Overtaking assistant

Abstract

Overtaking assistant in an ego vehicle (1) with an electronic control unit (5) at least for receiving messages (M1; M2) from a vehicle-to-vehicle communication system of other vehicles (3; 4), wherein the messages (M1; M2) contain information ([XXX... 1]; [XXX... 0]) about the presence ([XXX... 1]) or absence ([XXX... 0]) of a vehicle (4) following the vehicle (3; 4) sending the message (M1; M2), wherein the control unit (5) evaluates these messages (M1; M2), and wherein the control unit (5) has filter means for identifying the first oncoming vehicle (3) and its message (M1) and activates warning means in the ego vehicle (1) to prevent an overtaking maneuver if the message (M1) from a first oncoming vehicle (3) contains the information ([XXX...1]) about the presence of a vehicle (4) following it, wherein the electronic control unit (5) of the ego vehicle (1) is also designed to send a message of a vehicle-to-vehicle communication system, wherein the message contains information about the presence or absence of a vehicle following the ego vehicle (1), characterized in that a message with the information about the presence or absence of a vehicle following the ego vehicle (1) is only sent or received if an overtaking situation can occur at least with a predetermined probability.

Description

[0001] The invention generally relates to an overtaking assistant. Between 2005 and 2008, BMW Research developed an overtaking assistant known as "Dynamic Pass Prediction" (DPP). DPP is a system that informs the driver of upcoming overtaking opportunities. To perform this function, the system uses the ACC (Adaptive Cruise Control) radar, knowledge of vehicle dynamics, the driver's driving style, and, in particular, digital map data. Whereas road layouts previously represented the most important features for route planning, other information now comes into play, such as details on road geometry, curves, inclines or declines, crests, road width, visibility, or even the currently recommended driving speed.

[0002] Navteq provides a prime example of this with its "Electronic Horizon." "Electronic Horizon" offers a preview of the upcoming route, including information that BMW's "Dynamic Pass Prediction" overtaking assistant also accesses. Using the Electronic Horizon's information about curves, merging roads, upcoming speed limits, or traffic lights, the BMW system calculates whether an overtaking maneuver could pose a hazard. If so, the driver is given a visual or audible warning to activate the turn signal.

[0003] For further technical background, please refer to DE 10 2011 084 878 A1 and DE 10 2004 019 337 A1.

[0004] Furthermore, WO 2006 / 037 360 A1 discloses a driver information system for informing the driver of a motor vehicle about the feasibility of overtaking maneuvers. This driver information system comprises means for determining additional vehicle variables relevant to overtaking maneuvers related to the driver's own vehicle and / or other vehicles. Furthermore, the driver information system has means for determining and outputting a measure of the feasibility of overtaking maneuvers.

[0005] In addition, US 2009 / 0 248 284 A1 describes a travel assistance system that supports the travel of a vehicle through vehicle-to-vehicle communication. A vehicle equipped with a communication system can also transmit information to another vehicle that is not equipped with a communication system. This information can, for example, describe the position and / or speed of the non-equipped vehicle.

[0006] Finally, DE 103 56 500 A1 discloses a vehicle communication device comprising a collecting device for collecting a plurality of pieces of information relating to the vehicle obtained therefrom, a selecting device for selecting pieces of information to be transmitted to the foreign moving object from the collected pieces of information relating to the vehicle, and a transmitting device which transmits only the selected pieces of information to the foreign moving object.

[0007] The object of the invention is to make a system of the type mentioned above even more reliable.

[0008] This object is achieved according to the invention by the subject matter of patent claim 1. The dependent patent claims are advantageous developments of the invention.

[0009] The overtaking assistant according to the invention in an ego vehicle has an electronic control unit at least for receiving messages from a vehicle-to-vehicle communication system of other vehicles. The messages contain information about the presence or absence of a vehicle following the vehicle sending the message, at least within a specific detection range. The control unit evaluates these messages as follows: The control unit has filter means for identifying the first oncoming vehicle and its message, and activates warning means in the ego vehicle to prevent overtaking if this message contains information about the presence of a following vehicle.

[0010] The term "vehicle-to-vehicle communication system" is used here in the broadest sense to refer to any system through which vehicles can communicate with each other; the term is therefore not limited to so-called "car-to-car communication systems" using the well-known "802.11p" wireless transmission technology. Such a vehicle-to-vehicle communication system could also be implemented via a mobile radio network, for example.

[0011] In addition, the electronic control unit of the ego vehicle is also configured to send a message via a vehicle-to-vehicle communication system, wherein the message contains information about the presence or absence of a vehicle following the ego vehicle. Thus, other vehicles can also be equipped with a corresponding overtaking assistant function.

[0012] In a preferred embodiment of the overtaking assistant according to the invention, the information about the presence of a vehicle following the vehicle sending the message additionally contains the distance to the following vehicle.

[0013] The term ego vehicle refers to the vehicle that contains the overtaking assistant according to the invention.

[0014] The invention is based on the following further considerations, findings and ideas: The BMW overtaking assistant DPP described above does not evaluate any information about oncoming vehicles.

[0015] The invention represents, in a sense, a cooperative, extended overtaking assistant in the sense of an "overtaking preventer" when safe overtaking is currently not possible. The invention is based on the well-known problem of a driver having to "feel their way around" to detect that oncoming traffic is approaching or that the road geometry does not allow safe overtaking.

[0016] In the case of overtaking assistants based on radio transmission technologies such as “802.11 p” in vehicle-to-vehicle communication systems (also called car-to-car or C2C communication), the relatively short radio range (200-600m) limits their usability to such an extent that a meaningful implementation is currently not possible.

[0017] The method described here enables a practical implementation of an overtaking assistant in the sense of an overtaking prevention assistant based on radio transmission technology with realistic prospects for a corresponding change in the standard (CAM, BSM, etc.) for vehicle-to-vehicle communication systems.

[0018] For example, with current standards, vehicles with vehicle-to-vehicle communication systems already transmit the position, direction, and speed of vehicles at a distance of approximately 200 to 600 m, depending on the degree of visual obscuration. However, especially when overtaking trucks, a restricted view for the driver of the ego vehicle is unfortunately usually accompanied by a reduction in radio transmission to the front, as this is also dampened / obscured by the truck. The ego vehicle therefore only receives the corresponding positions of oncoming vehicles relatively late, meaning that in many cases the overtaking prevention assistant would not give a red light because no data from oncoming vehicles is yet available. Accordingly, the driver often has to "pull out" himself to realize that overtaking is not yet possible.

[0019] This can be counteracted, for example, with the following exemplary embodiment according to the invention: The position information periodically transmitted by all vehicles equipped with car-to-car communication systems (e.g., "Here-I-Am" message), known from the so-called CAM (EU Cooperative Awareness Message) or BSM (US Basic Safety Message), is preferably extended by one bit. This bit is set to "0," for example, if a vehicle has no knowledge of a following vehicle traveling in the same direction within a range of x meters (e.g., 300 m) (either based on the CAM transmitted by the vehicle or through other on-board sensors, such as radar, PDC, camera, or lidar).

[0020] The bit is set to “1” accordingly if at least one following vehicle is detected within the defined range of x meters.

[0021] If, according to a preferred embodiment, the ego vehicle that wishes to overtake receives, for example, a CAM with a set bit ("1") from an oncoming vehicle 250 m away, it becomes known that another vehicle is following within the next 300 m. Accordingly, the overtaking assistant can wait for another oncoming vehicle before rechecking whether safe overtaking is possible.

[0022] In an advantageous further development, the distance to the next following vehicle can also be transmitted in the CAM. This would increase the quality of service, but depending on the resolution of the distance value, it would require additional bits to be transmitted.

[0023] Such a small and helpful change to the standard would have a real chance of being adopted into the ETSI (EU) and / or SAE (US) standards. By additionally integrating on-board sensors, the quality of service of the overtaking assistant can be improved.

[0024] According to the invention, a message containing information about the presence or absence of a vehicle following the ego vehicle is only sent or received if an overtaking situation can occur with at least a predetermined probability. This probability can be determined, for example, using data from a navigation system, which provides information about the road type, intersections, urban traffic, overtaking bans, etc. This allows the transmission bandwidth to be reduced in many cases.

[0025] Preferably, the vehicle-to-vehicle communication system is implemented via mobile radio, wherein the ego vehicle, when requesting to overtake, sends a requesting message that is receivable by at least the first oncoming vehicle, and wherein this vehicle only sends the message with information about the presence or absence of a vehicle following it in response to this request. In this case, the ego vehicle can, for example, transmit its position, direction, and speed, in particular only if overtaking is potentially possible at all. If another vehicle (at least the first oncoming vehicle) receives this request, it can calculate whether it is potentially opposed to this transmitted overtaking request and whether it can detect other following vehicles. If this is the case, this vehicle can activate a corresponding warning device, e.g.along with its own position, direction, track and speed.

[0026] The drawing shows a further embodiment of the invention. It shows an example of an overtaking situation in which the invention can be particularly advantageously applied.

[0027] The single figure shows an ego-vehicle 1 with an electronic control unit 5. The driver of ego-vehicle 1 is driving behind a truck 2 and wants to overtake it. A vehicle 3, not yet visible to the driver of ego-vehicle 1, is approaching in the opposite lane. This vehicle is followed by a vehicle 4 within a specific detection area B.

[0028] At least the ego vehicle 1 and the first oncoming vehicle 3 are each equipped with a vehicle-to-vehicle communication system. The first oncoming vehicle 3 sends a first message M1 via this system, which the ego vehicle 1 receives and evaluates.

[0029] It is essential to the invention that the message M1 is structured in such a way and can be evaluated by the control unit 5 of the ego vehicle 1 in such a way that the information can be determined in the control unit 5 as to whether a vehicle 4 following the first oncoming vehicle 3 is present at least in the defined minimum detection range B.

[0030] In a particularly advantageous manner, a bit is defined at a specific point (here, for example, at the end) of the digital message M1, which bit contains the information whether a following vehicle 4 is present [XXX...1] or not [XXX...0].

[0031] If this message extension is adopted into a standard for vehicle-to-vehicle communication systems, this information can be sent and received by any vehicle using this system. For example, vehicle 4 shown here can then also send a message M2 – here [XXX... 0] – stating that no other vehicle would follow this vehicle within its detection range.

[0032] Since not all vehicles will be equipped with a vehicle-to-vehicle communication system, at least for a longer transitional period, a vehicle - like vehicle 3 here (with vehicle-to-vehicle communication system) - can use other on-board sensors OBS to check whether it is being followed by vehicle 4 (if this is not equipped with a vehicle-to-vehicle communication system).

Claims

[1] Overtaking assistant in an ego vehicle (1) with an electronic control unit (5) at least for receiving messages (M1; M2) of a vehicle-to-vehicle communication system of other vehicles (3; 4), wherein the messages (M1; M2) contain information ([XXX... 1]; [XXX... 0]) about the presence ([XXX... 1]) or absence ([XXX... 0]) of a vehicle (4) following the vehicle (3; 4) sending the message (M1; M2), wherein the control unit (5) evaluates these messages (M1; M2), and wherein the control unit (5) has filter means for identifying the first oncoming vehicle (3) and its message (M1) and activates warning means in the ego vehicle (1) to prevent an overtaking maneuver if the message (M1) of a first oncoming vehicle (3) contains the information ([XXX...1]) about the presence of a vehicle (4) following it, wherein the electronic control unit (5) of the ego vehicle (1) is also designed to send a message of a vehicle-to-vehicle communication system, wherein the message contains information about the presence or non-presence of a vehicle following the ego vehicle (1). characterized by that a message containing information about the presence or absence of a vehicle following the ego vehicle (1) is only sent or received if an overtaking situation can occur with at least a predetermined probability. [2] Overtaking assistant according to claim 1, characterized by that the information about the presence of a vehicle following the vehicle sending the message also includes the distance to the following vehicle. [3] Overtaking assistant according to one of the preceding claims, characterized by that the vehicle-to-vehicle communication system is implemented via mobile radio, wherein the ego vehicle, when it wishes to overtake, sends out a requesting message which is receivable at least by the first oncoming vehicle, and wherein this vehicle sends out the message with the information about the presence or non-presence of a vehicle following it only in response to this request.

Images