Method and device for setting the travel speed of a vehicle

Abstract

The invention relates to a device for defining the value of the target speed of a driving function for the automated longitudinal and / or transverse guidance of a vehicle. The device is configured to determine the reference gaze direction of the driver of the vehicle for monitoring the driving function, and to determine the actual gaze direction of the driver. The device is furthermore configured to determine the value of the target speed of the driving function based on the gaze direction deviation between the actual gaze direction and the reference gaze direction and based on a predefined functional relationship between the gaze direction deviation and the target speed.

Description

[0001] 24-3291

[0002] - 1 -

[0003] Method and device for adjusting the driving speed of a vehicle

[0004] The invention relates to a method and a corresponding device designed to effect automated longitudinal and / or lateral guidance of a vehicle.

[0005] A vehicle may have one or more driving functions (especially driver assistance systems) that are each designed to automate longitudinal and / or lateral movement of the vehicle. Depending on the degree of automation, particularly the SAE level, the driver of the vehicle is typically still required to monitor the operation of the driving function.

[0006] This document addresses the technical challenge of enabling particularly convenient and reliable monitoring of the operation of a driving function for automated longitudinal and / or lateral guidance of a vehicle.

[0007] The problem is solved by each of the independent claims. Advantageous embodiments are described, inter alia, in the dependent claims. Es24-3291

[0008] - 2 -

[0009] It is pointed out that additional features of a patent claim dependent on an independent patent claim, without the features of the independent patent claim itself or only in combination with a subset of the features of the independent patent claim, can constitute a separate invention independent of the combination of all features of the independent patent claim, which can be made the subject of an independent claim, a divisional application, or a subsequent application. This applies equally to technical teachings described in the description, which can constitute an invention independent of the features of the independent patent claims.

[0010] According to one aspect, a device for setting the target speed of a driving function for automated longitudinal and / or lateral control of a (motor) vehicle is described. The driving function can be configured to adjust the automated longitudinal control of the vehicle using a speed controller, wherein the speed controller can be configured to adjust, and in particular regulate, the longitudinal speed depending on the current target speed. The current target speed can be used as the setpoint for speed control.

[0011] The device is designed to determine (for any given time) the driver's optimal viewing direction for monitoring the vehicle's driving function. In other words, it can determine the driver's ideal viewing direction for monitoring the driving function.

[0012] The device can be configured to determine (for the current time) a future driving trajectory for operating the driving function for automated longitudinal and / or lateral control of the vehicle. The driving trajectory can be determined (based on sensor data from one or more 24-3291

[0013] - 3 -

[0014] The vehicle's environmental sensors may have been used to plan the trajectory using a trajectory planning method. Furthermore, automated longitudinal and / or lateral guidance can be achieved to follow the (planned) preceding trajectory. A trajectory tracking controller can be used for this purpose.

[0015] The device can be configured to determine the desired viewing direction based on the vehicle's trajectory. The desired viewing direction can be determined, for example, based on a point on the trajectory. This point can be located, for example, at a specific distance (e.g., one meter or more) in front of the vehicle in the direction of travel.

[0016] The device can further be configured to determine the driver's current gaze direction (for the present moment), e.g., based on sensor data from one or more of the vehicle's driver sensors. The device can also be configured to determine a large number of measurements related to the driver's gaze direction based on sensor data from at least one driver sensor. The driver's current gaze direction can then be determined in a particularly robust manner based on this large number of measurements, especially based on a frequency distribution of these measurements.

[0017] Furthermore, the device is configured to determine the target speed of the driving function (for the current time) depending on the deviation of the actual viewing direction from the desired viewing direction and depending on a predefined functional relationship between the viewing direction deviation and the target speed. This functional relationship can be predefined and stored on a memory unit in the vehicle. The functional relationship can specify a target speed value for a multitude of different values ​​of the viewing direction deviation. 24-3291

[0018] - 4 -

[0019] The functional relationship preferably exhibits a maximum value for a gaze direction deviation of zero, where the actual gaze direction corresponds to the desired gaze direction. Furthermore, the functional relationship is preferably designed such that the value of the target speed specified by the relationship decreases (increasingly) with increasing absolute value of the gaze direction deviation.

[0020] The gaze direction deviation can include an azimuth component, related to the azimuth angle (relative to the intended gaze direction), and an altitude component, related to the altitude angle of the gaze direction (relative to the intended gaze direction). The functional relationship can specify a target velocity value for a multitude of different combinations of azimuth and altitude component values.

[0021] The device can be configured to operate the speed controller (at the current time) depending on the determined target speed value in order to effect automated longitudinal and / or lateral control of the vehicle.

[0022] This allows the driver of a vehicle to efficiently and conveniently set the target speed of a driving function for automated longitudinal and, if applicable, lateral control. This increases the comfort and safety of the automated longitudinal and, if applicable, lateral control of the vehicle.

[0023] The device can be configured to determine, for a sequence of successive time points, the target viewing direction and the actual viewing direction for each respective time point. Furthermore, the device can be configured to determine the viewing direction deviation for each time point and using the functional 24-3291.

[0024] - 5 -

[0025] The system determines the target speed for each given time. This allows the target speed to be repeatedly, and especially periodically (e.g., every 100 ms or more, or every 20 ms or more), adjusted to the driver's current gaze pattern. This enables consistently comfortable and safe automated longitudinal and, if necessary, lateral control of the vehicle.

[0026] The device can be configured to adapt its functional relationship to the prevailing driving situation. In particular, the maximum target speed can be adjusted. The maximum target speed can be determined, for example, based on the set speed for the vehicle's cruise control, which is defined by the driver via a user interface. Alternatively or additionally, the maximum target speed can be determined based on sensor data from one or more of the vehicle's environmental sensors. Alternatively or additionally, the maximum target speed can be determined based on the (planned) upcoming trajectory of the vehicle, whereby the trajectory is used by the driving function for automated longitudinal and / or lateral control of the vehicle (e.g., as a setpoint for a trajectory tracking controller).The maximum speed can be adjusted, particularly depending on the curvature of the vehicle's trajectory. This further enhances the comfort and safety of the automated longitudinal and / or lateral vehicle guidance.

[0027] According to another aspect, a method for determining the target speed value of a driving function for automated longitudinal and / or lateral control of a (motor) vehicle is described. The method includes determining a target viewing direction for the driver of the vehicle to monitor the driving function. The target viewing direction can correspond to the viewing direction that 24-3291

[0028] - 6 -

[0029] the driver should have (at the respective time) in order to monitor the driving function (in an optimal manner).

[0030] Furthermore, the procedure includes determining the driver's current gaze direction (at the respective time). The procedure also includes determining the target speed of the driving function as a function of the deviation of the current gaze direction from the desired gaze direction and as a function of a predefined functional relationship between the gaze direction deviation and the target speed. The determined target speed can be used (at the respective time) as a target for the automated longitudinal and / or lateral control of the vehicle.

[0031] It should be noted that the aspects described in connection with the device, in particular the claims described in connection with the device, are also applicable to the method as corresponding process features.

[0032] Another aspect described is a software (SW) program. The SW program can be configured to run on a processor (e.g., on a vehicle's control unit) and thereby execute the procedure described in this document.

[0033] Another aspect describes a storage medium. This storage medium can include a software program configured to run on a processor and thereby execute the procedure described in this document.

[0034] In this document, the term "automated driving" refers to driving with automated longitudinal and / or lateral control. Automated driving can, for example, involve a longer period of time.24-3291

[0035] - 7 -

[0036] This could involve driving on the highway or time-limited driving during parking maneuvers. The term "automated driving" encompasses automated driving at any level of automation. Examples of automation levels include assisted, semi-automated, highly automated, fully automated, and autonomous driving (each with increasing levels of automation). The five automation levels mentioned above correspond to SAE Levels 1 to 5 of the SAE J3016 standard (SAE - Society of Automotive Engineering). In assisted driving (SAE Level 1), the system performs longitudinal or lateral control in certain driving situations. In semi-automated driving (SAE Level 2), the system takes over longitudinal and lateral control in certain driving situations, but the driver must continuously monitor the system, as with assisted driving.In highly automated driving (SAE Level 3), the system takes over longitudinal and lateral control in certain driving situations without the driver needing to constantly monitor the system; however, the driver must be able to take over control of the vehicle within a certain timeframe if requested by the system. In fully automated driving (SAE Level 4), the system takes over control of the vehicle in certain driving situations, even if the driver does not respond to a request to intervene, thus eliminating the driver as a fallback option. In autonomous driving (SAE Level 5), the system can perform all aspects of the dynamic driving task under any road and environmental conditions that a human driver can also handle.

[0037] The measures described in this document relate in particular to a driving function that is trained according to SAE Level 3 or less, especially according to SAE Level 2 or less.

[0038] It should be noted that the methods, devices and systems described in this document, both alone and in combination with other methods, devices and systems described in this document, 24-3291

[0039] - 8 -

[0040] can be used. Furthermore, any aspects of the methods, devices, and systems described in this document can be combined with one another in a variety of ways. In particular, the features of the claims can be combined with one another in a variety of ways. Furthermore, features listed in parentheses are to be understood as optional features.

[0041] The invention will now be described in more detail using exemplary embodiments.

[0042] Figure 1 shows exemplary components of a vehicle;

[0043] Figure 2a shows an exemplary functional relationship between the target speed of the vehicle and the direction of the driver's gaze;

[0044] Figure 2b shows an exemplary distribution of the driver's viewing direction;

[0045] Figures 3a and 3b show exemplary driving situations of the vehicle; and

[0046] Figure 4 shows a flowchart of an exemplary procedure for controlling the driving speed of a vehicle.

[0047] As stated at the outset, this document deals with the safe and comfortable operation of a driving function, in particular a driver assistance system, for the automated longitudinal and / or lateral control of a vehicle. In this context, Fig. 1 shows an exemplary vehicle 100 with one or more environmental sensors 102, each configured to acquire sensor data (also referred to as environmental data) relating to the vehicle 100's surroundings. Examples of environmental sensors 102 include a camera, a radar sensor, a lidar sensor, an ultrasonic sensor, etc.

[0048] A (control) device 101 of the vehicle 100 can be configured to evaluate environmental data, e.g., to detect one or more objects (e.g., other vehicles and / or lane markings) in the vicinity of the vehicle 100. The device 101 can further be configured to effect automated longitudinal and / or lateral guidance of the vehicle 100 based on the environmental data, in particular based on the one or more detected objects. 24-3291

[0049] - 9 -

[0050] For this purpose, one or more longitudinal and / or lateral guidance actuators 103 (e.g. a drive motor, a braking device and / or a steering device) of the vehicle can be controlled.

[0051] The automatic longitudinal guidance of vehicle 100 can be achieved, for example, by a speed and / or distance control system. In this case, when driving freely without a vehicle ahead, the vehicle speed can be automatically set to a target speed (possibly defined by the driver via the user interface 105). Furthermore, when following another vehicle, the actual distance between vehicle 100 and a vehicle directly in front of it can be determined based on environmental data. This actual distance can be adjusted, and in particular regulated, to a predefined target distance by the distance control system. The target distance can be set by the driver, for example, via the user interface 105 of vehicle 100.

[0052] The driver of vehicle 100 may still be required to monitor the vehicle's operation when a driving function for automated longitudinal and / or lateral control is in use. Furthermore, it may be desirable for the driver of vehicle 100 to conveniently set the vehicle's speed when the driving function is active. This document describes measures that enable convenient and safe monitoring and / or control of a driving function for automated longitudinal and / or lateral control of vehicle 100. In particular, it may be possible to set and / or adjust the vehicle's speed, especially the target speed of the vehicle's cruise control, based on the driver's gaze, particularly their direction of view. 24-3291

[0053] - 10 -

[0054] The vehicle 100 can include at least one driver sensor 106 configured to acquire sensor data relating to the driver, in particular regarding the driver's gaze direction. The driver sensor 106 can include one or more cameras directed towards the driver's position within the vehicle 100. The control device 101 can be configured to determine gaze information relating to the driver's actual gaze direction based on the sensor data from the one or more driver sensors 106 of the vehicle 100.

[0055] To monitor the operation of vehicle 100, the driver should keep their gaze directed towards the area in front of vehicle 100 in the direction of travel. The control device 101 can be configured to determine a target viewing direction for the driver. For example, the control device 101 can be configured (based on environmental data acquired by one or more environmental sensors 102) to determine the vehicle 100's upcoming trajectory. The target viewing direction can be determined based on the upcoming trajectory, for example, based on a point along that trajectory.

[0056] Furthermore, the control device 101 can be configured to determine the vehicle speed 100, in particular the target speed of the speed controller, depending on how well the actual (actual) direction of view of the driver (which is determined on the basis of the sensor data of the one or more driver sensors 106) corresponds to the target direction of view.

[0057] Fig. 2a shows an exemplary, predefined, functional relationship 200 between the driver's direction of view and the vehicle speed 202 of the vehicle 100 (in particular, the target speed of the cruise control). The relationship 200 can have a maximum value 205 for the vehicle speed 202 if the 24-3291

[0058] - 11 -

[0059] The actual (i.e., the current) viewing direction 201 corresponds to the target viewing direction 206. The maximum value 205 of the driving speed 202 can correspond to the set speed defined by the driver via the user interface 205.

[0060] Furthermore, the relationship 200 can be configured such that the value of the driving speed 202 decreases increasingly sharply from the maximum value 205 as the deviation 201 of the actual viewing direction 216 from the target viewing direction 206 increases. As shown in Fig. 2a, the driving speed 202 can have a reduced speed value 215 if the actual viewing direction 216 deviates from the target viewing direction 206 by a certain deviation value 201. The value of the driving speed 202 can be reduced with increasing deviation 201 of the viewing direction down to a minimum value, which may be zero.

[0061] The device 101 can thus be configured to determine the driver's actual (i.e., current) gaze direction 216 at a specific time during the operation of the driver assistance system for automated longitudinal and / or lateral guidance, based on the sensor data from one or more driver sensors 106. Furthermore, the device 101 can be configured to determine the target gaze direction 206 at that specific time (e.g., based on environmental data). Based on the deviation 201 of the actual gaze direction 216 from the target gaze direction 206, the value 215 of the target speed 202 of the vehicle 100 for that specific time can be determined using the (predefined) functional relationship 200. The speed controller of the driving function can then be operated with the (reduced) value 215 of the target speed 202 (possibly instead of the set speed defined by the driver).

[0062] Similarly, for a sequence of successive time points, the viewing direction present at each respective time point can be determined.-24-3291

[0063] - 12 -

[0064] Deviation 201 and, based on this, using the relationship 200, the value 215 of the target speed 202 for the respective time can be determined. This allows the driver to control the vehicle's speed 100 comfortably and safely by looking in the direction of travel. Furthermore, this enables particularly safe operation of a driving function for automated longitudinal and / or lateral control.

[0065] The driver's gaze direction is typically not permanently fixed on a specific point, but changes over time. The device 101 can be configured to determine a statistical distribution 210 of the frequency 212 of the different gaze directions 211 within a specific period of time, based on the sensor data from one or more driver sensors 106 (see Fig. 2b). The period of time can, for example, extend from the current time into the past. Based on the frequency distribution 210, the actual gaze direction 216 for the current time can then be determined in a particularly robust manner, for example, as the mean and / or the center of the distribution 210. Similarly, by using a sliding time window, the actual gaze direction 216 can be determined for a sequence of successive time points.

[0066] Fig. 3a shows an exemplary driving situation in which the vehicle 100 is driving on a roadway 300 and entering a curve. The control device 101 can be configured to determine an upcoming driving trajectory 306 for the vehicle 100 entering the curve based on the environmental data. Based on the driving trajectory 306, a target viewing direction 206 for the driver's view as the vehicle 100 enters the curve can be determined. Similarly, for a sequence of successive time points, an updated driving trajectory 306 and, based on this, an updated target viewing direction 206 can be determined. 24-3291

[0067] - 13 -

[0068] Figure 3b shows an exemplary driving situation in which vehicle 100 approaches an intersection 310 where it intends to turn right (this can be determined, for example, based on a route planned via the vehicle 100's navigation system). Based on environmental data and / or a digital map of the road network traveled by vehicle 100, a future driving trajectory 306 for the turning maneuver can be determined. Furthermore, based on the driving trajectory 306, a target viewing direction 206 for the turning maneuver can be determined. As explained above, the driving trajectory 306 and the target viewing direction 206 can be updated at a sequence of successive time points during the execution of the driving maneuver, particularly during the turning maneuver itself.

[0069] This allows the driver to control the vehicle's speed 202 in dynamic situations by adjusting their gaze and / or head position. For example, if the driver keeps their eyes on the road while turning, the system accelerates to a speed 205 that is appropriate for the geometry of the driving situation. Looking in the direction of travel signals the system to accelerate. If the driver repeatedly looks left and / or right (e.g., to check for pedestrians entering the road), the speed 202 is reduced. Accordingly, looking away from the direction of travel results in a reduction of the speed 202.

[0070] Furthermore, it can be checked before the action is carried out whether the driver has performed a check before looking in the direction of travel, so that it can be ruled out that acceleration occurs without the driver having had the opportunity to check for crossing traffic.24-3291

[0071] - 14 -

[0072] It may be necessary to use only head position, gaze direction, or a combination of both to achieve the most stable result. Gaze control can be applied to various settings, but is typically most relevant in dynamic situations. Even on country roads, looking in the direction of travel can ensure that the currently sensible maximum speed of 205 km / h is reached and / or maintained, while looking away for an extended period leads to a reduction in speed. In principle, the driver can consciously control their speed of 202 km / h through gaze control.

[0073] In one example, a vehicle approaches a traffic light at 100 km / h where a right turn is required. The light is green. The system recognizes the green light and therefore decides that the maneuver (turning at the traffic light) can proceed. The system may prompt the driver, via a beep or text message, to first perform a visual check and then signal acceleration by looking ahead. If this does not occur (for example, if the driver only looks to the left because a car is approaching there), the vehicle may come to a complete stop.

[0074] The driver can consciously control the vehicle's speed by looking ahead (just as they could with the vehicle's accelerator pedal). During the turning maneuver, the driver's gaze shifts to the right (the direction of travel has changed), and the gaze can follow this change, allowing the system to maintain the appropriate cornering speed for the vehicle. If the driver looks to the left while turning (for example, if there is a pedestrian), the speed is reduced. Once the driver realizes that the pedestrian does not intend to cross and looks back towards the direction of travel, the speed is increased again, and the maneuver is completed. 24-3291

[0075] - 15 -

[0076] Fig. 4 shows a flowchart of an exemplary (possibly computer-implemented) method 400 for setting the value 215 of the target speed 202 of a driving function for automated longitudinal and / or lateral control of a (motor) vehicle 100. The method 400 can be executed by a control device 101 of the vehicle 100. The set value 215 of the target speed 202 can be used by a speed controller as a setpoint to effect the automated longitudinal control of the vehicle 100.

[0077] Procedure 400 comprises determining 401 a target viewing direction 206 of the driver of vehicle 100 for monitoring the driving function. The target viewing direction 206 can be determined based on the anticipated planned driving trajectory 306 for the automated longitudinal and / or lateral guidance of vehicle 100 (e.g., based on a point on the driving trajectory 306).

[0078] Furthermore, the procedure 400 includes determining 402 the driver's actual viewing direction 216. The actual viewing direction 216 can be determined based on sensor data from one or more driver sensors 106, each configured to record sensor data relating to the driver.

[0079] The procedure 400 further comprises determining 403 the value 215 of the target speed 202 of the driving function as a function of the gaze direction deviation 201 of the actual gaze direction 216 from the target gaze direction 206 and as a function of a predefined functional relationship 200 between the gaze direction deviation 201 and the target speed 202. The functional relationship 200 can specify a value of the target speed 202 for a multitude of different values ​​of the gaze direction deviation 201. 24-3291

[0080] - 16 -

[0081] The measures described in this document enable comfortable and safe monitoring and control of a driving function for automated longitudinal and, if necessary, lateral guidance of a vehicle 100.

[0082] The present invention is not limited to the embodiments shown. In particular, it should be noted that the description and the figures are intended only to illustrate the principle of the proposed methods, devices, and systems by way of example.

Claims

24-3291 - 17 - Claims 1) Device (101) for setting the value (215) of the target speed (202) of a driving function for automated longitudinal and / or lateral control of a vehicle (100); wherein the device (101) is configured, - to determine a target viewing direction (206) of the driver of the vehicle (100) for monitoring the driving function; - to determine the driver's current viewing direction (216); and - to determine the value (215) of the target speed (202) of the driving function as a function of the gaze direction deviation (201) of the actual gaze direction (216) from the target gaze direction (206) and as a function of a predefined functional relationship (200) between the gaze direction deviation (201) and the target speed (202). 2) Device (101) according to claim 1, wherein the functional relationship (200) specifies a value (215) of the target speed (202) for a plurality of different values ​​of the viewing direction deviation (201). 3) Device (101) according to one of the preceding claims, wherein - the functional relationship (200) for a viewing direction deviation (201) from zero, where the actual viewing direction (216) corresponds to the desired viewing direction (206), has a maximum value (205); and - the functional relationship (200) is designed such that the value (315) of the target velocity (202) specified by the relationship (200) increases with increasing absolute value of the Gaze deviation (201) decreases. 24-3291 - 18 - 4) Device (101) according to claim 3, wherein the device (101) is configured to determine the maximum value (205), - based on a set speed for a vehicle speed controller (100) defined by the driver via a user interface (105) of the vehicle (100); and / or - based on sensor data from one or more environmental sensors (102) of the vehicle (100) relating to the vehicle's (100) environment; and / or - based on a prior driving trajectory (306) for the vehicle (100), which is used by the driving function for automated longitudinal and / or lateral guidance of the vehicle (100). 5) Device (101) according to one of the preceding claims, wherein - the viewing direction deviation (201) comprises an azimuth component with respect to an azimuth angle and an altitude component with respect to an altitude angle of the viewing direction; and - the functional relationship (200) for a multitude of different combinations of different values ​​of the azimuth component and of different values ​​of the altitude component gives a value (215) of the target velocity (202). 6) Device (101) according to one of the preceding claims, wherein the device (101) is configured to operate a speed controller depending on the determined value (215) of the target speed (202) in order to effect the automated longitudinal and / or lateral guidance of the vehicle (100). 7) Device (101) according to one of the preceding claims, wherein the device (101) is configured, 24-3291 - 19 - - to determine a future driving trajectory (306) for the operation of the driving function for automated longitudinal and / or lateral control of the vehicle (100); and - to determine the desired viewing direction (206) based on the preceding driving trajectory (306). 8) Device (101) according to one of the preceding claims, wherein the device (101) is configured to perform a sequence of successive time points, each time, - to determine a target viewing direction (206) and an actual viewing direction (216) for the respective time; and - based on the gaze direction deviation (201) for the respective time and using the functional relationship (200) to determine the value (215) of the target velocity (202) for the respective time. 9) Device (101) according to one of the preceding claims, wherein the device (101) is configured, - to determine a large number of measurements relating to the driver's gaze direction based on sensor data from at least one driver sensor (106); and - to determine the actual direction of view (216) of the driver based on the multitude of measured values, in particular on the basis of a frequency distribution (210) of the multitude of measured values. 10) Method (400) for determining the value (215) of the target speed (202) of a driving function for automated longitudinal and / or lateral control of a vehicle (100); wherein the method (400) comprises, - Determining (401) a target viewing direction (206) of the driver of the vehicle (100) for monitoring the driving function; - Determining (402) the driver's actual viewing direction (216); and 24-3291 - 20 - - Determining (403) the value (215) of the target speed (202) of the driving function as a function of the gaze direction deviation (201) of the actual gaze direction (216) from the target gaze direction (206) and as a function of a predefined functional relationship (200) between the gaze direction deviation (201) and the target speed (202).

Images