INFORMATION, WARNING AND BRAKING REQUEST GENERATION FOR TURN ASSIST FUNCTIONALITY

Abstract

A method for warning a driver of a vehicle (1), in particular a truck, in turn maneuvers includes the following steps: generating (S1) an adaptive monitoring area (2) for the vehicle (1) based on at least a maximum lateral acceleration (4) of the vehicle (1) at a current longitudinal velocity (6) of the vehicle (1); identifying (S2) a vulnerable road user (VRU) (8) within the adaptive monitoring area (2); determining (S3, S4) a driver's intention to turn (40) the vehicle (1); determining S5) whether there is a collision risk between the vehicle (1) and the VRU (8); and outputting a warning signal (SW) based on the determined collision risk.

Claims

1. A method for warning a driver of a vehicle (1) in turn maneuvers, the method comprising the following steps: generating (S1) an adaptive monitoring area (2) for the vehicle (1) based on at least a maximum lateral acceleration (4) of the vehicle (1) at a current longitudinal velocity (6) of the vehicle (1); identifying (S2) a vulnerable road user (VRU) (8) within the adaptive monitoring area (2); determining (S3, S4) a driver's intention to turn (40) the vehicle (1); determining (S5) whether there is a collision risk between the vehicle (1) and the VRU (8); and outputting a warning signal (SW) based on the determined collision risk.

2. The method according to claim 1, wherein the adaptive monitoring area (2) includes at least a first quadrilateral (10) in front of the vehicle (1).

3. The method according to claim 2, wherein the adaptive monitoring area (2) includes at least a second quadrilateral (12) and a third quadrilateral (14) in front of the vehicle (1), wherein the first quadrilateral (10) and second quadrilateral (12) adjoin each other at a first common side (11), and the second quadrilateral (12) and the third quadrilateral (14) adjoin each other at a second common side (13).

4. The method according to claim 1, wherein the adaptive monitoring area (2) covers a predetermined time frame (t) for a movement of the vehicle (1), wherein the predetermined time frame (t) is in the range of 1.0 second to 3.0 seconds.

5. The method according to claim 4, 4, comprising the step of splitting the predetermined time frame (t) by a predetermined number of quadrilaterals (10, 12, 14) such that each quadrilateral (10, 12, 14) of the predetermined number of quadrilaterals covers a portion (t0, t1, t2) of the predetermined time frame (t).

6. The method according to claim 1, wherein generating (S1) the adaptive monitoring area (2) for the vehicle (1) is further based on a maximum road curve radius (R.sub.MAX) and minimum road curve radius (R.sub.MIN).

7. The method according to claim 1, wherein generating (S1) the adaptive monitoring area (2) for the vehicle (1) is further based on a maximum longitudinal acceleration (7) and/or change in acceleration (7) of the vehicle (1).

8. The method according to claim 1, wherein generating (S1) the adaptive monitoring area (2) for the vehicle (1) is further based on a maximum yaw rate (16) and/or change in yaw rate (16) of the vehicle (1).

9. The method according to claim 1, wherein the step of determining the driver's intention to turn the vehicle (1) includes: determining (S3) a probability that the driver intends to turn (40); and determining (S4) a probability that the driver is turning (44).

10. The method according to claim 9, wherein the probability that the driver intends to turn (40) is determined based on: a steering wheel angle (φ); a rate of change (dφ) of the steering wheel angle (φ); and a velocity (6) of the vehicle (1).

11. The method according to claim 10, comprising: calculating a predicted steering wheel angle (φ) for the adaptive monitoring area (2) using the steering wheel angle (φ), the rate of change (dφ) of the steering wheel angle (φ), and the velocity (6) of the vehicle (1).

12. The method according to claim 10, wherein, when the determined probability that the driver intends to turn (40) is 70% or more, it is assumed that it is the driver's intention to turn (40).

13. The method according to claim 9, wherein the probability that the driver is turning is determined based on: a steering wheel angle (φ); and a velocity (6) of the vehicle (1).

14. The method according to claim 13, wherein when the determined probability that the driver is turning (44) is 70% or more, it is assumed that the driver is turning (44).

15. The method according to claim 9, further comprising the step of outputting an information signal (SI) informing the driver (100) that a VRU (8) is in a vicinity (V) of the vehicle (1), upon determining that a VRU (8) is identified within the adaptive monitoring area (2); the driver does not intend to turn (40); and the driver is not turning (44).

16. The method according to claim 9, further comprising the step of outputting a warning signal (SW) warning the driver (100) that a VRU (8) is in a vicinity (V) of the vehicle (1) and that a collision may occur when the driver (100) starts turning upon determining that: a VRU (8) is identified within the adaptive monitoring area (2); the driver intends to turn (40); and the driver is not turning (44).

17. The method according to claim 9, further comprising the step of outputting a braking signal (SB) for braking the vehicle (1) upon determining that: a VRU (8) is identified within the adaptive monitoring area (2); the driver (100) intends to turn (40); and the driver (100) is turning (44).

18. A non-volatile computer memory storing a computer program (28) comprising instructions which, when the computer program (28) is executed by a processor (26), cause the processor (26) to carry out steps of a method comprising the following steps: generating (51) an adaptive monitoring area (2) for a vehicle (1) based on at least a maximum lateral acceleration (4) of the vehicle (1) at a current longitudinal velocity (6) of the vehicle (1); identifying (S2) a vulnerable road user (VRU) (8) within the adaptive monitoring area (2); determining (S3, S4) a driver's intention to turn (40) the vehicle (1); determining (S5) a collision risk is present between the vehicle (1) and the VRU (8); and outputting a warning signal (SW) based on the determined collision risk.

19. A turn assist system (20) for a vehicle (1) for warning a driver (100) of the vehicle (1) in turn maneuvers, comprising a control unit for a vehicle (1), the control unit (22) comprising: the non-volatile computer memory (24) according to claim 18; and a processor (26) configured to perform the computer program (28) stored on the non-volatile computer memory.

20. The turn assist system (20) of claim 19, wherein the control unit (22) comprises an interface (32) for communicating with an internal BUS-system (30) of the vehicle (1) to provide at least a braking signal (SB) to the BUS-system (30).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In the accompanying drawings,

[0036] FIG. 1 shows a schematic view of a vehicle and an adaptive monitoring area;

[0037] FIG. 2 shows a schematic flow diagram of the method for warning a driver of a vehicle;

[0038] FIG. 3 shows a further flow chart of a part of the method of warning the driver of the vehicle; and

[0039] FIG. 4 shows a schematic side view of a vehicle comprising a turn assist system.

DETAILED DESCRIPTION OF THE DRAWINGS

[0040] According to FIG. 1, a vehicle 1, in particular a truck 3, has an adaptive monitoring area 2 in front of it. The vehicle 1 has specific vehicle parameters, namely a maximum lateral acceleration 4, a current longitudinal velocity 6, and a maximum longitudinal acceleration 7. Moreover, the vehicle 1 comprises a yaw rate 16. These values are normally measured using sensors in a known manner.

[0041] The adaptive monitoring area 2 is generated based on these values and in FIG. 1 shown to be curved to the right-hand side of FIG. 1. This is due to the fact that the vehicle 1 is turning and running along a curve to the right. The curve is characterized by a maximum road curve radius R.sub.MAX and a minimum road curve radius R.sub.MIN. The minimum road curve radius R.sub.MIN may be defined by the curve of the street, or the pedestrians' way or the edge of the street. Maximum road curve radius R.sub.MAX in this instance may be defined by the maximum radius the vehicle 1 could take without running into the wrong direction, i.e. the lane of the other direction. The adaptive monitoring area 2 is generated also based on this minimum and maximum road curve radius R.sub.MIN, R.sub.MAX.

[0042] In the embodiments shown in FIG. 1, the adaptive monitoring area 2 comprises three quadrilaterals, namely a first quadrilateral 10, a second quadrilateral 12 and a third quadrilateral 14. The adaptive monitoring area 2 is generated to cover a predetermined time frame t, which in this embodiment may be 1.5 seconds. This predetermined time frame t is divided by the number of quadrilaterals, in this case three. Thus, this quadrilateral is associated for a time of 0.5 seconds. The first quadrilateral 10 is associated with the time frame t0 of 0.5 seconds, the second quadrilateral 12 is associated with the second time frame t1 of 0.5 seconds and the third quadrilateral 14 is associated with a third time frame t2 of 0.5 seconds. Together they cover the time of predetermined time frame t and the area, in which the vehicle 1 could be within this predetermined time frame t.

[0043] As can be seen, the quadrilaterals 10, 12, 14 are stacked in front of each other such that the first and second quadrilateral 10, 12 comprise a first common side 11 and the second and third quadrilateral comprise a second common side 13. In case the adaptive monitoring area 2 comprises further quadrilaterals as, e.g. a fourth, fifth, and so forth quadrilateral, again, they would be stacked in front of the third quadrilateral 14 and comprise a third common side with the third quadrilateral 14. I The invention is not restricted to three quadrilaterals and that a number of quadrilaterals could be chosen dependent on the application, or could also change during a single ride of the vehicle 1. E.g., the number of quadrilaterals could be based on the current velocity of the vehicle 1 and/or the load of the vehicle 1.

[0044] As it can also be seen in FIG. 1, the quadrilaterals 10, 12, 14 are wider to the front to account for the higher uncertainty for later time frames as, in particular, the latest time frame t2 in this embodiment.

[0045] In the embodiment shown in FIG. 1, a vulnerable road user (VRU) 8 is present in the current third quadrilateral 14. A vulnerable road user might be any vulnerable user as, e.g., a pedestrian, cyclist, motorcycle rider, car driver, or the like. The vulnerable road user 8 has the vicinity V to the vehicle 1. When such a vulnerable road user 8 is identified within the adaptive monitoring area 2, it is further determined, whether there is a collision risk between the vehicle 1 and the vulnerable road user 8. The definition of whether there is a collision risk may in one embodiment answered with “yes”, when the vulnerable road user 8 is within the adaptive monitoring area 2. Moreover, additional information such as a likely trajectory of the vehicle 1 could be taken into account to determine whether there is a collision risk. When, for example, the vulnerable road user 8 has a high velocity himself, e.g., with respect to FIG. 1 into the upper-left direction such that it is estimated when the vehicle 1 moves forward that the vulnerable road user 8 would not be within the adaptive monitoring area 2 anymore, and it could be determined that there is no collision risk.

[0046] Dependent on further actions of the driver 100 (see FIG. 4), one or more actions could be taken as, in particular, outputting a warning signal SW (see FIGS. 3, 4).

[0047] The general structure of the method according to the present application is shown in FIG. 2. The steps S1 to S5, shown in FIG. 2, might be carried out at least partially in a parallel manner, or one after each other. The method preferably is run again and again during the complete travel of the vehicle 1 as it is necessary to adapt the adaptive monitoring area 2 dependent on different driving situations.

[0048] In the first step S1, an adaptive monitoring area for the vehicle is generated. This is carried out as has been described with respect to FIG. 1, based on at least a maximum lateral acceleration 4 of the vehicle 1 at a current longitudinal velocity 6 of the vehicle 1. Moreover, the maximum longitudinal acceleration 7, the yaw rate 16, and change in this yaw rate 16, as well as minimum and maximum road curve radius R.sub.MIN, R.sub.MAX, can be taken into account.

[0049] For actually calculating the adaptive monitoring area 2, it is important to take into account all possible vehicle positions in future. To do this for the left edge of the adaptive monitoring area 2 (see FIG. 1), the maximum road curve radius R.sub.MAX and maximum feasible lateral acceleration 4 constraints are considered. Similarly, for right edge calculation, the calculation of the adaptive monitoring area 2 (see FIG. 1) minimum road curve radius R.sub.MIN and maximum feasible lateral acceleration 4 constraints are considered. Also for acceleration of the adaptive monitoring area 2, to detect the scenario where braking intervention via outputting the braking signal SB is required, only current dynamics of the vehicle 1 are taken into account, i.e. current velocity 6, yaw rate 16. No assumptions on dynamic and environmental constraints are considered for braking related adaptive monitoring area 2 acceleration.

[0050] When the adaptive monitoring area 2 has been generated, it is monitored all the time. In step S2, a vulnerable road user 8 is identified within the adaptive monitoring area 2 (see also FIG. 1). When the vulnerable road user 8 is identified (S2) it is determined whether it is the driver's intention to turn. This, according to the present embodiment, includes two steps S3, S4. In Step S3, the probability that the driver intends to turn is determined. In Step S4, the probability that the driver is turning is determined.

[0051] In one aspect of the invention, the step determining S3 a probability of the driver intends to turn 40 (see also FIG. 3) is based on a steering wheel angle φ, a rate of change dφ of the steering wheel angle φ and a velocity 6 of the vehicle 1. When, for example, the steering wheel angle φ is still rather small, but the rate of change dφ of the steering wheel angle φ is high, and the velocity 6 of the vehicle 1 is low, the probability that the driver intends to turn is rather high. On the other hand, when the steering wheel angle φ is small, a rate of change dφ of the steering wheel angle φ is low, and the velocity 6 of the vehicle is high, the probability of the driver intends to turn 40 is normally rather low and the small steering wheel angle φ is an indicator for a lengthy stretched curve.

[0052] In a similar manner, the step determining S4 a probability that the driver is turning, in one aspect of the invention is based on the steering wheel angle φ and the velocity 6 of the vehicle 1.

[0053] For both values, the probability of the driver intends to turn and he probability of the driver is turning, it is assumed that when this probability value is 70% or more that the driver actually intends to turn and that the driver is turning respectively.

[0054] In the last step S5, it is determined whether there is a collision risk between the vehicle 1 and the vulnerable road user 8, based on the adaptive monitoring area and the driver's intention to turn. Optionally, a warning signal SW may be outputted based on the above.

[0055] According to the present application, there are three levels of actions, which will be described now with respect to FIG. 3.

[0056] When there is no vulnerable road user 8 in the adaptive monitoring area 2, no signal is output. When a vulnerable road user 8 is identified within the adaptive monitoring area 2, in the next step, it is determined whether the driver 100 intends to turn. This is done with respect to FIG. 2, in steps S3 and S4. When it is determined that the driver 100 does not intend to turn, the warning signal SW is output. Usually, in this case, it is determined that there is no collision risk, even though the vulnerable road user 8 is identified within the adaptive monitoring area 2, the vehicle 1 will trespass along the vulnerable road user 8 without any further collision risk. The driver 100, however, is notified of the vulnerable road user 8 being in the adaptive monitoring area by the warning signal. Such a warning signal SW could include a visual or audio signal or also vibration signal of e.g. the steering wheel 50. A visual signal may include a respective sign in the windshield area or in a head-up display area or a side mirror When additionally, it is determined that the driver 100 is turning 44, not only a warning signal SW is output, but preferably a braking signal SB. The braking signal SB preferably is provided via a BUS-system 30 (see FIG. 4) to a central unit of a braking system of the vehicle 1, such that the vehicle 1 autonomously automatically brakes when it is determined that the driver is turning 44 within step S4.

[0057] FIG. 4 shows a basic principle of a cabin of the vehicle 1, having the turn assist system 20. The turn assist system 20 comprises a control unit 22, which may be provided within the vehicle. Control unit 22 comprises a memory 24 and a processor 26. On the memory 24, a computer program 28 comprising instructions, which, when carried out by the processor 26, cause the processor 26 to carry out steps of the disclosed method. The control unit 22 moreover comprises an interface 32 for a connection to the BUS-system 30.

[0058] The vehicle cabin comprises a steering wheel 50 as it is known in the art. In the cabin, moreover, there is a signal element 52 for outputting the warning signal SW and potential information signal SI. The steering wheel 50 is provided with a steering wheel sensor 54, which provides the steering angle φ and change in the steering wheel angle dφ to the control unit 22. Control unit 22 moreover is connected to a gas pedal 56, in particular to a gas pedal sensor 58. Gas pedal sensor 58 provides a gas signal S1 to the control unit 22.

[0059] When control unit 22 determined that a vulnerable road user 8 is within the adaptive monitoring area 2, and that a collision risk between the vehicle 1 and the vulnerable road user 8 is present, at least a warning signal SW is output via the signal element 52, and/or a braking signal SB is output via the BUS-system 30 to a central control of the braking system.