Method and device for avoiding a collision of a vehicle with an oncoming vehicle

Abstract

A method for avoiding a collision of a vehicle (50) with an oncoming vehicle (60), comprising the following steps: Detecting an environment (40) of the vehicle (50) by means of a sensor system (2), estimating and detecting a risk of collision with an oncoming vehicle (60) on the basis of detected environment data (41) by means of an estimation device (3), Carrying out an evasive maneuver (5) when a risk of collision is detected by controlling a lateral and longitudinal control (53) of the vehicle (50) by means of a control (4), characterized in that when selecting and carrying out the evasive maneuver (5), an acceleration (6) acting when carrying out the evasive maneuver (5) is taken into account.

Description

The invention relates to a method and a device for avoiding a collision of a vehicle with an oncoming vehicle.Devices for avoiding a collision of a vehicle with an oncoming vehicle are known. In these, an avoidance maneuver is carried out on the basis of an estimated collision probability. Estimating the collision probability or detecting a risk of collision with a vehicle in oncoming traffic is subject to a great uncertainty on account of a generally high relative speed of the vehicles with respect to one another and on account of unpredictable driving maneuvers of the oncoming vehicle. In particular, a collision risk may increase or decrease within the time considered in the context of the estimation depending on a behavior of the oncoming vehicle.DE 10 2009 034 386 A1 discloses a driving assistance device for a vehicle which carries out an avoidance maneuver in order to avoid a collision if the risk of collision is detected. DE 101 28 792 A1 discloses a device which, after a collision risk is detected in time-critical situations, directly engages in a controller of the vehicle.From DE 10 2009 012 226 A1, a method for preventing or reducing the following of a collision of a vehicle with an obstacle is known, having the steps: detecting an environmental variable characterizing the obstacle by means of a sensor device, detecting a driving dynamics variable of the vehicle characterizing a driving state of the vehicle, ascertaining a triggering condition, which is dependent on the environmental variable and the driving dynamics variable, for triggering a warning indicating an imminent collision of the vehicle with the obstacle or for triggering a full braking for collision avoidance or collision reduction. In order to enable an earliest possible warning or full braking with a minimum error frequency, it is provided that the triggering condition for the warning or full braking is additionally dependent on a characteristic variable which is dependent on a speed of the vehicle.DE 10 2008 022 606 A1 discloses a method for guiding a commercial vehicle on a roadway, wherein a driver assistance system guides the vehicle within the roadway in a predefined lane and a navigation system contributes the course of the roadway guidance. When the vehicle approaches an obstacle that impairs the width of the roadway and / or when the roadway guidance changes to a curve, a configuration of the driver assistance system allows the vehicle to deviate from the lane by active steering measures or by steering interventions by the driver. After passing the obstacle and / or at the exit of the curve, the vehicle is returned to the driving lane again.The object of the invention is to provide a method and a device for avoiding a collision of a vehicle with an oncoming vehicle, in which the performance of an avoidance maneuver can be improved, in particular more comfortable for vehicle occupants.The object is achieved according to the invention by a method with the features of claim 1 and a device with the features of claim 10. Advantageous embodiments of the invention are evident from the dependent claims.In particular, a method for avoiding a collision of a vehicle with an oncoming vehicle is provided, comprising the following steps: detecting an environment of the vehicle by means of a sensor system, estimating and detecting a risk of collision with an oncoming vehicle on the basis of detected environmental data by means of an estimating device, carrying out an avoidance maneuver when detecting a risk of collision by actuating a lateral and longitudinal control of the vehicle by means of a controller, wherein an acceleration acting when carrying out the avoidance maneuver is taken into account when selecting and carrying out the avoidance maneuver.Furthermore, in particular, a device for avoiding a collision of a vehicle with an oncoming vehicle is provided, comprising a sensor system for detecting an environment of the vehicle, an estimating device for estimating and detecting a risk of collision with an oncoming vehicle on the basis of detected environment data, and a controller for carrying out an avoidance maneuver when detecting a risk of collision by actuating a lateral and longitudinal control of the vehicle, wherein the controller is designed to select and carry out the avoidance maneuver in such a way that an acceleration acting when carrying out the avoidance maneuver is taken into account.The advantage of the invention is that the avoidance maneuver is selected and carried out as a function of an acceleration acting on vehicle occupants. An acceleration is intended to refer in particular to a transverse acceleration acting on vehicle occupants. However, it can also be provided to additionally take into account a longitudinal acceleration acting on the vehicle occupants. By taking into account the acceleration, comfort during carrying out the avoidance maneuver can be increased, in particular if large accelerations or large changes in acceleration can be prevented as a result.The sensor system comprises, for example, a camera and / or a radar device and / or a lidar device and / or an ultrasonic device, with which the environment and, in particular, an oncoming vehicle in the environment can be detected and associated environment data can be provided for further evaluation. In particular, a position and a speed of the oncoming vehicle are detected or determined by means of the sensor system. If further oncoming vehicles are present, these are also correspondingly detected.For calculating the risk of collision, the estimating device can estimate, for example, a future trajectory of the vehicle and a future trajectory of the oncoming vehicle. This is done, for example, on the basis of a detected position and a specific speed of the oncoming vehicle and a position and a speed of the vehicle. On the basis of the trajectories, the vehicles are guided along the trajectories, for example, as rectangles or as circles covering an outer contour of the vehicle, such that in each case a travel path in which the vehicles will in each case move can be predicted. If an overlap of the rectangle or the circles of the vehicle with the rectangle or with the circles of the oncoming vehicle along the trajectories or an overlap of the driving hoses is detected, a risk of collision is detected. This procedure is repeated continuously with current environmental data supplied by the sensor system. Alternatively, probability distributions can also be used to determine a collision or a collision probability. If a collision probability exceeds a predefined threshold value, a risk of collision is ascertained. In addition to the aforementioned methods, other suitable methods for determining the collision probability can also be used in principle.The selection of the avoidance maneuver comprises, in particular, a definition or planning of an avoidance trajectory. For this purpose, for example, mutually linked positions are defined on a road which the vehicle is intended to drive along at a specific point in time after the avoidance maneuver has been started. On the basis of speed information respectively linked to the trajectory or the individual positions, an acceleration, in particular a transverse acceleration, acting on the vehicle when traversing the trajectory can be determined.In the simplest case, the avoidance maneuver consists of a simple steering movement to the side. The avoidance maneuver here comprises, in particular, driving up or approaching an outer roadway boundary. This is carried out in particular in the form of an S-shaped trajectory, that is to say the trajectory comprises a first steering operation in the direction of the edge of the roadway and a subsequent further steering operation in order to align the vehicle parallel to the roadway again. In the case of right-hand traffic, this means a driving to a right-hand side of the roadway, and in the case of left-hand traffic, a driving to a left-hand side of the roadway accordingly. It can be provided here that a speed is reduced, but this does not have to be the case. After passing the oncoming vehicle, the vehicle can be returned to the center of the roadway by a reverse steering movement. In particular, an avoidance maneuver should not be an emergency maneuver with which a collision in time-critical situations is prevented, but rather should enable a predictive intervention for averting a potential collision risk while maintaining the greatest possible driving comfort. In the avoidance maneuver, it is provided in particular that certain specifications are taken into account, for example that a roadway marking on the roadway edge must not be traveled over in the case of steering interventions (e.g. emergency steering function, ESF) (as is provided, for example, in the control UN / ECE R 79).It can be provided that additionally also emergency avoidance maneuvers are provided, which prevent a collision in time-critical cases.Parts of the apparatus, in particular the estimating device and the controller, can be configured individually or collectively as a combination of hardware and software, for example as program code which is executed on a microcontroller or microprocessor.In one specific embodiment, it is provided that the avoidance maneuver and a point in time for starting the avoidance maneuver or a distance from the oncoming vehicle at which the avoidance maneuver is started are selected or are selected such that the acceleration acting during the avoidance maneuver is below a maximum acceleration. In particular, this makes it possible to realize early intervention and execution of the avoidance maneuver with low accelerations. The method aims at reacting a collision risk at an early stage. The avoidance maneuver or an avoidance trajectory can then be configured such that an acceleration that occurs, in particular an occurring transverse acceleration, is below the maximum acceleration at any point in time during the avoidance maneuver. Comfort for the vehicle occupants can be increased as a result, in particular in cases in which the avoidance maneuver was triggered, even though a collision risk no longer occurred at a later point in time.In a development, it is provided that a value for the maximum acceleration can be specified. For example, it can be provided that the maximum acceleration, in particular for a transverse acceleration, should be not greater than 1 m / s 2 or 0.5 m / s 2. For example, it can be provided that a driver of the vehicle specifies a maximum acceleration, for example by input into the controller or into an onboard computer of the vehicle. This allows individual preferences of the driver or other vehicle occupants to be taken into account. It can also be provided here that maximum acceleration profiles stored in the controller or in the onboard computer can be selected, which depending on the magnitude of an associated maximum acceleration can be divided into the categories "low", "normal" and "high", for example.In one specific embodiment, it is furthermore provided that the time for starting the avoidance maneuver may be predefined at least within a time range. By presetting a point in time lying within the time range, the execution of the avoidance maneuver can be shifted temporally, in particular forwards, that is to say the avoidance maneuver is then already executed at an earlier point in time. As a result, an acceleration occurring during the avoidance maneuver, in particular a transverse acceleration, can be further reduced by adapting the avoidance trajectory, as a result of which the comfort for the vehicle occupants is further increased. The latest possible time in the time range is defined here by the avoidance maneuver with the greatest possible acceleration. For example, it can be provided that within a time range between 3 and 10 seconds before the estimated collision time, it is possible to freely choose when the avoidance maneuver is started. If a longer time is selected, an acceleration acting during the avoidance maneuver, in particular an acting transverse acceleration, can be reduced, since more time is available for carrying out the avoidance maneuver and, in particular, steering maneuvers can be carried out more slowly.In a further embodiment, it is provided that the distance can be predetermined at least within a distance range. By presetting a distance lying within this distance range, the execution of the avoidance maneuver can be shifted with respect to a relative distance, in particular to a greater distance. As a result, an acceleration occurring during the avoidance maneuver can be reduced, whereby the comfort for the vehicle occupants is further increased. The smallest possible distance in the distance range is defined here by the avoidance maneuver with the greatest possible acceleration. For example, it can be provided that within a distance range between 50 and 100 meters in front of the estimated collision location, the avoidance maneuver can be freely selected, where it is started. If a greater distance is selected, an acceleration acting during the avoidance maneuver, in particular an acting transverse acceleration, can be reduced.In a further embodiment, it is provided that a lane marking distance to a lane marking, which cannot be undershot by the vehicle when performing the avoidance maneuver, can be predefined at least within a lane marking distance range, wherein the lane marking distance is taken into account when selecting and / or performing the avoidance maneuver. This allows a further individual preference of the driver to be taken into account, as a result of which comfort in the case of non-time-critical avoidance can be further increased if the risk of collision is detected. In particular for drivers who are uncomfortable with a lane marking distance that is too small, this creates the possibility of further enhancing comfort even when changing.In one specific embodiment, it is provided that a speed of the vehicle and / or a speed of the oncoming vehicle is taken into account when selecting and / or when carrying out the avoidance maneuver. In this way, the avoidance maneuver can also be adapted to a relative speed resulting from the speeds. In particular, it can be provided that a time at which the execution of the avoidance maneuver is started or a distance at which the execution of the avoidance maneuver is started is adapted as a function of the speed of the vehicle and / or the speed of the oncoming vehicle. A greater relative speed then leads in particular to a starting of the avoidance maneuver at an earlier point in time or at a greater distance from the oncoming vehicle.In a further embodiment, it is provided that a visual, acoustic and / or haptic warning message is output by means of a warning device before and / or while the avoidance maneuver is being carried out. By outputting the warning message, the driver and the vehicle occupants are warned or prepared prior to and / or during the intervention carried out for carrying out the avoidance maneuver in a longitudinal and / or lateral control, so that the intervention does not come unexpectedly. This also leads to an increase in comfort.In one specific embodiment, it is provided that a visual, acoustic, and / or haptic warning message is output by means of a warning device if the avoidance maneuver is not possible to be carried out. This warning message is output in particular in situations in which an avoidance is not possible at all, since, for example, no area for avoidance is present. This can be triggered by a narrow road guidance or by appropriately predefined driver preferences, such as a large road marking distance. In this case, the risk of collision is pointed out in good time, so that the driver can react to this in good time and can take appropriate measures.The invention is explained in more detail below on the basis of a preferred exemplary embodiment with reference to the single figure. This shows FIG. 1 is a schematic illustration of an embodiment of the apparatus for avoiding a collision of a vehicle with an oncoming vehicle and a typical situation on a country road to illustrate the invention.In FIG. 1, a schematic representation of an embodiment of the device 1 for avoiding a collision of a vehicle 50 with an oncoming vehicle 60 and a typical situation on a country road 20 are shown. The apparatus 1 is disposed in, for example, the vehicle 50 traveling in a direction on a lane 21 of the land road 20. On the other lane 22, the vehicle 50 is approached by an oncoming vehicle 60 which also travels at least partially on the lane 21 of the vehicle 50.The device 1 comprises a sensor system 2, an estimation device 3 and a controller 4. the sensor system 2 detects an environment 40 of the vehicle 50 and provides environment data 41. By means of the sensor system 2, in particular, oncoming vehicles 60 are detected and recognized. The estimating device 3 estimates a risk of collision of the vehicle 50 with an oncoming vehicle 60 on the basis of the captured environment data 41. for this purpose, a future trajectory 51 or a driving path 52 based on the trajectory 51 and a vehicle outer contour is estimated and compared with a future trajectory 61 or a driving path 62 based thereon of the oncoming vehicle 60. In the case of an overlap 30 of the trajectories 51, 61 or of the driving hoses 52, 62, a risk of collision and an associated collision time 42 and an associated collision location 43 are determined. The estimator 3 supplies the collision time 42 and the collision location 43 to the controller 4. The controller 4 executes an avoidance maneuver 5 by controlling a lateral and longitudinal control 53 of the vehicle 50.The controller 4 selects the avoidance maneuver 5 in this case or executes it in such a way that an acceleration 6 acting during the execution of the avoidance maneuver 5, in particular an acting transverse acceleration, is taken into account. The selection comprises, for example, the generation of at least one avoidance trajectory 7. On the basis of the at least one avoidance trajectory 7, the controller 4 can determine the acting acceleration 6, in particular the acting transverse acceleration, at any point in time of the avoidance maneuver 5.It can be provided that the avoidance maneuver 5 and a time 8 for starting the avoidance maneuver 5 or a distance 9 from the oncoming vehicle 60, at which the avoidance maneuver 5 is started, are selected or are selected such that the acceleration 6 acting during the avoidance maneuver 5, in particular the acting transverse acceleration, is below a maximum acceleration 31. This allows early and predictive avoidance, in which vehicle occupants of vehicle 50 experience only an acceleration, in particular a transverse acceleration, which is below maximum acceleration 31.It can be provided here that a value for the maximum acceleration 31 can be predefined. This can be done, for example, on a display and operating device 54 of the vehicle 50. A driver of the vehicle 50 can then set the desired maximum acceleration 31 at the display and operating device 54.Furthermore, it can be provided that the time 8 for starting the avoidance maneuver 5 can be predefined at least within a time range 10. The time 8 can likewise be set, for example, on the display and operating device 54 as a driver preference.Furthermore, it can be provided that the distance 9 can be predetermined at least within a distance range 11. The distance 9 can likewise be set, for example, on the display and operating device 54 as a driver preference.It can be provided that a road marking distance 12 from a road marking 13, which cannot be undershot by the vehicle 50 when performing the avoidance maneuver 5, can be predefined at least within a road marking distance range 14, wherein the road marking distance 12 is taken into account when selecting and / or performing the avoidance maneuver 5. In particular, the controller 4 selects or generates an avoidance trajectory 7 in which the lane marking distance 12 is not undershot.It can further be provided that a speed of the vehicle 50 and / or a speed of the oncoming vehicle 60 is taken into account when selecting and / or when carrying out the avoidance maneuver 5. In particular, it can be provided that a time at which the execution of the avoidance maneuver is started or a distance at which the execution of the avoidance maneuver is started is adapted as a function of the speed of the vehicle and / or the speed of the oncoming vehicle.It can furthermore be provided that the apparatus 1 comprises a warning device 15 and that an optical, acoustic and / or haptic warning message 16 is output by means of the warning device 15 before and / or during the avoidance maneuver 5 is carried out.It can furthermore be provided that a visual, acoustic and / or haptic warning message 16 is output by means of a warning device 15 of the device 1 if the avoidance maneuver 5 cannot be carried out.List of reference characters1 Device 2 Sensor system 3 Estimation device 4 Controller 5 Avoidance maneuver 6 Acceleration 7 Avoidance trajectory 8 Point in time 9 Distance 10 Time range 11 Distance range 12 Lane marking distance 13 Lane marking 14 Lane marking distance range 15 Warning device 16 Warning message 20 Road 21 Lane 22 Other lane 30 Overlap 31 Maximum acceleration 40 Environment 41 Environment data 42 Collision point in time 43 Collision location 50 Vehicle 51 Trajectory 52 Driving tube 53 Lateral and longitudinal regulation 54 Display and operator control device 60 Oncoming vehicle 61 Trajectory 62 Driving tube

Claims

Method for avoiding a collision of a vehicle (50) with an oncoming vehicle (60), comprising the following steps: detecting an environment (40) of the vehicle (50) by means of a sensor system (2), estimating and detecting a risk of collision with an oncoming vehicle (60) on the basis of detected environmental data (41) by means of an estimating device (3), carrying out an avoidance maneuver (5) when detecting a risk of collision by actuating a lateral and longitudinal control (53) of the vehicle (50) by means of a controller (4), characterized in that an acceleration (6) acting when carrying out the avoidance maneuver (5) is taken into account when selecting and carrying out the avoidance maneuver (5).Method according to Claim 1, characterized in that the avoidance maneuver (5) and a time (8) for starting the avoidance maneuver (5) or a distance (9) from the oncoming vehicle (50) at which the avoidance maneuver (5) is started are selected or are selected such that the acceleration (6) acting during the avoidance maneuver (5) is below a maximum acceleration (31).Method according to Claim 2, characterized in that a value for the maximum acceleration (31) can be predefined.Method according to either of Claims 2 and 3, characterized in that the time (8) for starting the avoidance maneuver (5) can be predefined at least within a time range (10).Method according to one of Claims 2 to 4, characterized in that the distance (9) can be predefined at least within a distance range (11).Method according to one of the preceding claims, characterized in that a road marking distance (12) from a road marking (13), which cannot be undershot by the vehicle (50) when carrying out the avoidance maneuver (5), can be predefined at least within a road marking distance range (14), wherein the road marking distance (12) is taken into account when selecting and / or carrying out the avoidance maneuver (5).Method according to one of the preceding claims, characterized in that a speed of the vehicle (50) and / or a speed of the oncoming vehicle is taken into account when selecting and / or when carrying out the avoidance maneuver (5).Method according to one of the preceding claims, characterized in that an optical, acoustic and / or haptic warning message (16) is output by means of a warning device (15) before and / or during the avoidance maneuver (5) is carried out.Method according to one of the preceding claims, characterized in that an optical, acoustic and / or haptic warning message (16) is output by means of a warning device (15) if the avoidance maneuver (5) is not possible to be carried out.Device (1) for avoiding a collision of a vehicle (50) with an oncoming vehicle (60), comprising: a sensor system (2) for detecting an environment (40) of the vehicle (50), an estimating device (3) for estimating and detecting a risk of collision with an oncoming vehicle (60) on the basis of detected environmental data (41), and a controller (4) for carrying out an avoidance maneuver (5) when detecting a risk of collision by actuating a lateral and longitudinal control (54) of the vehicle (50), characterized in that the controller (4) is designed in such a way that the avoidance maneuver (5) is selected and carried out in such a way that an acceleration (6) acting when carrying out the avoidance maneuver (5) is taken into account.

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