Method for relaying early warning of forward traffic blind area risk through vehicle-to-vehicle communication

Abstract

The present application relates to a kind of methods for relaying early warning forward traffic blind area risk by car-car communication, comprising the following steps: S1, the type, position and motion trend information of real-time sensing forward traffic blind area target in system front car;S2, front car broadcast the information sensed together with the information of front car to rear main car in real time;S3, main car receives the sensing information broadcasted by front car in real time, and with the information collected by main car, information calibration is carried out in time and space;S4, main car adopts weighted sliding window average method to predict the motion trajectory of forward traffic blind area target;S5, main car judges whether there is conflict and risk with front car and forward traffic blind area target according to the predicted trajectory of forward traffic blind area target, based on collision time probability, and timely early warning.The present application can predict the motion trajectory of traffic target in blind area formed by front car shielding in advance, and real-time early warning possible traffic risk and conflict, enhance safety auxiliary driving effect.

Description

Technical Field

[0001] This invention relates to the field of automotive technology, and more specifically, to a method for providing early warning of forward traffic blind spot risks via vehicle-to-vehicle communication relay. Background Technology

[0002] Existing driver assistance systems, such as forward collision warning systems, can identify potential traffic risks or alert drivers to vehicles approaching too close when installed in a vehicle. However, these systems rely solely on the vehicle's sensors and do not consider the surrounding environment of the vehicle ahead. The system only issues a warning when the vehicle ahead brakes or takes actions that create a driving risk. This provides the driver with very little reaction time, and in extreme cases, a collision may not be avoided. If the vehicle ahead could broadcast critical information in real time, and the lead vehicle could receive and utilize this information promptly, it could predict the trajectory of traffic objects in blind spots created by the vehicle ahead, providing real-time warnings of potential risks and conflicts. Currently, vehicle-to-everything (V2X) systems enable real-time information exchange between vehicles and provide the BSM (Balance of Path) standard. Under this system, the lead vehicle's driver assistance systems can identify potential driving behaviors of the vehicle ahead and issue early warnings. However, driver assistance information is not yet integrated into these systems.

[0003] Current advanced driver assistance systems (ADAS) rely solely on the vehicle's own sensors, neglecting the environment of the vehicle ahead. The system only issues a warning when the vehicle ahead brakes or takes other actions that create a driving risk. This provides the driver with extremely limited reaction time, and in extreme situations, a collision may not be avoided. ADAS information is not yet incorporated into these systems. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for early warning of forward traffic blind spot risks through vehicle-to-vehicle communication relay. This method enables the host vehicle to collect the motion status information of the vehicle in front and the target in the forward traffic blind spot in real time, and predict the motion trajectory of the target in the forward traffic blind spot, so as to provide timely early warning of possible traffic risks and conflicts.

[0005] The technical solution adopted by this invention to solve its technical problem is: to construct a method for early warning of forward traffic blind spot risks through vehicle-to-vehicle communication relay, comprising the following steps:

[0006] S1. In the system, the vehicle in front uses its own sensors to perceive in real time the type, location and movement trend of targets in the blind spot of the traffic ahead;

[0007] S2. The vehicle in front broadcasts the sensed information, along with the information from the vehicle in front, to the vehicle behind in real time via the V2V method.

[0008] S3. The main vehicle receives the perception information broadcast by the preceding vehicle in real time via the V2V method, and performs time and space information calibration with the information collected by the main vehicle.

[0009] S4. The main vehicle displays the relative positional relationship between the main vehicle, the preceding vehicle, and the target in the blind spot ahead in the vehicle information fusion system, and uses a weighted sliding window averaging method to predict the trajectory of the target in the blind spot ahead.

[0010] S5. The main vehicle determines whether there is a conflict or risk with the vehicle in front and the target in the forward blind spot based on the predicted trajectory of the target in the forward traffic blind spot and the collision time probability, and issues a timely warning.

[0011] According to the above scheme, in step S1, the front vehicle's own sensor includes an on-board microwave radar, a lidar and an image sensing device. The front vehicle's own sensor is used to obtain the relative positional relationship of the forward or surrounding traffic targets relative to the vehicle.

[0012] The forward traffic blind spot target is a traffic blind spot formed when the main vehicle loses its forward view due to obstruction by the vehicle in front, and traffic targets such as vehicles or pedestrians existing in the traffic blind spot.

[0013] According to the above scheme, in step S2, the information that the vehicle in front needs to broadcast includes the vehicle speed. and heading angle Types and speeds of targets in forward traffic blind spots and direction of operation The lateral and longitudinal distances between the target in the forward blind spot and the vehicle in front. and .

[0014] According to the above scheme, in step S3, the information collected by the main vehicle includes the vehicle speed. and heading angle The lateral and longitudinal distances between the vehicle in front and the main vehicle and .

[0015] According to the above scheme, the time information calibration method is as follows:

[0016] Because the speed and direction of movement of targets in the forward traffic blind spot change over time, the detection time by the vehicle ahead... and the main vehicle receiving time The motion trend of the target in the forward traffic blind spot at the required time is calculated using a time interpolation calibration method.

[0017] The time interpolation calibration method assumes that, within a very short timeframe, the target in the forward traffic blind spot is treated as being in uniform linear motion, and the required time is calculated. The speed and direction of movement of the target in the forward traffic blind spot are:

[0018] (1)

[0019] in, , and The movement trend of the target in the traffic blind spot at any given time is ( , ), ( , ).

[0020] According to the above scheme, the spatial information calibration method is as follows:

[0021] The horizontal and vertical axes of the principal plane coordinate system are set as two directions parallel and perpendicular to the center dividing line of the road. Since the leading vehicle and the main vehicle have their own heading angles, the coordinate information is calibrated to a unified principal plane coordinate system by direct linear transformation.

[0022] With the front vehicle sensor as the origin, the coordinates of the target in the forward blind spot in the principal plane coordinate system are:

[0023] (2)

[0024] Similarly, with the main vehicle sensor as the origin, the coordinates of the target in the forward blind spot in the principal plane coordinate system are:

[0025] (3)

[0026] in, , .

[0027] According to the above scheme, in step S4, the main vehicle displays its relative positional relationship with the vehicle in front and the target in the forward blind spot in the vehicle information fusion system, that is, using coordinates ( ), ( ), ( The numbers () represent the horizontal and vertical distances in the principal plane coordinate system between the target in the forward blind spot and the main vehicle, the target in the forward blind spot and the vehicle in front, and the vehicle in front and the main vehicle. .

[0028] According to the above scheme, in step S4, the process by which the main vehicle relay system predicts the trajectory of the target in the forward traffic blind spot is as follows:

[0029] Since the lead vehicle and the preceding vehicle collect or receive information via V2V at regular intervals, and coordinates are a function of time, a weighted sliding window average method is used to predict the coordinates at the next moment. The formula is as follows:

[0030] (4)

[0031] in, , , These are the predicted lateral distances between the target in the forward traffic blind spot and the main vehicle, the target in the forward traffic blind spot and the vehicle in front, and the vehicle in front and the main vehicle at the next moment, respectively.

[0032] , , These are the predicted longitudinal distances between the target in the forward traffic blind spot and the main vehicle, the target in the forward traffic blind spot and the vehicle in front, and the vehicle in front and the main vehicle at the next moment, respectively.

[0033] The sliding window capacity is n, meaning that the actual values ​​from n fixed historical moments are used for prediction;

[0034] The weights are time-varying values; the closer the historical time is to the predicted time, the larger the corresponding weight value. An improved softmax function is used to represent these weight values.

[0035]

[0036] , , These are the actual lateral distances between the target in the forward traffic blind spot and the main vehicle, the target in the forward traffic blind spot and the vehicle in front, and the vehicle in front and the main vehicle at each historical moment.

[0037] , , These are the actual longitudinal distances between the target in the forward traffic blind spot and the main vehicle, the target in the forward traffic blind spot and the vehicle in front, and the vehicle in front and the main vehicle at each historical moment.

[0038] , , , , , To correct the parameters, the specific formula is as follows:

[0039] , , ;

[0040] The predicted coordinates of the target in the forward blind spot at the next moment can be obtained according to formula (4). The predicted distances between the vehicle in front and the main vehicle, and between the vehicle in front and the target in the forward blind spot at the next moment are calculated using the Euclidean distance formula. and ;

[0041] in, .

[0042] According to the above scheme, the process of determining whether there is a risk and conflict based on the collision time probability and issuing a timely warning in step S5 is as follows:

[0043] The main vehicle is based on the predicted distance at the next moment. and Real-time calculation of the predicted collision time between the main vehicle and the vehicle in front, and between the vehicle in front and the oncoming traffic target. and At the same time, a collision time threshold is set. ;

[0044] in, The collision time threshold is set at 1.5 times the driver's reaction time; if the collision time is predicted... If a collision time threshold is reached, the relay system will determine if there is a risk or conflict in the next moment and issue a warning signal.

[0045] Let event S be the main vehicle relay system issuing a warning signal, event A be a collision between the main vehicle and the vehicle in front, and event B be a collision between the vehicle in front and a target in the blind spot ahead. Using the concept of total probability, the probability of the main vehicle relay issuing a warning is:

[0046] (5)

[0047] in, , , Assuming a collision is possible, the relay system will issue a warning signal, i.e. ; , , It follows a 0-1 distribution, meaning that if the corresponding condition is met, its probability value is 1, otherwise it is 0.

[0048] The method for early warning of forward traffic blind spot risks via vehicle-to-vehicle communication relay of the present invention has the following beneficial effects:

[0049] This invention can sense traffic targets within blind spots created by obstructions from oncoming vehicles, predict their movement trends, and determine whether there is a conflict or risk with the lead vehicle. In the system, the leading vehicle uses its own sensors to perceive the type, location, and movement trend of targets in the blind spot in real time. The leading vehicle broadcasts the perceived information, along with other information from the leading vehicle, to surrounding vehicles in real time via a V2V method. The lead vehicle receives the perceived information broadcast by surrounding vehicles in real time via a V2V method and performs temporal and spatial information calibration with the information collected by the lead vehicle. The lead vehicle displays the relative positions of the lead vehicle, the leading vehicle, and the target in the blind spot within the vehicle information fusion system, and uses a weighted sliding window averaging method to predict the trajectory of the target in the blind spot. Based on the predicted trajectory of the target in the blind spot, the lead vehicle determines whether there is a conflict or risk with the leading vehicle and the target in the blind spot based on the collision time probability, and issues timely warnings. This allows the lead vehicle to provide early warnings of potential traffic risks, especially conflicts and risks arising from blind spots created by oncoming vehicles, enhancing the effectiveness of safety-assisted driving. Attached Figure Description

[0050] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0051] Figure 1 This is a flowchart of the method for early warning of forward traffic blind spot risks using vehicle-to-vehicle communication relay according to the present invention;

[0052] Figure 2 This is a schematic diagram of the method for warning of forward traffic blind spot risks via vehicle-to-vehicle communication relay in this invention. Detailed Implementation

[0053] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0054] like Figure 1 As shown, the method for early warning of forward traffic blind spot risks via vehicle-to-vehicle communication relay of the present invention includes the following steps:

[0055] S1. In the system, the vehicle in front uses its own sensors to perceive in real time the type, location and movement trend of targets in the blind spot of the traffic ahead;

[0056] The sensors of the vehicle itself include onboard microwave radar, lidar and image sensing equipment, which mainly acquire the relative positional relationship of forward or surrounding information with respect to the vehicle itself; the forward traffic blind spot target refers to the traffic blind spot formed when the main vehicle loses its forward view due to the obstruction of the vehicle in front, and traffic targets such as vehicles or pedestrians existing in the traffic blind spot.

[0057] S2. The vehicle in front broadcasts the sensed information, along with the information from the vehicle in front, to the vehicle behind in real time via the V2V method.

[0058] like Figure 2 The target of the forward traffic blind spot shown is a pedestrian crossing the road. The information that the vehicle in front needs to broadcast includes the speed of the vehicle in front. and heading angle Types and speeds of targets in forward traffic blind spots and direction of operation The lateral and longitudinal distances between the target in the forward blind spot and the vehicle in front. and .

[0059] S3. The main vehicle receives the perception information broadcast by the preceding vehicle in real time via the V2V method, and performs time and space information calibration with the information collected by the main vehicle.

[0060] The information collected by the main vehicle includes the vehicle speed. and heading angle The lateral and longitudinal distances between the vehicle in front and the main vehicle and .

[0061] The time information calibration method is as follows:

[0062] Because the speed and direction of movement of targets in the forward traffic blind spot change over time, the detection time by the vehicle ahead... and the main vehicle receiving time The motion trend of the target in the forward traffic blind spot at the required time is calculated using a time interpolation calibration method.

[0063] The time interpolation calibration method assumes that, within a very short timeframe, the target in the forward traffic blind spot can be treated as being in uniform linear motion, and the required time is calculated accordingly. The speed and direction of movement of the target in the forward traffic blind spot are

[0064] (1)

[0065] in, , and The movement trend of the target in the traffic blind spot at any given time is ( , ), ( , ).

[0066] The spatial information calibration method is as follows:

[0067] The horizontal and vertical axes of the principal plane coordinate system are set as two directions parallel and perpendicular to the center dividing line of the road. Since the leading vehicle and the main vehicle have their own heading angles, the coordinate information is calibrated to a unified principal plane coordinate system by direct linear transformation.

[0068] With the front vehicle sensor as the origin, the coordinates of the target in the forward blind spot in the principal plane coordinate system are:

[0069] (2)

[0070] Similarly, with the main vehicle sensor as the origin, the coordinates of the target in the forward blind spot in the principal plane coordinate system are:

[0071] (3)

[0072] in, , .

[0073] S4. The main vehicle displays the relative positional relationship between the main vehicle, the preceding vehicle, and the target in the blind spot ahead in the vehicle information fusion system, and uses a weighted sliding window averaging method to predict the trajectory of the target in the blind spot ahead.

[0074] The main vehicle displays its relative position to the vehicle in front and targets in the forward blind spot in the vehicle information fusion system, i.e., using coordinates ( ), ( ), ( The numbers () represent the horizontal and vertical distances in the principal plane coordinate system between the target in the forward blind spot and the main vehicle, the target in the forward blind spot and the vehicle in front, and the vehicle in front and the main vehicle. .

[0075] The process by which the main vehicle relay system predicts the trajectory of a target in the forward traffic blind spot is as follows:

[0076] Since the lead vehicle and the preceding vehicle collect or receive information via V2V at regular intervals, and coordinates are a function of time, a weighted sliding window average method is used to predict the coordinates at the next moment. The formula is as follows:

[0077] (4)

[0078] in, , , These are the predicted lateral distances between the target in the forward traffic blind spot and the main vehicle, the target in the forward traffic blind spot and the vehicle in front, and the vehicle in front and the main vehicle at the next moment, respectively.

[0079] , , These are the predicted longitudinal distances between the target in the forward traffic blind spot and the main vehicle, the target in the forward traffic blind spot and the vehicle in front, and the vehicle in front and the main vehicle at the next moment, respectively.

[0080] The sliding window capacity is n, meaning that the actual values ​​from n fixed historical moments are used for prediction;

[0081] The weights are time-varying values; the closer the historical time is to the predicted time, the larger the corresponding weight value. An improved softmax function is used to represent these weight values.

[0082]

[0083] , , These are the actual lateral distances between the target in the forward traffic blind spot and the main vehicle, the target in the forward traffic blind spot and the vehicle in front, and the vehicle in front and the main vehicle at each historical moment.

[0084] , , , , , To correct the parameters, the specific formula is as follows:

[0085] , , ;

[0086] The predicted coordinates of the target in the forward blind spot at the next moment can be obtained according to formula (4). The predicted distances between the vehicle in front and the main vehicle, and between the vehicle in front and the target in the forward blind spot at the next moment are calculated using the Euclidean distance formula. and ;

[0087] in, .

[0088] S5. The main vehicle determines whether there is a conflict or risk with the vehicle in front and the target in the forward blind spot based on the predicted trajectory of the target in the forward traffic blind spot and the collision time probability, and issues a timely warning.

[0089] The process of determining the existence of risks and conflicts based on collision time probability and issuing timely warnings is as follows:

[0090] The main vehicle is based on the predicted distance at the next moment. and Real-time calculation of the predicted collision time between the main vehicle and the vehicle in front, and between the vehicle in front and the oncoming traffic target. and At the same time, a collision time threshold is set. ;

[0091] in, The collision time threshold is set to 1.5 times the driver's reaction time; in this embodiment, it is set to 3 seconds. If the predicted collision time... If a collision time threshold is reached, the relay system will determine if there is a risk or conflict in the next moment and issue a warning signal.

[0092] Let event S be the main vehicle relay system issuing a warning signal, event A be a collision between the main vehicle and the vehicle in front, and event B be a collision between the vehicle in front and a target in the blind spot ahead. Using the concept of total probability, the probability of the main vehicle relay issuing a warning is:

[0093] (5)

[0094] in, , , Assuming a collision is possible, the relay system will issue a warning signal, i.e. ; , , It follows a 0-1 distribution, meaning that if the corresponding condition is met, its probability value is 1, otherwise it is 0.

[0095] Whether events A and B occur individually or simultaneously, the main vehicle relay system can be triggered to issue a warning signal, achieving the purpose of preventing traffic accidents caused by targets in the forward blind spot. A schematic diagram of the relay warning for targets in the forward blind spot is shown below. Figure 2 As shown.

[0096] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A method of relaying pre-warning forward traffic blind spot risks through car-car communication, characterized in that, Includes the following steps: S1. In the system, the vehicle in front uses its own sensors to perceive in real time the type, location and movement trend of targets in the blind spot of the traffic ahead; In step S1, the front vehicle's own sensor includes an onboard microwave radar, a lidar, and an image sensing device. The front vehicle's own sensor is used to obtain the relative positional relationship of forward or surrounding traffic targets relative to the vehicle. The forward traffic blind spot target is the traffic blind spot formed when the main vehicle loses its forward view due to the obstruction of the vehicle in front, and the traffic targets of vehicles or pedestrians existing in the traffic blind spot. S2. The vehicle in front broadcasts the sensed information, along with the information from the vehicle in front, to the vehicle behind in real time via the V2V method. S3. The main vehicle receives the perception information broadcast by the preceding vehicle in real time via the V2V method, and performs time and space information calibration with the information collected by the main vehicle. S4. The main vehicle displays the relative positional relationship between the main vehicle, the preceding vehicle, and the target in the blind spot ahead in the vehicle information fusion system, and uses a weighted sliding window averaging method to predict the trajectory of the target in the blind spot ahead. S5. The main vehicle determines whether there is a conflict or risk with the vehicle in front and the target in the forward blind spot based on the predicted trajectory of the target in the forward traffic blind spot and the collision time probability, and issues a timely warning. In the step S4, the host vehicle displays the relative position relationship between the preceding vehicle and the forward traffic blind area target in the vehicle information fusion system, i.e. the horizontal and vertical distances between the forward traffic blind area target and the host vehicle, between the forward traffic blind area target and the preceding vehicle, and between the preceding vehicle and the host vehicle are respectively represented by coordinates (x1, y1), (x2, y2) and (x3, y3). ;​​​ In step S4, the process by which the main vehicle relay system predicts the trajectory of a target in the forward traffic blind spot is as follows: Since the lead vehicle and the preceding vehicle collect or receive information via V2V at regular intervals, and coordinates are a function of time, a weighted sliding window average method is used to predict the coordinates at the next moment. The formula is as follows: （4） wherein, , , are the predicted lateral distance values of the next time instance for the forward blind-zone target and the host vehicle, the forward blind-zone target and the preceding vehicle, and the preceding vehicle and the host vehicle, respectively. , , are the longitudinal distance prediction values of the next moment of the forward traffic blind area target and the host vehicle, the forward traffic blind area target and the preceding vehicle, and the preceding vehicle and the host vehicle, respectively. The sliding window capacity is n, meaning that the actual values ​​from n fixed historical moments are used for prediction; The weight value is a function of time, the closer the historical time and the predicted time, the greater the corresponding weight value. The improved softmax function is used to represent the weight value, that is, , , are respectively actual values of the lateral distance between the forward traffic blind area target and the host vehicle, the forward traffic blind area target and the preceding vehicle, and the preceding vehicle and the host vehicle at each historical moment. , , are respectively actual values of the longitudinal distance between the forward traffic blind area target and the host vehicle, the forward traffic blind area target and the preceding vehicle, and the preceding vehicle and the host vehicle at each historical moment. , , , , , is a correction parameter, and the specific formula is: ， ， ； According to formula (4), the predicted coordinates of the forward traffic blind area target at the next moment can be obtained, and the Euclidean distance formula is used to calculate the predicted distances between the front vehicle and the host vehicle and between the front vehicle and the forward traffic blind area target at the next moment and ; wherein ; In step S5, the process of determining whether there is a risk or conflict based on the collision time probability and issuing a timely warning is as follows: The host vehicle according to the predicted distance at the next time And Real-time calculation of the predicted collision time of the host vehicle and the preceding vehicle, and the preceding vehicle and the forward traffic target at the next time And Set the collision time threshold value ; wherein, , the collision time threshold is set to 1.5 times the driver reaction time; if the predicted collision time collision time threshold, the relay system will determine that there is a risk and conflict at the next moment, and issue a warning signal; Let event S be the main vehicle relay system issuing a warning signal, event A be a collision between the main vehicle and the vehicle in front, and event B be a collision between the vehicle in front and a target in the blind spot ahead. Using the concept of total probability, the probability of the main vehicle relay issuing a warning is: （5） wherein , , , it is assumed that the relay system will always send a warning signal in case of a possible collision accident, i.e. ; , , obeys a 0-1 distribution, i.e. fulfils the corresponding condition with probability value 1, otherwise 0.

2. The method for relaying pre-warning forward traffic blind area risks through car-car communication of claim 1, wherein, The information broadcasted by the preceding vehicle in step S2 includes the speed of the preceding vehicle and the heading angle , the type, running speed and running direction of the forward traffic blind area target , the lateral and longitudinal distances between the forward traffic blind area target and the preceding vehicle and .

3. The method for relaying pre-warning forward traffic blind area risks through car-car communication of claim 1, wherein, The information collected by the host vehicle in step S3 includes the speed of the host vehicle and the heading angle , the lateral and longitudinal distances between the host vehicle and the preceding vehicle and .

4. The method for relaying pre-warning forward traffic blind area risks through car-car communication according to claim 3, characterized in that, The time information calibration method is as follows: Due to the motion speed and direction of the forward traffic blind area target changing with time, the detection time of the front vehicle and the receiving time of the host vehicle , the motion trend of the forward traffic blind area target at the required time is calculated by using a time interpolation calibration method; The time interpolation calibration method considers that the forward traffic blind area target is regarded as a uniform straight line motion state for processing in a very short time, and the motion speed and direction of the forward traffic blind area target at the required time calculated are: ​ （1） wherein , and the motion trend of the forward traffic blind area target at the moment (t) is , ), , .

5. The method for relaying pre-warning forward traffic blind area risks through car-car communication of claim 4, wherein, The spatial information calibration method is as follows: The horizontal and vertical axes of the principal plane coordinate system are set as two directions parallel and perpendicular to the center dividing line of the road. Since the leading vehicle and the main vehicle have their own heading angles, the coordinate information is calibrated to a unified principal plane coordinate system using a direct linear transformation. With the front vehicle sensor as the origin, the coordinates of the target in the forward blind spot in the principal plane coordinate system are: （2） Similarly, with the main vehicle sensor as the origin, the coordinates of the target in the forward blind spot in the principal plane coordinate system are: （3） wherein , .

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