DETERMINING A POTHOLE-AVOIDING TRAJECTORY OF A MOTOR VEHICLE

Abstract

A method for determining a trajectory of a motor vehicle for a driver assistance function includes: determining an initial trajectory of the motor vehicle on a road; setting an upper threshold for the lateral acceleration of the motor vehicle; detecting data of the road surface in the direction of travel ahead of the motor vehicle with at least one sensor; determining the vertical profile of the road surface of a plurality of paths running parallel to each other in the direction of travel ahead of the motor vehicle by using the data; determining, when the vertical profile of at least one of the paths indicates a pothole, a lateral deviation from the initial trajectory for which a limit value does not exceed the set upper threshold for the lateral acceleration, wherein the road boundary is not exceeded; and outputting an adjusted trajectory by using the determined lateral deviation.

Claims

1-16 (canceled)

17. A method for determining a trajectory of a motor vehicle for a driver assistance function, comprising: determining an initial trajectory of the motor vehicle on a road having a road boundary; setting an upper threshold for a lateral acceleration of the motor vehicle; detecting data of a road surface in a direction of travel ahead of the motor vehicle with at least one sensor; determining a vertical profile of the road surface of a plurality of paths running parallel to each other in the direction of travel ahead of the motor vehicle by using the data of the road surface; determining, when the vertical profile of at least one of the paths has a road depression which has defined characteristics for classifying the road depression as a pothole, a lateral deviation from the initial trajectory for which a limit value does not exceed the set upper threshold for the lateral acceleration, wherein the road boundary is not exceeded; and outputting an adjusted trajectory by using the determined lateral deviation.

18. The method of claim 17, including at least partially controlling the motor vehicle using the driver assistance function.

19. The method of claim 17, wherein the at least one sensor for detecting the road surface includes at least one of a camera, a radar sensor, a lidar sensor, an ultrasonic sensor, or a laser sensor.

20. The method of claim 17, wherein the plurality of paths include at least one path arranged in the direction of travel to a right side of a current trajectory of the motor vehicle and at least one path arranged in the direction of travel to a left side of the current trajectory of the motor vehicle.

21. The method of claim 17, wherein the defined characteristics for classifying the road depression as a pothole include at least one of a length, a depth, or a width of the road depression.

22. The method of claim 17, further including: detecting a current speed of the motor vehicle; determining a current distance of the motor vehicle from the pothole; and setting the limit value based on the current speed and the current distance from the pothole.

23. The method of claim 17, wherein, upon determination that the pothole is present in all paths, further including: classifying the pothole in terms of resistance for each path; determining a path with the lowest resistance and a lateral distance of the initial trajectory from this path; and determining the lateral deviation from the initial trajectory in the direction of the determined path.

24. The method of claim 17, wherein, upon determining that the pothole is not present in all paths, further including: determining a shortest lateral distance of the initial trajectory from a path in which there is no pothole, the shortest lateral distance being determined as a lateral deviation when the limit value is not exceeded; and determining a smaller lateral deviation for which the limit value is not exceeded when the limit value is exceeded for the shortest lateral distance as a lateral deviation.

25. The method of claim 24, wherein determining the smaller lateral deviation is based on at least one of a width of a tire of the motor vehicle, a current speed of the motor vehicle, or a current distance of the motor vehicle from the pothole.

26. A computing device for determining a trajectory of a motor vehicle for a driver assistance function and comprising a processor and a memory, the memory storing instructions executable by the processor, the instructions including instructions to: determine an initial trajectory of the motor vehicle on a road having a road boundary; set an upper threshold for a lateral acceleration of the motor vehicle; receive data of a road surface in a direction of travel ahead of the motor vehicle from at least one sensor; determine a vertical profile of the road surface of a plurality of paths running parallel to each other in the direction of travel ahead of the motor vehicle by using the data of the road surface; determine, when the vertical profile of at least one of the paths has a road depression which has defined characteristics for classifying the road depression as a pothole, a lateral deviation from the initial trajectory for which a limit value does not exceed the set upper threshold for the lateral acceleration, wherein the road boundary is not exceeded; and outputting an adjusted trajectory by using the determined lateral deviation.

27. The computing device of claim 26, wherein the instructions to receive data of the road surface include instructions to receive data from at least one of a camera, a radar sensor, a lidar sensor, an ultrasonic sensor, or a laser sensor.

28. The computing device of claim 26, wherein the plurality of paths include at least one path arranged in the direction of travel to a right side of a current trajectory of the motor vehicle and at least one path arranged in the direction of travel to a left side of the current trajectory of the motor vehicle.

29. The computing device of claim 26, wherein the defined characteristics for classifying the road depression as a pothole include at least one of a length, a depth, or a width of the road depression.

30. The computing device of claim 26, wherein the instructions further include instructions to: detect a current speed of the motor vehicle; determine a current distance of the motor vehicle from the pothole; and set the limit value based on the current speed and the current distance from the pothole.

31. The computing device of claim 26, wherein, upon determination that the pothole is present in all paths, the instructions further include instructions to: classify the pothole in terms of resistance for each path; determine a path with the lowest resistance and a lateral distance of the initial trajectory from this path; and determine the lateral deviation from the initial trajectory in the direction of the determined path.

32. The computing device of claim 26, wherein, upon determining that the pothole is not present in all paths, the instructions further include instructions to: determine a shortest lateral distance of the initial trajectory from a path in which there is no pothole, the shortest lateral distance being determined as a lateral deviation when the limit value is not exceeded; and determine a smaller lateral deviation for which the limit value is not exceeded when the limit value is exceeded for the shortest lateral distance as a lateral deviation.

33. The computing device of claim 32, wherein the instructions to determine the smaller lateral deviation use at least one of a width of a tire of the motor vehicle, a current speed of the motor vehicle, or a current distance of the motor vehicle from the pothole.

34. A non-transitory computer-readable storage medium having stored thereon computer-executable instructions to cause a processor to perform operations to: determine an initial trajectory of a motor vehicle on a road having a road boundary; set an upper threshold for a lateral acceleration of the motor vehicle; receive data of a road surface in a direction of travel ahead of the motor vehicle from at least one sensor; determine a vertical profile of the road surface of a plurality of paths running parallel to each other in a direction of travel ahead of the motor vehicle by using the data of the road surface; determine, when the vertical profile of at least one of the paths has a road depression which has defined characteristics for classifying the road depression as a pothole, a lateral deviation from the initial trajectory for which a limit value does not exceed the set upper threshold for the lateral acceleration, wherein the road boundary is not exceeded; and outputting an adjusted trajectory to a driver assistance function by using the determined lateral deviation.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG. 1 shows a schematic top view of a road with a motor vehicle according to an implementation.

[0024] FIG. 2 shows a flow chart of a general variant of a method according to an implementation.

[0025] FIG. 3 shows a flow chart of another variant of a method according to an implementation.

[0026] FIG. 4 shows a motor vehicle according with a driver assistance system according to an implementation.

DETAILED DESCRIPTION

[0027] The figures are not necessarily detailed and true to scale and may be shown enlarged or reduced to provide a better overview. Therefore, functional details disclosed here are not to be understood restrictively, but only as an illustrative basis which provides guidance to the person skilled in this field of technology to use the present invention in a variety of ways.

[0028] The term “and/or” used herein, when used in a series of two or more elements, means that each of the listed elements can be used alone, or any combination of two or more of the listed elements can be used. If, for example, a composition is described which contains the components A, B and/or C, the composition may contain A alone; B alone; C alone; A and B in combination; A and C in combination; B and C in combination; or A, B, and C in combination.

[0029] FIG. 1 shows schematically a motor vehicle 1 according to an implementation, which is moving on a road 4 in a direction of travel marked by the arrow 11 along a trajectory 7. The road 4 has lane boundary lines, in the example shown as an outer lane boundary line 6, and a center line 5.

[0030] The motor vehicle 1 includes a number of sensors 2, including at least one sensor 2 for detecting the road surface 4 in the direction of travel 11. The at least one sensor 2 may be a camera, for example a front camera, and/or a radar sensor and/or a lidar sensor and/or an ultrasonic sensor and/or a laser sensor. By means of at least one sensor 2, the road 4 is detected with regard to road depressions along a plurality of paths 8, 9 running parallel to each other in the direction of travel 11 ahead of the motor vehicle 1. In the example shown, the road is monitored with regard to depressions of the road surface 4 along three paths 8 arranged to the right of an initial trajectory 7 and along three paths 9 arranged to the left of an initial trajectory 7. A right inner path, a right middle, and a right outer path 8 are provided and a left inner path, a left middle and a left outer path 9 are provided. The number of paths and their arrangement relative to each other can be defined individually. The example shown is only an exemplary configuration.

[0031] A general example of a method according to the disclosure for determining a trajectory of a motor vehicle 1 is explained below based on a flowchart of FIG. 2. In step 21, an initial trajectory 7 is first determined for the movement of motor vehicle 1 on a road 4, which has a road boundary 5, 6. In step 22, an upper threshold for permissible lateral acceleration of the motor vehicle 1 is determined. In step 23, the road surface 4 in the direction of travel 11 ahead of the motor vehicle 1 is detected by means of the sensor 2.

[0032] Subsequently, in step 24, the elevation profile or the vertical profile of a plurality of paths 8, 9 running parallel to each other in the direction of travel 11 ahead of the motor vehicle 1 is determined by using the data detected by the sensor 2. In step 25, it is checked whether at least one of the paths has a road depression, which has defined characteristics for classifying the road depression as a pothole. If this is not the case, the method jumps back to step 24. If this is the case, in step 26 a lateral deviation from the initial trajectory is determined for which a limit value formed by means of the specified upper threshold for lateral acceleration is not exceeded and for which the road boundary 5, 6 is not exceeded. Subsequently, in step 27, a trajectory adjusted by using the lateral deviation determined in step 26, i.e., adjusted according to the road surface, is output.

[0033] The grading or classification of a road depression as a pothole can be based on the length or the horizontal extent and/or the depth and/or the vertical extent and/or the width or the lateral extent of the road depression. In a simple design, a pothole can be regarded as detected if a detected road depression exceeds a specified threshold value.

[0034] By using the data detected by the sensor 2, the distance x.sub.prev of the motor vehicle from the pothole, as well as the depth and length of the detected pothole, may be determined for each of the paths considered. Furthermore, the current vehicle speed v.sub.veh may be detected. These data may be taken into account when setting the limit value.

[0035] Another implementation of a method according to the disclosure is explained below on the basis of FIG. 3. The flow chart shown is linked to step 25 of the method described in FIG. 2, i.e., to the case in which a road depression has been detected, which has defined characteristics of a pothole. For such a detected pothole, it is checked in step 31 whether or not it is present in all paths 8, 9 considered.

[0036] If the detected pothole is not present in all the paths considered, as represented by step 32, it is calculated below whether the motor vehicle can be steered to the nearest path in which no pothole is detected without exceeding the specified limit value. For this purpose, in step 33 the distance di.sub.at from the nearest path in which there is no pothole is determined. If in step 34 the determined distance is less than a limit determined according to the following formula, d.sub.lat<0.5*A.sub.thr*(x.sub.prev/v.sub.veh).sup.2, then in step 35 the distance d.sub.lat from the nearest path without a pothole is determined as a lateral deviation and is output as a correspondingly adjusted trajectory. A.sub.thr is the specified upper threshold for the permissible lateral acceleration, x.sub.prev is the distance of the motor vehicle from the detected pothole and v.sub.veh is the vehicle speed.

[0037] The upper threshold of lateral acceleration can be selected from determined vehicle operating modes. For example, in the context of a sporty driving mode, a higher value may be determined for the upper threshold of the lateral acceleration and a lower value for a comfort mode. Thus, if the lateral distance d.sub.lat is less than the calculated limit value determined on the basis of the vehicle speed, the distance of the motor vehicle from the pothole and the specified upper threshold for permissible lateral acceleration, the distance d.sub.lat is added as an offset or displacement to the initial trajectory 7 and thus the detected pothole is bypassed.

[0038] If in step 36 the value d.sub.lat is greater than the calculated limit, i.e. d.sub.lat>0.5*A.sub.thr*(x.sub.prev/v.sub.veh).sup.2, then in step 37 a new lower value for the lateral deviation or offset value d.sub.lat2 is calculated. For example, the formula d.sub.lat2=max((d.sub.lat−0.5*w.sub.tire), (0.5*w.sub.tire)) can be used. w.sub.tire is the width of the tires. The lower offset value d.sub.lat2 is calculated because the motor vehicle cannot travel a trajectory calculated by using the distance d.sub.lat without exceeding the upper limit value for the lateral acceleration. The first part of the calculation formula is the required lateral deviation to move the edges of the wheels along the desired path (d.sub.lat−0.5*w.sub.tire) The second part of the equation calculates the lateral deviation to move half the width of the tire outside the original path (0.5*w.sub.tire). The aim of this calculation is to determine the best possible trajectory in which the pothole is not completely bypassed laterally, but at least half of the tire width is sufficient to prevent the wheel from sinking into the pothole.

[0039] If in step 38 the value d.sub.lat2 can be reached without exceeding the upper threshold for lateral acceleration A.sub.thr, i.e. d.sub.lat2<0.5*A.sub.thr*(x.sub.prev/v.sub.veh).sup.2, in step 39 the value d.sub.lat2 is added to the initial trajectory as a lateral deviation.

[0040] If in step 40 the value d.sub.lat2 cannot be reached without exceeding the upper threshold A.sub.thr, i.e. d.sub.lat2>0.5*A.sub.thr*(x.sub.prev/v.sub.veh).sup.2, a new value for the lateral deviation or displacement or offset value d.sub.lat3 is calculated in step 41, for example using the formula d.sub.lat3=min((d.sub.lat−0.5*w.sub.tire), (0.5*w.sub.tire)). In principle, this is the same as for the calculation of the value d.sub.lat2, wherein the minimum value is used instead of the maximum value. If the value d.sub.lat3 can be reached without exceeding the upper threshold for the lateral acceleration, i.e., 42 applies, then in step 43 this value d.sub.lat3 is added as a lateral displacement or lateral deviation to the initial trajectory 7.

[0041] If in step 44 the value d.sub.lat3 cannot be achieved without exceeding the upper limit for the lateral acceleration, i.e. d.sub.lat3<0.5*A.sub.thr*(x.sub.prev/v.sub.veh).sup.2, no modification of the initial trajectory is made in step 45 . In this case, the required adjustment would cause too much lateral acceleration, which in turn would lead to less acceptance on the part of the user and thus not to an improvement in driving comfort.

[0042] If in step 46 the pothole was detected in all the paths considered, for example in all six paths, 8 and 9, the pothole is classified individually for all paths in step 47. Based on the classification, in step 48 the path with the lowest resistance and the distance d.sub.lat thereof from the initial trajectory 7 is determined. If an improved crossing of the pothole is possible when switching to this path, this path can be selected, wherein in step 49 the maximum possible lateral deflection d.sub.max or the lateral displacement of the vehicle without exceeding the upper threshold for lateral acceleration is determined, for example according to the formula d.sub.max=0.5*A.sub.thr*(x.sub.prev/v.sub.veh).sup.2.

[0043] The sign (i.e., + or −) and thus the direction of the maximum possible lateral displacement d.sub.max is selected depending on the distance between the initial trajectory and the desired path or the desired displacement d.sub.lat. The sign is selected in step 50. The goal is to select the maximum possible offset in the direction of the path with least resistance. This is implemented by equating the sign to the direction. In step 51, the trajectory is modified by means of the value d.sub.max determined in step 50, wherein it is ensured that when the motor vehicle is steered along the modified trajectory, the upper limit for the permissible lateral acceleration A.sub.thr is not exceeded, sign(d.sub.max)=sign(d.sub.lat).

[0044] As part of the method shown in FIG. 3, it is checked at an appropriate point that the modification of the initial trajectory does not exceed the road boundaries. This can be carried out, for example, in the context of steps 35, 39, 43 and 51. The distance of the individual paths and the initial trajectory from the respective road markings 5, 6 can be determined from the data about the road surface 4 detected by means of the sensor 2.

[0045] In an implementation, after the trajectory 7 has been adjusted and the motor vehicle 1 has passed through the pothole, the modification is reversed, i.e. the lateral offset or the lateral deviation added to the initial trajectory in the context of the method is subtracted again and the movement of the motor vehicle 1 is continued on the initial trajectory 7. The adjustment of the trajectory 7 both when adding an offset and when later subtracting the offset to or from the initial trajectory is preferably carried out with a lateral acceleration adjusted according to the respective speed of the motor vehicle in order to achieve a high level of driving comfort and thus a high acceptance of the evasive maneuver on the part of the user.

[0046] FIG. 4 shows schematically a motor vehicle 1 according to the disclosure. The motor vehicle 1 includes a driver assistance system 10. The driver assistance system 10 includes an evaluation device 3, such as a computer, ECU, or other processor with a storage for storing executable instructions. The motor vehicle 1 comprises at least one sensor 2 for detecting the road surface in the direction of travel ahead of the motor vehicle 1. The evaluation device 3 is designed to receive signals from the sensor 2. This is indicated by an arrow.

REFERENCE CHARACTER LIST

[0047] 1 Motor vehicle [0048] 2 Sensor [0049] 3 Evaluation device [0050] 4 Road [0051] 5 Center line [0052] 6 Outer road boundary line [0053] 7 Trajectory [0054] 8 Path [0055] 9 Path [0056] 10 Driver assistance system [0057] 11 Direction of travel [0058] 21 Determining an initial trajectory [0059] 22 Determining an upper threshold for the lateral acceleration of the motor vehicle [0060] 23 Detection of the road surface in the direction of travel [0061] 24 Determining the vertical profile of the road surface of a plurality of paths running parallel to each other in the direction of travel ahead of the motor vehicle by using the data collected by the sensor [0062] 25 Does the vertical profile of at least one of the paths have a pothole? [0063] 26 Determining a lateral deviation from the initial trajectory, for which a limit value formed by means of the specified upper threshold for the lateral acceleration is not exceeded, and for which the road boundary is not exceeded [0064] 27 Outputting an adjusted trajectory [0065] 31 Pothole detected in all paths? [0066] 32 Pothole not present in all considered paths [0067] 33 Potholes present in all considered paths [0068] 34 d.sub.lat<0.5*A.sub.thr*(x.sub.prev/v.sub.veh).sup.2 [0069] 35 Determine the distance to the nearest path without a pothole as a lateral deviation [0070] 36 d.sub.lat>0.5*A.sub.thr*(x.sub.prev/v.sub.veh).sup.2 [0071] 37 Calculate the lower value for the lateral deviation d.sub.lat2 [0072] 38 d.sub.lat2<0.5*A.sub.thr*(x.sub.prev/v.sub.veh).sup.2 [0073] 39 add d.sub.lat2 as the lateral deviation to the initial trajectory [0074] 40 d.sub.lat2>0.5*A.sub.thr*(x.sub.prev/v.sub.veh).sup.2 [0075] 41 Calculate the lower value for the lateral deviation d.sub.lat3 [0076] 42 d.sub.lat3<0.5*A.sub.thr*(x.sub.prev/v.sub.veh).sup.2 [0077] 43 Add d.sub.lat3 as the lateral deviation to the initial trajectory [0078] 44 d.sub.lat3>0.5*A.sub.thr*(x.sub.prev/v.sub.veh).sup.2 [0079] 45 No modification of the initial trajectory [0080] 46 Potholes in all considered paths [0081] 47 Classify potholes for all paths individually [0082] 48 Determine the path with the lowest resistance and the lateral distance thereof from the initial trajectory d.sub.lat [0083] 49 Determine the maximum possible lateral deviation [0084] 50 Choose the sign [0085] 51 Adjust the trajectory [0086] N no [0087] J yes