METHOD FOR OPERATING A VEHICLE IN AN AUTOMATED DRIVING OPERATION

Description

[0001] The invention relates to a method for operating a vehicle in an automated driving mode according to the preamble of patent claim 1.

[0002] DE 10 2017 011 808 A1 discloses a method for controlling the movement of a vehicle in automated driving mode and a device for carrying out the method. The method provides for the automated driving mode to be switchable from a regular operating mode, in which the vehicle is automatically guided to a predetermined target position, to an emergency operating mode, in which the vehicle is automatically guided to an emergency stop position. Control in regular operating mode is carried out by a main control unit, and in emergency operating mode by a secondary control unit. Automated driving mode is switched from regular operating mode to emergency operating mode if a functional impairment of the main control unit is detected in regular operating mode.Control in regular operating mode is carried out based on a regular target trajectory leading to the target position, which is continuously determined by the main control unit in regular operating mode. Control in emergency operating mode is carried out based on an emergency operating target trajectory stored in the secondary control unit and leading to the emergency stop position, which was determined by the main control unit in regular operating mode before the operating mode was switched to emergency operating mode and fed to the secondary control unit for storage. In regular operating mode, in addition to the emergency operating target trajectory, a lane profile of a lane traveled by the vehicle, associated with the emergency operating target trajectory, is also determined and fed to the secondary control unit for storage. Furthermore, it is provided that the emergency operating target trajectory and the associated lane profile are determined in a vehicle-fixed coordinate system of the main control unit.In emergency operation mode, the lane path of the lane traveled by the vehicle is determined in a vehicle-fixed coordinate system of the secondary control unit and in emergency operation mode, based on the lane path of the lane stored in the secondary control unit and the lane path of the lane determined by the secondary control unit, a deviation between the coordinate systems of the main control unit and the secondary control unit is compensated and thus a correction of the stored emergency operation target trajectory is carried out.

[0003] The invention is based on the object of specifying a method for operating a vehicle in automated driving mode.

[0004] The object is achieved according to the invention by a method which has the features specified in claim 1.

[0005] Advantageous embodiments of the invention are the subject of the subclaims.

[0006] A method for operating a vehicle in an automated, in particular highly automated or driverless, driving mode provides that the vehicle is automatically guided to a target position in a regular operating mode of the automated driving mode by means of a main control unit and is automatically guided along an emergency operation target trajectory to a safe stopping position in an emergency operating mode of the automated driving mode by means of a secondary control unit,The emergency operation target trajectory is continuously determined in regular operating mode by means of the main control unit and stored in the secondary control unit together with a preceding lane profile of a vehicle's lane continuously detected using lane markings. In emergency operating mode, a correction of the stored emergency operation target trajectory is made based on the stored lane profile and a lane profile of the vehicle's lane continuously determined in emergency operating mode. According to the invention, in emergency operating mode, a deviation between the stored lane profile and the lane profile continuously determined in emergency operating mode is determined. Depending on the determined deviation, an assessment is made as to whether the continuously determined lane profile is plausible.and that the correction of the stored emergency operation target trajectory based on the stored lane path and the continuously determined lane path is only performed if the continuously determined lane path has been assessed as plausible. The continuously determined lane path in emergency operation mode corresponds to the currently determined lane path in emergency operation mode.

[0007] In emergency operation mode, a decision is made depending on the deviation determined as to whether the continuously determined lane course, i.e. the currently determined lane course, should be taken into account when guiding the vehicle to the safe stopping position or should be ignored or rejected.

[0008] By applying this method, particularly by correcting the stored emergency target trajectory based on the plausibility check of the continuously determined lane path, the risk of incorrectly detected vehicle lanes being used for guidance can be reduced. If the lane path is implausible, the comparatively reliable emergency operation target trajectory can then be followed using so-called dead reckoning data.

[0009] One embodiment of the method provides that, in emergency mode, the continuously determined lane path is assessed as plausible if the determined deviation falls below a specified value. Otherwise, if the continuously determined lane path exceeds the specified value, the lane path is assessed as implausible and discarded, and the vehicle is then guided to the safe stopping position according to the stored emergency target trajectory.

[0010] In particular, the method is used when camera track information in comparatively complex scenarios produces incorrect results, which can be identified and thus circumvented using the method.

[0011] Furthermore, the method can significantly reduce the risk of the vehicle leaving its lane and the resulting increased risk of an accident, not only for the vehicle itself but especially due to incorrectly detected lane markings.

[0012] In addition, the method can be used to verify the plausibility of environmental detection data from an environmental sensor system in a main control unit for automated driving of the vehicle.

[0013] In a further development of the method, the deviation between the stored lane path and the continuously determined lane path is determined by determining the deviation between the stored lane path and the continuously determined lane path at a given distance in front of the vehicle. This makes it possible to easily determine a measure of the deviation.

[0014] In a possible further development, the specified distance is set based on speed, with the distance being set to be greater at higher speeds than at a comparatively lower speed. This makes it possible to react to possibly incorrectly detected lane markings in a speed-adapted manner.

[0015] A possible embodiment of the method provides that the correction of the stored emergency operation target trajectory is carried out by comparing the stored track course with the continuously determined track course.

[0016] To compare the stored track profile with the continuously determined track profile, it is preferably determined which coordinate transformation needs to be applied to the stored track profile in order to adapt the stored track profile to the continuously determined track profile. This means that the extent to which the stored track profile, and thus its coordinate system, needs to be rotated and shifted in order to achieve a match between the stored track profile and the continuously determined track profile is determined.

[0017] To correct the stored emergency target trajectory, the determined coordinate transformation is applied to the stored emergency target trajectory. The result of this coordinate transformation is the corrected emergency target trajectory.

[0018] In another possible embodiment of the method, the vehicle is located in emergency mode using dead reckoning if lane markings required to determine the lane path are not detected, or if the lane path is detected but assessed as implausible. In particular, localization is performed using dead reckoning data, which is used to operate the vehicle in emergency mode, so that the vehicle can be brought to a safe stop position.

[0019] In a further possible embodiment, the lane markings are continuously determined using image data, in particular a vehicle camera and / or another suitable device, in order to move the vehicle into the safe stopping position in the activated emergency operating mode.

[0020] Embodiments of the invention are explained in more detail below with reference to a drawing.

[0021] The following shows: Fig. 1 schematically shows a vehicle driving on a lane of a road section in automated driving mode.

[0022] The single figure shows a road section F with two opposing lanes F1, F2 and a vehicle 1 driving in a right lane F1 in automated driving mode.

[0023] In a regular operating mode of automated, particularly highly automated, driving, the vehicle 1 is localized by a main control unit 2 using satellite and landmark support. The main control unit 2 determines a target trajectory, representing a driving specification, at regular intervals in a vehicle-fixed coordinate system and executes trajectory control according to the determined target trajectory. The target trajectory comprises a description of a path along which the vehicle 1 is to be moved in regular operating mode. Furthermore, the target trajectory comprises a description of a speed profile at which the vehicle 1 is to move along the path.

[0024] The vehicle 1 comprises an environmental sensor system 3, which has a vehicle camera 4 and lidar-based, radar-based, and / or ultrasound-based detection units (not shown in detail). Based on image data acquired by the vehicle camera 4 and signals acquired by the detection units, the environment of the vehicle 1 and objects located therein are detected.

[0025] Based on the acquired image data and the signals detected by the environmental sensor system 3, an environmental situation is detected, including the lane path of the lane F1 of vehicle 1, i.e., the lane path of the right lane F1. The lane path is determined by detecting lane markings S that delimit the lane F1.

[0026] The target trajectory along which the vehicle 1 moves in the regular operating mode of automated driving is determined based on the recorded environmental situation, taking into account the recorded lane course and the lane information determined from a digital map.

[0027] At the same time, during the determination of the target trajectory, an emergency operation target trajectory is determined at regular intervals, which is also created based on the environmental situation detected by means of the acquired image data, taking into account the recorded lane course and lane information from the digital map in the vehicle-fixed coordinate system.

[0028] The emergency operation target trajectory comprises a description of an emergency path along which the vehicle 1 is transferred to a safe stopping position, also referred to as a safe standstill position, in the event of a failure of the main control unit 2 and / or another vehicle-related fault, for example, a failure of detection units of the environmental sensor system 3, while the emergency operation mode is activated. This safe stopping position is located, for example, at the edge of the right lane F1 or on a hard shoulder, if present.

[0029] In addition, the emergency operation target trajectory includes a description of a course of a speed or acceleration with which the vehicle 1 is to be guided along the emergency path into the holding position, i.e. into a standstill.

[0030] The emergency operation target trajectory is thus a data set that contains a description of the emergency path on which the vehicle is to be moved and a description of the dynamics with which the vehicle is to be moved along the emergency path.

[0031] The emergency operation target trajectory determined at regular intervals and the lane path determined thereby, in particular the determined lane markings S, are fed to a secondary control unit 5, for example, a control unit of a vehicle dynamics control device, and stored there for later use in emergency operation mode. The secondary control unit 5 thus contains a description of the course of the emergency path relative to the lane markings S, with data of the emergency operation target trajectory and the lane path being regularly updated through the regular determination and storage of the emergency operation target trajectory and the lane path.

[0032] This secondary control unit 5, as a redundancy to the main control unit 2, comprises only a limited number of detection units for lateral vehicle guidance in emergency mode. In highly automated driving mode, the secondary control unit 5 receives image data acquired by the vehicle camera 4 with lane detection and dead reckoning data. Lane information determined from the image data, in particular the lane markings S delimiting the right lane F1, is usually correct; however, the image data regarding the lane markings S can yield erroneous results in comparatively complex scenarios.

[0033] In order to identify and correct such erroneous results, a procedure is provided as described below.

[0034] In the event of a failure of the main control unit 2 and / or another error case that restricts the regular operating mode of the automated driving operation, the system switches from the regular operating mode to the emergency operating mode.

[0035] When switching to the emergency operation mode, the secondary control unit 5 takes over the control of the vehicle 1 and guides the vehicle into the safe stopping position by means of trajectory control based on the stored emergency operation target trajectory.

[0036] In emergency mode, the lane markings S are continuously determined based on the image data captured by the vehicle camera 4 in order to continuously determine the lane path of the traffic lane F1. The continuously determined lane path, i.e., the currently determined lane path, is compared with the stored lane path. In particular, any deviation between a coordinate system of the stored lane path and a coordinate system of the determined lane markings S is determined and corrected.

[0037] The correction is performed by rotating and shifting the coordinate system of the stored track path until the stored track path matches the currently determined track path. This coordinate correction also corrects the emergency path path.

[0038] In particular, to determine the deviation between the stored and currently determined lane path, a distance x is specified, so that the deviation of the stored lane path from the currently determined lane path is determined at a position at the specified distance x in front of the vehicle 1. The distance x is specified in particular as a function of speed, whereby the distance x is greater at a higher speed of the vehicle 1 than at a lower speed.

[0039] At the distance x to the vehicle 1, the deviation between the stored lane path and the currently determined lane path is determined in front of the vehicle 1.

[0040] If it is determined in a next step of the procedure that this deviation falls below a specified value in meters, the currently determined lane course is assessed as plausible and used to correct the stored emergency target trajectory and the trajectory control is carried out according to the corrected emergency operation target trajectory.

[0041] If, however, it is determined that the deviation between the stored lane path and the currently determined lane path exceeds the specified value in meters, the currently determined lane path is assessed as implausible, and no correction is made to the emergency operation target trajectory. The stored emergency target trajectory then continues to be used unchanged as the basis for trajectory control.

Claims

1. Method for operating a vehicle (1) in an automated driving operation, wherein the vehicle is guided in an automated manner to a target position by means of a main control unit (2) in a regular operating mode of the automated driving operation, and is guided in an automated manner along an emergency operation target trajectory into a safe stopping position by means of a secondary control unit (5) in an emergency operating mode of the automated driving operation, wherein the emergency operation target trajectory is continuously determined in the regular operating mode by means of the main control unit (2), and is stored in an auxiliary control unit (4) together with a lane course of a lane (F1) ahead of the vehicle (1), which lane course is continuously detected using lane markings (S), and wherein, in the emergency operating mode, a correction of the stored emergency operation target trajectory is carried out based on the stored lane course and a lane course of the lane (F1) of the vehicle (1) that is continuously determined in the emergency operating mode, wherein - a deviation between the stored lane course and the continuously determined lane course is continuously detected in the emergency operating mode, characterized in that - depending on the determined deviation, it is assessed whether the continuously determined lane course is plausible, and - the correction of the stored emergency operation target trajectory based on the stored lane course and the continuously determined lane course is only carried out if the continuously determined lane course has been assessed as plausible.

2. Method according to claim 1, characterized in that, in the emergency operation mode, the continuously determined lane course is assessed as plausible if the determined deviation falls below a specified value.

3. Method according to either claim 1 or claim 2, characterized in that the determined deviation is a deviation between the stored lane course and the continuously determined lane course, which occurs at a specified distance (x) in front of the vehicle (1).

4. Method according to claim 3, characterized in that the distance (x) is specified on the basis of the speed.

5. Method according to any of the preceding claims, characterized in that the stored emergency operation target trajectory is corrected by comparing the stored lane course with the continuously determined lane course.

6. Method according to claim 5, characterized in that, in order to compare the stored lane course with the continuously determined lane course, it is determined which coordinate transformation is to be applied to the stored lane course in order to adapt the stored lane course to the continuously determined lane course.

7. Method according to claim 6, characterized in that, in order to correct the stored emergency operation target trajectory, the determined coordinate transformation is applied to the stored emergency operation target trajectory.

8. Method according to any of the preceding claims, characterized in that the vehicle (1) is located in the emergency operating mode by means of dead reckoning if lane markings (S) for determining the lane course are not detected or if the continuously determined lane course has been assessed as implausible.

9. Method according to any of the preceding claims, characterized in that the lane markings (S) are continuously determined based on image data.