A method, device, equipment and storage medium for calculating collision time

Abstract

The present application discloses a collision time calculation method, device, equipment and storage medium, the method comprising: calculating the possible state of the main vehicle at a future moment based on the current state information of the main vehicle under the condition that the vehicle dynamics constraints are satisfied, the state information including contour coordinates, speed and acceleration; calculating the contour coordinates of the target vehicle at a future moment based on the current state information of the target vehicle, the target vehicle being a vehicle within a preset range around the main vehicle; judging whether the main vehicle and the target vehicle collide based on the contour coordinates of the possible state of the main vehicle at a future moment and the contour coordinates of the target vehicle at a corresponding moment; if it is judged that the main vehicle and the target vehicle collide at a future target moment, obtaining the collision time based on the future target moment of the collision, thereby improving the technical problem that the existing technology does not take into account the possible future behavior changes of the vehicle, resulting in a large error between the calculated collision time and the actual situation.

Description

Technical Field

[0001] The present application relates to the field of autonomous driving technology, and in particular to a collision time calculation method, device, equipment and storage medium. Background Art

[0002] Time-to-collision (TTC) is a commonly used indicator in vehicle driving safety assessments. The existing method for calculating collision time is to divide the distance between the two vehicles by their relative speed, and can also take into account the acceleration of the two vehicles. This calculation method can provide a relatively accurate estimate when the collision time is short. However, when the collision time is long, this calculation method only considers the current state of the vehicle and does not take into account possible future changes in the vehicle's behavior, resulting in a large error between the calculated collision time and the actual situation. Summary of the Invention

[0003] The present application provides a collision time calculation method, device, equipment and storage medium for improving the technical problem that the existing technology does not take into account the possible future behavior changes of the vehicle, resulting in a large error between the calculated collision time and the actual situation.

[0004] In view of this, the first aspect of the present application provides a collision time calculation method, comprising:

[0005] Based on the current state information of the host vehicle, the possible state of the host vehicle at a future time is calculated under the condition that the vehicle dynamics constraints are satisfied. The state information includes the profile coordinates, velocity and acceleration.

[0006] Calculating the outline coordinates of the target vehicle at a future time based on the current state information of the target vehicle, wherein the target vehicle is within a preset range around the main vehicle;

[0007] Determining whether a collision occurs between the host vehicle and the target vehicle based on the outline coordinates of the host vehicle in a possible state at a future moment and the outline coordinates of the target vehicle at a corresponding moment;

[0008] If it is determined that the host vehicle and the target vehicle collide at a future target time, a collision time is obtained according to the future target time of the collision.

[0009] Optionally, the calculation of the possible state of the host vehicle at a future moment based on the current state information of the host vehicle and under the condition that vehicle dynamics constraints are satisfied includes:

[0010] Obtaining a possible acceleration of the host vehicle at a future time that satisfies the jerk limit and acceleration limit in the vehicle dynamics constraints;

[0011] calculating a possible speed and a possible displacement of the host vehicle at a future time based on the current speed and acceleration of the host vehicle and the possible acceleration of the host vehicle at a future time, wherein the possible speed of the host vehicle at a future time satisfies a speed constraint condition in the vehicle dynamics constraint;

[0012] Calculate the possible contour coordinates of the main vehicle at a future time based on the current contour coordinates of the main vehicle and the possible displacement of the main vehicle at a future time;

[0013] The possible state of the host vehicle at the future moment is generated according to the possible acceleration, possible speed and possible contour coordinates of the host vehicle at the future moment.

[0014] Optionally, the calculating the contour coordinates of the target vehicle at a future moment according to the current state information of the target vehicle includes:

[0015] Calculating the displacement of the target vehicle at a future time based on the current speed and acceleration of the target vehicle;

[0016] The contour coordinates of the target vehicle at a future time are calculated according to the current contour coordinates of the target vehicle and the displacement of the target vehicle at a future time.

[0017] Optionally, the determining whether the host vehicle and the target vehicle collide based on the contour coordinates of the host vehicle in a possible state at a future moment and the contour coordinates of the target vehicle at a corresponding moment includes:

[0018] For each future moment, a breadth-first search method is used to search for possible states that the host vehicle can reach from all possible states at the moment before the future moment, and based on the contour coordinates of the host vehicle in the possible state at the future moment and the contour coordinates of the target vehicle at the corresponding moment, it is determined whether the vehicle contours of the host vehicle and the target vehicle intersect. If so, it is determined that the host vehicle and the target vehicle collide at the future moment; if not, it is determined that the host vehicle and the target vehicle do not collide at the future moment.

[0019] Optionally, the method further includes:

[0020] If it is determined that the host vehicle and the target vehicle collide at the future target time, the possible state of the host vehicle at the future target time is no longer searched.

[0021] Optionally, obtaining the collision time according to the future target moment of collision includes:

[0022] Calculating the ratio of the number of possible states of the host vehicle in which a collision occurs at the future target time to the total number of possible states of the host vehicle at the future target time to obtain a collision state ratio;

[0023] The minimum moment among the future target moments at which the collision state ratio is greater than a preset safety threshold is selected as the collision time.

[0024] A second aspect of the present application provides a collision time calculation device, comprising:

[0025] a first calculation unit, configured to search for possible states of the host vehicle at a future time point under the condition that vehicle dynamics constraints are satisfied based on current state information of the host vehicle, the state information including profile coordinates, velocity, and acceleration;

[0026] A second calculation unit is used to calculate the outline coordinates of the target vehicle at a future time according to the current state information of the target vehicle, wherein the target vehicle is a vehicle within a preset range around the main vehicle;

[0027] a judgment unit, configured to judge whether a collision occurs between the host vehicle and the target vehicle based on the outline coordinates of the host vehicle in a possible state at a future moment and the outline coordinates of the target vehicle at a corresponding moment;

[0028] The acquisition unit is configured to acquire a collision time according to the future target time when the collision occurs if it is determined that the host vehicle and the target vehicle collide at the future target time.

[0029] Optionally, the first computing unit is specifically configured to:

[0030] Obtaining a possible acceleration of the host vehicle at a future time that satisfies the jerk limit and acceleration limit in the vehicle dynamics constraints;

[0031] calculating a possible speed and a possible displacement of the host vehicle at a future time based on the current speed and acceleration of the host vehicle and the possible acceleration of the host vehicle at a future time, wherein the possible speed of the host vehicle at a future time satisfies a speed constraint condition in the vehicle dynamics constraint;

[0032] Calculate the possible contour coordinates of the main vehicle at a future time based on the current contour coordinates of the main vehicle and the possible displacement of the main vehicle at a future time;

[0033] The possible state of the host vehicle at the future moment is generated according to the possible acceleration, possible speed and possible contour coordinates of the host vehicle at the future moment.

[0034] A third aspect of the present application provides a collision time calculation device, the device comprising a processor and a memory;

[0035] The memory is used to store program code and transmit the program code to the processor;

[0036] The processor is configured to execute any one of the collision time calculation methods described in the first aspect according to instructions in the program code.

[0037] In a fourth aspect, the present application provides a computer-readable storage medium, which is used to store program code. When the program code is executed by a processor, the collision time calculation method described in any one of the first aspects is implemented.

[0038] It can be seen from the above technical solutions that this application has the following advantages:

[0039] The present application provides a collision time calculation method, comprising: calculating the possible state of the host vehicle at a future time based on current state information of the host vehicle while satisfying vehicle dynamics constraints, the state information including contour coordinates, speed, and acceleration; calculating the contour coordinates of a target vehicle at a future time based on the current state information of the target vehicle, the target vehicle being a vehicle within a preset range around the host vehicle; judging whether a collision occurs between the host vehicle and the target vehicle based on the contour coordinates of the possible state of the host vehicle at a future time and the contour coordinates of the target vehicle at a corresponding time; and if it is judged that a collision occurs between the host vehicle and the target vehicle at a future target time, obtaining a collision time based on the future target time at which the collision occurs.

[0040] In the present application, the possible state of the main vehicle at a future moment is estimated based on the current state information of the main vehicle, and the feasible behavior of the main vehicle at a future moment is restricted by the vehicle dynamics restriction condition, so that a more accurate possible state of the main vehicle at a future moment can be obtained, and the contour coordinates of the target vehicle at a future moment are estimated based on the current state information of the target vehicle within a preset range around the main vehicle. By judging whether the main vehicle and the target vehicle collide based on the contour coordinates of the possible state of the main vehicle at a future moment and the contour coordinates of the target vehicle at the corresponding moment, the collision time is obtained. The present application takes into account the feasible behavior of the vehicle at a future moment when calculating the collision time, which helps to improve the authenticity of the collision time calculation result, and improves the technical problem that the existing technology does not take into account the possible behavior changes of the vehicle in the future, resulting in a large error between the calculated collision time and the actual situation. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0042] Figure 1 A schematic flow chart of a collision time calculation method provided in an embodiment of the present application;

[0043] Figure 2 A schematic structural diagram of a collision time calculation device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0044] In order to help those skilled in the art better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0045] For easier understanding, see Figure 1 , an embodiment of the present application provides a collision time calculation method, comprising:

[0046] Step 101: Based on the current state information of the host vehicle, the possible state of the host vehicle at a future moment is calculated under the condition that the vehicle dynamics constraints are met. The state information includes contour coordinates, speed, and acceleration.

[0047] In the embodiment of the present application, when calculating the collision time, it is necessary to first obtain the current state information of the main vehicle and the vehicle dynamics limit. The state information includes the contour coordinates Countor, speed V and acceleration Acc of the main vehicle in the world coordinate system. In the embodiment of the present application, the contour shape of the vehicle is represented by a rectangle. Therefore, the contour coordinates of the main vehicle can be the coordinates of the four corner points of the rectangle, that is, it can be expressed as Countor = {p1, p2, p3, p4}, where p1 = (x1, y1), p2 = (x2, y2), p3 = (x3, y3), p4 = (x4, y4). Vehicle dynamics limits include speed limits (V min ,V max ), acceleration limit (A min ,A max ), jerk limit (J min ,J max ), where V min 、V max are the lower and upper limits of speed respectively; A min 、A max are the lower and upper limits of acceleration respectively; J min 、J max They are the lower and upper limits of the jerk respectively.

[0048] Obtain the possible acceleration of the main vehicle at a future moment that satisfies the jerk limit and acceleration limit conditions in the vehicle dynamics constraints; calculate the possible speed and possible displacement of the main vehicle at a future moment based on the current speed and acceleration of the main vehicle and the possible acceleration of the main vehicle in the future moment, wherein the possible speed of the main vehicle at a future moment satisfies the speed limit conditions in the vehicle dynamics constraints; calculate the possible contour coordinates of the main vehicle at a future moment based on the current contour coordinates of the main vehicle and the possible displacement of the main vehicle in the future moment; generate the possible state of the main vehicle at a future moment based on the possible acceleration, possible speed and possible contour coordinates of the main vehicle in the future moment. This application limits the feasible behavior of the main vehicle at a future moment by considering the vehicle dynamics constraints, thereby obtaining a more accurate possible state of the main vehicle at a future moment.

[0049] The main vehicle is in T i The state at the moment can be expressed as (T i ,V i ,Acc i ,Contour i ), according to the possible acceleration of the main vehicle at the next moment under the conditions of jerk limit and acceleration limit in vehicle dynamics, it is assumed that the main vehicle at the next moment T i+1 The acceleration is Acc i+1 , then the next state of the main vehicle is (T i+1 ,V i+1 ,Acc i+1 ,Contour i+1 ), where velocity and acceleration satisfy the following conditions:

[0050] V i+1 =V i +(Acc i +Acc i+1 )*dt / 2,V min <V i+1 <V max ;

[0051] A min <Acc i+1 max ;

[0052] J min <abs(Acc i+1 -Acc i ) / dt <J max ,

[0053] Where abs() is the absolute value function; dt = T i+1 -T i , is the time interval. i+1 The coordinates of each point in Contour​i The coordinates of the corresponding points in the equation are added to the coordinates of the points in the equation T. i to T i+1 The displacement is calculated, and the specific process can refer to the calculation process of the contour coordinates of the subsequent target vehicle at the future moment. The calculation process of the displacement belongs to the existing technology and will not be described in detail here.

[0054] Step 102: Calculate the outline coordinates of the target vehicle at a future time based on the current state information of the target vehicle, where the target vehicle is a vehicle within a preset range around the host vehicle.

[0055] Determine the target vehicle that interacts with the main vehicle within the preset range around the main vehicle, and obtain the current state information of the target vehicle, including the outline coordinates of the main vehicle in the world coordinate system Countor = {p o1 ,p o2 ,p o3 ,p o4}、Speed V o and acceleration Acc o , where p o1 =(x o1 ,y o1 ), p o2 =(x o2 ,y o2 ), p o3 =(x o3 ,y o3 ), p o4 =(x o4 ,y o4 ).

[0056] The displacement of the target vehicle at the future time is calculated based on the current speed and acceleration of the target vehicle at T0. i The displacement is s i =V o T i +Acc o T i 2 / 2; Calculate the contour coordinates of the target vehicle at the future time according to the current contour coordinates of the target vehicle and the displacement of the target vehicle at the future time. The target vehicle will be at the future time T i The contour coordinates are Countor={p i1 ,p i2 ,p i3 ,p i4}, where p i1 =(x o1 +s i ,y o1 +s i ), p i2 =(x o2 +si ,y o2 +s i ), p i3 =(x o3 +s i ,y o3 +s i ), p i4 =(x o4 +s i ,y o4 +s i ).

[0057] Step 103 : Determine whether a collision occurs between the host vehicle and the target vehicle based on the outline coordinates of the host vehicle in a possible state at a future moment and the outline coordinates of the target vehicle at a corresponding moment.

[0058] For each future moment, a breadth-first search method can be used to search for possible states that the host vehicle can reach from all possible states at the moment before the future moment, and based on the contour coordinates of the host vehicle in the possible state at the future moment and the contour coordinates of the target vehicle at the corresponding moment, it is determined whether the vehicle contours of the host vehicle and the target vehicle intersect. If so, it is determined that the host vehicle and the target vehicle collide at the future moment. If not, it is determined that the host vehicle and the target vehicle do not collide at the future moment.

[0059] The breadth-first search method can be used to find the future time T i , search from all T i-1 The possible states at the time are the states that can be reached, and then it is determined whether the vehicle outline of the host vehicle in this state intersects with the vehicle outline of the target vehicle at the corresponding time. The vehicle outline area of the host vehicle and the vehicle outline area of the target vehicle can be determined based on the outline coordinates of the host vehicle and the outline coordinates of the target vehicle. By comparing whether the vehicle outline area of the host vehicle and the vehicle outline area of the target vehicle intersect, it is determined whether the host vehicle and the target vehicle have collided. If it is determined that the vehicle outline of the host vehicle and the vehicle outline of the target vehicle intersect at a certain future time T i If they intersect, it is determined that the host vehicle and the target vehicle are at the future time T i A collision occurs, at the future time T i That is, the future target time when the main vehicle and the target vehicle collide; if the vehicle profile of the main vehicle and the vehicle profile of the target vehicle are judged to be in the future time T i If they do not intersect, it is determined that the host vehicle and the target vehicle are at the future time T i No collision occurs, that is, the main vehicle will be at the next time T i In a safe state.

[0060] Furthermore, if it is determined that the host vehicle and the target vehicle are at the future target time T i If a collision occurs, the host vehicle can no longer bei The future moment (T i+1 ,T i+2 ...) is searched, it is only necessary to calculate the collision state ratio of the future target time T i All future states of the state are counted into the unsafe part, that is, the future target time T i All future states of the state are considered as states where collision will occur.

[0061] Step 104: If it is determined that the host vehicle and the target vehicle collide at the future target time, a collision time is obtained according to the future target time of the collision.

[0062] If it is determined that the host vehicle and the target vehicle will be at the target time T in the future i If a collision occurs, calculate the host vehicle's target time in the future T i The number of possible states n of collision and the target time T of the main vehicle in the future i The ratio n / m of the total number m of possible states is used to obtain the collision state ratio P col (T i )=n / m, that is, the collision state ratio P col (T i ) is the future time T i The number of states in which the main vehicle collides is related to the time T i The ratio of the total number of states.

[0063] When it is determined that the host vehicle and the target vehicle will collide at multiple future moments, multiple collision state ratios are calculated accordingly, and the collision state ratio greater than the preset safety threshold C is selected. thres The minimum time among the future target times is taken as the collision time, that is, the first time greater than the preset safety threshold C is selected. thres The time corresponding to the collision state ratio is taken as the collision time. Assume that it is judged that the main vehicle and the target vehicle will be at the future time T i 、T i+1 、T i+2 If a collision occurs, the corresponding calculated collision state ratio includes P col (T i ), P col (T i+1 ), P col (T i+2 ); if P col (T i ), P col (T i+1 ), P col (T i+2 ) are greater than the preset safety threshold C thres , then from the future time T i、T i+1 、T i+2 The smallest moment is selected as the collision time, that is, TTC = T i If P col (T i ) <C thres , P col (T i+1 )>C thres , P col (T i+2 )>C thres , then from the future time T i+1 、T i+2 The smallest moment is selected as the collision time, that is, TTC = T i+1 When calculating the collision time in the embodiment of the present application, the feasible behavior of the vehicle at a future moment is taken into account, which can effectively avoid the problem of large errors in the existing technology that calculates the collision time based only on the current state of the vehicle.

[0064] The preset safety threshold C in the embodiment of the present application thres is the preset redundant safety limit, which satisfies 0≤C thres ≤1. You can adjust the preset safety threshold C thres The size of is used to obtain the collision time of the main vehicle under different safety levels, thereby obtaining the safety status of the main vehicle under different safety levels.

[0065] For complex road conditions, there may be multiple target vehicles interacting with the host vehicle. In this case, the contour coordinates of all target vehicles at future moments can be generated to obtain the future trajectories of the target vehicles for collision detection at future moments.

[0066] In an embodiment of the present application, the possible state of the main vehicle at a future moment is estimated based on the current state information of the main vehicle, and the feasible behavior of the main vehicle at a future moment is restricted by the vehicle dynamics restriction condition, so that a more accurate possible state of the main vehicle at a future moment can be obtained, and the contour coordinates of the target vehicle at a future moment are estimated based on the current state information of the target vehicle within a preset range around the main vehicle. By judging whether the main vehicle and the target vehicle collide based on the contour coordinates of the possible state of the main vehicle at a future moment and the contour coordinates of the target vehicle at a corresponding moment, the collision time is obtained. The present application takes into account the feasible behavior of the vehicle at a future moment when calculating the collision time, which helps to improve the authenticity of the collision time calculation result, and improves the technical problem that the prior art does not take into account the possible future behavior changes of the vehicle, resulting in a large error between the calculated collision time and the actual situation.

[0067] The above is an embodiment of a collision time calculation method provided by the present application, and the following is an embodiment of a collision time calculation device provided by the present application.

[0068] Please refer to Figure 2 , an embodiment of the present application provides a collision time calculation device, comprising:

[0069] A first calculation unit is configured to search for possible states of the host vehicle at a future time based on current state information of the host vehicle, while satisfying vehicle dynamics constraints, the state information including profile coordinates, velocity, and acceleration;

[0070] The second calculation unit is used to calculate the outline coordinates of the target vehicle at a future time according to the current state information of the target vehicle, and the target vehicle is a vehicle within a preset range around the main vehicle;

[0071] A judgment unit, configured to judge whether a collision occurs between the host vehicle and the target vehicle based on the contour coordinates of the host vehicle in a possible state at a future moment and the contour coordinates of the target vehicle at a corresponding moment;

[0072] The acquisition unit is used to acquire the collision time according to the future target time when it is determined that the host vehicle and the target vehicle will collide at the future target time.

[0073] As a further improvement, the first computing unit is specifically configured to:

[0074] Obtaining a possible acceleration of the host vehicle at a future time that satisfies the jerk limit and acceleration limit in the vehicle dynamics constraints;

[0075] Calculating a possible speed and possible displacement of the host vehicle at a future time based on the current speed and acceleration of the host vehicle and the possible acceleration of the host vehicle at a future time, wherein the possible speed of the host vehicle at a future time satisfies a speed constraint condition in the vehicle dynamics constraint;

[0076] Calculate the possible contour coordinates of the main vehicle at a future time based on the current contour coordinates of the main vehicle and the possible displacement of the main vehicle at a future time;

[0077] The possible state of the host vehicle at the future moment is generated according to the possible acceleration, possible speed and possible contour coordinates of the host vehicle at the future moment.

[0078] As a further improvement, the second computing unit is specifically configured to:

[0079] Calculate the displacement of the target vehicle at a future moment based on the current speed and acceleration of the target vehicle;

[0080] The contour coordinates of the target vehicle at a future time are calculated based on the current contour coordinates of the target vehicle and the displacement of the target vehicle at a future time.

[0081] In an embodiment of the present application, the possible state of the main vehicle at a future moment is estimated based on the current state information of the main vehicle, and the feasible behavior of the main vehicle at a future moment is restricted by the vehicle dynamics restriction condition, so that a more accurate possible state of the main vehicle at a future moment can be obtained, and the contour coordinates of the target vehicle at a future moment are estimated based on the current state information of the target vehicle within a preset range around the main vehicle. By judging whether the main vehicle and the target vehicle collide based on the contour coordinates of the possible state of the main vehicle at a future moment and the contour coordinates of the target vehicle at a corresponding moment, the collision time is obtained. The present application takes into account the feasible behavior of the vehicle at a future moment when calculating the collision time, which helps to improve the authenticity of the collision time calculation result, and improves the technical problem that the prior art does not take into account the possible future behavior changes of the vehicle, resulting in a large error between the calculated collision time and the actual situation.

[0082] The embodiment of the present application further provides a collision time calculation device, the device including a processor and a memory;

[0083] The memory is used to store program codes and transmit the program codes to the processor;

[0084] The processor is configured to execute the collision time calculation method in the aforementioned method embodiment according to instructions in the program code.

[0085] An embodiment of the present application further provides a computer-readable storage medium, which is used to store program code. When the program code is executed by a processor, the collision time calculation method in the aforementioned method embodiment is implemented.

[0086] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0087] The terms "first", "second", "third", "fourth", etc. (if any) in the specification of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can, for example, be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0088] It should be understood that in this application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0089] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0090] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0091] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0092] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for executing all or part of the steps of the method described in each embodiment of the present application through a computer device (which can be a personal computer, server, or network device, etc.). The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (English full name: Read-Only Memory, English abbreviation: ROM), random access memory (English full name: Random Access Memory, English abbreviation: RAM), disk or optical disk and other media that can store program code.

[0093] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A collision time calculation method, characterized in that: include: Based on the current state information of the host vehicle, the possible state of the host vehicle at a future time is calculated under the condition that the vehicle dynamics constraints are satisfied. The state information includes the profile coordinates, velocity and acceleration. Calculating the outline coordinates of the target vehicle at a future time based on the current state information of the target vehicle, wherein the target vehicle is within a preset range around the main vehicle; Determining whether a collision occurs between the host vehicle and the target vehicle based on the outline coordinates of the host vehicle in a possible state at a future moment and the outline coordinates of the target vehicle at a corresponding moment; If it is determined that the host vehicle and the target vehicle collide at a future target time, obtaining a collision time according to the future target time of the collision; The obtaining of the collision time according to the future target moment of the collision comprises: Calculating the ratio of the number of possible states of the host vehicle in which a collision occurs at the future target time to the total number of possible states of the host vehicle at the future target time to obtain a collision state ratio; The minimum moment among the future target moments at which the collision state ratio is greater than a preset safety threshold is selected as the collision time.

2. The collision time calculation method according to claim 1, characterized in that: The calculation of the possible state of the host vehicle at a future time based on the current state information of the host vehicle and under the condition of satisfying vehicle dynamics constraints includes: Obtaining a possible acceleration of the host vehicle at a future time that satisfies the jerk limit and acceleration limit in the vehicle dynamics constraints; calculating a possible speed and a possible displacement of the host vehicle at a future time based on the current speed and acceleration of the host vehicle and the possible acceleration of the host vehicle at a future time, wherein the possible speed of the host vehicle at a future time satisfies a speed constraint condition in the vehicle dynamics constraint; Calculate the possible contour coordinates of the main vehicle at a future time based on the current contour coordinates of the main vehicle and the possible displacement of the main vehicle at a future time; The possible state of the host vehicle at the future moment is generated according to the possible acceleration, possible speed and possible contour coordinates of the host vehicle at the future moment.

3. The collision time calculation method according to claim 1, characterized in that: The step of calculating the contour coordinates of the target vehicle at a future time based on the current state information of the target vehicle includes: Calculating the displacement of the target vehicle at a future time based on the current speed and acceleration of the target vehicle; The contour coordinates of the target vehicle at a future time are calculated according to the current contour coordinates of the target vehicle and the displacement of the target vehicle at a future time.

4. The collision time calculation method according to claim 1, characterized in that: The determining whether the host vehicle and the target vehicle collide based on the outline coordinates of the host vehicle in a possible state at a future moment and the outline coordinates of the target vehicle at a corresponding moment includes: For each future moment, a breadth-first search method is used to search for possible states that the host vehicle can reach from all possible states at the moment before the future moment, and based on the contour coordinates of the host vehicle in the possible state at the future moment and the contour coordinates of the target vehicle at the corresponding moment, it is determined whether the vehicle contours of the host vehicle and the target vehicle intersect. If so, it is determined that the host vehicle and the target vehicle collide at the future moment; if not, it is determined that the host vehicle and the target vehicle do not collide at the future moment.

5. The collision time calculation method according to claim 4, characterized in that: The method further comprises: If it is determined that the host vehicle and the target vehicle collide at the future target time, the possible state of the host vehicle at the future target time is no longer searched.

6. A collision time calculation device, characterized in that: include: a first calculation unit, configured to search for possible states of the host vehicle at a future time point under the condition that vehicle dynamics constraints are satisfied based on current state information of the host vehicle, the state information including profile coordinates, velocity, and acceleration; A second calculation unit is used to calculate the outline coordinates of the target vehicle at a future time according to the current state information of the target vehicle, wherein the target vehicle is a vehicle within a preset range around the main vehicle; a judgment unit, configured to judge whether a collision occurs between the host vehicle and the target vehicle based on the outline coordinates of the host vehicle in a possible state at a future moment and the outline coordinates of the target vehicle at a corresponding moment; an acquiring unit, configured to acquire a collision time according to the future target time of the collision if it is determined that the host vehicle and the target vehicle collide at the future target time; The obtaining of the collision time according to the future target moment of the collision comprises: Calculating the ratio of the number of possible states of the host vehicle in which a collision occurs at the future target time to the total number of possible states of the host vehicle at the future target time to obtain a collision state ratio; The minimum moment among the future target moments at which the collision state ratio is greater than a preset safety threshold is selected as the collision time.

7. The collision time calculation device according to claim 6, characterized in that: The first computing unit is specifically configured to: Obtaining a possible acceleration of the host vehicle at a future time that satisfies the jerk limit and acceleration limit in the vehicle dynamics constraints; calculating a possible speed and a possible displacement of the host vehicle at a future time based on the current speed and acceleration of the host vehicle and the possible acceleration of the host vehicle at a future time, wherein the possible speed of the host vehicle at a future time satisfies a speed constraint condition in the vehicle dynamics constraint; Calculate the possible contour coordinates of the main vehicle at a future time based on the current contour coordinates of the main vehicle and the possible displacement of the main vehicle at a future time; The possible state of the host vehicle at the future moment is generated according to the possible acceleration, possible speed and possible contour coordinates of the host vehicle at the future moment.

8. A collision time calculation device, characterized in that: The device includes a processor and a memory; The memory is used to store program code and transmit the program code to the processor; The processor is configured to execute the collision time calculation method according to any one of claims 1 to 5 according to instructions in the program code.

9. A computer-readable storage medium, characterized in that The computer-readable storage medium is used to store program codes, and when the program codes are executed by a processor, the collision time calculation method according to any one of claims 1 to 5 is implemented.

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