CN109664882B

CN109664882B - Method and system for avoiding secondary collision of road vehicles and electronic equipment

Info

Publication number: CN109664882B
Application number: CN201910017307.5A
Authority: CN
Inventors: 谢兆夫
Original assignee: Guangzhou Xiaopeng Motors Technology Co Ltd
Current assignee: Guangzhou Xiaopeng Motors Technology Co Ltd
Priority date: 2019-01-08
Filing date: 2019-01-08
Publication date: 2020-10-16
Anticipated expiration: 2039-01-08
Also published as: CN109664882A

Abstract

The embodiment of the invention relates to a method and a system for avoiding secondary collision of a road vehicle and electronic equipment. The method comprises the following steps: determining whether a rear collision risk that the vehicle is rear-ended by the rear vehicle and a front collision risk that the vehicle collides with the front obstacle exist or not based on the characteristic parameters of the rear vehicle and the front obstacle detected by the environment detection component; in response to the presence of the rear collision risk and the front collision risk, calculating a collision location at which the rear vehicle will have a rear-end collision and a velocity at the collision location; and determining a braking strategy to be executed by the vehicle based on the calculated collision location and speed. According to the embodiment of the invention, different braking strategies are determined according to different conditions when the vehicle has secondary collision risks, so that the vehicle can shorten the driving distance after collision to avoid the overlarge displacement of the collided vehicle, and the driving safety of the vehicle is improved by combining other warning precautionary measures.

Description

Method and system for avoiding secondary collision of road vehicles and electronic equipment

Technical Field

The present invention generally relates to the field of vehicle control, and more particularly to a method, a system and an electronic device for avoiding a secondary collision of a road vehicle.

Background

The number of road vehicles is increasing nowadays, and safety aids in the driving of vehicles are also becoming more and more important. In an emergency driving situation in which the traffic situation changes very rapidly in road traffic, the driver is usually unresponsive and may therefore make an error or overstimulation. For example, in the case of an obstacle suddenly appearing in the front or a sudden change in the state of a running road surface, and a rear vehicle of the vehicle is about to rear-end, a secondary traffic accident occurs because the vehicle speed increases due to a collision due to an excessive rear vehicle collision speed. In an emergency situation, it is often difficult for the driver to quickly react properly to avoid a secondary collision.

Disclosure of Invention

In view of the above problems, embodiments of the present invention provide a method, a system, an electronic device, and a computer-readable storage medium for avoiding a secondary collision of a road vehicle, which effectively assist a driver in avoiding the occurrence of the secondary collision.

In a first aspect of the invention, a method of avoiding a secondary collision of a road vehicle is provided. The method comprises the following steps: determining whether there is a rear collision risk of the vehicle being rear-ended by a rear vehicle; predicting whether there is a front collision risk of the vehicle colliding with a front obstacle in response to the presence of the rear collision risk; in response to the presence of a front collision risk, calculating a collision location at which the rear vehicle is expected to rear-end collide and a velocity at the collision location; and determining a braking strategy to be executed by the vehicle based on the calculated collision location and speed.

In certain embodiments, the method further comprises: and controlling the vehicle to send out a reminding signal to a driver of the vehicle in response to the existence of the rear collision risk.

In some embodiments, determining whether a rear collision risk exists includes: calculating the collision time of the rear vehicle and the vehicle based on the characteristic parameters of the rear vehicle acquired by the vehicle detection device, wherein the collision time represents the current time period of the rear vehicle in which the expected rear-end collision occurs; and determining that there is a risk of a rear collision in response to the time-to-collision being less than the first threshold.

In certain embodiments, predicting whether a front impact risk exists includes: predicting a position trajectory of a preceding obstacle based on a characteristic parameter of the preceding obstacle acquired by a vehicle detection device; judging whether the position track is overlapped with a track of the vehicle after the expected rear-end collision; and determining that a front impact risk exists in response to the position trajectory overlapping with a trajectory of the vehicle after the anticipated rear-end impact.

In certain embodiments, at least one of the following is satisfied, and no braking strategy is implemented: the current speed of the vehicle is greater than a first vehicle speed threshold; the current vehicle speed of the vehicle is less than a second vehicle speed threshold; eliminating rear collision risk or front collision risk; and detecting an active operation of the vehicle by a driver of the vehicle.

In some embodiments, determining the braking strategy to be performed by the vehicle comprises: calculating a collision reference distance of the vehicle from the front obstacle at the time of an expected rear-end collision based on the characteristic parameters of the front obstacle and the collision position acquired by the vehicle detection device; calculating, based on the speed of the rear vehicle at the collision position, a braking distance required for the vehicle to perform a maximum deceleration that the vehicle can perform to bring the vehicle close to a stop when the vehicle performs the expected rear-end collision; and determining a braking strategy according to the relation between the collision reference distance and the braking distance.

In some embodiments, determining the braking strategy based on the relationship of the collision reference distance to the braking distance comprises: in response to the difference between the collision reference distance and the braking distance being greater than or equal to a second threshold value, determining a braking strategy for controlling the vehicle to perform braking at a braking force dependent on the braking distance when a rear-end collision occurs; and determining the braking strategy to provide braking force to the vehicle before the rear-end collision occurs in response to the difference between the collision reference distance and the braking distance being less than a second threshold value.

In some embodiments, determining the braking strategy to provide braking force to the vehicle before the rear-end collision includes: calculating a collision reference distance and a braking distance in a limit situation for the limit situation in which the maximum braking force is provided to the vehicle before the rear-end collision occurs; and in response to the difference between the collision reference distance and the braking distance in the limit situation being smaller than a second threshold value, determining the braking strategy to control the vehicle to give out a visual and/or audible warning signal for the front obstacle, and immediately controlling the vehicle to perform braking with a braking force corresponding to the maximum deceleration.

In some embodiments, determining the braking strategy of the vehicle further comprises: and determining the braking strategy to immediately control the vehicle to perform braking with the maximum braking force in response to the difference between the collision reference distance and the braking distance in the limit situation being greater than or equal to a second threshold value.

In a second aspect of the present invention, an in-vehicle system for avoiding a secondary collision of a road vehicle is provided. The system comprises: an environment detection component for detecting characteristic parameters of a vehicle behind the vehicle and a front obstacle; the electronic control unit is used for determining whether a rear collision risk that the vehicle is rear-ended by a rear vehicle and a front collision risk that the vehicle collides with a front obstacle exist or not based on the characteristic parameters detected by the environment detection assembly; in response to the presence of the rear collision risk and the front collision risk, calculating a collision location at which the rear vehicle will have a rear-end collision and a velocity at the collision location; and determining a braking strategy to be executed by the vehicle based on the calculated collision location and speed; and a braking system that performs vehicle braking according to the determined braking strategy.

In some embodiments, the system further comprises an information alert system that outputs a visual, audible, and/or tactile alert.

In some embodiments, determining a braking strategy to be implemented by the vehicle based on the location and speed of the collision includes: calculating a collision reference distance of the vehicle from the front obstacle at the time of a rear-end collision based on the characteristic parameters of the front obstacle and the collision position acquired by the vehicle detection device; calculating, based on the speed of the rear vehicle at the collision position, a braking distance required for the vehicle to perform a maximum deceleration that the vehicle can perform to bring the vehicle close to a stop when the vehicle performs the expected rear-end collision; and determining a braking strategy according to the relation between the collision reference distance and the braking distance.

In a third aspect of the present invention, there is provided an electronic apparatus comprising: a processor; and a memory storing instructions which, when executed by the processor, cause the apparatus to perform the method as described in accordance with the first aspect of the invention.

In a fourth aspect of the invention, there is provided a computer readable storage medium storing machine readable instructions which, when executed by a machine, cause the machine to perform the method described in accordance with the first aspect of the invention.

According to the scheme for avoiding the secondary collision of the road vehicle, provided by the embodiment of the invention, different braking strategies are determined according to different conditions when the vehicle has the risk of the secondary collision, so that the vehicle can shorten the driving distance after the collision to avoid the overlarge displacement of the collided vehicle, and the driving safety of the vehicle is improved by combining other warning precautionary measures.

Drawings

FIG. 1 shows a schematic diagram of one scenario in which an embodiment according to the present invention is applied;

FIG. 2 shows a schematic block diagram of a system for avoiding a secondary collision of a road vehicle according to an embodiment of the present invention;

FIG. 3 shows a flow chart of a method of avoiding a secondary collision of a road vehicle according to one embodiment of the invention;

FIG. 4 shows a flow chart of a braking strategy decision process according to an embodiment of the invention; and

FIG. 5 illustrates a block diagram of an electronic device suitable for implementing embodiments of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments and the accompanying drawings. Those skilled in the art will appreciate that the present invention is not limited to the drawings and the following examples.

As used herein, the term "include" and its various variants are to be understood as open-ended terms, which mean "including, but not limited to. The term "based on" may be understood as "based at least in part on". The term "one embodiment" may be understood as "at least one embodiment". The term "another embodiment" may be understood as "at least one other embodiment".

As described above, the current vehicles lack consideration and configuration for effectively avoiding secondary collision, and the embodiments of the present invention are directed to providing solutions in some application scenarios to improve the driving safety of the vehicle. Embodiments of the present invention are further described below with reference to the accompanying drawings.

FIG. 1 shows a schematic diagram of a scenario 100 in which embodiments of the present invention are applied. As shown, the vehicle 110 in question travels on a road, and its rear vehicle (i.e., rear vehicle) 120 comes along the same lane, there may be a risk of rear-end collision (referred to as rear collision risk), while an obstacle 130 such as a pedestrian road user (VRU) or other vehicles appears in front of the vehicle 110, with a potential risk of collision (referred to as front collision risk). At this time, even if the vehicle 110 itself has a low speed, the rear-end collision of the rear vehicle 120 may increase the speed of the vehicle 110, which may cause a collision with the front obstacle 130, that is, a secondary collision, and a secondary traffic accident may occur.

Although the scenario 100 is shown to include a scenario in which the vehicle 110 is crossing a vehicle or pedestrian ahead of a way at a traffic intersection, it should be understood that embodiments of the present invention are also applicable to other scenarios, such as when the vehicle ahead is suddenly stopped on an expressway.

In accordance with an embodiment of the present invention, under the scenario 100 described above, the vehicle 110 will comprehensively analyze the rear collision risk and the front collision risk, and provide corresponding braking strategies and other precautionary measures to avoid the occurrence of a secondary collision. Fig. 2 shows a schematic block diagram of a system 200 for avoiding a secondary collision of a road vehicle according to an embodiment of the invention, which system 200 may be part of the vehicle 110 in question.

As shown, the system 200 includes an Electronic Control Unit (ECU) 210 as a main control unit, an environment detection component 220, various driving performance detection sensors 230 and 260 (referred to as driving performance detection components), a brake system 270, and an information reminding system 280. Among them, the environment sensor 220 may include a lateral rear sensor such as a radar or a camera, a front millimeter wave radar, a front camera, and the like, and the driving performance detection sensor may include a wheel speed sensor 230, a steering wheel angle sensor 240, a wheel cylinder pressure sensor 250, an accelerator pedal position sensor 260, and the like.

The lateral rear sensor is used for detecting characteristic parameters of other vehicles 120 in the area behind the vehicle, such as distance, speed, profile and the like, and providing the characteristic parameters to the ECU210 so that the ECU210 can make decisions. The front millimeter wave radar and the camera are used for detecting characteristic parameters such as the distance, the speed and the outline of the obstacle 130 in front of the vehicle 110, and particularly for pedestrian recognition, data detected by the front camera are output to the ECU210 for data fusion judgment.

The wheel speed sensor 230 detects the current running speed of the vehicle 110; the steering wheel angle sensor 240 detects a torque or an angle of rotation applied to the steering wheel end to determine a steering operation of the vehicle 110; the wheel cylinder pressure sensor 250 detects the brake pressure applied by the brake system; an accelerator pedal position sensor 260 monitors the position of the accelerator pedal. These sensors all provide information for the decision making of the ECU 210.

The ECU210 receives information sent from various sensors, makes braking decisions to avoid a secondary collision and other precautionary measures, and controls the operation of the braking system 270 and the information providing system 280. The brake system 270 brakes the vehicle by decelerating by controlling the wheel cylinder pressure according to the instruction of the ECU 210. The information alert system 280 may include a display screen, a vehicle meter, a vehicle light, a whistle device, etc. that outputs visual, audible, tactile, etc. alerts for the driver or other interested party.

It is to be understood that the system 100 described above is merely illustrative and that other components of the system 100 are not specifically shown and described in order to facilitate describing embodiments of the present invention in order to avoid unnecessarily obscuring aspects of the embodiments of the present invention.

A scheme for avoiding a secondary collision of a road vehicle according to an embodiment of the present invention is described below in conjunction with scenario 100 in fig. 1. Fig. 3 shows a flow chart of a method 300 of avoiding a secondary collision of a road vehicle according to an embodiment of the invention.

At 310, it is determined whether there is a risk of a rear collision in which the vehicle is rear-ended by a rear vehicle. In one embodiment, the rear area of vehicle 110 is detected by environmental sensor 220. When the rear vehicle 120 is found, a Time To Collision (TTC) to be collided is calculated based on the detected characteristic parameters of the rear vehicle 120, such as the distance of the rear vehicle 120 from the vehicle 110, the speed of the rear vehicle 120, and acceleration information. TTC represents the current time period for which the vehicle will collide.

Once the TTC is less than a certain threshold, it can be considered that a rear-end collision is imminent, i.e., there is a risk of a rear collision. At this point, an early warning may be triggered immediately, giving an audible or visual warning signal to the driver of vehicle 110.

At 320, in response to the presence of a rear collision risk, it is predicted whether a front collision risk exists for the vehicle to collide with a front obstacle. In one embodiment, the front obstacle 130 is detected and identified by an environmental sensor 220 such as a front millimeter wave radar or a front camera, and the characteristic parameters of the detected front obstacle 130 are fed back to the ECU 210. These characteristic parameters include the distance of the front obstacle 130 from the vehicle 110, the speed, acceleration, profile, and the like of the front obstacle 130.

Based on the characteristic parameters of the front obstacle 130, the ECU210 predicts whether the trajectory of the front obstacle 130 will coincide with the travel trajectory of the vehicle 110 after a rear-end collision. If the tracks coincide, the potential collision in front is judged, namely the front collision risk exists.

It should be noted that, according to an embodiment of the present invention, considering that the automatic emergency braking system cannot take into account the responsibility division problem that the vehicle runs at a low speed and the vehicle brakes at a higher speed to cause great damage to the vehicle behind and the rear-end collision, the method 300 may be effectively performed only when the vehicle 110 is at a low speed (for example, less than 5 km/h) or the vehicle is at a standstill, that is, braking is performed according to a subsequently determined braking strategy to avoid a secondary collision. In the event that the vehicle speed is high, operation may be performed in accordance with the automatic emergency braking system configuration of vehicle 110. Therefore, the ECU 110 may decide whether to activate the braking strategy according to the embodiment of the present invention through the vehicle running speed information detected by the wheel speed sensor 230. In order to prevent the driver from being confused, the information alert system 280 alerts the driver that the secondary collision avoidance function is activated by a sound or a blinking screen, for example, when the function is activated.

Next, in response to the presence of a front collision risk, a collision location at which the rear vehicle will have a rear-end collision and a speed at the collision location are calculated at 330 for the ECU210 to determine a braking strategy for the vehicle.

In one embodiment, the environment sensor 220 continuously detects the driving characteristic parameters of the rear vehicle 120 in real time, the ECU210 predicts the future state quantity of the rear vehicle 120 based on kalman filtering according to the driving characteristic parameters of the rear vehicle 120, and calculates the predicted collision position Pc and the speed v at which the rear vehicle 120 reaches the collision position Pc₀。

Then, at 340, a braking strategy for the vehicle is determined based on the calculated collision location at which the rear vehicle will have a rear-end collision and the velocity at the collision location. In one embodiment, the braking strategy may include the point in time at which the vehicle 110 is required to brake and the amount of deceleration or braking force required during braking.

In one embodiment, the environmental sensor 220 continuously detects the characteristic parameters of the front obstacle 130 in real time, and the ECU210 predicts the future state quantity of the front obstacle 130 based on kalman filtering from the characteristic parameters of the rear front obstacle 130. The ECU210 calculates the distance of the vehicle 110 from the front obstacle 130 at the collision position Pc based on the predicted collision position Pc and the future trajectory of the front obstacle 130Distance S₀(referred to as collision reference distance).

According to the prediction of the vehicle speed v at the time when the rear vehicle 120 reaches the collision point Pc as described above₀The velocity v after collision can be obtained by applying the momentum theorem in the classical theoretical mechanics_t. Assume mass m of vehicle 110₁Mass m of the rear vehicle 120₂Both are rigid bodies and can approximate the mass of the vehicle 110 to predict the mass of the rear vehicle 120, i.e., m₁≈m₂. Obtaining v according to the following formula (1)_t：

m₂v₀＝(m₁+m₂)v_t(1)

Further, according to the maximum deceleration a which can be currently performed by the brake system of the vehicle on the conventional paved road₀The distance S required for braking the vehicle 110 and the rear vehicle 120 to a vehicle speed close to 0 can be calculated from the following equation (2)₁(referred to as braking distance):

2a₀S₁＝v_t ²(2)

the ECU210 calculates the collision reference distance S based on the calculated collision reference distance S₀Distance S from the brake₁May determine different braking strategies for vehicle 110. FIG. 4 shows a flow diagram of a braking strategy decision process 400 according to an embodiment of the invention.

As shown, the process 400 begins at 401, where a collision reference distance S is calculated at 403₀Distance S from the brake₁The procedure is as described above. Then, at 405, S is compared₁+S_sAnd S₀Wherein it is assumed that the safe braking reserve safe distance of the vehicle 110 is S_sGenerally, 1 meter can be taken as a reference.

When judged at 405S₁+S_s≤S₀When this occurs, the ECU210 determines that the present system can allow the vehicle 110 to avoid a secondary collision of the vehicle 110 with the front obstacle 130 after the collision occurs, and therefore the process 400 proceeds to 407, and a braking request may be generated. In this case, the braking request does not need to be sent immediately, and may be sent between the current time and the occurrence of the rear-end collision, or may be sent when the rear-end collision occurs,to control the actuation of the braking system 270. In one embodiment, the braking of the braking system 270 is not advanced, but rather is after a rear-end collision, in view of driving safety and impact on the rear vehicle 120. In this case, the ECU210 can calculate the braking distance S at that time₁To determine how much deceleration to brake vehicle 110 to a stop to take overall consideration of the comfort of the driver's ride. Accordingly, the brake system 270 converts the deceleration instructed by the ECU210 into a corresponding braking force upon receiving a braking request, and changes the magnitude of the wheel cylinder pressure value to perform vehicle braking.

When judged at 405S₁+S_s>S₀When the ECU210 determines that the current system cannot allow the vehicle 110 to avoid a secondary collision between the vehicle 110 and the front obstacle 130 after the collision occurs, the vehicle 110 needs to be braked in advance. In one embodiment of the present invention, the ECU210 provides the maximum braking force F that is the upper limit value of the braking force that can be provided by the braking system of the vehicle 110_bmaxTo further determine the braking strategy.

To simplify the operation process, the following assumptions are made. Since process 400 occurs when vehicle 110 is traveling at a low speed or is stationary, vehicle 110 is easily braked to a standstill, assuming for simplicity that vehicle 110 is already stationary and that vehicle 110 is now holding the brake system via an Electronic Stability Control (ESC) system, providing braking force F_bmax. The velocity v of the vehicle 110 after the rear-end collision in this case can be obtained from the following equation (3) according to the impulse law of classical mechanics_t：

m₂v₀＝(m₁+m₂)v_t+F_bmax*t (3)

Further, the braking distance S in this case can be calculated from the above equation (2)₁Thereby obtaining a collision reference distance S₀Distance S from the brake₁In the context of (a) or (b),

then, S is further judged at 411₁+S_sAnd S₀The relationship (2) of (c). If even at the time of providing the braking force F_bmaxThe front collision still cannot be avoided on the basis,namely S₁+S_s>S₀This is still true, where ECU210 controls to alert the leading vehicle or pedestrian to the attention of the vehicle by whistling or flashing the headlights at 413 and still issues a request to brake system 270 at 415, controlling vehicle 110 to skip execution in accordance with the deceleration level of the maximum speed drop that vehicle 110 can execute, with process 400 then ending at 417.

If it is determined at 411 that braking force F is being provided_bmaxCan avoid front collision on the basis of (S)₁+S_s≤S₀If true, jump to 407 generates a braking request. At this time, the brake system is pressurized to provide a braking force F_bmax. The braking request needs to be sent immediately, in other words, the time point when the vehicle 110 needs to brake is the current time before the rear-end collision occurs.

After the ECU210 determines the braking strategy, the ECU210 sends a braking request according to the braking strategy, and braking is achieved by varying the magnitude of the wheel cylinder pressure value by a braking system 270 such as an Electronic Stability Program (ESP) system.

In one embodiment, it is also considered whether the driver of vehicle 110 is actively involved in the hope of taking over vehicle 110. If the driver wishes to intervene actively, the braking strategy process provided by embodiments of the present invention may be exited. The ECU210 can determine whether the driver is actively involved in the intention of desiring to take over the vehicle by feedback of the actuator information transmitted from the steering wheel angle sensor 240, the wheel cylinder pressure sensor 250, or the accelerator pedal position sensor 260.

Further, in one embodiment of the present invention, the above-described secondary collision avoidance procedure may be exited if certain end conditions are met. The end condition may include a condition of the vehicle 110 or a state change of the front obstacle 130. The conditions of the vehicle 110 include whether the vehicle 110 decelerates to a standstill after a collision, and if the vehicle is stationary, the electronic parking system may be requested to take over the vehicle. The state change of the front obstacle 130 includes a change in the movement locus of the front object or the pedestrian, and it is found by calculation that there is no longer a degree of coincidence with the travel locus of the vehicle 110, that is, there is no longer a risk of collision with the front obstacle 130. And if the ending condition is not met, continuing to send a braking request according to the braking strategy, otherwise, exiting the process of avoiding secondary collision.

As can be seen from the above description of the embodiment of the present invention, when it is found that there is a risk of colliding other objects in front under the condition of triggering the rear collision early warning, the embodiment of the present invention performs calculation and logic decision by using the ECU, and sends different braking requests to the braking system according to the braking strategy, so as to shorten the displacement of the vehicle after collision, thereby achieving the purpose of avoiding secondary collision. Meanwhile, when the collision of the front of the vehicle cannot be avoided, the driver, the front and rear vehicles and the pedestrians are reminded in a mode of whistling or flickering headlights.

Fig. 5 illustrates a block diagram of an electronic device 500 suitable for implementing embodiments of the present invention. The device 500 may be used to implement the electronic control unit 210 or a portion thereof. As shown, the device 500 includes a processor 510. Processor 510 controls the operation and functions of device 500. For example, in some embodiments, processor 510 may perform various operations by way of instructions 530 stored in memory 520 coupled thereto. The memory 520 may be of any suitable type suitable to the local technical environment and may be implemented using any suitable data storage technology, including but not limited to semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems. Although only one memory unit is shown in FIG. 5, there may be multiple physically distinct memory units within device 500.

The processor 510 may be of any suitable type suitable to the local technical environment, and may include, but is not limited to, one or more of general purpose computers, special purpose computers, microcontrollers, digital signal controllers (DSPs), and controller-based multi-core controller architectures. The device 500 may also include multiple processors 510.

When the device 500 is acting as, or part of, the electronic control unit 210, the processor 510, when executing the instructions 530, causes the device 500 to perform actions to implement the method 300 and process 400 described above with reference to fig. 1-3. The actions include: determining whether there is a rear collision risk of the vehicle being rear-ended by a rear vehicle; predicting whether there is a front collision risk of the vehicle colliding with a front obstacle in response to the presence of the rear collision risk; in response to the presence of a front collision risk, calculating a collision location at which the rear vehicle is expected to rear-end collide and a velocity at the collision location; and determining a braking strategy to be executed by the vehicle based on the collision location and the speed.

In some embodiments, the actions further include: and controlling the vehicle to send out a reminding signal to a driver of the vehicle in response to the existence of the rear collision risk.

In certain embodiments, the action includes satisfying at least one of the following, without executing a braking strategy: the current speed of the vehicle is greater than a first vehicle speed threshold; the current vehicle speed of the vehicle is less than a second vehicle speed threshold; eliminating rear collision risk or front collision risk; and detecting an active operation of the vehicle by a driver of the vehicle.

In some embodiments, determining the braking strategy to provide braking force to the vehicle before the rear-end collision includes: calculating a collision reference distance and a braking distance in a limit situation for the limit situation in which the maximum braking force is provided to the vehicle before the rear-end collision occurs; and in response to the difference between the collision reference distance and the braking distance in the limit situation being smaller than a second threshold value, determining the braking strategy to control the vehicle to give out a visual and/or audible warning signal for the front obstacle, and immediately controlling the vehicle to perform braking with a braking force corresponding to the maximum deceleration. In some embodiments, determining the braking strategy of the vehicle further comprises: and determining the braking strategy to immediately control the vehicle to perform braking with the maximum braking force in response to the difference between the collision reference distance and the braking distance in the limit situation being greater than or equal to a second threshold value.

Embodiments of the present invention also provide a computer readable storage medium having stored thereon machine-readable instructions which, when executed by a machine, cause the machine to perform a method described in accordance with the present invention.

Those of skill in the art will understand that the logic and/or steps represented in the flowcharts or otherwise described herein, e.g., an ordered listing of executable instructions that can be viewed as implementing logical functions, can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. For the purposes of this description, a "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device.

More specific examples (a non-exhaustive list) of the computer-readable medium would include the following: an electrical connection (electronic device) having one or more wires, a portable computer diskette (magnetic device), a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium could even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, via for instance optical scanning of the paper or other medium, then compiled, interpreted or otherwise processed in a suitable manner if necessary, and then stored in a computer memory.

It should be understood that portions of the present invention may be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the various steps or methods may be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any one or combination of the following techniques, which are known in the art, may be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application specific integrated circuit having an appropriate combinational logic gate circuit, a Programmable Gate Array (PGA), a Field Programmable Gate Array (FPGA), or the like.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiment. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method of avoiding a secondary collision of a road vehicle, comprising:

determining whether there is a rear collision risk of the vehicle being rear-ended by a rear vehicle;

predicting whether there is a front collision risk of the vehicle colliding with a front obstacle in response to the presence of the rear collision risk;

in response to the presence of the front collision risk, calculating a collision location at which the rear vehicle is expected to rear-end collide and a velocity at the collision location;

calculating a collision reference distance of the vehicle from the front obstacle at the time of an expected rear-end collision, based on the characteristic parameters of the front obstacle acquired by the vehicle detection device and the collision position;

calculating a braking distance required for the vehicle to perform a maximum deceleration that the vehicle can perform to bring the vehicle close to a stop when an expected rear-end collision occurs, based on a speed of the rear vehicle at the collision location; and

in response to the difference between the collision reference distance and the braking distance being greater than or equal to a second threshold value, determining the braking strategy to control the vehicle to perform braking at a braking force that depends on the braking distance upon a rear-end collision; alternatively, in response to the difference between the collision reference distance and the braking distance being less than the second threshold, determining the braking strategy to provide braking force to the vehicle before a rear-end collision occurs.

2. The method of claim 1, wherein determining whether the rear collision risk exists comprises:

calculating a collision time of the rear vehicle with the vehicle based on the characteristic parameters of the rear vehicle acquired by a vehicle detection device, wherein the collision time represents a period of time from the current time of the rear vehicle to the occurrence of the expected rear-end collision; and

determining that the rear collision risk exists in response to the time-to-collision being less than a first threshold.

3. The method of claim 1, wherein predicting whether the front collision risk exists comprises:

predicting a motion trajectory of the front obstacle based on the characteristic parameters of the front obstacle acquired by a vehicle detection device;

determining whether the motion trajectory overlaps with a trajectory of the vehicle after an expected rear-end collision; and

determining that the front impact risk exists in response to the motion trajectory overlapping a trajectory of the vehicle after an expected rear-end impact.

4. The method of claim 1, wherein determining the braking strategy to provide braking force to the vehicle prior to the rear-end collision comprises:

calculating a collision reference distance and a braking distance in a limit situation in which a maximum braking force is provided to the vehicle before a rear-end collision occurs; and

in response to the difference between the collision reference distance and the braking distance in the limit situation being smaller than the second threshold value, determining the braking strategy to control the vehicle to give out a visual and/or audible warning signal for the front obstacle, and immediately controlling the vehicle to perform braking with a braking force corresponding to the maximum deceleration.

5. The method of claim 4, wherein determining the braking strategy of the vehicle further comprises:

determining the braking strategy to immediately control the vehicle to perform braking at the maximum braking force in response to a difference between the collision reference distance and the braking distance in the limit situation being greater than or equal to the second threshold value.

6. A system for avoiding a secondary collision of a road vehicle, comprising:

an environment detection component for detecting characteristic parameters of a vehicle behind the vehicle and a front obstacle;

an electronic control unit that determines whether there is a rear collision risk that the vehicle is rear-ended by a rear vehicle and a front collision risk that the vehicle collides with a front obstacle, based on the characteristic parameters detected by the environment detection component; in response to the presence of the rear collision risk and the front collision risk, calculating a collision location at which a rear-end collision of the rear vehicle will occur and a velocity at the collision location; and determining a braking strategy to be executed by the vehicle based on the collision location and the speed; and

a braking system for performing vehicle braking in accordance with the determined braking strategy,

wherein determining a braking strategy to be implemented by the vehicle based on the collision location and the speed comprises:

calculating a collision reference distance of the vehicle from the front obstacle at the time of a rear-end collision, based on the characteristic parameters of the front obstacle acquired by the vehicle detection device and the collision position;

7. An electronic device, comprising:

a processor; and

a memory storing instructions that, when executed by the processor, cause the apparatus to perform the method of any of claims 1-5.