METHOD FOR ADJUSTING THE DRIVING BEHAVIOR OF A VEHICLE

Description

[0001] The invention relates to a method for adapting the driving behavior of a vehicle driving in automated mode when an emergency vehicle in operation is detected in the vicinity of the vehicle, wherein the emergency vehicle is detected by means of its emitted acoustic special signal.

[0002] A method for controlling the distance of a vehicle is known from DE 10 2017 009 491 A1. In this method, traffic-relevant information from the vehicle's surroundings is recorded, and the vehicle's current speed is regulated and / or controlled depending on the detected distance to a vehicle ahead. The vehicle's speed is adjusted differently when the presence of at least one emergency vehicle is detected in the vicinity of the vehicle, compared to when no such presence is detected.

[0003] Furthermore, DE 10 2018 218 973 A1 describes a method for adapting an autonomous vehicle, an autonomous vehicle, a special-purpose vehicle, and a system. The method comprises the steps of determining a mission-specific characteristic of a special-purpose vehicle and / or wirelessly receiving mission-specific information transmitted by the special-purpose vehicle, and analyzing an environmental situation concerning the autonomous vehicle and the special-purpose vehicle based on the determined specific characteristic and / or the received mission-specific information.

[0004] German patent application DE 10 2013 2020 307 A1 discloses a method for assisting a driver in forming an emergency lane. This method provides that, during the formation of the emergency lane, an exceptional situation involving an emergency vehicle traveling in the opposite direction is detected, and the vehicle's steering is adjusted accordingly.

[0005] According to US 2019 / 283758 A1, a vehicle control device is provided that includes a detection unit for recognizing the vehicle's environment and a driving control unit for automatically controlling the vehicle's acceleration / deceleration and steering based on the environment detected by the detection unit. The detection unit recognizes a sound from a specific vehicle in the vicinity. If a characteristic of the sound detected by the detection unit meets a criterion, the driving control unit performs an evasive maneuver, causing the vehicle to move out of the way of the specific vehicle to avoid obstructing its path.

[0006] US patent 2020 / 257299 A1 discloses an autonomous vehicle that automatically reacts to an emergency vehicle. Cameras, sensors, and microphones of the autonomous vehicle capture and receive perception data. This data is used to detect lanes, create an object list, classify one or more objects, and determine the status of the classified objects. Upon detecting an emergency vehicle, such as a police car, the autonomous vehicle can plan a response.

[0007] US 2017 / 249839 A1 addresses a method for safe and automated navigation in the presence of emergency vehicles. A first vehicle can receive a message via communication hardware indicating the presence of the emergency vehicle. This message can originate from the emergency vehicle itself and / or from infrastructure such as a smart traffic light that can detect the presence of the emergency vehicle. The first vehicle can then determine the relative location of the emergency vehicle and automatically react accordingly by determining a safe trajectory and navigating until the emergency vehicle is out of range.

[0008] The invention is based on the objective of providing a method for operating a vehicle in the presence of a detected emergency vehicle in use in the vehicle's environment.

[0009] The problem is solved according to the invention by a method which has the features specified in claim 1.

[0010] Advantageous embodiments of the invention are the subject of the dependent claims.

[0011] A method for adapting the driving behavior of a vehicle operating in automated driving mode when an emergency vehicle is detected in the vicinity of the vehicle, wherein the emergency vehicle is detected by means of its emitted acoustic special signal, provides according to the invention that the vehicle is braked to a standstill upon detection of the emergency vehicle, wherein an evaluation of the acoustic special signal of the emergency vehicle is used to determine whether the emergency vehicle is also at a standstill, and depending on whether the emergency vehicle is at a standstill, the vehicle is moved forward from a momentary standstill position to a further standstill position.

[0012] In particular, the emergency vehicle is one belonging to the police, fire department or ambulance service.

[0013] By applying this procedure, it can largely be avoided that the automated vehicle is brought to a standstill by the emergency vehicle and remains in that state, especially while the emergency vehicle is sounding its siren. This can prevent a potential blockage of traffic flow caused by the stationary vehicle, as the siren sound received by the vehicle and emitted by the emergency vehicle is evaluated, allowing it to be determined whether the emergency vehicle is also stationary, has resumed its journey, or is about to restart.

[0014] The vehicle then determines again at the next stationary position whether the emergency vehicle in use is stationary, in order to be moved to a safe stationary position, for example in a parking lot or in a lay-by.

[0015] In one implementation, when the emergency vehicle is stationary, a reliability measure is determined for the reliability with which the stationary state of the vehicle is detected. This means that the detection of the stationary vehicle is comparatively good to poor, and the vehicle's driving behavior is adjusted accordingly, without the vehicle blocking other road users, especially other vehicles.

[0016] Another version of the procedure involves determining a distance between the vehicle and the emergency vehicle based on the calculated reliability score. The vehicle is then moved forward by this distance from its current stationary position to another stationary position. The vehicle thus approaches the emergency vehicle to again determine, based on the detected siren, whether the emergency vehicle is stationary or moving. Depending on the emergency vehicle's status, a decision is made as to whether the vehicle can be brought to a safe standstill, i.e., a position suitable for standing still, or whether automated driving can be resumed.

[0017] In a further training step, the vehicle's stationary position is checked again to determine whether it is indeed stationary. A reliability measure is then calculated for the accuracy with which the vehicle's stationary position was detected. This process is repeated until the vehicle reaches a stable stationary position. Thus, a multi-stage stationary detection system is used to signal whether the vehicle can proceed.

[0018] Furthermore, a possible advanced version of the procedure envisions the vehicle traveling from its current standstill position to reaching a safe standstill position at a speed below a predefined threshold. This threshold could be, for example, 10 km / h, allowing the vehicle to approach the emergency vehicle relatively slowly in order to perform another standstill detection. This allows the system to determine whether the vehicle needs to be moved to a safe standstill position or can resume its automated driving operation.

[0019] In another possible approach, it is determined whether the emergency vehicle is stationary if it is determined that the emergency vehicle is in front of the vehicle. For example, if it is determined that the emergency vehicle is in an oncoming lane, it is usually not necessary to bring the vehicle to a standstill, as the vehicle is not typically in the path of the emergency vehicle.

[0020] Furthermore, one implementation of the procedure stipulates that the vehicle's automated driving operation is resumed if the special acoustic signal emitted by the emergency vehicle is no longer detected by a sensor array on the vehicle. The emergency vehicle has then either resumed its driving operation and is proceeding to a different destination, particularly the deployment location, than the vehicle, or the deployment of the emergency vehicle has ended.

[0021] In another version, the vehicle is operated driverless in automated driving mode, so that there is no vehicle user in the vehicle who can take over the driving task with regard to the vehicle, or who can assess a given traffic situation with the emergency vehicle in order to then act appropriately.

[0022] Furthermore, one implementation of the method involves capturing the emergency vehicle's audible warning signal using a sensor array consisting of several microphones mounted on the vehicle. In particular, the detected audible warning signal allows the system to determine the direction and distance of the emergency vehicle relative to the other vehicle. This makes it relatively easy to ascertain whether the emergency vehicle is moving or stationary.

[0023] Exemplary embodiments of the invention are explained in more detail below with reference to a drawing.

[0024] This shows: Fig. 1 schematically shows a section of road with a vehicle and an emergency vehicle in front of it in operation.

[0025] The single figure shows a road section F with two lanes F1 and F2. A vehicle 1 is located in the right lane F1, and in front of it is an emergency vehicle 2, such as a police car, fire engine, or ambulance. The left lane F2 is empty and, for example, runs in the same direction as the right lane F1.

[0026] Vehicle 1 operates in automated, in particular highly automated, driving mode with an automation level of 4, so that there is no vehicle user in vehicle 1 who can intervene in a regulatory manner in certain traffic situations.

[0027] Typically, the automated vehicle 1 is brought to a standstill upon detecting an emergency vehicle 2 that is responding to an incident, for example, to avoid blocking the emergency vehicle 2. The fact that the emergency vehicle 2 is responding to an incident is primarily indicated by a special acoustic signal S, such as a siren.

[0028] In the event that the emergency vehicle 2 has reached its deployment location and the emission of the acoustic special signal S is not switched off, whereby this may be regulated country-specifically, the driverless automated vehicle 1 remains stationary, so that other road users may be blocked by the stationary vehicle 1.

[0029] The following describes a method for adapting the driving behavior of an automated vehicle 1, whereby a multi-stage standstill detection is carried out with respect to the emergency vehicle 2.

[0030] According to the in Figure 1 In the illustrated embodiment, the emergency vehicle 2 is positioned on the right-hand lane F1 of the road section F, with the acoustic special signal S continuing to be emitted.

[0031] The acoustic warning signal S is detected by means of a number of microphones 3 arranged on and / or in the vehicle 1 as a sensor arrangement. The microphones 3 are, for example, arranged on the roof 1.1 of the vehicle. By evaluating the acoustic warning signal S and / or based on signals detected by at least one optical detection unit of the vehicle 1, the direction and distance of the emergency vehicle 2 relative to the vehicle 1 can be determined.

[0032] The emergency vehicle 2, which is in operation, is recognized by vehicle 1 at least by the acoustic special signal S it emits, whereupon vehicle 1 is brought to a standstill.

[0033] When vehicle 1 is stationary, it determines, particularly based on the acoustic special signal S detected by microphones 3, whether emergency vehicle 2 is also stationary. This determination is only carried out if it is detected that emergency vehicle 2 is in front of vehicle 1, i.e., ahead of vehicle 1 in the direction of travel.

[0034] If it is determined that emergency vehicle 2 is stationary, a reliability measure is calculated for the reliability with which the stationary state of vehicle 1 was detected. Depending on the reliability measure, a distance is then determined, and vehicle 1 is subsequently moved forward by this specified distance towards emergency vehicle 2 to another stationary position.

[0035] In a first exemplary case, vehicle 1 is stationary because of the emergency vehicle 2 detected in front of it. No wind noise occurring during driving is recorded. If the acoustic special signal S is detected by the microphones 3 of vehicle 1 for a predetermined period of, for example, 10 seconds, with constant amplitude and direction, the reliability measure with regard to standstill detection is, for example, 1, where a reliability measure of 1 indicates that the standstill of the emergency vehicle 2 has been reliably detected.

[0036] With a reliability score of 1, vehicle 1 is moved at a maximum speed of 10 km / h (threshold value) by a specified distance, for example, 20 meters, towards emergency vehicle 2 from a momentary stationary position to another stationary position. At this further stationary position, vehicle 1 performs another stationary detection in relation to emergency vehicle 2, and a new reliability score is determined.

[0037] In a second exemplary case, vehicle 1 is stationary, and no wind noise caused by driving is detected by the microphones 3 of vehicle 1. If it is determined that the acoustic special signal S emitted by emergency vehicle 2 fluctuates in amplitude and direction over a predetermined period of, for example, 30 seconds, and integration shows that no movement of the acoustic special signal S, and thus of emergency vehicle 2, occurs (i.e., it remains constant on average), then the reliability measure with regard to the detection of the stationary state of emergency vehicle 2 is 2. Here, 2 represents the reliability measure that the detection of the stationary state of emergency vehicle 2 was averagely successful.

[0038] Such a case can occur in particular if the acoustic special signal S fluctuates, for example, due to background noise from a construction site and / or a truck and / or due to reflections of the acoustic special signal S off walls or buildings.

[0039] If reliability measure 2 is determined, vehicle 1 moves at a maximum speed of 10 km / h from its current stationary position to another stationary position located 10 m away from the current stationary position. At this further stationary position, another standstill detection is performed, and a reliability measure is then determined.

[0040] In a third exemplary case, the reliability measure determined with regard to the standstill detection of the emergency vehicle 2 is 3, which states that standstill detection is not possible, especially if the first case and the second case can be excluded.

[0041] With regard to the exemplary first and second cases, standstill detection continues until vehicle 1 reaches a suitable location, a so-called safe harbor, and can be brought to a safe standstill position. For example, a suitable location could be a parking space or a lay-by.

[0042] Once vehicle 1 has been moved to a safe stationary position at the appropriate location, it waits there until the special acoustic signal S emitted by the operational emergency vehicle 2 is no longer detected by the microphones 3 of vehicle 1. For example, emergency vehicle 2 has deactivated the emission of the special acoustic signal S or has started moving, so that emergency vehicle 2 is no longer stationary and is moving away from vehicle 1.

[0043] If the acoustic special signal S is no longer detected by vehicle 1, vehicle 1 resumes its automated driving operation in order to reach its destination.

Claims

1. Method for adapting the driving behavior of a vehicle (1) operating in an automated driving mode when an emergency vehicle (2) currently in use is detected in the vicinity of the vehicle (1), the emergency vehicle (2) being detected on the basis of its emitted special acoustic signal (S), the vehicle (1) becoming stationary upon detection of the emergency vehicle (2), characterized in that - by evaluating the special acoustic signal (S) of the emergency vehicle (2), it is determined whether the emergency vehicle (2) is also stationary, and - depending on whether the emergency vehicle (2) is stationary, the vehicle (1) is moved forward from a momentary stationary position to another stationary position.

2. Method according to claim 1, characterized in that when the emergency vehicle (2) is stationary, a reliability measure is determined for the reliability at which the stationary state of the emergency vehicle (2) was detected.

3. Method according to claim 2, characterized in that depending on the determined reliability measure, a distance between the vehicle (1) and the emergency vehicle (2) is established, and the vehicle (1) is moved forward by the established distance from its current stationary position to the other stationary position.

4. Method according to claim 3, characterized in that at the other stationary position of the vehicle (1), it is again determined whether the emergency vehicle (2) is stationary and a reliability measure for the reliability at which the stationary position of the emergency vehicle (2) was detected is determined, this process being repeated until the vehicle (1) has reached a safe stationary position.

5. Method according to claim 4, characterized in that the vehicle (1) travels from each stationary position until the safe stationary position is reached at a speed which is below a specified threshold.

6. Method according to any of the preceding claims, characterized in that it is only determined whether the emergency vehicle (2) is stationary if it is determined that the emergency vehicle (2) is in front of the vehicle (1).

7. Method according to any of the preceding claims, characterized in that the automated driving mode of the vehicle (1) is resumed when the special acoustic signal (S) emitted by means of the emergency vehicle (2) is no longer registered by a sensor arrangement of the vehicle (1).

8. Method according to any of the preceding claims, characterized in that the vehicle (1) is operated driverlessly in the automated driving mode.

9. Method according to claim 7 or 8, characterized in that the special acoustic signal (S) emitted by the emergency vehicle (2) is registered by means of a number of microphones (3) arranged on the vehicle (1) as a sensor arrangement.