METHOD AND CONTROL DEVICE FOR WARNING A DRIVER OF A MOTOR VEHICLE AND A MOTOR VEHICLE WITH SUCH A CONTROL DEVICE

Description

[0001] The invention relates to a method and a control device for warning a driver of a motor vehicle and to a motor vehicle with such a control device.

[0002] Interior cameras are increasingly common in motor vehicles, capable of monitoring the driver's head position and visual attention. Based on this data, interventions in driving behavior and driver assistance are possible as soon as a reduction in attention is detected. Such technologies for enhancing driving safety are playing an increasingly important role in the evaluation of vehicle safety systems and are, for example, a relevant component of strategy programs published by vehicle safety organizations, such as those published by the European New Car Assessment Programme (Euro NCAP).However, in order to enable such adapted interventions to support the driver, a driver perception must first be modeled and compared with the vehicle's environment.

[0003] German patent application DE 10 2012 214 852 A1 describes a method for supplementing object information assigned to an object located in the vicinity of a vehicle. The method involves reading sensor information representing a driver's reaction to an object within the driver's line of sight. This sensor information is then evaluated to obtain recognition information indicating whether the driver has recognized the object. This method thus makes it possible to determine whether an object that is difficult to see, for example, due to adverse weather conditions or because the driver is distracted or fatigued, has actually been recognized by the driver.If the driver of a motor vehicle fails to detect a potentially dangerous object, such as one that poses a risk of collision, autonomous braking can be initiated. This method for monitoring the driver's visual attention is based on sensor data from the vehicle and an assessment of the driver's vision using head and / or eye positions within the vehicle. Potentially dangerous objects located in the vicinity of the vehicle but not visible to the driver are not considered in this process.

[0004] EP 1 865 479 A1 discloses a calculation device for an area of ​​a vehicle environment information device in which a hidden obstacle approaching the vehicle is likely to exist, based on driving information acquired by the vehicle. If the hidden obstacle is detected, an information device provides information about the hidden obstacle.

[0005] GB 2536474 A discloses a method for monitoring a driver's situational awareness. It includes receiving eye-tracking information, tracking information of one or more objects outside the vehicle, and correlating these to determine whether the driver's eye movement corresponds to a relative movement of the external objects.

[0006] It is an object of the invention to provide a solution with which it can be decided when the attention of a driver of a motor vehicle should be directed to an object that is potentially dangerous to him.

[0007] This problem is solved by a method and a control device for warning a driver of a motor vehicle according to the independent claims. Advantageous embodiments with expedient and non-trivial further developments of the invention are specified in the dependent claims.

[0008] The inventive method for warning a driver of a motor vehicle comprises the steps according to claim 1.

[0009] In an unclaimed embodiment, the device checks whether it identifies the first object within the field of view between the vehicle and the first object, as determined by the received position data and its own position. If the first object is not identified by the device and the first object creates a potentially critical situation for the vehicle, the predefined warning sequence is initiated.

[0010] The method according to the invention thus serves to warn a driver of a motor vehicle about an object that is hidden from view. For this purpose, position data of a potentially hidden object, hereinafter referred to as the first object, is first transmitted to the motor vehicle. This position data is received by a communication device of the motor vehicle designed for this purpose, for example by means of vehicle-to-X, car-to-X or, in particular, car-to-car communication. The communication device external to the vehicle can therefore be, for example, another road user, such as another vehicle, or an infrastructure unit or the hidden object itself, in particular another vehicle. Furthermore, the motor vehicle has access to data acquired by the motor vehicle itself with a corresponding detection device.The detection system includes, for example, vehicle sensors such as a front camera, side cameras, a rear camera, optical distance and speed sensors such as lidar (light detection and ranging) devices, radar devices, or ultrasonic devices. The data provided by these systems contains information about the vehicle's surroundings, such as objects in the vicinity of the vehicle, like other road users, buildings, vegetation, traffic signs, obstacles such as hills or mountains, people, or objects. An object detected in the vehicle's surroundings by the detection system is referred to below as the second object. The vehicle also has information about its current location.This is achieved, for example, by locating the vehicle using GPS data or by comparing the objects detected in the vehicle's environment with information from maps stored in the vehicle.

[0011] Based on the aforementioned data provided by the vehicle—that is, based on the position data of the first object, the detected vehicle environment, and the vehicle's own position—a further step checks whether the first object is obscured from the vehicle's view, meaning whether the first object is, in principle, visible from the vehicle. For this purpose, the field of view—that is, the area of ​​the vehicle's surroundings visible to the detection device and / or the driver—is first defined based on the received position data and the vehicle's own position. The field of view is therefore at least a sub-area of ​​the detection device's overall detection range.If the first object is not detected within the defined field of view—that is, if an object detected by the detection device within the field of view cannot be clearly identified as the first object—it can be concluded that the first object is not visible from the vehicle and is therefore obscured from it. Additionally or alternatively, it can be concluded that the first object is not visible from the vehicle and is therefore obscured from it if the detection device detects a second object that is located between the vehicle and the first object from which the position data is provided. The second object does not need to be detected or identified; it is sufficient if it is detected that something—that is, an obstacle designated as the second object—is located between the vehicle and the first object.

[0012] When identifying the first object with the detection device, the prerequisite is that the position data of the first object lies within the detection range of the vehicle's detection device. If this condition is not met, the system only checks whether a second object obscuring the first is detected. Additionally, a minimum identification probability can be defined and stored in the vehicle. As soon as the first object is identified with a probability greater than this minimum identification probability as the first object whose position data was received by the vehicle, the first object is considered uniquely identified and therefore unobscured.This is particularly relevant in cases of partial obscuration of the first object, for example by a relatively sparse forest, which allows the system to detect second objects that obscure the first. However, these second objects may not completely obscure the first object, meaning the first object could still be visible to the driver. Furthermore, when identifying the first object, object-specific characteristics, such as its size, color, and surface texture, can be taken into account. These characteristics were received by the vehicle in addition to the first object's position data.

[0013] The first object could be, for example, another vehicle, but it is not visible to the vehicle itself because there is a hill or a forest between the road the vehicle is traveling on and the road on which the other vehicle (the first object) is traveling. The second object, which obscures the first object, could therefore be an obstacle, such as a cluster of trees, that block the view of the first object (the other vehicle). If the second object is, for example, a hill, then the vehicle traveling behind the hill, perhaps on a road that intersects the road the vehicle is currently traveling on, cannot be detected by the vehicle's radar or its front and side cameras.Based on the position data transmitted by the first vehicle (the first object) via car-to-car communication, the vehicle is aware of the presence and position of this other vehicle. However, because there is an obstacle within the vehicle's field of view—in this case, the hill—the first object cannot be detected by the vehicle's sensors. Therefore, the other vehicle is not identifiable, and a second object is detected that obscures the first vehicle.

[0014] However, the driver of the vehicle can still be informed of the presence of the other vehicle, i.e., the first object. This occurs, for example, whenever a potentially critical situation arises for the vehicle due to the detected, albeit obscured, first object. In a further step of the process, it is checked whether a collision between the first object, from which the position data was received, and the vehicle is possible. Various assumptions regarding the driving behavior and movement of both the first object and the vehicle itself are taken into account.

[0015] If it is determined that the first object is obscured and that this object could potentially create a critical situation for the vehicle, a specific warning procedure is initiated. This warning procedure, known as the warning cascade, distinguishes whether the vehicle is still within a safe distance from the location of the potentially critical situation, where there is no immediate danger to the vehicle and its occupants, or whether the vehicle is already in a potentially critical area or even an actual critical area.Depending on the likelihood of an actual collision with the first object and how close in time the potential collision is to occurring—that is, how close in time the potentially critical situation is likely to arise—various warning signals are issued to the driver. These warning signals can range from a relatively simple display on a screen inside the vehicle, such as an illuminated light or text message, to audible warnings or even intervention in the vehicle's behavior, for example, by automatically braking. The warning signals thus escalate depending on the urgency with which the driver should react to them. Initially, for example, a relatively intrusive warning signal, such as an illuminated light, might be activated.If the driver fails to react, this warning signal is intensified, for example by additionally activating the acoustic warning tones. If even this intensified warning signal does not lead to the desired reaction from the driver, the vehicle may, for example, brake automatically.

[0016] Generally, various sequences of the individual process steps are possible. In a first variant of the process, position data from all objects in the vicinity of the vehicle are initially received. Based on this position data, and taking into account the detected vehicle environment and the vehicle's own position, it is determined whether the individual objects are obscured from the vehicle's view. For all obscured objects, it is then determined whether the respective obscured objects create a potentially critical situation. If a potentially critical situation exists for a particular object, the predefined warning cascade is initiated for that object. In a second variant, all objects in the vehicle's vicinity identified based on received position data are first examined with regard to the potentially critical situation that these objects could create for the vehicle.For all potentially critical objects—that is, all objects that could create a potentially critical situation for the vehicle—the system checks whether these objects are obscured by other objects. Subsequently, a corresponding warning cascade is initiated for all objects that create a potentially critical situation and are subsequently identified as obscured. Therefore, according to the invention, it is not predetermined whether a first object, whose position data has been received by the vehicle, is initially checked for a potentially critical situation caused by that object or for obscuration by a second object. The invention is thus applicable to all critical driving situations in which the obscuration of an object in the vehicle's surroundings plays a role.

[0017] Using the method according to the invention, it is therefore possible to check a first object in the vicinity of the motor vehicle, regardless of whether it is located in an area detectable by the vehicle's detection device or not, to determine whether it poses a potential danger to the vehicle and its occupants, and whether it is visible to the driver or whether it is obscured by a second object. Based on the object's position and the vehicle's own position, the visibility of the object to the driver is calculated, and the driver is informed and warned of the object's presence in a timely manner.This method uses a warning signal to draw the driver's attention to potentially critical objects that are temporarily out of the driver's field of vision. For example, a warning signal can be triggered by appropriate light signals, directing the driver's attention in the direction of the first detected object as soon as it is no longer obscured and thus visible. This also enables a particularly high sensitivity of vehicle functions to support and assist the driver by taking into account objects that are not visible to the vehicle's sensors or the driver. This method thus allows for the development of driver assistance systems that react particularly quickly.

[0018] The invention provides that the first object is located behind the vehicle and that it is checked whether the first object is obscured by the second object when the driver looks in a vehicle mirror. If the first object is located in the rear area of ​​the vehicle and can therefore only be detected by the driver looking in the rearview mirror and not by looking through the windshield or with the front sensors themselves, the method is also designed to identify obscured objects behind the vehicle and, if necessary, to warn of any potentially critical situations that may arise. The method is thus designed for obscured objects located behind the vehicle.This enables a coverage area of ​​the entire vehicle environment, in which hidden objects that could create a potentially critical situation for the vehicle are scanned and warnings are issued if necessary.

[0019] The invention provides that the visibility of the first object on the vehicle mirror is determined based on the received position data, predetermined imaging properties of the vehicle mirror, the position setting of the vehicle mirror, and the eye and / or head position of the vehicle driver as detected by the detection device. Thus, if the first object is located in a rear compartment of the vehicle and is only visible to the driver using the vehicle mirror, a potential imaging area of ​​the first object on the vehicle mirror is determined. This imaging area itself is determined based on the properties of the vehicle mirror stored in the vehicle's memory, its setting and thus its orientation relative to the driver and the vehicle itself, and taking into account the driver's line of sight.If a second object obscuring the first object is detected between this imaging area in the vehicle mirror and the first object, and if the potentially critical situation for the motor vehicle arises due to the obscured first object, the warning cascade specified in the invention is initiated.

[0020] According to the invention, if the first object is a vehicle, current motion data is received from the first object. Based on this data, a potential motion trajectory of the first object is determined. If it is determined that this potential motion trajectory intersects with a potential self-motion trajectory of the vehicle, this is recognized as the resulting potentially critical situation. Using the current motion data of the first object, the vehicle has information about its current direction of travel, speed, and, for example, its current route. This first object could be another vehicle transmitting its position data to the vehicle via Vehicle-to-X communication. Thus, not only is the position of the first object known, but its potential motion trajectory can also be estimated.If a collision risk is detected between the first object and the vehicle, it can be determined whether the first object poses a potentially critical situation for the vehicle, such as a collision. The vehicle's potential trajectory can be determined, for example, using a route from the navigation system or, alternatively, derived from the current driving behavior. This takes into account the current speed and direction of travel. Furthermore, the trajectory can be supported by monitoring the driver's position using interior sensors: for example, a shoulder check can indicate a possible overtaking maneuver or a potential lane change by the vehicle.Furthermore, typical driving routes stored in the memory unit can be taken into account, as well as the activation of a turn signal, changes in speed such as braking before a turn, or gesture recognition methods that can reveal the driver's intentions. These gestures might include, for example, the aforementioned shoulder check, a glance in the rearview mirror, or a head turn. By considering the potential trajectory of the first object as well as the vehicle's own trajectory—where multiple potential trajectories can be assumed for each—a particularly reliable warning can be issued before a potentially critical situation arises.Multiple potential trajectories arise, for example, from speed variations of the driver of the other vehicle and / or the vehicle, junctions between the current positions and the location of the potential collision, or influences from other road users, such as other vehicles traveling in front of the other vehicle or the vehicle. In particular, when multiple potential movement trajectories and potential self-movement trajectories are determined and considered, this ensures particularly reliable support for the driver of the vehicle in the event of a concealed first object that creates the potentially critical situation.

[0021] According to the invention, it is alternatively or additionally provided that, in order to verify whether the first object creates a potentially critical situation for the motor vehicle, an object criticality value, quantifying the hazard potential emanating from the first object, and a situation criticality value, quantifying the hazard potential emanating from a potential traffic situation, are determined. The potentially critical situation is then assessed based on these values. Which stage of the warning cascade, i.e., which type of warning is issued in a potentially critical situation, thus depends on two criticality values. The so-called object criticality value takes into account the direction and, for example, the speed at which the first object is moving.This process takes into account factors such as whether the other vehicle, which is the first object to transmit its position data to the motor vehicle, is moving away from the motor vehicle itself or whether it is approaching it very slowly. In both of these situations, the object criticality value would be very low. A parked vehicle transmitting its position data to the motor vehicle, for example, would have an object criticality value of almost zero, since a collision with the parked vehicle can generally be ruled out unless the parked vehicle suddenly starts moving and approaches the motor vehicle. Conversely, a vehicle approaching an intersection at a relatively high speed, towards which the motor vehicle itself is also moving, would have a particularly high object criticality value, which will be factored into the overall situation assessment.

[0022] Situational criticality takes into account, for example, the applicable traffic regulations and thus determines criticality values ​​depending on which lane the vehicle is traveling in, whether the obscured first object is a traffic light or another traffic safety-relevant device, and thus estimates the criticality of the potential danger to the vehicle arising from the presence of the obscured first object in relation to the situation. A traffic light at an intersection, for example, would reduce the situational criticality at the intersection, since the traffic light sends clear signals to both the approaching vehicle and, for example, to another approaching vehicle.In contrast, the situational criticality of a potential collision between a motor vehicle and another vehicle at an intersection without traffic lights, where, for example, the "right before left" rule or the rules of a priority road apply, would be rated with a higher situational criticality, since such an intersection generally presents a higher risk potential for the occupants of both the vehicle in question and the other vehicle. If multiple objects are present in the vicinity of the vehicle, the overall risk potential of the situation is assessed and expressed as a situational criticality value.

[0023] Ultimately, by considering the potential hazards, which can be quantified using the object criticality value and the situation criticality value, a particularly appropriate warning cascade can be determined based on the actual expected hazard potential of the potentially critical situation, and the warning cascade can be adjusted and selected accordingly. This prevents, for example, an unnecessarily intrusive warning being issued to the driver of the vehicle, even though the potentially critical situation, despite the first object being obscured, poses only a relatively low hazard potential for the vehicle's occupants.

[0024] In a further advantageous embodiment of the invention, the vehicle receives position data from the external communication device only if the device and / or the first object are located within a predetermined radius of the vehicle. Thus, the vehicle does not receive position data from a first object that is, for example, several kilometers away. By selecting the predetermined radius within which position data is received, the vehicle is prevented from receiving data from objects that are irrelevant to it, such as those located too far away. This represents a particularly useful limitation of the amount of data received by the vehicle, as only the data actually relevant to the vehicle is received.The specified radius can only refer to the communication device from which the position data is sent. This could be, for example, an infrastructure feature such as a traffic light system. Information, such as upcoming red phases of the traffic light, is only relevant for determining potentially critical situations for the vehicle if the traffic light system is located within the specified radius of the vehicle. Furthermore, it is possible that the communication device sending the position data is located outside the specified radius of the vehicle, but the first object detected by the communication device is located within the specified radius.This covers, for example, the situation where an infrastructure feature, such as a traffic light, detects a cyclist and transmits the cyclist's position data to the motor vehicle. If the traffic light is located outside the detection radius, but the cyclist is traveling towards the motor vehicle and is already within the vehicle's detection radius, the relevant position data will still be transmitted from the infrastructure feature to the motor vehicle. Ultimately, this ensures that all data relevant to the motor vehicle is actually transmitted to it.

[0025] In a further advantageous embodiment of the invention, another vehicle or infrastructure unit comprises the vehicle-external communication device and is the first object. Thus, the first object is another vehicle, such as another motor vehicle, or an infrastructure unit, such as a traffic light system or a building containing an external camera. This object, i.e., the other motor vehicle or the traffic light system, transmits its own position data to a corresponding communication device of the motor vehicle using Vehicle-to-X, Car-to-X, or Car-to-Car communication.This enables other vehicles or infrastructure units to transmit their position data to the motor vehicle independently and without a request or activation by another object, so that, based on this data, the driver of the motor vehicle can ultimately be warned if this other vehicle or infrastructure unit is obscured from the motor vehicle and a potentially critical situation exists due to this so-called first object.

[0026] In another embodiment, the system includes a separate vehicle or infrastructure unit that houses the vehicle's external communication device. This unit uses a sensor to detect the first object, and the vehicle then receives the position data of this first object. It is also possible that the first object is not the device that transmits the first object's position data to the vehicle. For example, the first object could be another vehicle or infrastructure unit that is detected by a sensor, such as a front camera on the other vehicle or an external camera on the infrastructure unit. The position data of this detected object is then transmitted to the vehicle via, for example, Vehicle-to-X, Car-to-X, or Car-to-Car communication.This makes it possible to capture not only vehicles or infrastructure units that have their own communication devices for sending position data as the first objects, but also other objects, such as bicycles or vehicles without Vehicle-to-X communication capabilities, within the framework of the process.

[0027] Another embodiment of the invention provides that map data, particularly 3D map data, is used to check whether a second object, which obscures the first object, is located within the field of view between the vehicle and the first object. Map data, such as maps showing forested areas, can be stored in the vehicle. Alternatively or additionally to the vehicle environment data captured by the detection device, this map data can be used to determine whether a second object, obscuring the first object, is located between the vehicle and the first object. Map data containing topographic information, which allows, for example, the estimation of a hill's height, is particularly advantageous in this context.This makes it particularly easy to determine whether the line of sight between the vehicle and the first object is actually obscured by the second object, in this situation the hill, or whether the first object is still visible from the vehicle, for example in the case of a relatively low hill or a relatively tall vehicle, and is merely outside the detection range of the sensor. When determining whether the first object is obscured by the second object, the dimensions of both the objects and the vehicle are taken into account, i.e., their height, length, and / or width.

[0028] The occlusion of the first object can therefore be detected in various ways. Firstly, it can be detected that the first object is not visible within the vehicle's field of view; that is, the first object is not recognized as the first object by the detection device and / or a second object is detected that obscures the first object. Secondly, the occlusion of the first object may already be known when the position data is transmitted to the vehicle, for example, via Vehicle-to-X communication. This is the case, for instance, if the first object is detected by the sensor unit of another vehicle. Both of these methods of occlusion detection identify dynamic occlusions of the first object, which are often dependent on the movement of the first object.Furthermore, static occlusions of the first object can be detected, as is possible, for example, using map data that contains information about a landscape and vegetation profile, i.e., information about the positions of hills, houses and vegetation.

[0029] In a further advantageous embodiment of the invention, it is provided that, in addition to the received position data and the vehicle's own position, the driver's gaze direction is taken into account when determining the field of view by means of the detection device. It is then checked whether, starting from a viewing origin along the viewing direction between the driver and the first object, a component of the vehicle obscuring the first object is detected. The vehicle's field of view between the vehicle and the first object can thus be specified more precisely. For this purpose, the driver's gaze direction is taken into account, which can be determined, for example, using an interior camera that captures the driver's eye and head positions. The viewing origin is therefore defined as the position of the driver's eyes.This results in a more limited field of view than just the area between the vehicle and the first object, allowing for a particularly precise determination of the actual visibility of the first object and thus the actual obscuration by the second object. Furthermore, this method makes it possible to ascertain whether the first object is obscured by a component of the vehicle itself, either in addition to or instead of a second object located outside the vehicle. This component of the vehicle obscuring the first object could be, for example, the A-pillar, located between the left side window and the windshield, or a rearview mirror positioned in the upper area of ​​the windshield.The prescribed warning cascade can therefore also be initiated if the first object is obscured by a component of the motor vehicle and this first object creates a potentially critical situation for the motor vehicle.

[0030] To determine the driver's gaze direction, a perception area can be estimated even without access to data from the interior camera. This can be done, for example, by estimating a head height range based on the driver's seat position. Since the driver's current head position and rotation, as well as their precise gaze direction, are unknown in this case, a potential perception area of ​​up to 360 degrees is assumed, which also includes the driver's shoulder check. If access to data from the vehicle interior, such as from an interior camera, is available, this perception area can be narrowed and specified by determining the area of ​​the driver's current visual attention. For this purpose, the driver's attention area can be estimated based on the head position and rotation detected by the interior camera.The existing detection system can accurately measure the driver's attention area by recognizing the current direction of gaze. Therefore, the driver's perception area can be determined with varying degrees of accuracy depending on the vehicle's detection system.

[0031] In an unclaimed embodiment, it is provided that if it is detected that the first object is causing a potentially critical situation for the vehicle, but the first object is not obscured, the predetermined warning cascade is only initiated if it is determined that the driver's gaze is not directed at the unobstructed first object. Thus, for example, if it is determined using interior cameras that the driver's eye and head positions indicate that the driver has not seen the first object, even though it is actually visible to him because it is not obscured, but it is determined that this first object is causing a potentially critical situation for the vehicle, the predetermined warning cascade provided for in the inventive method is nevertheless initiated.

[0032] In addition to or as an alternative to the driver's direct line of sight, their visual attention can also be determined—that is, the probability of the driver actually perceiving the first object. This involves considering characteristics of the driver and the vehicle's surroundings, particularly the first object, such as its color and surface texture, and verifying whether the driver is aware of the object and its relevance. This is especially relevant for first objects located to the side of the vehicle, as these may not be directly seen or perceived by the driver. While they are theoretically visible, a warning about the presence and movement of this first object is still useful to prevent a collision.

[0033] In addition, or alternatively, the probability of perception, that is, the driver's visual attention, can be taken into account when assessing the potentially critical situation. For example, another vehicle painted in a relatively conspicuous color, such as a red vehicle, is more likely to be perceived by the driver than a dark green vehicle. If the potentially critical situation arises due to the dark green vehicle, a stronger warning signal can be activated when initiating the warning cascade than would be the case with the red vehicle in the same situation, since the driver is more likely to perceive the red vehicle and more quickly than the dark green vehicle once it enters their field of vision.

[0034] Another, unclaimed embodiment provides that if it is determined that the driver does not see the first object due to their detected gaze direction, the driver's gaze direction, as recorded by the detection device, is evaluated for a predetermined elapsed period. If it is determined that the driver did not see the first object during this period, the prescribed warning sequence is initiated. Thus, the warning sequence is not only initiated when the driver does not see the unobstructed first object at a specific time due to their gaze direction, but it is first checked whether the driver also failed to see the corresponding first object within a predetermined period, for example, within the last ten seconds or within the last few minutes.Only if it is confirmed, as can be determined in this way, that the driver has indeed not yet seen the first object, is the prescribed warning sequence initiated. This prevents repeated warning sequences from being triggered solely based on the driver's current line of sight, which are therefore neither necessary nor useful.

[0035] Alternatively or additionally, instead of the driver's gaze direction, their visual attention—that is, the probability with which they perceived the first object—can be considered. Thus, if it is determined that the driver does not perceive the first object based on the recorded gaze direction and / or visual attention, the driver's visual attention, recorded by the detection device, is evaluated over a predetermined elapsed period. If it is determined that the driver did not perceive the first object during this period, the predefined warning sequence is initiated. In other words, the system estimates how aware the driver is of the object at present.Initiating the warning cascade is also useful, for example, if the driver saw the first object within the specified time frame, but that object has since accelerated relatively sharply, creating a potentially critical situation. Since the driver did not see this acceleration of the first object, meaning they have an information deficit in this regard, the warning cascade can still be initiated. Similarly, the warning cascade can be initiated if the second object is, for example, a bicycle previously seen by the driver that changes direction while obscured from view.The driver can also be warned using the warning cascade about objects already seen by the driver, whose presence he may have since forgotten, for example due to a stop at a traffic light during which the object is obscured.

[0036] Another embodiment of the invention provides that if the predetermined warning sequence is executed to its end, an automatic emergency stop of the vehicle is performed to prevent the potentially critical situation from occurring. Within the warning sequence, particularly in the critical area—that is, the area shortly before the location and time of the potentially critical situation—it is possible for the vehicle to be brought to a stop without any reaction from the driver. This means that the vehicle can be brought to a standstill using the vehicle's brakes, which can be controlled electronically, for example, using brake-by-wire technology. Alternatively or additionally to the automatic emergency stop, an autonomous intervention, such as an evasive maneuver, can be performed to prevent a collision with the first object.Even if the driver does not react to the initiated warning sequence, the potentially critical situation can be automatically prevented shortly before it occurs. Alternatively or additionally, the driver's reaction time can be estimated using the vehicle's interior camera and taken into account when selecting the warning signal. For example, if the driver is currently distracted because they are entering a new destination into the vehicle's navigation system, their reaction time will be delayed, and the vehicle's automatic emergency stop may occur earlier than if the driver were attentive.

[0037] Additionally or alternatively, when initiating the warning cascade, consideration can be given to how long it will take for the driver to change their gaze and / or perceive the previously obscured first object once it is potentially visible to them, or once their attention is drawn to the object by the warning cascade. For this purpose, a perception delay on the part of the driver is estimated, and the warning cascade is initiated particularly early, taking this delay into account, so that at a desired time, depending on the current trajectory of the vehicle and the first object, the driver can see and perceive the first object.

[0038] To determine the driver's perception delay, driver behavior is recorded using the vehicle's sensor system and / or devices not covered by the vehicle's sensor system, such as the driver's fitness tracker, and then assigned to a driver state. Based on the driver's driving behavior, such as braking and acceleration patterns, the driver's eyelid frequency recorded by interior sensors, or the driver's heart rate measured by the fitness tracker, the driver's current state can be determined. For example, the following driver states can be distinguished: tired, under-challenged, and over-challenged. Furthermore, the driver can be assigned to a driver type, such as: novice driver, experienced driver, sporty driver, or cautious driver.To determine the driver type, for example, person-specific data can be stored in the vehicle, or past journeys undertaken by the driver with the vehicle can be evaluated. Depending on the driver type determined and the driver's state of mind assigned to them—that is, their cognitive condition—a typical perceptual delay, determined, for example, based on fleet data, is selected.For example, if a warning cascade is initiated and a lighting device inside the vehicle is activated, intended to direct the driver's attention to the direction where the previously obscured, unseen, or unperceived first object will be visible, these lights can be activated as particularly effective warning signals, tailored to the driver. This is because the timing of the activation takes into account the driver's perception delay. Furthermore, the perception delay can be personalized based on an analysis of the driver's perception delays observed during previous journeys with the vehicle.

[0039] Even if the first object creates a potentially critical situation for the vehicle, but this first object is not obscured by a second object, and the driver's gaze direction has been recorded by the interior sensors in such a way that it can be assumed that the driver did not look in the rearview mirror, either at that moment or within a previous period, in such a way as to see the detected area, and thus it can be assumed that the driver did not see the first object behind the vehicle, the prescribed warning sequence can still be initiated. It is therefore possible to precisely determine whether a first object located behind the vehicle is or was visible in the mirror when the driver looks in it.Alternatively, or in addition, it can be taken into account whether the first object in a digital mirror, which displays images of the vehicle's rear surroundings captured by a rear-view camera on a display in the vehicle, was seen and perceived by the driver. This allows, for example, blind spot warnings to be issued to the driver in a particularly specific way, also taking into account any obstructions to the first object that were detected.

[0040] According to the invention, a control device for a motor vehicle for warning a driver of the motor vehicle according to claim 8 is also provided.

[0041] According to the invention, a motor vehicle with the described control device is also provided, with which the described method for warning a driver of a motor vehicle can be carried out.

[0042] The invention also includes further developments of the method according to the invention, which have features already described in connection with the further developments of the motor vehicle according to the invention. For this reason, the corresponding further developments of the method according to the invention are not described again here.

[0043] An embodiment of the invention is described below. The following is shown: Fig. 1 is a schematic representation of a motor vehicle in whose vicinity a first object is hidden by a second object, wherein this representation does not correspond to the situation of the claimed invention; and Fig. 2 is a schematic representation of a motor vehicle behind which a hidden first object is located, wherein this situation represents the claimed invention.

[0044] The embodiment described below is a preferred embodiment of the invention. In this embodiment, the described components each represent individual features of the invention that can be considered independently of one another. Each of these features further develops the invention independently and can therefore be considered part of the invention individually or in a combination other than that shown. Furthermore, the described embodiment can also be supplemented by other features of the invention already described.

[0045] In the figures, functionally identical elements are each provided with the same reference symbols.

[0046] In Fig. 1 A motor vehicle 1 is depicted, moving along a road 2 towards an intersection 3. To the right of the motor vehicle 1 is a forest consisting of numerous trees 4. Another vehicle 10 is also approaching the intersection 3. Both the motor vehicle 1 and the other vehicle 10 are equipped with a control device 6, a communication device 7, and a detection device 5, which may be, for example, a front camera or a lidar device located in the front of the motor vehicle 1. The motor vehicle 1 receives position data from the other vehicle 10 via a communication link 8 between the communication device 7 of the other vehicle 10 and the communication device 7 of the motor vehicle 1. The other vehicle 10 thus represents the first object 10 whose position data is received by the motor vehicle 1.Using the communication link 8, data from the other vehicle 10 is provided to the motor vehicle 1, for example, using Vehicle-to-X, Car-to-X or Car-to-Car communication.

[0047] The other vehicle 10 is located within a predefined radius 11 of the motor vehicle 1 and typically also within a detection range 12 of the detection device 5 of the motor vehicle 1. After receiving the position data of the other vehicle 10, the control device 6 determines a line of sight 13 of the motor vehicle 1 to the other vehicle 10, based on the position data received from the other vehicle 10 and the motor vehicle 1's own position detected by the motor vehicle 1 itself. The detection device 5 also detects the surroundings of the motor vehicle 1. If the detection device 5 does not identify the other vehicle 10 within the determined line of sight 13 and / or detects a second object 4 located between the motor vehicle 1 and the other vehicle 10, the other vehicle 10 is identified as obscured.This second object 4 refers to the trees 4, which obstruct the direct view of the motor vehicle 1 to the other vehicle 10.

[0048] The system also checks whether the other vehicle 10 poses a potentially critical situation for vehicle 1, for example, the risk of a collision when both vehicles arrive at intersection 3 at the same potential time. If it is detected that the other vehicle 10 is obscured and a potentially critical situation for vehicle 1 arises due to the other vehicle 10, a predefined warning cascade is initiated. This cascade includes, for example, warnings of varying intensity depending on the proximity of the other vehicle 10 to the location of the potential collision. These warnings can include, for example, a corresponding display on a screen inside vehicle 1, audible or voice announcements, and an emergency stop of vehicle 1.

[0049] As an alternative to the other vehicle 10, the first object 10 can also be an infrastructure unit such as a traffic light system. The other vehicle 10 or the infrastructure unit can transmit its own position data as the so-called first object 10 to the communication device 7 of the motor vehicle 1 using Vehicle-to-X, Car-to-X, or Car-to-Car communication. Alternatively, the other vehicle 10 can also transmit position data of a first object 10 detected by the other vehicle 10, which could be, for example, a bicycle or another motor vehicle 1 that does not have the corresponding communication device. The other vehicle 10 or the infrastructure unit transmitting the position data of the first object 10 to the motor vehicle 1 is located within the specified radius 11 of the motor vehicle 1.

[0050] In addition to or as an alternative to the environmental data provided to vehicle 1, which includes the detected vehicle surroundings, the vehicle 1's own position, and the received position data of the other vehicle 10, map data, in particular 3D map data, can also be used in vehicle 1 to carry out the procedure for warning the driver of vehicle 1. For example, the map data can be used to check whether the trees 4 that obscure the other vehicle 10 are located within the field of view 13 between vehicle 1 and the other vehicle 10. The corresponding information about the forest located there can therefore also be derived from the map data stored in vehicle 1.This is particularly helpful if the second object 4 is a topological elevation, such as a hill, which may be stored in the vehicle 1 using 3D map data.

[0051] In addition to the one in Fig. 1 With the front camera sketched as a detection device 5, it is possible that the driver's gaze direction is also detected by components of the detection device 5 inside the vehicle 1. For example, an interior camera can determine the eye position and / or head position of the driver of the vehicle 1 and thereby restrict the field of view 13 so that only the field of view 13 actually visible to the driver of the vehicle 1 in the direction of the other vehicle 10 is considered. This makes it possible, for example, to detect obstructing components of the vehicle 1, such as the A-pillar or a rearview mirror of the vehicle 1.Even if no trees 4 obscure the other vehicle 10 for the driver of the motor vehicle 1, it can thus be determined whether the other vehicle 10 is obscured by components of the motor vehicle 1 itself and is therefore not visible to the driver of the motor vehicle 1.

[0052] If, based on the driver's line of sight in vehicle 1, it is determined that the other vehicle 10 is indeed unobstructed, but both the driver's current line of sight and a line of sight determined in the past (e.g., within the last ten seconds) indicate that the driver did not see the other vehicle 10, the prescribed warning sequence can still be initiated if the other vehicle 10 poses a potentially critical situation for vehicle 1. The prescribed warning sequence can therefore be carried out and initiated even if the other vehicle 10 is not actually obscured by the trees 4.

[0053] In addition to the position data of the other vehicle 10, it also transmits its current movement data, i.e., for example, its current direction of travel, its current speed, and its current route, to vehicle 1. Based on this movement data, a potential movement trajectory 17 of the other vehicle 10 can be calculated. If this potential movement trajectory 17 intersects with a potential movement trajectory 18 of vehicle 1, which, for example, results from a route selected by the driver in vehicle 1's navigation system, this is recognized as a potentially critical situation, and the predefined warning cascade is initiated.

[0054] Furthermore, to quantify the potentially critical situation and the associated selection of a stage in the predefined warning cascade, the hazard potential posed by the other vehicle 10 and the current driving situation can be estimated. For this purpose, both an object criticality value and a situation criticality value are determined. The object criticality value quantifies the hazard potential resulting from the direction and speed at which the other vehicle 10 and the vehicle 1 are approaching each other. Thus, a corresponding object criticality is determined. The situation criticality value provides information on the level of hazard potential under the prevailing traffic regulations, taking into account the road surface and traffic signs such as road signs or traffic lights.The situational criticality thus indicates the criticality of the potentially resulting collision of motor vehicle 1 with the other vehicle 10, taking into account the current situation.

[0055] In Fig. 2 Motor vehicle 1 and the other vehicle 10 are also sketched. In Fig. 2 However, the other vehicle 10 is driving on the same road 2 as the motor vehicle 1. The other vehicle 10 is behind the motor vehicle 1 and can therefore only be seen by the driver of the motor vehicle 1 by looking in a vehicle mirror 16. The road 2, which is in Fig. 2 The route is sketched, but has a curved course, which is why the other vehicle 10 is hidden from the driver of the motor vehicle 1 by the trees 4.

[0056] The visibility of the other vehicle 10 in the vehicle mirror 16 of the motor vehicle 1 is determined based on the received position data of the other vehicle 10, predetermined imaging properties of the vehicle mirror 16, a position setting of the vehicle mirror 16, and an eye or head position of the driver of the motor vehicle 1 detected by the detection device 5. Thus, the driver's position in the motor vehicle 1 is taken into account.If the other vehicle 10 is located behind the vehicle 1 and is therefore only visible to the driver of the vehicle 1 using the vehicle's mirror 16, and no second object 4 (e.g., no trees 4) is detected between the area of ​​view of the other vehicle 10 on the mirror 16 and the position of the other vehicle 10, but the driver's line of sight indicates that they have not yet seen the other vehicle 10, and this other vehicle 10 poses a potentially critical situation for the vehicle 1, the predefined warning sequence is nevertheless initiated. A potentially critical situation caused by the other vehicle 10 driving behind the vehicle 1 can arise, for example, if the other vehicle 10 approaches the vehicle 1 from behind at a particularly high speed, creating a risk of a potential rear-end collision.

[0057] In summary, it can be stated that, based on various raw data provided in the vehicle 1, it is determined whether the first object 10, i.e., the other vehicle 10, is obscured from the view of the driver of vehicle 1. This raw data includes the position data of the other vehicle 10, the first object 10, provided via the Vehicle-to-X, Car-to-X, or Car-to-Car communication link 8; the vehicle environment detected by the detection device 5; map data and location data of vehicle 1 for determining its own position; and information about the driver's direction of view, for example, based on sensor data from interior cameras of vehicle 1 that are part of the detection device 5. The intention of vehicle 1 is also taken into account, i.e., its own motion trajectory 18.The system then assesses the criticality posed by the other vehicle 10 to vehicle 1, as well as the criticality based on the current driving and traffic situation. Driver perception is also determined, i.e., whether or not the other vehicle 10 is seen by the driver of vehicle 1. As soon as it is assumed that the other vehicle 10 is obscured and that a potentially critical situation for vehicle 1 arises from it, a warning cascade is triggered, depending on the proximity of the potential accident location and the imminent time of the expected accident. This procedure thus allows the driver of vehicle 1 to be warned of an obscured object 10 that is potentially critical to the safety of vehicle 1. Reference symbol list

[0058] 1 Motor vehicle 2 Road 3 Intersection 4 Tree 5 Detection device 6 Control device 7 Communication device 8 Communication link 10 Other vehicle 11 Radius 12 Detection range 13 Visibility range 16 Vehicle mirror 17 Motion trajectory 18 Self-motion trajectory

Claims

1. Method for warning a driver of a motor vehicle (1), comprising the following steps: - receiving position data of a first object (10), from a vehicle-external communication device (7), by means of a communication device (7) of the motor vehicle (1), - detecting a vehicle environment by means of a detection device (5) of the motor vehicle (1), - detecting an ego position of the motor vehicle (1), - checking whether a second object (4) which obscures the first object (10) is detected by the detection device (5) in a visual range (13) between the motor vehicle (1) and the first object (10), which visual range is determined on the basis of the received position data and the ego position, wherein the first object (10) is located behind the motor vehicle (1) and a visibility of the first object (10) in a vehicle mirror (16) is ascertained, for which purpose a potential imaging region of the first object (10) in the vehicle mirror (16) is determined and it is checked whether the second object (4) which obscures the first object (10) is detected between the imaging region in the vehicle mirror (16) and the first object (10), wherein the imaging region is ascertained on the basis of predetermined imaging properties of the vehicle mirror (16), a position setting of the vehicle mirror (16) and an eye position and / or head position of the driver of the motor vehicle (1) detected by the detection device (5), and the visibility is also ascertained on the basis of the received position data, - checking whether a potentially critical situation for the motor vehicle (1) results from the first object (10), wherein, if the first object (10) is a vehicle, current movement data are received from the first object (10), on the basis of which a potential movement trajectory (17) of the first object (10) is ascertained, and if it is established that this potential movement trajectory (17) intersects with a potential ego movement trajectory (18) of the motor vehicle (1), this is identified as the resulting potential critical situation, wherein the current movement data of the first object (10) provide the motor vehicle (1) with information about a current direction of travel and speed of travel of the first object (10), and / or, in order to check whether the first object (10) results in the potentially critical situation for the motor vehicle (1), an object criticality value quantifying a hazard potential emanating from the first object (10), and a situation criticality value quantifying the hazard potential emanating from a potential traffic situation are ascertained, on the basis of which values the potentially critical situation is assessed, - if the detection device identifies that the first object (10) located behind the motor vehicle (1) is obscured by the second object (4), and the first object (10) results in the potential critical situation for the motor vehicle (1), initiating a predefined warning cascade.

2. Method according to the preceding claim, wherein the motor vehicle (1) only receives position data from the vehicle-external communication device (7) if the communication device and / or the first object (10) is located within a predefined vicinity (11) of the motor vehicle (1).

3. Method according to either of the preceding claims, wherein another vehicle (10) or an infrastructure unit comprises the vehicle-external communication device (7) and is the first object (10).

4. Method according to any of the preceding claims, wherein another vehicle (10) or an infrastructure unit comprises the vehicle-external communication device (7) and detects the first object (10) by means of a sensor unit, and the position data of this detected first object (10) are received by the motor vehicle (1).

5. Method according to any of the preceding claims, wherein map data, in particular 3D map data, are used to check whether the second object (4) which obscures the first object (10) is located in the visual range (13) between the motor vehicle (1) and the first object (10).

6. Method according to any of the preceding claims, wherein, when determining the visual range (13), in addition to the received position data and the ego position, by means of the detection device (5), a line of vision of the driver of the motor vehicle (1) is taken into account and it is checked whether, starting from an origin of vision in the line of vision between the driver and the first object (10), a component of the motor vehicle (1) that obscures the first object (10) is detected.

7. Method according to any of the preceding claims, wherein, if the predefined warning cascade is carried out to an end of the warning cascade, an automatic emergency stop of the motor vehicle (1) is carried out to avoid the development of the potentially critical situation.

8. Control apparatus (6) for a motor vehicle (1) for warning a driver of the motor vehicle (1), comprising means designed to carry out a method according to any of the preceding claims.

9. Motor vehicle (1) comprising a control apparatus (6) according to the preceding claim.