Method of operating a vehicle

Abstract

The present invention relates to a method for driving a vehicle (1) in an automated driving operation, in which a rear space of the vehicle (1) is continuously monitored, and if excessive approach of a following vehicle (2) to the vehicle (1) is detected, a warning (W) is output to the following vehicle (2), and if the following vehicle (2) continues to approach the vehicle (1) excessively after a predetermined time has elapsed, a handover request for a driving task is output to a vehicle user of the vehicle (1).

Description

Technical Field

[0001] The present invention relates to a driving method of a vehicle in an automatic driving operation.

Background Art

[0002] From German Patent Application Publication No. 102018204572, a vehicle control device and method for protecting a vehicle from a collision accident are known. This vehicle has an emergency brake function set so that the emergency brake of the vehicle is automatically activated. In this method, the control device is configured to determine that the probability of the emergency brake being automatically activated is high. Accordingly, at least one warning signal is generated to cause a following vehicle to maintain a sufficiently high safety distance to the vehicle.

[0003] Furthermore, German Patent Application Publication No. 10328755 describes a system for avoiding the distance from a following vehicle to a leading vehicle, particularly an automobile, from becoming too short. For this purpose, the leading vehicle is provided with a device for calculating the distance to the following vehicle and the relative speed to the following vehicle, and a minimum distance is calculated based on the calculated distance and relative speed. When the minimum distance is exceeded, measures are taken to prevent the distance from further decreasing in order to avoid a possible collision accident.

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a driving method of a vehicle in an automatic driving operation.

Means for Solving the Problems

[0005] According to the present invention, the above object is achieved by a method having the configuration shown in claim 1.

[0006] Advantageous embodiments of the present invention are the subject matter of the dependent claims.

[0007] In the driving method of a vehicle in an automatic driving operation according to the present invention, the vehicle rear space of the vehicle is continuously monitored. When an excessive approach of a following vehicle to the vehicle is detected, a warning is output to the following vehicle. When the following vehicle continues to approach the vehicle excessively even after a predetermined time has elapsed, a handover request regarding the driving task is output to the vehicle user of the vehicle.

[0008] By applying this method, the risk of an accident between the vehicle and the following vehicle can be reduced.

[0009] This method widens the distance to the vehicle and further enables the driver of the following vehicle to react to an unexpected braking operation of the vehicle due to, for example, a falsely detected obstacle, a so-called pseudo object or a ghost object. That is, this method provides additional protection against a collision with a following vehicle due to a false braking of a vehicle traveling in an automatic driving operation.

[0010] In this case, the distance between the two vehicles, especially the safety distance at which the following vehicle can react to the emergency braking of the vehicle, depends on the traveling speed. This is because the braking distance of the following vehicle becomes longer as the traveling speed increases.

[0011] When this method is used, the acceptability of the automatic driving operation of a vehicle, which may have insufficient aspects in some cases, can be enhanced.

[0012] In one embodiment of this method, when the driving task is not taken over after a predetermined additional time has elapsed, the current traveling speed of the vehicle is decreased by a predetermined value until the excessive approach between the following vehicle and the vehicle disappears. For example, when the vehicle is traveling without a driver, or when the vehicle user cannot perform the driving task manually due to an emergency or the like, the handover is not performed.

[0013] By reducing the driving speed of the vehicle, in particular, a signal will be given to the following vehicle to overtake the vehicle, or since the following vehicle is approaching the vehicle excessively, it will be suggested again that the following vehicle cannot react to a sudden braking of the vehicle. By reducing the speed, in particular, the risk of detecting a ghost target can also be further reduced.

[0014] In a further possible embodiment of the method, after a predetermined additional time has elapsed, the vehicle is controlled to move to the rightmost area within the lane in the case of right-hand traffic, or to the leftmost area within the lane in the case of left-hand traffic. At this time, the vehicle, in particular, reduces its driving speed and continues the automatic driving operation. That is, this process is executed when the handover request is not accepted and the vehicle reduces its driving speed by a predetermined value. In particular, as the vehicle travels towards the right or left lane demarcation line and reduces its driving speed so as to signal to the following vehicle to overtake the vehicle, the following vehicle can no longer approach the vehicle excessively. Thereby, even if the vehicle starts sudden braking due to a misdetected object, there is no longer a risk of collision for the vehicle with respect to the following vehicle.

[0015] In a further development form of the vehicle, a warning to the following vehicle can be output as a text message on a display device arranged at the rear of the vehicle. In particular, this text message includes content requesting to increase the distance of the following vehicle from the vehicle.

[0016] In an alternative or additional embodiment, this warning is output to the following vehicle by vehicle-to-vehicle communication. Thereby, the driver of the following vehicle can be directly warned. That is, it is possible to directly output a warning to the driver of the following vehicle. That is, this warning is directed directly at the driver of the following vehicle.

[0017] In a further embodiment of the present method, the time until the handover request is output to the vehicle is at least 30 seconds. That is, the output of the handover request is performed at the earliest 30 seconds after a warning is output to the following vehicle or after a warning is output inside the following vehicle. That is, the following vehicle is given at least 30 seconds of sufficient time to increase the distance from the autonomous vehicle in response to the warning of the vehicle.

[0018] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Mode for Carrying Out the Invention

[0020] In any of the figures, the same reference numerals are assigned to corresponding parts.

[0021] FIG. 1 shows a road section F having two opposing lanes F1 and F2. In the right lane F1, a vehicle 1 during autonomous driving operation and a following vehicle 2 of vehicle 1 are traveling. An oncoming vehicle 3 exists in the left lane F2.

[0022] The vehicle 1 is equipped with an assistance system for autonomous driving operation, and the vehicle 1, particularly the assistance system, executes the entire driving task so that the vehicle user can continue another activity during the autonomous driving operation.

[0023] The support system includes a surround sensor system having a number of detection units in and / or on the vehicle 1, at least one of which is designed as a sensor system 4 and includes a camera 4.1. The sensor system 4 in the form of the camera 4.1 is arranged in or on the vehicle 1 such that the detection area (details not shown) is directed forward of the vehicle 1, whereby the area of the road section F in front of the vehicle 1 is detected.

[0024] Obstacles around the vehicle 1 are detected using the detection signals of the surround sensor system and the camera 4.1. The control device of the surround sensor system determines the current degree of danger, particularly in relation to the detected obstacles. Depending on the determined degree of danger, if this degree of danger exceeds a particularly set threshold value, for example, the braking of the vehicle 1 is initiated to reduce the risk of collision between the vehicle 1 and the obstacle.

[0025] In some cases, a situation may occur where the sensor system 4 detects a pseudo-object 5, a so-called ghost object. Such a pseudo-object 5 is an object that does not actually exist but is detected by the sensor system 4 and thus becomes an obstacle. Due to the existence of such a pseudo-object 5, braking is erroneously initiated during the automatic driving operation of the vehicle 1. This means that the vehicle 1 starts braking, for example, an emergency brake, without an externally understandable reason.

[0026] For the pseudo-object 5, such initiated braking, a so-called false positive error, may lead to a rear-end collision accident between the vehicle 1 and the following vehicle 2. In particular, when the following vehicle does not maintain a sufficient distance from the vehicle 1, that is, when it approaches the vehicle 1 excessively, there is a risk of a rear-end collision accident.

[0027] If there is a sufficient distance between vehicle 1 and the following vehicle 2, such a rear-end collision accident can be avoided. In the case of vehicle 1 running in autonomous driving, since the control of the inter-vehicle distance is realized by the following vehicle 2, it is impossible for vehicle 1 to directly set a sufficient distance with respect to the following vehicle 2.

[0028] In order to significantly reduce the risk of such a rear-end collision accident caused by the insufficient distance between vehicle 1 and the following vehicle 2, the method described below is provided.

[0029] FIG. 2 shows a road section F having two opposing lanes F1 and F2. Vehicle 1 travels in the right lane F1 by an autonomous driving operation, and shows a state where a following vehicle 2 traveling behind vehicle 1 approaches vehicle 1 excessively from behind.

[0030] The surrounding sensor system includes at least one detection device, for example, a radar-based detection device, and monitors at least the rear space of the vehicle, that is, the area at the rear of vehicle 1 during the autonomous driving of vehicle 1.

[0031] When the following vehicle 2 is detected by the detection signal of this surrounding sensor system, if vehicle 1 starts false braking by the pseudo object 5, the distance a1 and the time interval t1 generally required for the following vehicle 2 to avoid a rear-end collision accident are calculated. This distance a1 and time interval t1 may particularly depend on the speed.

[0032] When the following vehicle 2 approaches vehicle 1 excessively and vehicle 1 starts false braking by the detected pseudo object 5, and the additional distance a2 and the additional time interval t2 become insufficient to the extent that a rear-end collision accident between the following vehicle 2 and vehicle 1 cannot be avoided, vehicle 1 gives a warning to the following vehicle 2.

[0033] In one embodiment, a warning W of the vehicle to the following vehicle 2 is output by displaying a text message. For this purpose, a display device 6 is arranged in the rear region of the vehicle 1. In particular, when the distance a1 and the time interval t1 are insufficient, the text message includes content that requests to widen the current distance a2 of the following vehicle 2 from the vehicle 1.

[0034] Alternatively or additionally, the warning W is transmitted to the following vehicle 2 by vehicle-to-vehicle communication and output within this vehicle. The driver of the following vehicle 2 thereby receives a direct warning from a support system, especially for active safety.

[0035] When the following vehicle 2 continues to approach the vehicle 1 excessively and the distance a1 and the time interval t1 become insufficient, after a predetermined time, for example, 30 seconds have elapsed, a takeover request is output to the vehicle 1 so that the vehicle user of the vehicle 1 manually executes the driving task of the vehicle 1.

[0036] For example, if the driving task cannot be taken over even after additional time has elapsed because there is no vehicle user in the vehicle 1 or because the vehicle user cannot execute the driving task in an emergency, the vehicle 1 reduces its current driving speed by a predetermined value. This serves as a signal for the following vehicle 2 to overtake the vehicle 1 considering at least one oncoming lane.

[0037] Furthermore, after this additional time has elapsed, the vehicle 1 can move closer to (move to) the area of the right lane demarcation line M within the lane F1, reduce its driving speed there, and continue the automatic driving operation. By moving closer to (moving to) the area of the right lane demarcation line M of the vehicle 1 and reducing the driving speed, the following vehicle 2 is required to perform an overtaking operation without endangering other road users.

[0038] When the following vehicle 2 overtakes the vehicle 1 or widens the distance a2 to at least the distance a1, the vehicle 1 returns its position to the center with respect to the right lane F1 and increases its current driving speed to the driving speed permitted for the automatic driving operation, particularly the driving speed applicable to that road section.

Prior Art Document

Patent Document

[0039]

Patent Document 1

Patent Document 2

Claims

1. In a method for driving a vehicle (1) in an automated driving operation, - the rear space of the vehicle (1) is continuously monitored, - when excessive approach of a following vehicle (2) to the vehicle (1) is detected such that the following vehicle (2) cannot avoid a collision with the vehicle (1) when the vehicle (1) suddenly brakes, a warning (W) is output to the following vehicle (2), - when the following vehicle (2) continues to approach the vehicle (1) excessively even after a predetermined time has elapsed, a handover request regarding the driving task is output to the vehicle user of the vehicle (1), - when the driving task is not handed over after a predetermined additional time has elapsed, the current driving speed of the vehicle (1) is reduced by a predetermined value and the automated driving operation continues until the excessive approach between the following vehicle (2) and the vehicle (1) disappears as the following vehicle (2) overtakes the vehicle (1), - after the predetermined additional time has elapsed, the vehicle (1) is controlled to move to a right-hand region within its lane (F1) in the case of right-hand traffic or to a left-hand region within its lane (F2) in the case of left-hand traffic A method for driving a vehicle, characterized by the above.

2. The warning (W) is output to the following vehicle (2) as a text message on a display device (6) arranged at the rear of the vehicle (1). A method for driving a vehicle according to Claim 1, characterized by the above.

3. The warning (W) is transmitted to the following vehicle (2) by vehicle-to-vehicle communication. A method for driving a vehicle according to Claim 1 or 2, characterized by the above.

4. The predetermined time until the handover request is output to the vehicle (1) is at least 30 seconds. A method for driving a vehicle according to Claim 1 or 2, characterized by the above.

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