then be provided that the advance warning with the second warning signal is only provided if it is determined that the driver is inattentive ("inattentive driver detected"). Otherwise, it can be provided, for example, that the advance warning only includes the first (preferably optical) warning signal, but not the kinesthetic second warning signal. In other words, if an inattentive driver is detected, an advance warning can be provided on two perception channels (including a kinesthetic channel), whereas otherwise an advance warning is provided, for example, only on one optical perception channel. Under certain circumstances, the two-channel advance warning can avoid the need to bring forward an already two-channel intensive main warning in the event of a detected inattentive driver (e.g.to meet certain NCAP requirements), which could be perceived as annoying by the driver, particularly with regard to possible false positive events.

[0024] As already explained, the kinesthetic jolt is issued to provide an advance warning. The advance warning has a longer prediction horizon than a main or acute warning and thus also a higher error rate. By using the kinesthetic jolt for the advance warning, a false warning in particular can be perceived as less disturbing. The main or acute warning, which follows the advance warning in time, can have a higher prediction probability, but also a shorter prediction horizon. The main warning can be provided to the driver in such a way that it is more insistent than the advance warning. For example, the main warning can be an intensive warning with a flashing visual display and an additional loud warning tone. It is also within the scope of the invention that a time for issuing the advance warning is determined depending on the specific level of attention of the driver.

[0025] For example, if the warning concerns an impending intervention by a driver assistance system, in particular the activation of a braking system, the advance warning can be given to an attentive driver between 1 s and 100 ms before the intervention. A less attentive driver (i.e., a driver who is recognized as inattentive) can be warned earlier, for example, between 2 s and 400 ms before the intervention.

[0026] In contrast to, for example, an acoustic warning, the kinesthetic jolt can be very subtle, so that the driver may perceive it as informative but not annoying. A passenger other than the driver may also experience the kinesthetic jolt as less annoying than, for example, an acoustic warning.

[0027] In one embodiment of the method, it is determined that a predetermined reaction by the driver to the advance warning has been lacking for a predetermined period of time or that a predetermined time interval to an event about which a warning is given has elapsed. In this case, further warning signals can be issued to the driver. The further warning signals can correspond to the main warning and use the same or different sensory channels of the driver. In particular, an optical, an acoustic, a haptic and a kinesthetic channel are available for the main warning. Thus, in a method according to the invention, it can be provided that the main warning is only issued if the predetermined reaction by the driver has been lacking for the predetermined period of time and / or if a predetermined time interval to the event about which a warning is given has elapsed.

[0028] A further aspect of the present invention relates to a processing device for controlling a driver assistance system of a motor vehicle.

[0029] The processing device can be configured to execute a method described herein in whole or in part. For this purpose, the processing device can comprise a programmable microcomputer or microcontroller, and the method can be at least partially in the form of a computer program product with program code means. The computer program product can also be stored on a computer-readable data carrier. Features or advantages of the method can be transferred to the control device, or vice versa.

[0030] The processing device can in particular be configured to carry out the following steps: detecting information indicating an impending intervention of a driver assistance system in the control of the motor vehicle; detecting information about a state of attention of a driver of the motor vehicle; generating control signals for providing a pre-warning before the intervention, wherein the control signals are generated in such a way that the pre-warning comprises a visual, acoustic or haptic first warning signal and that the pre-warning comprises, in addition to the first warning signal, a second warning signal in the form of a kinesthetic jerk if the driver is inattentive according to the detected information about his state of attention.

[0031] According to a further development, the processing device can further be configured to determine whether a predetermined reaction of the driver to the advance warning occurs within a predetermined time; and to generate control signals for providing a main warning prior to the intervention, which follows the advance warning, if the predetermined reaction of the driver fails to occur within the predetermined time. The main warning comprises an acoustic and / or a visual warning signal. The main perception preferably addresses at least two perception channels, e.g., a visual and an acoustic one.

[0032] A further aspect of the invention is a motor vehicle with a driver assistance system, wherein the motor vehicle comprises the following elements: a processing device according to the above-mentioned aspect of the invention; an optical, acoustic or haptic first output device for providing the first warning signal as a function of the control signals; an electric drive motor; and a control device for the electric drive motor, wherein the control device is configured to change a longitudinal acceleration of the motor vehicle by means of the electric drive motor as a function of the control signals in order to generate the kinesthetic second warning signal.The motor vehicle therefore comprises an electric drive motor which, through appropriate control by means of the control device, is designed to change the longitudinal acceleration of the motor vehicle and in this way to cause the kinesthetic jerk which forms the second warning signal of the advance warning.

[0033] The change in longitudinal acceleration can occur in a positive or negative direction, thus increasing or decreasing the longitudinal acceleration. Negative longitudinal acceleration can also be controlled by a braking system of the motor vehicle. In addition to the electric drive motor, another drive motor can be provided on board the motor vehicle, in particular an internal combustion engine. By controlling the electric motor, the kinesthetic jerk can be controlled very sensitively and with minimal resources. If the electric motor can be used for recuperation, the provision of the kinesthetic jerk can be almost energetically neutral if the negative longitudinal acceleration is used to charge an intermediate storage device and the positive longitudinal acceleration is caused using energy from the intermediate storage device.

[0034] The invention will now be described in more detail with reference to the accompanying drawings, in which:

[0035] Figure 1 a system; and

[0036] Figure 2 illustrates a flow chart of a process.

[0037] Figure 1 shows a system 100 with a motor vehicle 105 that can be controlled by a driver 110 on board and on which a driver assistance system 115 is located.

[0038] The driver assistance system 115 is designed to send warning signals to the driver

[0039] 110. For this purpose, the motor vehicle 105 comprises a processing device 120, which is connected to an interface 125, a first output device 130, and a control device 135 for an electric drive motor 145 of the motor vehicle 105. Furthermore, a detection device 140 is provided to detect the driver 110.

[0040] Information indicating an impending intervention of a driver assistance system in the control of motor vehicle 105 can be received via interface 125. The information can originate from another system or subsystem on board motor vehicle 105 and, in particular, indicate an impending event. The event can, for example, include an impending activation of a braking system, e.g., to avoid a collision of motor vehicle 105 with another object. Preferably, the event is assigned a time in the future at which the event is expected to occur.

[0041] The first output device 130 is configured to utilize an optical, acoustic, or haptic sensory channel of the driver 110. For this purpose, the first output device 130 may comprise a visual display, a loudspeaker, or a haptic actuator. The haptic actuator may, for example, vibrate a steering wheel, a seat, or an armrest of the driver.

[0042] The control device 135 is configured to control the electric drive motor 145 such that a kinesthetic jerk is transmitted to the driver 110 across the entire motor vehicle 105. The kinesthetic jerk preferably extends in the longitudinal direction of the vehicle 105 and can be effected, for example, by controlling a torque provided by the electric drive motor 145. By means of the second control device 135 and the electric drive motor 145, the motor vehicle 105 can be briefly accelerated or decelerated in the longitudinal direction such that the driver 110 perceives the change in acceleration.

[0043] The perception of the kinesthetic jerk can act on receptors of the musculoskeletal system of the driver 110. Such receptors can include, in particular, muscle spindles or Golgi tendon organs. The change in longitudinal acceleration is preferably dosed such that the perception of the kinesthetic jerk by the driver 110 occurs at least partially consciously. In particular, the driving speed of the motor vehicle 105 may not change significantly or may not be perceptible to the driver 110 due to the provided jerk.

[0044] The detection device 140 can be used to determine the level of attention of the driver 110. The detection device 140 can, for example, comprise an interior camera that detects facial expressions, blinking, or pupil dilation of the driver 110. Other possible detection devices 140, such as a steering angle sensor or a pedal sensor, can also be used.

[0045] The processing device 120 can vary the provision of a warning signal in terms of type, strength, and time interval before an event to which the warning relates. In particular, the more inattentive the driver 110 is, the earlier the advance warning can be provided. Two independent sensory channels can be used for the advance warning, one of which can be triggered by the first output device 130 and the other by the kinesthetic jolt. Under certain circumstances, a main or acute warning can be issued at a later time, for which two independent sensory channels of the driver 110 can also be used. The output devices 130, 135 and / or another output device on board the motor vehicle 105 can be used for this purpose. One or more channels used for the acute warning can be different from the channels used for the advance warning.

[0046] Figure 2 shows a flowchart of a method 200 for providing a warning to a driver 110.

[0047] In a step 205, information indicating an impending intervention of the driver assistance system 115 in the control of the motor vehicle 105 can be acquired. The information can relate to an event and an associated point in time in the future. The event can be predicted for the point in time, and it can generally be provided that the driver 110 is then encouraged by one or more warnings to prevent the event from occurring. In a step 210, which can occur before, after, or simultaneously with step 205, a level of attention of the driver 110 can be determined. For this purpose, the driver 110 can be acquired using the acquisition device 140.

[0048] Subsequently, two warning signals can be issued simultaneously to provide the driver 110 with advance warning of the intervention. In a step 215, a first warning signal can be issued by the first output device 130, while in a step 220, a second warning signal can be provided by the control device 135 and the electric drive motor 145. The first warning signal is provided visually, acoustically, or haptically, and the second warning signal comprises a kinesthetic jolt that encompasses the entire motor vehicle 105.

[0049] In a step 225, it can be checked whether a predetermined reaction of the driver 110 can be detected. This reaction can be suitable for preventing the event about which a warning is intended to occur. For example, if a warning is given about leaving a lane, the reaction of the driver 110 can include changing the course of the motor vehicle 105 so that the lane is maintained. Various reactions to the warning are often possible. In the above example, the driver 110 could, for example, actively control a lane change.

[0050] If the predetermined response is detected, method 200 can end. Otherwise, in step 230, a check can be made to determine whether a predetermined time has elapsed during which the response could not be detected despite the warning signals provided. If this is not the case, the process can return to step 225.

[0051] Once the time has elapsed, further warning signals can be issued to the driver 110. Analogous to steps 215 and 220, a further first warning signal and a further second warning signal can be issued in steps 235 and 240. The further warning signals can be issued using any output device, for example, again using the first output device 130. The warning signals provided in steps 235, 240 can correspond to a main warning and can be clearer, louder, brighter, more penetrating, or more aggressive than the warning signals in steps 215, 220, which can correspond to a pre-warning.

[0052] Accordingly, it can be accepted at this point that a warning signal could be perceived as disturbing by the driver 110 or another person on board the motor vehicle 105. If one of the additional warning signals includes a kinesthetic jolt, this jolt can be so long or so strong that it can be perceived by any person on board the motor vehicle 105. The driving speed of the motor vehicle 105 can be noticeably changed by the kinesthetic jolt of the main warning.

[0053] If the occurrence of the event for which a warning was intended is likely even after the main warning in steps 235, 240, the actual intervention, such as active control of the motor vehicle 105, can take place in a step 245. In particular, the motor vehicle 105 can be controlled longitudinally and / or transversely. More preferably, the motor vehicle 105 can be controlled into a safe driving state, which can include, for example, stopping or coasting. A driving intervention by the driver 110 can be overridden in this case.

Claims

Claims 1. Method (200) for operating a driver assistance system (115) of a motor vehicle (105), comprising the following steps: Acquiring (205) information indicating an impending intervention by the driver assistance system (115) in the control of the motor vehicle (105); Providing (215, 220) an advance warning directed to a driver (110) of the motor vehicle (105) before the intervention, wherein the advance warning comprises a first and a second warning signal, wherein the first warning signal is given optically and / or acoustically and / or haptically (215) and the second warning signal (220) comprises a kinesthetic jerk; Providing (235, 240) a main warning prior to the intervention, following the pre-warning in time, wherein the main warning includes an acoustic and / or a visual warning signal.

2. Method (200) according to claim 1, wherein the kinesthetic jerk comprises a temporary change in the longitudinal acceleration of the motor vehicle (105).

3. Method (200) according to claim 2, wherein the longitudinal acceleration is changed relative to a driver-controlled setting.

4. Method (200) according to one of claims 2 or 3, wherein the longitudinal acceleration is changed with a predetermined profile.

5. Method (200) according to one of the preceding claims, wherein the kinesthetic jerk is performed such that it has a duration in the range of 300 ms to 1500 ms, in particular in the range of 300 ms to 450 ms.

6. Method (200) according to one of the preceding claims, wherein the kinematic jerk is designed to cause a deceleration of the vehicle, wherein the deceleration does not exceed 1 m / s². 2 , in particular not more than 0.8 m / s 2 amounts.

7. Method (200) according to claim 6, wherein the kinesthetic jerk is performed such that a maximum deceleration in the range of 0.7 m / s is achieved. 2 up to 0.8 m / s 2 lies.

8. Method (200) according to one of the preceding claims, wherein the kinesthetic jerk is performed such that the change in acceleration achieved over time is greater than or equal to 10 m / s². 3 is.

9. Method (200) according to one of the preceding claims, wherein a level of attention of the driver is determined (210); and wherein the pre-warning with the second warning signal is only provided if it is determined that the driver is inattentive.

10. Method (200) according to one of the preceding claims, wherein it is determined (225) whether a predetermined response of the driver to the pre-warning (215, 220) occurs within a predetermined time; and the main warning (235, 240) is only provided if the predetermined response of the driver fails to occur within the predetermined time.

11. Processing device (120) for controlling a driver assistance system (115) of a motor vehicle (105), wherein the processing device (120) is configured to perform the following steps: Acquiring (205) information indicating an impending intervention by the driver assistance system (115) in the control of the motor vehicle (105); Capturing (210) information about the attentional state of a driver of the motor vehicle (105); Generating control signals to provide (215, 220) an advance warning before the intervention, wherein the control signals are generated in such a manner, that the pre-warning comprises a visual, acoustic, or haptic first warning signal; and that, in addition to the first warning signal, the pre-warning comprises a second warning signal (220) in the form of a kinesthetic jolt if the driver is inattentive according to the acquired information about their state of attention. Processing device (120) according to claim 11, wherein the processing device (120) is further configured to Determine (225) whether a predetermined response by the driver to the pre-warning (215, 220) occurs within a predetermined time; and generate control signals to provide (235, 240) a main warning prior to intervention, following the pre-warning, if the predetermined response by the driver fails to occur within the predetermined time, the main warning comprising an audible and / or a visual warning signal.Motor vehicle (105) with a driver assistance system (115), wherein the motor vehicle (105) comprises the following elements: a processing unit (120) for controlling the driver assistance system (115) according to claim 11 or 12; an optical, acoustic or haptic first output unit (130) for providing the first warning signal depending on the control signals; an electric drive motor (145); and a control device (135) for the electric drive motor (145), wherein the control device (135) is configured to change a longitudinal acceleration of the motor vehicle (105) by means of the electric drive motor (145) depending on the control signals in order to generate the kinematic second warning signal.

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