CN111816003A

CN111816003A - Vehicle early warning method and device and computer equipment

Info

Publication number: CN111816003A
Application number: CN201910296096.3A
Authority: CN
Inventors: 蔡之骏; 杨波; 张志德; 张莹; 冯其高
Original assignee: Guangzhou Automobile Group Co Ltd
Current assignee: Guangzhou Automobile Group Co Ltd
Priority date: 2019-04-12
Filing date: 2019-04-12
Publication date: 2020-10-23
Anticipated expiration: 2039-04-12
Also published as: CN111816003B

Abstract

The application relates to a vehicle early warning method, a vehicle early warning device and computer equipment. The method comprises the following steps: acquiring vehicle information of a main vehicle and vehicle information of a vehicle to be early-warned, and determining whether a closest distance point closest to the main vehicle exists on a motion trail of the vehicle to be early-warned or not by adopting a kinematic bicycle model according to the vehicle information of the main vehicle and the vehicle information of the vehicle to be early-warned; if the vehicle to be pre-warned is in collision with the main vehicle, determining the collision time of the vehicle to be pre-warned and the main vehicle according to the vehicle motion parameters; and carrying out safety early warning on the vehicle to be early warned according to the collision time and the closest point of the distance. The vehicle information is used for representing the driving state and the physical attribute information of the vehicle. By adopting the method, the early warning accuracy of the vehicle can be improved.

Description

Vehicle early warning method and device and computer equipment

Technical Field

The application relates to the technical field of automatic driving, in particular to a vehicle early warning screening method and device and computer equipment.

Background

With the development of science and technology, vehicle-to-outside information exchange (V2X for short) system technology is widely applied to automatic driving, wherein the most critical application includes collision warning for vehicles.

In general, a vehicle warning method is to monitor a road condition through various sensors, such as a camera or a radar, so as to implement vehicle warning. However, in the V2X system, since there is no sensor such as a camera or a radar, it is possible to obtain the curvature of the road from the driving angle of the vehicle by using the curvature of the road obtained from the high-precision map, and to perform the vehicle warning based on the curvature of the current road.

However, since the curvature of the road acquired by using the high-precision map deviates from the actual situation, and the curvature of the actual route on which the vehicle travels during traveling is not necessarily the same as the curvature of the road, the acquired curvature of the road is not accurate, and thus a large error is easily generated, resulting in low accuracy of the warning.

Disclosure of Invention

In view of the foregoing, it is necessary to provide a vehicle warning method, device and computer device capable of improving the warning accuracy.

In a first aspect, an embodiment of the present application provides a vehicle early warning method, where the method includes:

acquiring vehicle information of a main vehicle and vehicle information of a vehicle to be early-warned; the vehicle information is used for representing the driving state and physical attribute information of the vehicle;

determining whether a closest distance point closest to the main vehicle exists on the motion trail of the vehicle to be early warned or not by adopting a kinematic bicycle model according to the vehicle information of the main vehicle and the vehicle information of the vehicle to be early warned;

if the vehicle to be pre-warned is in collision with the main vehicle, determining the collision time of the vehicle to be pre-warned and the main vehicle according to the vehicle motion parameters;

and carrying out safety early warning on the vehicle to be early warned according to the collision time and the closest point of the distance.

In a second aspect, an embodiment of the present application provides a vehicle warning device, where the device includes:

the acquisition module is used for acquiring the vehicle information of the main vehicle and the vehicle information of the vehicle to be early-warned; the vehicle information is used for representing the driving state and physical attribute information of the vehicle;

the processing module is used for determining whether a closest distance point closest to the main vehicle exists on the motion trail of the vehicle to be early warned by adopting a kinematic bicycle model according to the vehicle information of the main vehicle and the vehicle information of the vehicle to be early warned; if the vehicle to be pre-warned is in collision with the main vehicle, determining the collision time of the vehicle to be pre-warned and the main vehicle according to the vehicle motion parameters; and carrying out safety early warning on the vehicle to be early warned according to the collision time and the closest point of the distance.

In a third aspect, an embodiment of the present application provides a computer device, including a memory and a processor, where the memory stores a computer program, and the processor implements the following steps when executing the computer program:

According to the vehicle early warning method, the vehicle early warning device and the computer equipment, the vehicle information can represent the running state and the physical attribute information of the vehicle, so that the vehicle early warning device can determine the running characteristics of the two vehicles according to the vehicle information of the main vehicle and the vehicle information of the vehicle to be early warned, and the kinematic bicycle model is introduced into the early warning process, so that the accurate vehicle motion characteristic can be obtained, and then the accurate motion characteristic is added into the early warning process, so that the accuracy of vehicle track prediction is greatly improved. And then the vehicle early warning device can more accurately judge whether the movement track of the vehicle to be early warned has the closest distance point with the nearest distance to the main vehicle according to the movement track of the vehicle, so that the vehicle early warning device can accurately determine whether the vehicle to be early warned has the possibility of collision with the main vehicle, and based on the result, under the condition that the closest distance point exists on the movement track of the vehicle to be early warned, more accurate collision time is determined according to the accurate movement characteristic of the vehicle, and then the vehicle to be early warned is accurately early warned according to the collision time and the closest distance point. By adopting the method, the vehicle early warning device adopts the kinematic bicycle model to determine the running characteristics of the two vehicles, thereby greatly improving the accuracy of vehicle track prediction, further greatly improving the accuracy of early warning and ensuring that the vehicles run more safely.

Drawings

FIG. 1a is a diagram of an application scenario of a vehicle screening method and a vehicle warning method to be warned in one embodiment;

FIG. 1b is a diagram of the internal structure of a computer device in one embodiment;

FIG. 2 is a schematic flow chart of a vehicle screening method to be warned according to an embodiment;

FIG. 2a is a schematic view of a relationship of parameters involved in a bicycle equation of motion according to an embodiment;

FIG. 2b is a schematic diagram illustrating a relationship between relative motions of a host vehicle and a vehicle to be warned at a first moment according to an embodiment;

FIG. 2c is a schematic diagram illustrating a relative motion relationship between the host vehicle and the vehicle to be warned at time n according to an embodiment;

fig. 3 is a schematic flow chart of a vehicle screening method to be warned according to another embodiment;

FIG. 4 is a schematic flow chart illustrating a vehicle screening method to be pre-warned according to another embodiment;

FIG. 5 is a schematic flow chart illustrating a vehicle screening method to be pre-warned according to another embodiment;

FIG. 6 is a schematic flow chart illustrating a vehicle screening method to be pre-warned according to another embodiment;

FIG. 6a is a schematic diagram illustrating the sub-region division provided in one embodiment;

FIG. 6b is a schematic illustration of a positional relationship between a host vehicle and a remote vehicle according to yet another embodiment;

FIG. 6c is a schematic view of the main vehicle and the remote vehicle in a positional relationship according to another embodiment;

FIG. 7 is a schematic flow chart diagram of a vehicle warning method according to an embodiment;

FIG. 8 is a schematic flow chart diagram illustrating a vehicle warning method according to another embodiment;

FIG. 9 is a schematic flow chart illustrating a vehicle warning method according to yet another embodiment;

FIG. 10 is a schematic flow chart diagram illustrating a vehicle warning method according to yet another embodiment;

fig. 11 is a schematic structural diagram of a vehicle warning device according to an embodiment.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

The vehicle screening method and the vehicle early warning method to be early warned provided by the embodiment of the application can be applied to the system shown in fig. 1a, the system comprises a vehicle and a drive test unit, and the system can be a V2X system, and the V2X system (comprising V2V, vehicle to vehicle communication and V2I, vehicle to roadside unit communication) periodically broadcasts the vehicle information of the vehicle and the motion characteristics of the vehicle. Optionally, vehicle information broadcast by other vehicles may also be received.

The above method may be applied to a computer device as shown in fig. 1 b. The computer device comprises a processor, a memory, a network interface, a database, a display screen and an input device which are connected through a system bus. Wherein the processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device comprises a nonvolatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of an operating system and computer programs in the non-volatile storage medium. The database of the computer device is used for storing the screening rules and/or conditions in the following embodiments, and the specific description of the screening rules and/or conditions refers to the specific description in the following embodiments. The network interface of the computer device may be used to communicate with other devices outside over a network connection. Optionally, the computer device may be a server, a desktop, a personal digital assistant, other terminal devices such as a tablet computer, a mobile phone, and the like, or a cloud or a remote server, and the specific form of the computer device is not limited in the embodiment of the present application. The display screen of the computer equipment can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer equipment can be a touch layer covered on the display screen, a key, a track ball or a touch pad arranged on the shell of the computer equipment, an external keyboard, a touch pad or a mouse and the like. Of course, the input device and the display screen may not belong to a part of the computer device, and may be external devices of the computer device.

Those skilled in the art will appreciate that the architecture shown in fig. 1 is merely a block diagram of some of the structures associated with the disclosed aspects and is not intended to limit the computing devices to which the disclosed aspects apply, as particular computing devices may include more or less components than those shown, or may combine certain components, or have a different arrangement of components.

The following describes the technical solutions of the present application and how to solve the above technical problems with specific examples. The following several specific embodiments may be combined with each other, and details of the same or similar concepts or processes may not be repeated in some embodiments. Embodiments of the present application will be described below with reference to the accompanying drawings.

It should be noted that the execution subject of the following method embodiments may be a vehicle screening device to be warned and/or a vehicle warning device, and the device may be implemented as part or all of the computer device by software, hardware, or a combination of software and hardware. The following method embodiments are described by taking the execution subject as the computer device as an example.

In the embodiment of the application, through screening surrounding vehicles, other vehicles without risks are removed to obtain the vehicle to be pre-warned, so that the number of the vehicles needing to be pre-warned and calculated is reduced, and the calculated amount of vehicle pre-warning is reduced. By introducing the kinematic bicycle model into the early warning method, the motion parameters of the vehicle can be introduced, so that accurate early warning is realized. In order to make the early warning process more effective, the remote vehicles may be screened first, and a detailed description of a screening method for the vehicle to be early warned is provided below.

Fig. 2 is a schematic flow chart of a vehicle screening method to be warned according to an embodiment. The embodiment relates to a process of screening vehicles by computer equipment according to vehicle information and adopting a preset screening rule. As shown in fig. 2, the method includes:

s101, acquiring vehicle information of a main vehicle and vehicle information of a plurality of remote vehicles; the vehicle information is used for representing the driving state and the physical attribute information of the vehicle.

Specifically, a vehicle provided to a computer device, which can periodically broadcast vehicle information of the host vehicle through the V2X system while receiving vehicle information of distant vehicles existing in the periphery, is taken as the host vehicle. Optionally, the computer devices may also interact with roadside units and remote vehicles via the V2X system to obtain vehicle information from each other. Alternatively, the vehicle information may be transmitted through a network, such as a 3G network, a 4G network, or a 5G network. It should be noted that the vehicle information is used to represent the driving state of the vehicle, such as speed and acceleration, and may also represent the physical attribute information of the vehicle, such as position, size and contour.

S102, acquiring vehicle operation parameters according to the vehicle information of the main vehicle and the vehicle information of the multiple remote vehicles; the vehicle operation parameters are used for describing the motion trail states of the main vehicle and the remote vehicle.

Specifically, the computer device performs mathematical and physical calculations based on the vehicle information of the host vehicle and the vehicle information of the remote vehicle, so that vehicle operation parameters can be obtained. The vehicle operation parameters can describe the motion trail state of the main vehicle, the motion trail state of the distant vehicle and the relative motion trail state of the two vehicles. For example, the computer device can derive the velocity of the far vehicle relative to the host vehicle from the velocity of the host vehicle and the velocity of the far vehicle.

S103, screening the vehicles to be early-warned from the plurality of remote vehicles by adopting a preset screening rule according to the vehicle operation parameters; the screening rules include correlations between the vehicle operating parameters.

Specifically, the computer device can screen out vehicles without collision risks from a plurality of remote vehicles according to the vehicle operation parameters and preset screening rules, and leave the vehicles with collision risks as the vehicles to be pre-warned. The screening rule may include a relative relationship between vehicle operating parameters, a relationship between vehicle operating parameters and a preset parameter threshold, and optionally, a special rule set according to a national standard requirement, an enterprise requirement, or a road condition of a common region.

In this embodiment, because the vehicle operation parameters can describe the motion track states of the main vehicle and the remote vehicles, the vehicle information is used to represent the driving state and the physical attribute information of the vehicle, and the screening rule includes the correlation between the vehicle operation parameters, the computer device can determine the vehicle operation parameters according to the vehicle information of the main vehicle and the vehicle information of the remote vehicles, and determine the correlation between the vehicle operation parameters by using the preset screening rule, so as to screen out the vehicle to be pre-warned with a collision risk from the plurality of remote vehicles for pre-warning. According to the method, the screening rule comprising the correlation among the vehicle operation parameters is adopted to judge the correlation among the vehicle operation parameters, so that the vehicle operation track can be estimated more accurately, the collision risk of a remote vehicle can be estimated more accurately, the determined vehicle to be pre-warned is more accurate, the problem of low accuracy caused by screening the vehicle according to a single basis in the traditional technology can be solved, the accuracy of screening the vehicle can be greatly improved, the invalid pre-warning is greatly reduced, the effective pre-warning is improved, the pre-warning of the vehicle is more targeted, and the vehicle pre-warning in the traffic process is more accurate and more effective.

In one embodiment, the filtering rule includes at least one of the following rules: a first screening rule: the distance between the mass centers of the two vehicles is less than or equal to the preset primary screening radius; the second screening rule is as follows: an included angle between a centroid connecting line vector of the two vehicles and a relative motion track vector of the two vehicles is an acute angle, and the centroid distance of the two vehicles is smaller than or equal to a preset early warning radius; the third filtering rule includes: the running speed of the main vehicle is greater than a preset safe speed per hour threshold value, the relative running speed of the far vehicle relative to the main vehicle is greater than the safe speed per hour threshold value, and the centroid distance of the two vehicles is greater than the early warning radius.

Specifically, the filtering rule may include any one of the first filtering rule, the second filtering rule, and the third filtering rule, may also include a combination of any two of the first filtering rule, the second filtering rule, and the third filtering rule, which is not limited in this embodiment. The first screening rule may include that the distance between the centers of mass of the two vehicles is greater than a preset preliminary screening radius, which may be preset, for example, it may be set according to road conditions. The first filtering rule can be formulated

Or a variation of this formula, wherein

The centroid connecting line vector of the two vehicles is shown, and A and B respectively represent the centroid coordinates of the two vehicles; r is a preset primary screening radius which can be set according to experience or adjusted according to the actual road condition of the vehicle or the screening requirement. Alternatively, the method of adjusting the primary screen radius may be as described below with reference to the embodiments shown in FIGS. 4-5. The second filtering rule may include: the included angle between the centroid connecting line vector of the two vehicles and the relative motion track vector of the two vehicles is an obtuse angle or a right angle, and the centroid distance of the two vehicles is larger than the preset early warning radius. When the included angle between the centroid connecting line vector of the two vehicles and the relative motion track vector of the two vehicles is an acute angle, the two vehicles are considered to have the possibility of collision, and when the included angle between the centroid connecting line phasor of the two vehicles and the relative motion track vector is an obtuse angle or a right angle, one vehicle can be judged to be far away from the other vehicle, so that the possibility of collision is low. Optionally, whether an included angle between a centroid connecting line vector of the two vehicles and a relative motion track vector of the two vehicles is an obtuse angle or a right angle can be judged by whether a vector product of the centroid connecting line vector of the two vehicles and the relative motion track vector of the two vehicles is less than or equal to 0, if the included angle is less than 0, the included angle is an obtuse angle, if the included angle is equal to 0, the included angle is a right angle, if the included angle is greater than zero, the included angle is an acute angle, and if the included angle is equal

Or a variation of the formula, wherein

The relative motion track vector of the vehicle B relative to the vehicle A is shown. In addition, the absolute value of the centroid connecting line vector of the two vehicles, namely the centroid distance of the two vehicles can be compared with the preset early warning radius, when the centroid distance of the two vehicles is larger than the early warning radius, the two vehicles are considered to be far away, the possibility of collision is low, and when the centroid distance of the two vehicles is smaller than or equal to the early warning radius, the two vehicles are considered to be close, and the possibility of collision is high. The mode of judging the centroid distance and the preset early warning radius can be through a formula

Or a variant thereof, wherein R_wIndicating the radius of the warning. Optionally, the preset early warning radius may be determined by a manual setting, or by referring to a preliminary screening radius, or by determining according to the following embodiment of fig. 6, which is not limited in this embodiment. The third filtering rule may include: the driving speed of the host vehicle is greater than a preset safe speed-per-hour threshold value, and the relative driving speed of the distant vehicle relative to the host vehicle is greater than the safe speed-per-hour threshold value, wherein the safe speed-per-hour threshold value can be set manually or according to road conditions, and can be set to 10KM/h, for example. When the running speed of the host vehicle is less than or equal to the safe speed per hour threshold value and the relative running speed of the distant vehicle relative to the host vehicle is less than or equal to the safe speed per hour threshold value, the possibility that the two vehicles collide at the speed is considered to be lower; when the running speed of the host vehicle is greater than the safe speed per hour threshold value, the vehicle runs faster, or the relative running speed of the distant vehicle relative to the host vehicle is greater than the safe speed per hour threshold value, the possibility that the two vehicles collide is considered to be higher. In the third screening condition, as to the description that the centroid distance of the two vehicles is greater than the warning radius, reference may be made to the description in the second screening condition.

In one embodiment, the vehicle information may include at least one of a driving speed, a driving acceleration, a yaw angle, and a vehicle speed direction angle for characterizing a driving state of the vehicle, and a centroid coordinate, a front wheel axis, a rear wheel axis, and a front wheel rotation angle for characterizing physical attribute information of the vehicle. Optionally, a rear wheel corner, and a perpendicular distance from the front wheel axis and the rear wheel axis, respectively, according to the centroid coordinate may also be included.

In an embodiment, one possible implementation manner of step S102 in the embodiment shown in fig. 2 may further include: respectively substituting the vehicle information of the main vehicle and the vehicle information of the remote vehicle into a kinematic bicycle model to obtain a motion equation of the main vehicle and a motion equation of the remote vehicle, and determining the vehicle operation parameters according to the motion equation of the main vehicle and the motion equation of the remote vehicle; wherein the vehicle operating parameters include: at least one of a centroid connecting line vector of the main car and the distant car, a centroid distance of the main car and the distant car, a relative motion trail vector of the distant car, a running speed of the main car, and a running speed of the distant car.

Specifically, since the vehicle operating parameters include: at least one of a centroid connecting line vector of the main vehicle and the far vehicle, a centroid distance of the main vehicle and the far vehicle, a relative motion track vector of the far vehicle, a running speed of the main vehicle and a running speed of the far vehicle, so that the computer equipment brings the acquired vehicle information of the main vehicle into the kinematics bicycle model to obtain a motion equation of the main vehicle and brings the vehicle information of the far vehicle into the kinematics bicycle model to obtain a motion equation of the far vehicle. Alternatively, the kinematic bicycle model can be expressed by the following formula or formula variations:

as can be seen from fig. 2a, x and y represent coordinates of the center of mass of the vehicle under the inertial coordinates provided by the GPS, v represents the traveling speed of the vehicle, and a represents the traveling acceleration of the vehicle, which maintains the same direction as the traveling speed of the vehicle in the kinematic bicycle model, respectively. Psi is the yaw angle of the vehicle, beta is the vehicle speed heading angle, l_rAnd l_fRepresenting the vertical distance of the vehicle's centroid coordinate from its rear and front wheel axes, respectively._fRepresenting the angle of rotation of the front wheels of the vehicle, which can be calculated by multiplying the steering wheel angle by the gear ratio, assuming that the rear wheels of most vehicles are not steerable_rIs 0.

And respectively substituting the vehicle information of the main vehicle and the vehicle information of the remote vehicle into the discretized kinematic bicycle model to obtain a motion equation of the main vehicle and a motion equation of the remote vehicle, wherein A represents the main vehicle, and B represents the remote vehicle. Alternatively, the equation of motion of the host vehicle at time t may be expressed by the following equation or a variant of the equation:

when n is 0:

likewise, the equation of motion of the remote vehicle at time t may be expressed by the following equation or a variation of the equation:

when n is 0:

the subscripts A and B in the embodiments of the present application represent respective parameters, coordinates A (x), of the host vehicle and the remote vehicle, respectively_A,y_A) And coordinates B (x)_B,y_B) Representing the coordinates of the center of mass of vehicle a and vehicle B, respectively.

Then, the computer device determines the vehicle operation parameters at each moment according to the motion equation of the main vehicle and the motion equation of the far vehicle. In the embodiment of the present application, point a may be regarded as a reference point of relative motion and kept still, and a motion trajectory of B with respect to point a is calculated, as shown in fig. 2B and fig. 2c, fig. 2B and fig. 2c are schematic diagrams of relative motion of two vehicles at a first time and a time n, respectively, and a travel speed and a travel acceleration expression of the relative motion are as follows:

and coordinates B of the distant vehicle relative to the host vehicle at the time t_tFurther obtaining the relative motion track vector at the first moment

The expression of (a) is:

or a variation of this equation. Where Δ t is the time interval.

In this embodiment, the vehicle operation parameters include: the method comprises the steps that at least one of a centroid connecting line vector of a main vehicle and a far vehicle, a centroid distance of the main vehicle and the far vehicle, a relative motion track vector of the far vehicle, a running speed of the main vehicle and a running speed of the far vehicle is obtained, so that computer equipment brings vehicle information of the main vehicle and vehicle information of the far vehicle into a discretized kinematics bicycle model respectively to obtain a motion equation of the main vehicle and a motion equation of the far vehicle, then vehicle running parameters of all moments are determined according to the motion equation of the main vehicle and the motion equation of the far vehicle, estimation of vehicle running tracks is further achieved, the running tracks of vehicles at different moments can be screened for vehicles to be pre-warned, and screening is further more accurate.

In an embodiment, the filtering rule may include a first filtering rule, and one possible implementation manner of the S103 may be: and determining the remote vehicle with the centroid distance meeting the first screening condition as a safe vehicle so as to obtain other vehicles to be pre-warned. Specifically, when the centroid distance is greater than the primary screening radius, the computer device determines that the distance between the far vehicle and the main vehicle is far, and the collision risk does not exist, so that the far vehicle is taken as a safe vehicle, and the safe vehicle does not enter the next early warning process; and if the distance of the center of mass is larger than the primary screening radius, determining that the distance between the far vehicle and the main vehicle is in collision risk, and taking the far vehicle as the vehicle to be pre-warned, wherein the vehicle can enter a pre-warning process. In this embodiment, through the long car screening that is greater than the primary screen radius with the barycenter distance of two cars, with all the other long cars as treating the early warning vehicle to get into early warning flow on next step, because the vehicle distribution that the above-mentioned primary screen radius can combine and the actual conditions of road, consequently this screening mode calculated amount reduces greatly, has reduced the consumption of system's resource and has improved the screening efficiency while, its screening accuracy is high.

In an embodiment, the filtering rule may include a second filtering rule, and another possible implementation manner of the S103 may also be shown in fig. 3, and specifically may include:

s201, determining an included angle between the centroid connecting line vector and the relative motion track vector according to the centroid connecting line vector and the relative motion track vector.

For the specific process and parameter description in this step, reference may be made to the detailed description of the foregoing second screening rule, which is not described herein again.

S202, determining safe vehicles by the remote vehicles of which the centroid connecting line vectors and the relative motion track vectors and the centroid distances both meet the second screening rule, and accordingly obtaining the vehicles to be pre-warned.

Specifically, the computer device may determine that an included angle between the centroid connecting line vector and the relative motion trajectory vector is an obtuse angle or a right angle, and the distant vehicle with the centroid distance greater than the early warning radius of the two vehicles is a safe vehicle to be screened, and take the rest distant vehicles as the vehicles to be early warned.

In this embodiment, the computer device can determine the included angle between the centroid link vector and the relative motion track vector according to the centroid link vector and the relative motion track vector, and determine a remote vehicle in which the included angle between the centroid link vector and the relative motion track vector and the centroid distance satisfy the second screening rule as a safe vehicle, thereby using other remote vehicles as a vehicle to be pre-warned, and therefore, outside a certain pre-warning range, screening the safe vehicle without collision risk by judging the motion track of the two vehicles at a future moment, and using other remote vehicles as the vehicle to be pre-warned, so that the screening of the vehicle to be pre-warned can be performed in combination with the motion track of the vehicle, which is more accurate and has pertinence, and further the pre-warning accuracy of the vehicle is higher.

In an embodiment, the filtering rule may include a third filtering rule, and yet another possible implementation manner of the S103 may further include: and determining the remote vehicles of which the centroid distance, the running speed of the main vehicle and the relative running speed meet the third screening rule as safe vehicles so as to obtain other vehicles to be pre-warned. Specifically, the computer device may determine that the distance between the centers of mass is greater than the warning radius, and when the traveling speed of the host vehicle is less than or equal to the safe speed per hour threshold and the relative traveling speed of the distant vehicle with respect to the host vehicle is less than or equal to the safe speed per hour threshold, the distant vehicle is determined as a safe vehicle to be screened because the traveling speed of the distant vehicle is low with respect to the host vehicle and the traveling speed of the host vehicle is low and there is no risk of collision with the host vehicle outside a certain warning range, and the other vehicles are used as vehicles to be warned to enter a warning. In this embodiment, the computer device can determine the distance of the center of mass, the traveling speed of the main vehicle, and the distant vehicle whose relative traveling speed satisfies the third screening rule as the safe vehicle, so that the distant vehicle with a slower traveling speed or a slower relative traveling speed can be screened out by judging the traveling speeds and the relative traveling speeds of the two vehicles outside a certain early warning range, and the distant vehicle with a faster traveling speed or a faster relative traveling speed of the two vehicles is left as the vehicle to be early warned. By adopting the method, the safe vehicles which obviously do not have collision risks can be screened out by combining with the speed of the running speed, the vehicles to be pre-warned are left, the frequent pre-warning under the condition that the collision risk is small, namely the main vehicle runs at a very low speed or the two vehicles run at a relatively low speed, is avoided, the invalid pre-warning is effectively reduced, the screening of the vehicles to be pre-warned is more accurate, and the pre-warning accuracy of the vehicles is higher.

In one embodiment, the screening rules may further include a first screening rule and a second screening rule, where the first screening rule is used to screen a part of the safe vehicles, and then the second screening rule is used to screen a part of the safe vehicles in the remaining remote vehicles. The order of screening by the first screening rule and the second screening rule is not limited. Optionally, the screening rules may further include a second screening rule and a third screening rule, or include a first screening rule and a third screening rule, and may further include a first screening rule, a second screening rule and a third screening rule, where an order of using the first screening rule, the second screening rule and the third screening rule is not limited.

Fig. 4 is a schematic flow chart of a vehicle screening method to be warned according to another embodiment. The present embodiment relates to a possible implementation manner of determining a preliminary screening radius by a computer device, and optionally, on the basis of the foregoing embodiments, the implementation manner includes:

s301, obtaining the initial number of the distant vehicles around the main vehicle according to the initial primary screening radius.

Specifically, the computer device may acquire the IDs of the surrounding distant vehicles through the V2X system, and may determine the distance of each distant vehicle from the host vehicle according to the positioning information, thereby counting the initial number of distant vehicles in the initial screening radius. Alternatively, the initial prescreening radius may be a fixed value, for example set to 500 meters. Then first the computer device counts the initial number of faraway cars within 500 meters of the perimeter.

S302A, if the initial number is smaller than or equal to a preset far vehicle number threshold value, determining the initial primary screening radius as the primary screening radius; the primary screening radius is larger than or equal to a preset primary screening radius threshold value.

Specifically, when the initial number is less than or equal to the preset far vehicle number threshold, the initial primary screening radius may be determined as the primary screening radius. It should be noted that the preliminary screening radius cannot be smaller than a preset preliminary screening radius threshold, and the preliminary screening radius threshold may be a limit value in the national standard, for example, 300 meters. The threshold value of the number of the distant vehicles is a set value, for example, 50 vehicles.

S302B, if the initial number is larger than the threshold value of the number of the remote vehicles, reducing the initial primary screening radius, and obtaining the adjustment number of the remote vehicles within the reduced initial primary screening radius range; judging whether the adjustment quantity is smaller than or equal to the threshold value of the remote vehicle quantity; if so, determining the reduced initial primary screening radius as the primary screening radius; if not, reducing the initial primary screening radius again until the number of the far vehicles in the range of the initial primary screening radius is smaller than or equal to the threshold value of the number of the far vehicles, and taking the initial primary screening radius obtained by the last reduction as the primary screening radius.

Specifically, when the initial number is greater than the threshold value of the number of the distant vehicles, since the number of the distant vehicles is too large, the calculated amount is too large, the initial preliminary screening radius can be reduced, the adjusted number of the distant vehicles within the reduced range of the initial preliminary screening radius is obtained again, and then whether the adjusted number is less than or equal to the threshold value of the number of the distant vehicles is judged. If the adjusted number of the far vehicles is less than or equal to the threshold value of the number of the far vehicles, determining the reduced initial primary screening radius as the primary screening radius; if the adjusted number of the far vehicles is still larger than the threshold value of the number of the far vehicles, the initial primary screening radius is reduced again until the number of the far vehicles in the range of the initial primary screening radius is smaller than or equal to the threshold value of the number of the far vehicles, and then the initial primary screening radius obtained by the last reduction is used as the primary screening radius.

Optionally, the step for adjusting the preliminary screening radius is not limited in this embodiment, and may be 10 meters, or may be 30 meters or other steps.

In the embodiment, the computer equipment can acquire the initial number of the distant cars around the main car according to the initial primary screening radius, and reduce the initial primary screening radius through iteration until the adjustment number of the distant cars in the initial primary screening radius is less than or equal to the threshold value of the number of the distant cars, and take the initial primary screening radius obtained by reducing for the last time as the final primary screening radius, so that the proper number of the distant cars can be determined according to the density degree of the car distribution, and the next early warning flow or screening flow can be carried out.

Fig. 5 is a schematic flow chart of a vehicle screening method to be warned according to another embodiment. In one embodiment, another possible implementation of the computer device determining the prescreening radius may be as shown in fig. 5, including:

s401, acquiring road information corresponding to a road where the main vehicle is located; the road information is used for representing the density degree of vehicle distribution on the road.

Specifically, the computer device may interact with the host vehicle and the roadside unit, thereby obtaining road information via the roadside unit. The road information can represent the density of vehicle distribution on the road, for example, if the road is an urban road, it is determined that the vehicle distribution on the road is dense, and if the road is an expressway, it is determined that the vehicle distribution on the road is sparse.

S402, adjusting a preset initial primary screening radius according to the road information to obtain the primary screening radius; the primary screening radius is larger than or equal to a preset primary screening radius threshold value.

Specifically, the computer device may increase or decrease a preset initial preliminary screening radius according to the road information, thereby obtaining a preliminary screening radius; the minimum value of the primary screening radius can be defined as described above, and is not described herein.

Optionally, an implementation manner of this step may include: if the road information is a dense vehicle road, reducing the initial primary screening radius to obtain the primary screening radius; and if the road information is a vehicle sparse road, increasing the initial primary screening radius to obtain the primary screening radius. Specifically, when the road information is a road with dense vehicles, the vehicles are considered to be likely to run slowly, so that the initial primary screening radius can be reduced, and the excessive number of remote vehicles entering the next process can be avoided; when the road information is a vehicle sparse road, the vehicle is considered to be likely to run faster, so that the initial primary screening radius can be increased, and untimely early warning caused by too high running speed is avoided. In this implementation, through reduce initial preliminary screening radius on vehicle dense road to and on vehicle sparse road, increase initial preliminary screening radius, finally obtain the reasonable preliminary screening radius that is fit for current road information, thereby make when guaranteeing effective early warning, reasonable control calculated amount makes vehicle screening more effective, and its degree of accuracy is higher.

Fig. 6 is a schematic flow chart of a vehicle screening method to be warned according to another embodiment. In one embodiment, one possible implementation of the computer device to determine the warning radius may be as shown in fig. 6, including:

s501, dividing the area around the main vehicle into a plurality of sub-areas according to the center of mass coordinates of the main vehicle, the axis of the front wheel of the main vehicle and the axis of the rear wheel of the main vehicle.

Specifically, the computer device may divide the area around the host vehicle into a plurality of sub-areas according to the coordinates of the center of mass of the host vehicle, the distance and the orientation of the front wheel axis of the host vehicle and the rear wheel axis of the host vehicle, for example, it may be divided into left and right areas according to the coordinates of the center of mass and the heading direction of the vehicle head, and may be divided into front, middle, and rear areas according to the front wheel axis and the rear wheel axis. Optionally, the multiple sub-regions may also include, as shown in fig. 6 a: a right front sub-region, a right side sub-region, a front right sub-region, a front left sub-region, a left side sub-region, a rear left sub-region, a rear right sub-region, and a rear right sub-region.

S502, determining the included angle of the far vehicle relative to the head direction of the main vehicle according to the head direction of the main vehicle and the head direction of the far vehicle.

Specifically, the computer device can also respectively obtain the head direction of the main vehicle and the head direction of the far vehicle according to the vehicle information of the main vehicle and the far vehicle, and then further determine the included angle between the head directions of the two vehicles.

S503, determining the early warning radius according to the distribution of the centroid coordinates of the remote vehicles in the sub-area and the included angle of the vehicle head direction.

Specifically, the computer device can also determine the corresponding early warning distance according to which sub-area of the main car the centroid coordinate of the far car is distributed in and in combination with the direction included angle of the car head.

Optionally, the early warning radius may be determined according to a correspondence between the sub-region, the early warning radius determination formula, and the vehicle head direction included angle. Optionally, the corresponding relationship between the sub-area, the early warning radius determination formula, and the vehicle head direction included angle may be a one-to-one corresponding relationship, a one-to-many relationship, or a many-to-many relationship, and this embodiment is not limited. Optionally, the corresponding relationship between the sub-area, the early warning radius determination formula, and the vehicle head direction included angle may also be as shown in table 1 below.

TABLE 1

Wherein the content of the first and second substances,

R_w＝R_w6＝L_f,A+L_r,B

R_w＝R_w7＝L_f,A+L_f,B

R_w＝R_w11＝L_r,A+L_f,B

R_w＝R_w12＝L_r,A+L_r,B

wherein R is_wTo warn of radius, θ_refIs included angle of the headstock direction, L_f,AIs the vertical distance between the coordinate of the center of mass of the main vehicle and the axis of the front wheel of the main vehicle, L_r,AIs the vertical distance between the coordinate of the center of mass of the main vehicle and the axis of the rear wheel of the main vehicle, L_f,BIs the perpendicular distance between the barycentric coordinate of the remote vehicle and the axis of the front wheel of the remote vehicle, L_r,BIs the perpendicular distance between the barycentric coordinate of the remote vehicle and the axis of the rear wheel of the remote vehicle, W_AWidth of the main car, W_BThe width of the faraway car; and deltal is a reserved distance.

As shown in FIG. 6b, when the point A of the barycenter of the host vehicle is the origin, the positive direction of the X axis is kept in the same direction as the direction of the head of the host vehicle, a new coordinate system relative to the host vehicle can be obtained, the angle setting of the new coordinate system is counterclockwise positive, the positive direction of the Y axis is 0 degree, and the angle between the far vehicle and the direction of the head of the host vehicle is 120 degrees in FIG. 6 b. In order to calculate the distance between two vehicles just colliding, the main vehicle and the far vehicle are both regarded as rectangles, taking the far vehicle in fig. 6b as an example of the far vehicle being positioned at the front right of the main vehicle, the two vehicles are in point contact at the upper right corner C of the main vehicle, | AB | is the distance connecting the centers of mass of the two vehicles, and | AB | is known from the figure<L AC + BC. Therefore, | AC | + | BC | can be employed as the warning distance R for safety reasons_w. Since | AC | is a constant and the maximum value of | BC |, is

So it can be known that

In addition, according to the difference of the included angles of the two vehicles in the direction of the vehicle heads, the vehicle can know

If the early warning distance is too large, unnecessary early warning and false warning can be generated, as shown in fig. 6c, two vehicles run in the same direction on adjacent lanes, the two vehicles are still considered to run in the same direction when the included angle between the head directions of the two vehicles is less than or equal to 30 degrees, the far vehicle B is on the right side of the main vehicle A, and the transverse distance of the two vehicles is used as the early warning distance at the moment, namely the early warning distance

Similarly, based on the change of the direction angles of the two vehicles, we can determine the following formula:

where Δ L is a scratch-resistant reserve distance which can be defined by the user himself, optionally it can be set to 1 meter. It should be noted that the two vehicles travel in opposite directions.

The corresponding relation shown in the table 1 is adopted to determine the early warning radius, and the corresponding early warning radius can be selected by combining the sub-region where the remote vehicle is located and the included angle between the vehicle head directions of the two vehicles, so that the screening of the vehicles to be early warned can be more accurate, and the effectiveness is higher.

In the embodiment, the computer equipment divides the area around the main car into a plurality of sub-areas according to the barycenter coordinate of the main car, the front wheel axis of the main car and the rear wheel axis of the main car, then determines the head direction included angle of the remote car relative to the main car according to the head direction of the main car and the head direction of the remote car, and finally determines a reasonable early warning radius according to the distribution of the barycenter coordinate of the remote car in the sub-areas and the head direction included angle, so that the early warning radius can be combined in different directions of the remote car and the main car, and the conditions of different running directions, the early warning radius is more reasonable, and the screening of the vehicles to be early warned is more accurate.

The method for screening the vehicle to be early-warned is described in detail in the embodiment, the computer device can also early warn the vehicle after screening the vehicle to be early-warned, and the specific process of vehicle early warning is described in detail in the embodiment.

Fig. 7 is a flowchart illustrating a vehicle warning method according to an embodiment. The embodiment relates to a specific process of adopting a kinematic bicycle model to carry out early warning on a vehicle to be early warned with a collision risk by computer equipment according to vehicle information of a main vehicle and the vehicle to be early warned. Specifically, as shown in fig. 7, the vehicle warning method includes:

s601, acquiring vehicle information of a main vehicle and vehicle information of a vehicle to be early-warned; the vehicle information is used for representing the driving state and the physical attribute information of the vehicle.

Specifically, the specific manner in which the computer device in this step acquires the vehicle information of the host vehicle and the vehicle to be warned may be referred to as detailed description in S101 in the foregoing embodiment, and details are not repeated here.

S602, determining whether a closest distance point closest to the main vehicle exists on the motion trail of the vehicle to be early warned or not by adopting a kinematics bicycle model according to the vehicle information of the main vehicle and the vehicle information of the vehicle to be early warned.

Specifically, the computer device may determine the operating characteristics of the host vehicle and the vehicle to be warned according to the vehicle information of the host vehicle and the vehicle information of the vehicle to be warned, and the computer device may determine whether a closest distance point closest to the host vehicle exists on the motion trajectory of the vehicle to be warned according to the operating characteristics of the vehicle. For example, it may be determined by determining whether the projection point of the host vehicle in the direction of the moving track of the vehicle to be pre-warned falls on the moving track vector of the vehicle to be pre-warned or whether the distance is smaller than a certain distance. When the projection point of the main vehicle in the running track direction of the vehicle to be pre-warned falls on the running track vector of the vehicle to be pre-warned, or the distance is smaller than a certain distance, determining that the closest distance point with the nearest distance to the main vehicle exists on the running track of the vehicle to be pre-warned; when the projection point of the main vehicle in the running track direction of the vehicle to be pre-warned does not fall on the running track vector of the vehicle to be pre-warned and the distance exceeds a certain distance, determining that the closest distance point closest to the main vehicle does not exist on the running track of the vehicle to be pre-warned.

And S603, if the vehicle collision time exists, determining the collision time of the vehicle to be pre-warned and the main vehicle according to the vehicle motion parameters.

Specifically, when the closest distance point closest to the host vehicle exists on the motion trail of the vehicle to be early-warned, it can be determined that the vehicle to be early-warned has the risk of collision with the host vehicle. Optionally, the vehicle motion parameter may be a parameter determined according to a kinematic bicycle model, which can represent motion characteristics of the host vehicle and the vehicle to be warned, and also represent relative motion characteristics of the two vehicles. Therefore, the computer device estimates the collision time when the vehicle to be pre-warned runs to the nearest distance point from the current moment according to the vehicle motion parameters.

Optionally, if there is no closest distance point closest to the host vehicle on the motion trajectory of the vehicle to be early-warned, it may be determined that the vehicle to be early-warned does not collide with the host vehicle, and the computer device stops the early warning of the vehicle to be early-warned, so as to ensure the accuracy of the early warning and reduce the computation.

And S604, carrying out safety early warning on the vehicle to be early warned according to the collision time and the closest point of the distance.

Specifically, the computer device can perform safety early warning on the vehicle to be early warned according to the collision time and by combining the closest point. Optionally, the safety warning of the pre-warning vehicle can be performed by judging the collision time and the degree of urgency of collision with the closest point according to the collision time and the closest point in combination with a preset pre-warning standard. For example, when the collision time is short and the nearest distance point is close to the vehicle to be collided, determining that the vehicle to be pre-warned carries out emergency pre-warning; otherwise, carrying out normal early warning. Optionally, the early warning mode in this embodiment may be a voice mode, may also be a warning light, and may also be a braking instruction taken for the early warning mode, which is not limited to this embodiment.

In the embodiment, the vehicle information can represent the running state and the physical attribute information of the vehicle, so that the computer equipment can determine the running characteristics of the two vehicles according to the vehicle information of the main vehicle and the vehicle information of the vehicle to be pre-warned and by adopting the kinematic bicycle model. And then the computer equipment can more accurately judge whether the movement track of the vehicle to be pre-warned has the closest distance point with the nearest distance to the main vehicle or not according to the movement track of the vehicle, so that the computer equipment can accurately determine whether the vehicle to be pre-warned has the possibility of collision with the main vehicle or not, and based on the result, under the condition that the closest distance point exists on the movement track of the vehicle to be pre-warned, more accurate collision time is further determined according to accurate movement characteristics, and then the vehicle to be pre-warned is accurately pre-warned according to the collision time and the closest distance point. By adopting the method, the computer equipment adopts the kinematic bicycle model to determine the running characteristics of the two vehicles, the collision early warning of the vehicles is carried out without depending on information such as road curvature and the like in a map, and the method can be suitable for roads with any curvature, so that the universality of the method is greatly improved, the accuracy of vehicle track prediction is greatly improved, the early warning accuracy is further greatly improved, and the vehicles run more safely.

Fig. 8 is a schematic flowchart of a vehicle warning method according to another embodiment. In one embodiment, the computer device determining whether a closest distance point closest to the host vehicle exists on the motion trail of the vehicle to be warned may be as shown in fig. 8, including:

s701, respectively bringing the vehicle information of the main vehicle and the vehicle information of the vehicle to be early-warned into a discretized kinematic bicycle model to obtain a motion equation of the main vehicle and a motion equation of the vehicle to be early-warned.

S702, determining the vehicle operation parameters corresponding to all the moments according to the motion equation of the main vehicle and the motion equation of the remote vehicle.

Specifically, the specific manner in which the computer device brings the vehicle information into the discretized kinematic bicycle model to obtain the motion equation of the corresponding vehicle and determines the vehicle operating parameters at each time according to the motion equation may be referred to in the foregoing description, and is not described herein again.

And S703, determining whether a closest distance point closest to the main vehicle exists on the motion trail of the vehicle to be pre-warned according to the vehicle running parameters.

Specifically, the computer device may determine whether a closest distance point closest to the host vehicle exists on the motion trajectory of the vehicle to be pre-warned according to the vehicle operation parameters. For example, it may be that the vehicle to be warned at the current time is within a warning range preset around the host vehicle, or the distance of the trajectory traveled by the vehicle to be warned at the current time exceeds the distance between the host vehicle and the vehicle to be warned at the current time.

Optionally, a possible implementation manner of this step S703 further includes:

if the vehicle operation parameters at the current moment meet at least one of the preset condition sets, determining that a closest distance point with the shortest distance to the main vehicle exists on the motion trail of the vehicle to be pre-warned; if the vehicle operation parameters at the current moment do not meet all the conditions in the condition set, continuing to calculate the vehicle operation parameters at the next moment, and determining that the closest distance point with the nearest distance to the main vehicle exists on the motion trail of the vehicle to be warned at the next moment when the vehicle operation parameters meet at least one of the condition set; and when the vehicle operation parameter does not meet all the conditions in the condition set, continuously and iteratively calculating the vehicle operation parameter at the next moment until the vehicle operation parameter meets at least one condition in the condition set or the iteration number is greater than a preset iteration number threshold. Wherein the condition set includes a correlation between the vehicle operating parameter and a preset early warning radius.

In this implementation manner, the computer device can determine that a closest distance point closest to the host vehicle exists on the motion trajectory of the vehicle to be warned when the vehicle operation parameter at the current time meets at least one of the preset condition sets, and perform the warning until the closest distance point is found through iterative computation when the vehicle operation parameter at the current time does not meet all conditions in the condition sets, so as to accurately judge whether the vehicle has the possibility of collision or not, or stop the warning when the iteration number is greater than a preset iteration number threshold, so as to reduce the calculation amount of the warning, and further reduce resource consumption.

In one embodiment, the vehicle operating parameters include: at least one of a centroid connecting line vector of the two vehicles, a centroid distance of the two vehicles, a relative motion track vector of the far vehicle relative to the main vehicle, a running speed of the main vehicle and a running speed of the far vehicle. Optionally, the vehicle operating parameters may further include: at least one of the travel acceleration of the host vehicle and the travel acceleration of the distant vehicle.

In one embodiment, the set of conditions may include at least one of the following conditions:

the first condition is that: the distance between the mass centers of the main vehicle and the vehicle to be early-warned at the current moment is smaller than the preset early-warning radius.

Specifically, the first condition may be a formula

Or a deformation characterization of the formula.

The second condition is that: the absolute value of the relative motion track vector of the vehicle to be pre-warned at the current moment is greater than or equal to the centroid distance of the main vehicle and the vehicle to be pre-warned at the current moment.

Specifically, the second condition may be a formula

Or a deformation characterization of the formula.

A third condition: and the sum of the absolute values of the relative motion track vectors of the vehicles to be pre-warned at each moment is greater than or equal to the centroid distance of the main vehicle and the vehicles to be pre-warned at the current moment.

Specifically, the third condition may be a formula

Or a variant expression of the formula.

A fourth condition: the projected distance of the host vehicle at the previous time is less than or equal to the projected distance of the host vehicle at the current time.

Specifically, the fourth condition may adopt the formula DCPA_n-1≤DCPA_nOr a variant expression of the formula. Wherein, DCPA_n-1And DCPA_nThe projection distance between the projection point of the main vehicle in the track vector direction of the vehicle to be pre-warned and the barycenter coordinate of the main vehicle at the previous moment and the next moment respectively. Wherein

And is

A fifth condition: and the adjacent motion track vector of the vehicle to be pre-warned at the current moment relative to the previous moment and the barycenter connecting line vector of the main vehicle and the vehicle to be pre-warned at the previous moment form an obtuse angle or a right angle.

Specifically, the fifth condition may adopt a formula

Or a variant expression of the formula.

In this embodiment, the condition set may include a first condition, a second condition, a third condition, a fourth condition, and a fifth condition, and the five conditions include interrelations of vehicle motion parameters, so that when the vehicle motion parameters meet any one of the five conditions, it is determined that the closest distance point has been found, so that the risk of collision can be determined more accurately and comprehensively from the angle of each parameter included in the vehicle motion parameters, and then the vehicle is warned according to the closest distance point, so that the vehicle is warned more accurately.

Alternatively, on the basis of the foregoing embodiment, if the condition set includes a fourth condition, a method for determining the projection distance in the fourth condition may be as shown in fig. 9, and includes:

s801, projecting the centroid coordinate of the main vehicle on the relative motion track vector of the vehicle to be early-warned to obtain a projection point coordinate.

In particular, see fig. 2b and 2C, wherein C₁And C_nRespectively, the projection point coordinates of the first time and the n time.

S802, determining the projection distance according to the projection point coordinates and the barycenter coordinates of the main vehicle.

Specifically, taking the distance between the projection point coordinate and the centroid coordinate of the host vehicle as the projection distance, optionally, a projection vector of the projection point coordinate to the centroid coordinate of the host vehicle may also be obtained.

In this embodiment, the computer device may project the centroid coordinate of the main vehicle on the relative motion trajectory vector of the vehicle to be pre-warned to obtain the projection point coordinate, and obtain the projection distance according to the projection point coordinate and the centroid coordinate of the main vehicle, and then may determine whether the closest distance corresponding to the closest distance point is obtained from the projection distance, so as to more accurately determine whether there is a collision risk, thereby making the collision pre-warning of the vehicle more accurate.

Alternatively, on the basis of the foregoing embodiment, one possible implementation manner of the step S103 of "determining the collision time of the vehicle to be warned colliding with the host vehicle according to the vehicle motion parameter" may be as shown in fig. 10, and includes:

and S901, judging whether the vehicle motion parameters meet the fourth condition or the fifth condition.

And S902, 902A, if yes, determining the collision distance according to the vehicle motion parameters at the previous moment.

In particular, the computer device may be based on a formula

Or a variation of this formula to determine the collision distance

S902B, if not, determining the collision distance according to the vehicle motion parameters at the current moment.

In particular, the computer device may be according to

Or a variation of this formula to determine the collision distance

And S903, determining the collision time according to the collision distance, the relative running speed of the vehicle to be early-warned relative to the main vehicle at the current moment and the previous moment, the iteration times and the time interval.

Specifically, the computer device may determine the collision time based on the collision distance in combination with the traveling speed of the host vehicle, the relative traveling speeds of the vehicle at the current time and the previous time, the current number of iterations, and the relationship between the time intervals. The time interval may be a time step used in discretization, that is, a time length between each time and an adjacent time, and the vehicle may be considered to be in uniform acceleration linear motion in each time step.

Alternatively, this step may be represented by a formula

Or the deformation of the formula yields the collision time ttc, where Δ t is the time interval and n is the number of iterations, i.e. the sequence at the current time.

In this embodiment, the computer device is capable of indicating that the vehicle to be warned has started to get away from the main vehicle at this time when the vehicle motion parameter satisfies the fourth condition or the fifth condition, so that the distance at the previous time is taken as the closest distance between the two vehicles; when the vehicle motion parameters do not meet the fourth condition and the fifth condition, the state that the vehicle to be pre-warned is closer to the main vehicle is described, therefore, the distance at the current moment is taken as the closest distance between the two vehicles, so that a more accurate closest distance is obtained, and then according to the closest distance, the collision time is determined by combining the relative driving speed, the iteration times and the time interval of the vehicle to be pre-warned relative to the main vehicle at the current moment and the previous moment, so that the determined collision time is more accurate, and the collision pre-warning of the vehicle is more accurate.

In an embodiment, one possible implementation manner of the S104 may include: determining the safety early warning level of the vehicle to be early warned according to a preset maximum early warning level, the collision time, the time interval, the early warning radius, a preset safety factor and the shortest relative distance; the shortest relative distance is a distance between a closest distance point and the centroid coordinates of the host vehicle.

In particular, the computer device may be based on a formula

Or the deformation of the formula determines the safety precaution level W, wherein W_maxAt the maximum warning level, R_wTo warn radius, S is safety factor, DCPA_minIs the shortest relative distance. The shortest relative distance is the distance between the closest distance point and the centroid coordinate of the vehicle to be early-warned. Alternatively, the maximum warning level may be defined for a considered user, which may be a positive integer, e.g. 10, i.e. characterizing a total of 10 levels of warning. The safety coefficient can take different values along with the danger degrees of different collision scenes (forward collision and intersection collision), the more dangerous places take larger values, and the danger degree of the scenes can be defined by users. For the condition that the centroid distance is smaller than the early warning radius, the system can skip the subsequent iteration process, and directly set ttc to be 0, so that the calculated early warning level is directly the maximum early warning level.

The iterative algorithm provided by the scheme can be verified through a scene that the vehicle A and the vehicle B are assumed to do uniform acceleration motion along the same straight line and the steering wheel turning angles are both 0 degree, and beta exists at the moment_A＝β _B0 and psi_A＝ψ_Bψ is a constant. At this time, the magnitude and direction of the acceleration of the two vehicles are constant, so the displacement coordinate of the vehicle B relative to the vehicle a can be expressed as:

due to the existence of

And

so the above relative displacement expression is taken from t₁To t_nAnd accumulating to obtain:

the expression is matched with a relative motion track calculation formula of the uniform acceleration linear motion, and the preset scene is met, so that the scheme can be reasonably applied.

In this embodiment, the computer device can determine the safety early warning level of the vehicle to be early warned according to the preset maximum early warning level, the collision time, the time interval, the early warning radius, the preset safety factor and the shortest relative distance, wherein the shortest relative distance is the distance between the closest distance point and the centroid coordinate of the main vehicle, so the computer device can perform early warning according to the level according to the preset large early warning level, the time interval and the preset safety factor based on the accurate collision time, and combines the reasonably set early warning radius and the shortest relative distance.

In an embodiment, the determining of the warning radius may include:

dividing an area around the host vehicle into a plurality of sub-areas according to the coordinates of the center of mass of the host vehicle, the axis of a front wheel of the host vehicle and the axis of a rear wheel of the host vehicle;

determining the included angle of the far vehicle relative to the head direction of the main vehicle according to the head direction of the main vehicle and the head direction of the far vehicle;

and determining the early warning radius according to the distribution of the centroid coordinates of the remote vehicles in the sub-area and the included angle of the vehicle head direction.

In one embodiment, the plurality of sub-regions includes: a right front sub-region, a right side sub-region, a front right sub-region, a front left sub-region, a left side sub-region, a rear left sub-region, a rear right sub-region, and a rear right sub-region.

In one embodiment, the determining an early warning radius corresponding to the distant vehicle according to the distribution of the centroid coordinates of the distant vehicle in the sub-area and the included angle of the direction of the vehicle head includes:

and determining the early warning radius according to the corresponding relation among the sub-area, the early warning radius determination formula and the included angle of the vehicle head direction.

In one embodiment, the corresponding relationship between the sub-area, the early warning radius determination formula and the vehicle head direction included angle is as shown in table 1.

Specifically, in the vehicle early warning process, the method for determining the early warning radius may refer to the description of the early warning radius in the method for screening the vehicle to be early warned, and is not described herein again.

Alternatively, in the vehicle warning process, the method for determining the warning radius may refer to the description in the foregoing embodiment.

It should be understood that although the various steps in the various embodiments described above are not necessarily performed in the order discussed. The steps are not performed in the exact order shown and described, and may be performed in other orders, unless explicitly stated otherwise. Moreover, the warning method in the above embodiments may include multiple sub-steps or multiple stages, which are not necessarily performed at the same time, but may be performed at different times, and the order of performing the sub-steps or the stages is not necessarily sequential, but may be performed alternately or alternately with other steps or at least a part of the sub-steps or the stages of other steps.

In one embodiment, as shown in fig. 11, there is provided a vehicle early warning apparatus including:

the acquiring module 100 is used for acquiring vehicle information of a main vehicle and vehicle information of a vehicle to be early-warned; the vehicle information is used for representing the driving state and physical attribute information of the vehicle;

the processing module 200 is configured to determine whether a closest distance point closest to the host vehicle exists on a motion trajectory of the vehicle to be early warned by using a kinematic bicycle model according to the vehicle information of the host vehicle and the vehicle information of the vehicle to be early warned; if the vehicle to be pre-warned is in collision with the main vehicle, determining the collision time of the vehicle to be pre-warned and the main vehicle according to the vehicle motion parameters; and carrying out safety early warning on the vehicle to be early warned according to the collision time and the closest point of the distance.

In one embodiment, the processing module 200 is specifically configured to bring the vehicle information of the host vehicle and the vehicle to be warned into a discretized kinematic bicycle model respectively to obtain a kinematic equation of the host vehicle and a kinematic equation of the vehicle to be warned; determining the vehicle operation parameters corresponding to each moment according to the motion equation of the main vehicle and the motion equation of the remote vehicle; and determining whether a closest distance point closest to the main vehicle exists on the motion trail of the vehicle to be early warned according to the vehicle operation parameters.

In an embodiment, the processing module 200 is specifically configured to determine that a closest distance point closest to the host vehicle exists on a motion trajectory of the vehicle to be warned if the vehicle operation parameter at the current time meets at least one of a preset condition set; the condition set comprises the correlation between the vehicle operation parameters and preset early warning radiuses; if the vehicle operation parameter at the current moment does not meet any one of the condition sets, iteratively calculating the vehicle operation parameter at the next moment until the vehicle operation parameter meets at least one of the condition sets, or the iteration number is greater than a preset iteration number threshold.

In one embodiment, the vehicle operating parameters include: at least one of a centroid connecting line vector of the two vehicles, a centroid distance of the two vehicles, a relative motion track vector of the distant vehicle with respect to the main vehicle, a traveling speed of the distant vehicle, a traveling acceleration of the main vehicle, and a traveling acceleration of the distant vehicle.

In one embodiment, the set of conditions includes at least one of the following conditions; the first condition is that: the centroid distance between the main vehicle and the vehicle to be early-warned at the current moment is smaller than the preset early-warning radius; the second condition is that: the absolute value of the relative motion track vector of the vehicle to be pre-warned at the current moment is greater than or equal to the centroid distance of the main vehicle and the vehicle to be pre-warned at the current moment; a third condition: the sum of the absolute values of the relative motion track vectors of the vehicles to be pre-warned at each moment is greater than or equal to the centroid distance of the main vehicle and the vehicles to be pre-warned at the current moment; a fourth condition: the projection distance of the host vehicle at the previous moment is less than or equal to the projection distance of the host vehicle at the current moment; a fifth condition: and the adjacent motion track vector of the vehicle to be pre-warned at the current moment relative to the previous moment and the barycenter connecting line vector of the main vehicle and the vehicle to be pre-warned at the previous moment form an obtuse angle or a right angle.

In an embodiment, if the condition set includes the fourth condition, the processing module 200 may be further configured to project a centroid coordinate of the host vehicle on a relative motion trajectory vector of the vehicle to be pre-warned, so as to obtain a projection point coordinate; and determining the projection distance according to the projection point coordinates and the barycenter coordinates of the main vehicle.

In one embodiment, the processing module 200 is specifically configured to determine the collision distance according to the vehicle motion parameter at a previous time if the vehicle motion parameter satisfies the fourth condition or the fifth condition; if the vehicle motion parameter does not meet the fourth condition and the fifth condition, determining a collision distance according to the vehicle motion parameter at the current moment; and determining the collision time according to the collision distance, the relative running speed of the vehicle to be early-warned relative to the main vehicle at the current moment and the previous moment, the iteration times and the time interval.

In one embodiment, the processing module 200 is specifically configured to formulate a formula

Determining the collision distance

Wherein, B_n-2Is waiting for the time n-2Centroid coordinates of early warning vehicle, B_n-1Is the centroid coordinate of the vehicle to be pre-warned at the moment of n-1, A_n-1Barycentric coordinates of the principal car at time n-1, C_n-1Is the projected point coordinate at time n-1,

Determining the collision distance

Wherein, B_n-1Is the centroid coordinate of the vehicle to be pre-warned at the moment of n-1, B_nIs the barycentric coordinate of the vehicle to be pre-warned at the time n, A is the barycentric coordinate of the main vehicle at the time n, C_nIs the projected point coordinate at time n,

Determining the collision time ttc, wherein n is the number of iterations and Δ t is the time interval,

as the distance of the collision,

is the running speed of the main vehicle,

the driving speed of the vehicle to be pre-warned is obtained.

In one embodiment, the processing module 200 is specifically configured to determine a safety early warning level of the vehicle to be early warned according to a preset maximum early warning level, the collision time, the time interval, the early warning radius, a preset safety factor, and a shortest relative distance; the shortest relative distance is a distance between a closest distance point and the centroid coordinates of the host vehicle.

Determining the safety precaution level W, wherein W_maxAt the maximum warning level, R_wTo warn radius, S is safety factor, DCPA_minIs the shortest relative distance.

In one embodiment, the vehicle information includes at least one of a driving speed, a driving acceleration, a yaw angle, and a vehicle speed direction angle for characterizing a driving state of the vehicle, and a centroid coordinate, a front wheel axis, a rear wheel axis, and a front wheel rotation angle for characterizing physical attribute information of the vehicle.

In one embodiment, the apparatus may further include: the dividing module is used for dividing the area around the main vehicle into a plurality of sub-areas according to the coordinate of the center of mass of the main vehicle, the axis of the front wheel of the main vehicle and the axis of the rear wheel of the main vehicle; determining the included angle of the far vehicle relative to the head direction of the main vehicle according to the head direction of the main vehicle and the head direction of the far vehicle; and determining the early warning radius according to the distribution of the centroid coordinates of the remote vehicles in the sub-area and the included angle of the vehicle head direction.

In one embodiment, the right front sub-region, the right side sub-region, the front sub-region, the left rear sub-region, the front sub-region and the right rear sub-region.

In an embodiment, the dividing module may be specifically configured to determine the warning radius according to a correspondence between the sub-area, the warning radius determination formula, and the vehicle head direction included angle.

In one embodiment, the corresponding relationship between the sub-area, the early warning radius determination formula and the vehicle head direction included angle is shown in table 1.

For specific limitations of the vehicle warning device, reference may be made to the above limitations of the vehicle warning method, and details are not repeated here. All or part of the modules in the vehicle early warning device can be realized by software, hardware and a combination thereof. The modules can be embedded in a hardware form or independent from a processor in the computer device, and can also be stored in a memory in the computer device in a software form, so that the processor can call and execute operations corresponding to the modules.

In an embodiment, a computer device is provided, which includes a memory and a processor, where the memory stores a computer program, and the processor, when executing the computer program, implements the steps in any of the method embodiments, and may specifically implement the following steps:

It should be clear that, in the embodiments of the present application, the process of executing the computer program by the processor is consistent with the process of executing the steps in the above method, and specific reference may be made to the description above.

In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored, and when executed by a processor, the computer program implements the steps in any of the above method embodiments, and may specifically implement the following steps:

It will be understood by those skilled in the art that all or part of the processes of the methods of the embodiments described above can be implemented by hardware instructions of a computer program, which can be stored in a non-volatile computer-readable storage medium, and when executed, can include the processes of the embodiments of the methods described above. Any reference to memory, storage, database, or other medium used in the embodiments provided herein may include non-volatile and/or volatile memory, among others. Non-volatile memory can include read-only memory (ROM), Programmable ROM (PROM), Electrically Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), or flash memory. Volatile memory can include Random Access Memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDRSDRAM), Enhanced SDRAM (ESDRAM), Synchronous Link DRAM (SLDRAM), Rambus Direct RAM (RDRAM), direct bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A vehicle warning method, comprising:

2. The method of claim 1, wherein the determining whether a closest distance point closest to the host vehicle exists on the motion trail of the vehicle to be early-warned by adopting a kinematic bicycle model according to the vehicle information of the host vehicle and the vehicle information of the vehicle to be early-warned comprises:

respectively bringing the vehicle information of the main vehicle and the vehicle to be early-warned into a discretized kinematic bicycle model to obtain a kinematic equation of the main vehicle and a kinematic equation of the vehicle to be early-warned;

determining the vehicle operation parameters corresponding to each moment according to the motion equation of the main vehicle and the motion equation of the remote vehicle;

and determining whether a closest distance point closest to the main vehicle exists on the motion trail of the vehicle to be early warned according to the vehicle operation parameters.

3. The method of claim 2, wherein the determining whether a closest distance point with a closest distance to the host vehicle exists on the motion trail of the vehicle to be pre-warned according to the vehicle operation parameters comprises:

if the vehicle operation parameters at the current moment meet at least one of preset condition sets, determining that a closest distance point with the shortest distance to the main vehicle exists on the motion trail of the vehicle to be pre-warned; the condition set comprises the correlation between the vehicle operation parameters and preset early warning radiuses;

if the vehicle operation parameter at the current moment does not meet any one of the condition sets, iteratively calculating the vehicle operation parameter at the next moment until the vehicle operation parameter meets at least one of the condition sets, or the iteration number is greater than a preset iteration number threshold.

4. The method of claim 3, wherein the vehicle operating parameters comprise: at least one of a centroid connecting line vector of the two vehicles, a centroid distance of the two vehicles, a relative motion track vector of the distant vehicle with respect to the main vehicle, a traveling speed of the distant vehicle, a traveling acceleration of the main vehicle, and a traveling acceleration of the distant vehicle.

5. The method of claim 3, wherein the set of conditions comprises at least one of;

the first condition is that: the centroid distance between the main vehicle and the vehicle to be early-warned at the current moment is smaller than the preset early-warning radius;

the second condition is that: the absolute value of the relative motion track vector of the vehicle to be pre-warned at the current moment is greater than or equal to the centroid distance of the main vehicle and the vehicle to be pre-warned at the current moment;

a third condition: the sum of the absolute values of the relative motion track vectors of the vehicles to be pre-warned at each moment is greater than or equal to the centroid distance of the main vehicle and the vehicles to be pre-warned at the current moment;

a fourth condition: the projection distance of the host vehicle at the previous moment is less than or equal to the projection distance of the host vehicle at the current moment;

6. The method of claim 4, wherein if the set of conditions includes the fourth condition, the method further comprises:

projecting the barycenter coordinate of the main vehicle on the relative motion trail vector of the vehicle to be early-warned to obtain a projection point coordinate;

and determining the projection distance according to the projection point coordinates and the barycenter coordinates of the main vehicle.

7. The method of claim 5, wherein the determining the collision time of the vehicle to be pre-warned colliding with the host vehicle according to the vehicle motion parameter comprises:

if the vehicle motion parameter meets the fourth condition or the fifth condition, determining the collision distance according to the vehicle motion parameter at the previous moment;

if the vehicle motion parameter does not meet the fourth condition and the fifth condition, determining a collision distance according to the vehicle motion parameter at the current moment;

and determining the collision time according to the collision distance, the relative running speed of the vehicle to be early-warned relative to the main vehicle at the current moment and the previous moment, the iteration times and the time interval.

8. The method of claim 7, wherein determining the collision distance from the vehicle motion parameter at a previous time comprises:

according to the formula

Determining the collision distance

Wherein, B_n-2Is the centroid coordinate of the vehicle to be pre-warned at the moment n-2, B_n-1Is the centroid coordinate of the vehicle to be pre-warned at the moment of n-1, A_n-1Barycentric coordinates of the principal car at time n-1, C_n-1Is the projected point coordinate at time n-1,

9. the method of claim 7, wherein determining the collision distance from the vehicle motion parameter at a previous time comprises:

according to the formula

Determining the collision distance

10. the method of claim 6, wherein determining the collision time based on the collision distance, the traveling speed of the host vehicle, the relative traveling speeds of the vehicle to be warned relative to the host vehicle at the current time and the previous time, the number of iterations, and the time interval comprises:

according to the formula

as the distance of the collision,

is the running speed of the main vehicle,

the driving speed of the vehicle to be pre-warned is obtained.

11. The method of claim 7, wherein the safety warning of the vehicle to be warned according to the collision time and the closest point of distance comprises:

determining the safety early warning level of the vehicle to be early warned according to a preset maximum early warning level, the collision time, the time interval, the early warning radius, a preset safety factor and the shortest relative distance; the shortest relative distance is a distance between a closest distance point and the centroid coordinates of the host vehicle.

12. The method according to claim 11, wherein the determining the safety precaution level of the vehicle to be precasted according to a preset maximum precaution level, the collision time, the time interval, the precaution radius, a preset safety factor and a shortest relative distance comprises:

according to the formula

13. The method according to claim 1, wherein the vehicle information includes at least one of a running speed, a running acceleration, a yaw angle, and a vehicle speed direction angle for characterizing a running state of the vehicle, and a centroid coordinate, a front wheel axis, a rear wheel axis, and a front wheel rotation angle for characterizing physical attribute information of the vehicle.

14. The method according to any one of claims 1 to 13, wherein the determining whether a closest distance point closest to the host vehicle exists on the motion trail of the vehicle to be pre-warned by adopting a kinematic bicycle model according to the vehicle information of the host vehicle and the vehicle information of a plurality of remote vehicles comprises:

15. The method of claim 14, wherein the sub-region comprises:

a right front sub-region, a right side sub-region, a front right sub-region, a front left sub-region, a left side sub-region, a rear left sub-region, a rear right sub-region, and a rear right sub-region.

16. The method of claim 15, wherein the determining the early warning radius corresponding to the distant car according to the distribution of the centroid coordinates of the distant car in the sub-area and the included angle of the direction of the car head comprises:

17. The method of claim 16, wherein the correspondence between the sub-region, the early warning radius determination formula, and the nose direction included angle is shown in table 1, including;

TABLE 1

Wherein the content of the first and second substances,

R_w＝R_w6＝L_f,A+L_r,B

R_w＝R_w7＝L_f,A+L_f,B

R_w＝R_w11＝L_r,A+L_f,B

R_w＝R_w12＝L_r,A+L_r,B

wherein Rw is the early warning radius, theta_refIs included angle of the headstock direction, L_f,AIs the vertical distance, L, between the coordinate of the center of mass of the main vehicle and the axis of the front wheel of the main vehicle_r,AIs the vertical distance L between the coordinate of the center of mass of the main vehicle and the axis of the rear wheel of the main vehicle_f,BIs the perpendicular distance, L, between the centroid coordinate of the remote vehicle and the axis of the front wheel of the remote vehicle_r,BIs the perpendicular distance between the barycentric coordinate of the remote vehicle and the axis of the rear wheel of the remote vehicle, W_AIs the width of the main car, W_BThe width of the faraway car; and deltal is a reserved distance.

18. A vehicle warning device, the device comprising:

19. A computer device comprising a memory and a processor, the memory storing a computer program, wherein the processor implements the steps of the method of any one of claims 1 to 17 when executing the computer program.