Procedures and driver assistance systems

Abstract

Method for changing lanes of a motor vehicle (1) before a lane narrowing (15) of a roadway (14) from a first lane (13) of the roadway (14) to a second lane (16) of the roadway (14), wherein the lane narrowing (15) is detected, and wherein, based on a speed-dependent passing characteristic curve (K1) and based on a speed-dependent distance control characteristic curve (K2), it is determined whether either a passing phase to pass a side lane object (9, 10, 11) traveling on the second lane (16) is initiated with the aid of a passing speed control (19) or whether a distance control phase to follow the side lane object (9, 10, 11) traveling on the second lane (16) is initiated with the aid of a distance control (21).

Description

The invention relates to a method for changing lanes of a motor vehicle before a narrowing of the lane of a roadway from a first lane of the roadway to a second lane of the roadway, as well as a driver assistance system which is designed to carry out the method. In adaptive cruise control (ACC) mode, situations frequently arise where lanes merge into one. A driver assistance system should automatically react to traffic in an adjacent lane, mimicking the behavior of a manually driven vehicle. Map data or traffic sign recognition can detect an impending lane merge. However, depending on map quality, it can be difficult to distinguish which lane ends. Currently, the system either doesn't react to a lane merge or only initiates a lane change search at higher speeds. The system then tries to find a gap between two vehicles. However, at lower speeds, a gap is often not found. German patent application DE 10 2016 204 096 B4 discloses a method for operating a driver assistance system in which the end of a lane can be used to determine that the driver is highly likely to change lanes. This could be the case, for example, at the end of an acceleration lane or at a narrowing of the roadway, such as at a construction site. German patent DE 10 2018 208 910 A1 describes a method for improving traffic flow of vehicles in lanes, particularly when driving through lane narrowings or obstructions. This involves exchanging data on the position of the lane narrowing and at least driving parameters between at least two vehicles traveling in the opposite direction to the narrowing or obstruction. Furthermore, the speeds of the two vehicles are coordinated and adjusted to a target speed for driving through the narrowing or obstruction. Before a lane change, the two vehicles are positioned offset relative to each other in different lanes, and at least one vehicle is steered, or prompted to steer, from a closed lane to an open lane while maintaining a constant speed. It is an object of the present invention to provide a possibility for a motor vehicle to change lanes before a lane narrowing of a roadway. This problem is solved by the subject matter of the independent claims. Advantageous further developments and preferred embodiments are the subject matter of the dependent claims. The invention is based on the idea of ​​determining, using a speed-dependent passing characteristic curve and a speed-dependent distance control characteristic curve, whether a passing phase is initiated using a passing speed control or a distance control phase is initiated using a distance control. According to one aspect of the invention, a method for changing lanes of a motor vehicle from a first lane to a second lane before a lane narrowing of a roadway is described. In this method, the lane narrowing is detected, and a speed-dependent passing characteristic curve and a speed-dependent distance control characteristic curve are used to determine whether a passing phase is initiated to overtake an object traveling in the second lane using a passing speed control curve, or whether a distance control phase is initiated to follow the object traveling in the second lane using a distance control curve. The lane-changing procedure advantageously enables the generation of natural vehicle behavior in ACC operation, since the vehicle either passes the adjacent lane object or follows it based on the speed-dependent passing characteristic curve and the speed-dependent distance control characteristic curve. The method is preferably carried out using a driver assistance system of the motor vehicle. The motor vehicle, and in particular the driver assistance system, preferably has environmental sensors that detect the area around the motor vehicle and thus also the object in the adjacent lane. For example, the environmental sensors can include one or more cameras and / or one or more radar systems and / or one or more lidar systems and / or one or more ultrasonic sensor systems, and the like. The lane narrowing can be detected with the help of the environmental sensors. The procedure is carried out particularly in ACC mode. The passing phase and the distance control phase are preferably initiated or executed depending on the distance between the vehicle and the lane narrowing. Any number of secondary lane objects can be provided. In this context, a "secondary lane object" is understood to be any vehicle, in particular a motor vehicle, that is traveling in the second lane. In the passing phase, the motor vehicle overtakes the secondary lane object. In the distance control phase, the motor vehicle follows the secondary lane object. If the secondary lane object brakes, for example, the vehicle can switch from the distance control phase to the passing phase. Subsequently, it can switch back from the passing phase to the distance control phase.This change occurs depending on the distance to the lane narrowing, based on the speed-dependent passing characteristic curve and the speed-dependent distance control characteristic curve. According to at least one embodiment, the passing phase is initiated first, and the distance control phase is initiated after the passing phase has been initiated. The vehicle reaches an initial distance of, for example, 400 m to the lane narrowing, which triggers a threshold for activating the overtaking phase, in other words, an adjusted overtaking speed. The vehicle then overtakes the adjacent vehicle at the aforementioned overtaking speed. As the vehicle passes the adjacent vehicle, a second distance is automatically reached, triggering the distance control phase. This second distance is smaller than the first. This means that the vehicle is approaching the lane narrowing. During the distance control phase, the vehicle merges into the lane with a small gap behind the adjacent vehicle. According to at least one embodiment, an impending lane change from the first lane to the second lane is signaled to the adjacent lane object during or after the initiation of the distance control phase. For example, the vehicle's turn signal can be automatically activated to indicate the upcoming lane change. According to at least one embodiment, after initiating the distance control phase, the passing phase is initiated again if the adjacent lane object decelerates. This allows for the most natural behavior possible, as the motor vehicle does not follow the adjacent lane object when it decelerates, but overtakes it. According to at least one embodiment, the distance control phase is initiated again after the passing phase has been restarted. In other words, after overtaking the object in the adjacent lane, the motor vehicle follows another object in the adjacent lane. According to at least one embodiment, the passing phase is initiated as soon as the motor vehicle has approached the lane narrowing to a speed-dependent first distance, wherein the distance control phase is initiated as soon as the motor vehicle has approached the lane narrowing to a speed-dependent second distance, and wherein the first distance is greater than the second distance. The passing phase and the distance control phase are thus initiated depending on the distance to the lane narrowing. Additionally, the passing phase and the distance control phase are initiated depending on the speed-dependent passing characteristic curve and the speed-dependent distance control characteristic curve. According to at least one embodiment, when the motor vehicle approaches the lane narrowing below the second distance, the passing phase is initiated again if the adjacent lane object decelerates. In other words, depending on the speed-dependent passing characteristic curve and the speed-dependent distance control characteristic curve, it is possible to switch arbitrarily from the passing phase to the distance control phase and vice versa. According to at least one embodiment, the passing phase is initiated by reducing the speed of the motor vehicle to a passing speed, wherein the passing speed is a sum of the speed of the adjacent lane object and a predetermined passing speed difference. This allows for an adjusted overtaking speed. This enables natural vehicle behavior in ACC mode. According to a further aspect of the invention, a driver assistance system for a motor vehicle is provided. The driver assistance system is configured to perform a lane change of the motor vehicle from a first lane of the roadway to a second lane of the roadway before a lane narrowing. The driver assistance system is configured to detect the lane narrowing and to determine, based on a speed-dependent passing characteristic curve and a speed-dependent distance control characteristic curve, whether the driver assistance system initiates a passing phase to overtake an object traveling in the second lane using a passing speed control function, or whether the driver assistance system initiates a distance control phase to follow the object traveling in the second lane using a distance control function. The driver assistance system is used in particular to carry out the procedure described above. According to at least one embodiment, the driver assistance system has an environment sensor for detecting the environment of the motor vehicle and a data processing unit, wherein the environment sensor is configured to detect the lane narrowing and / or the adjacent lane object, and wherein the data processing unit is configured to determine, on the basis of the speed-dependent passing characteristic curve and on the basis of the speed-dependent distance control characteristic curve, whether the driver assistance system initiates the passing phase or the distance control phase. The speed-dependent passing characteristic curve and the speed-dependent distance control characteristic curve can be stored in the data processing unit. Further features of the invention will become apparent from the claims, the figures, and the description of the figures. The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and / or shown in the figures alone, are not only usable in the combinations specified, but also in other combinations or on their own. The invention will now be explained in more detail with reference to a preferred embodiment and the drawings. Figure 1 shows a schematic top view of a motor vehicle; and Figure 2 shows a schematic view of a procedure for changing lanes of the motor vehicle according to Figure 1. Figure 1 schematically shows an exemplary embodiment of a motor vehicle 1 with a driver assistance system 2. The motor vehicle 1 can be, in particular, a semi-autonomous or autonomous vehicle 1, for example, corresponding to Level 2, Level 3, Level 4, or Level 5 according to the classification in SAE J3016. The motor vehicle 1 can operate in ACC mode (Adaptive Cruise Control). However, the motor vehicle 1 can also be driven manually. The driver assistance system 2 has a human-machine interface 3, by means of which the driver assistance system 2 can communicate with a driver of the motor vehicle 1 and vice versa. The human-machine interface 3 can be a screen, in particular a touchscreen, or may have such a screen. The driver assistance system 2 may also have a data processing unit 4. The driver assistance system 2 is assigned an environmental sensor system 5 for detecting or recognizing the environment 6 of the vehicle 1. For example, the environmental sensor system 5 can include one or more cameras and / or one or more radar systems and / or one or more lidar systems and / or one or more ultrasonic sensor systems, and the like. The environmental sensor system 5 can include any type of sensor. The environmental sensor system 5 can provide sensor data to the driver assistance system 2. The driver assistance system 2 can evaluate this sensor data, for example, with the help of the data processing unit 4, and draw conclusions about the environment 6. The motor vehicle 1 or the driver assistance system 2 may have a navigation system 7 and / or a communication interface 8. Using the communication interface 8, for example, vehicle-to-vehicle messages can be received from other road users or vehicle-to-vehicle messages can be sent to other road users. For example, the motor vehicle 1 can use the communication interface 8 to communicate with other motor vehicles 9, 10, 11 that are in the vicinity of the motor vehicle 1 and / or that are at least partially within the monitored environment 6. Motor vehicle 1 is traveling in a direction 12 along lane 13 of a roadway 14 towards a lane merging or narrowing 15 of the roadway 14. The roadway 14 has two lanes and thus includes, in addition to lane 13, another lane 16, on which motor vehicles 9, 10, and 11 are traveling. Before the lane narrowing 15, motor vehicle 1 must change from lane 13 to lane 16 and merge between motor vehicles 9, 10, and 11. This is referred to as a "lane merge" or lane change. Accordingly, a "lane merging" or "lane narrowing" in this context refers to a merging or narrowing of the roadway 14 from two lanes 13 and 16 to one lane 16. Motor vehicles 9, 10, 11 are secondary lane objects for motor vehicle 1 and can therefore also be described as such. In ACC mode, when vehicle 1 approaches lane narrowing 15, the driver assistance system 2 must react to vehicles 9, 10, and 11 in lane 16. The system should simulate human-like behavior. It is known that an upcoming lane narrowing 15 can be detected using map data or sign recognition. However, depending on the map quality, it is difficult to distinguish which of the lanes 13 and 16 ends. Currently, the system does not react to such lane merges, or only initiates a lane change search at higher speeds. Instead, it searches for a gap between two vehicles 9, 10, and 11. However, particularly at low speeds, a gap cannot be found. Figure 2 shows a schematic procedure for a lane change of motor vehicle 1 from lane 13 to lane 16 before the lane narrowing 15. The speed v of motor vehicle 1 in km / h is plotted on the horizontal axis, and the distance a to the lane narrowing 15 in m is plotted on the vertical axis. In Figure 2, a first characteristic curve or passing characteristic curve K1 is shown with a dashed line, and a second characteristic curve or distance control characteristic curve K2 is shown with a dashed line. The movement of motor vehicle 1 itself is indicated by a solid line. If the lane narrowing 15 is detected by the driver assistance system 2, the two speed-dependent characteristic curves K1 and K2 are used to determine whether distance control (i.e., a distance control phase) is already being actively initiated for one of the vehicles 9, 10, or 11, or whether an adapted overtaking maneuver (i.e., a passing phase) is being initiated. If the passing phase is initiated, vehicle 1, for example, moves at a speed v equal to the object speed of the respective vehicle 9, 10, or 11 plus a speed of, for example, 20 km / h, in order to complete the overtaking maneuver. The characteristic curves K1 and K2 can be such that they overlap in order to generate a reducible and natural behavior using simple means. The characteristic curves K1 and K2 are shown as straight lines in Fig. 2.However, the characteristic curves K1 and K2 can, in principle, have any desired shape. A specific example is explained below using Fig. 2. Motor vehicle 1 initially travels freely 17 towards the lane narrowing 15. Lane 13 ends, while lane 16 continues. The speed v, in particular a settling speed, of motor vehicle 1 in lane 13 is 130 km / h. Motor vehicles 9, 10, and 11 in lane 16 are already traveling more slowly, for example, at 100 km / h. Motor vehicle 1 reaches an initial distance a1 of, for example, 400 m to the lane narrowing 15, which triggers a threshold for activating the overtaking phase, in other words, an adjusted overtaking speed. The speed v of motor vehicle 1 is thereby reduced, for example, to 120 km / h. This 120 km / h results from the speed of 100 km / h of an object in the adjacent lane, namely one of the motor vehicles 9, 10, or 11 in lane 16, plus a 20 km / h overtaking difference parameter. In Fig. 2, the overtaking phase is triggered at a point 18. A overtaking speed control is then implemented, as indicated by reference numeral 19 in Fig. 2. By overtaking vehicles 9, 10, and 11, a second distance a2 is automatically reached, triggering the previously mentioned distance control 21. This second distance a2 is smaller than the first distance a1. In Fig. 2, the distance control 21 is triggered at point 20. The overtaking speed control 19 ends at point 20. At point 20, vehicle 1 transitions to a lane-keeping control and merges into the lane with a small gap behind one of the vehicles 9, 10, or 11. There are now two scenarios. In the first scenario, each of the vehicles 9, 10, and 11 maintains its speed. In this case, vehicle 1 remains "stubbornly" behind its target, namely one of the vehicles 9, 10, or 11, at a small distance, which can be 20% to 50% of a normal following distance. Additionally, vehicle 1 signals to the following traffic in lane 16 that it is ready to change lanes. This could be done, for example, by activating a turn signal. In a second scenario, shown in Fig. 2, the vehicle in the adjacent lane, one of the vehicles 9, 10, or 11, must brake because a traffic jam is already forming in lane 16. Lane 13 for vehicle 1 is clear, but it would be too early to merge, as the zipper merge procedure only allows merging shortly before the lane narrowing 15. Vehicle 1 brakes because it is actively adjusting its speed to the vehicle in the adjacent lane, one of the vehicles 9, 10, or 11. This causes the distance control characteristic curve K2 to be exceeded again at point 22, triggering the overtaking speed control 19. The system repeatedly switches to the passing phase, namely an overtaking maneuver at an adjusted speed, until the distance control characteristic K2 is again undershot at point 23. As soon as point 23 is undershot, the distance control is reactivated. A passing maneuver occurs between point 18 and point 20. Distance control is again activated between point 20 and point 22. Another passing maneuver occurs between point 22 and point 23, and from point 23 to the end, distance control is again activated. At point 23, the distance control characteristic K2 is again undershot, and the system adjusts to the nearest adjacent lane object, in the form of one of the vehicles 9, 10, or 11. A distance rule 21 is now in effect again. This means that vehicle 1 is again following a neighboring vehicle in the form of one of the vehicles 9, 10, or 11. By consistently selecting a neighboring vehicle at a very short distance, for example, by positioning itself 2 meters behind the bumper, the intention to change lanes is clearly signaled to following traffic, and generally enough space is left for merging into lane 16. Reference symbol list 1 Motor vehicle 2 Driver assistance system 3 Human-machine interface 4 Data processing unit 5 Environmental sensors 6 Environment 7 Navigation system 8 Communication interface 9 Motor vehicle / adjacent lane object 10 Motor vehicle / adjacent lane object 11 Motor vehicle / adjacent lane object 12 Direction of travel 13 Lane 14 Roadway 15 Lane narrowing 16 Lane 17 Clear passage 18 Point 19 Pass-by speed control 20 Point 21 Distance control 22 Point 23 Point a Distance a1 Distance a2 Distance K1 Pass-by characteristic curve K2 Distance control characteristic curve v Speed

Claims

Method for changing lanes of a motor vehicle (1) before a lane narrowing (15) of a roadway (14) from a first lane (13) of the roadway (14) to a second lane (16) of the roadway (14), wherein the lane narrowing (15) is detected, and wherein, based on a speed-dependent passing characteristic curve (K1) and based on a speed-dependent distance control characteristic curve (K2), it is determined whether either a passing phase to pass a side lane object (9, 10, 11) traveling on the second lane (16) is initiated with the aid of a passing speed control (19) or whether a distance control phase to follow the side lane object (9, 10, 11) traveling on the second lane (16) is initiated with the aid of a distance control (21). Method according to claim 1, wherein the pass-by phase is initiated first, and wherein the distance control phase is initiated after the pass-by phase has been initiated. Method according to claim 2, wherein, at or after the initiation of the distance control phase, the adjacent lane object (9, 10, 11) is signaled an impending lane change from the first lane (13) to the second lane (16). Method according to claim 2 or 3, wherein after initiating the distance control phase the passing phase is initiated again if the adjacent lane object (9, 10, 11) decelerates. Method according to claim 4, wherein after the re-initiation of the passing phase, the distance control phase is initiated again. Method according to any one of claims 1 to 5, wherein the passing phase is initiated as soon as the motor vehicle (1) has approached the lane narrowing (15) to a speed-dependent first distance (a1), wherein the distance control phase is initiated as soon as the motor vehicle (1) has approached the lane narrowing (15) to a speed-dependent second distance (a2), and wherein the first distance (a1) is greater than the second distance (a2). Method according to claim 6, wherein when the motor vehicle (1) approaches the lane narrowing (15) below the second distance (a2), the passing phase is initiated again if the adjacent lane object (9, 10, 11) decelerates. Method according to any one of claims 1 to 7, wherein the pass-by phase is initiated by reducing the speed (v) of the motor vehicle (1) to a pass-by speed, and wherein the pass-by speed is a sum of the speed of the adjacent lane object (9, 10, 11) and a predetermined pass-by speed difference. Driver assistance system (2) for a motor vehicle (1), wherein the driver assistance system (2) is configured to perform a lane change of the motor vehicle (1) before a lane narrowing (15) of a roadway (14) from a first lane (13) of the roadway (14) to a second lane (16) of the roadway (14), wherein the driver assistance system (2) is configured to detect the lane narrowing (15), and wherein the driver assistance system (2) is configured to determine, on the basis of a speed-dependent passing characteristic curve (K1) and on the basis of a speed-dependent distance control characteristic curve (K2), whether the driver assistance system (2) should either use a passing speed control (19) to initiate a passing phase for passing an adjacent lane object (9, 10) traveling in the second lane (16).11) initiates or whether the driver assistance system (2) initiates a distance control phase to follow the adjacent lane object (9, 10, 11) traveling in the second lane (16) using a distance control (21). Driver assistance system according to claim 9, wherein the driver assistance system (2) comprises an environment sensor (5) for detecting an environment (6) of the motor vehicle (1) and a data processing unit (4), wherein the environment sensor (5) is configured to detect the lane narrowing (15) and / or the adjacent lane object (9, 10, 11), and wherein the data processing unit (4) is configured to determine, on the basis of the speed-dependent passing characteristic curve (K1) and on the basis of the speed-dependent distance control characteristic curve (K2), whether the driver assistance system (2) initiates the passing phase or the distance control phase.

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