An avoidance system and method for identifying the danger of following vehicles based on energy loss

Abstract

The present invention provides an avoidance system and method for identifying the danger of a rear vehicle based on energy loss, comprising: collecting image information, driving speed and driving distance between the rear vehicle and the vehicle, obtaining the size information of the rear vehicle according to the image information; obtaining the driving conditions of the front and side lanes; obtaining the mass threshold, energy loss threshold and safe driving distance according to the size information of the rear vehicle; estimating the energy loss of the collision between the rear vehicle and the vehicle according to the driving speed and mass threshold of the rear vehicle and the driving speed and mass of the vehicle, comparing the energy loss of the rear vehicle with the energy loss threshold, and comparing the driving distance between the rear vehicle and the vehicle with the safe driving distance to determine whether there is a risk, and if there is a risk, taking avoidance measures according to the driving conditions of the front and side lanes. The present invention can determine the threat to the driving of the vehicle by the kinetic energy generated by different models of vehicles at different speeds at the rear, so that the vehicle can make emergency avoidance in time.

Description

Technical Field

[0001] The present invention belongs to the technical field of automotive traffic safety, and particularly relates to an avoidance system and method for identifying the danger of a rear vehicle based on energy loss. Background Art

[0002] In real life, a driver's attention often focuses on the front. Inevitably, when there is an abnormality in the driving state of a rear vehicle, such as abnormal braking, the reaction time left for the front driver is not enough to ensure their life safety.

[0003] Currently, the rear vehicle detection systems on the market often use speed thresholds and distance thresholds as the risk assessment criteria for the rear driving situation. Under this risk judgment mechanism, it is impossible to give a reasonable loss assessment for different vehicle models at different speeds. Summary of the Invention

[0004] To solve the above problems of the prior art, the present invention provides an avoidance system and method for identifying the danger of a rear vehicle based on energy loss, which can judge the threat to the driving of the vehicle by the kinetic energy generated by different vehicle models of the rear vehicle at different speeds, so that the vehicle can make an emergency avoidance in time.

[0005] The present invention is achieved through the following technical solutions:

[0006] An avoidance method for identifying the danger of a rear vehicle based on energy loss, comprising:

[0007] Collect the image information, driving speed and driving distance between the rear vehicle and the vehicle itself, and obtain the size information of the rear vehicle according to the image information;

[0008] Obtain the driving road conditions of the front and both sides of the lane;

[0009] Compare the size information of the rear vehicle with the data in the vehicle model database to obtain the mass threshold, energy loss threshold and safe driving distance of the rear vehicle; the vehicle model database stores the sizes, mass thresholds, energy loss thresholds and safe driving distances corresponding to different vehicle models;

[0010] Estimate the energy loss of the collision between the rear vehicle and the vehicle itself according to the driving speed and mass threshold of the rear vehicle and the driving speed and mass of the vehicle itself, compare the energy loss of the rear vehicle with the energy loss threshold, and compare the driving distance between the rear vehicle and the vehicle itself with the safe driving distance to judge whether there is a risk. If there is a risk, take avoidance measures according to the driving road conditions of the front and both sides of the lane.

[0011] Preferably, it further comprises:

[0012] Compare the driving speed of the vehicle behind with the driving speed of the vehicle itself, and compare the driving distance between the vehicle behind and the vehicle itself with the safe driving distance. If the driving speed of the vehicle behind is greater than the driving speed of the vehicle itself, and the driving distance between the vehicle behind and the vehicle itself is greater than the safe driving distance, then give a warning to the driver of the vehicle itself and / or the vehicle behind to remind the driver to take evasive measures.

[0013] Preferably, compare the energy loss of the vehicle behind with the energy loss threshold, and compare the driving distance between the vehicle behind and the vehicle itself with the safe driving distance to determine whether there is a risk. If there is a risk, take evasive measures according to the driving conditions of the front and both sides of the lane, specifically including:

[0014] If the energy loss of the vehicle behind is greater than the energy loss threshold, and the driving distance between the vehicle behind and the vehicle itself is greater than the safe driving distance, then it is considered risky, and a warning is given to the driver of the vehicle itself and / or the vehicle behind to remind the driver to take evasive measures;

[0015] If the energy loss of the vehicle behind is greater than the energy loss threshold, and the driving distance between the vehicle behind and the vehicle itself is less than the safe driving distance, then it is considered risky, and the vehicle itself is controlled to automatically take evasive measures according to the driving conditions of the front and both sides of the lane.

[0016] Preferably, compare the energy loss of the vehicle behind with the energy loss threshold, and compare the driving distance between the vehicle behind and the vehicle itself with the safe driving distance to determine whether there is a risk. If there is a risk, take evasive measures according to the driving conditions of the front and both sides of the lane, specifically including:

[0017] If the energy loss of the vehicle behind is greater than the energy loss threshold, and the driving distance between the vehicle behind and the vehicle itself is greater than the safe driving distance, then it is considered risky, and a warning is given to the driver of the vehicle behind;

[0018] If the energy loss of the vehicle behind is greater than the energy loss threshold, and the driving distance between the vehicle behind and the vehicle itself is less than the safe driving distance and greater than the preset critical safe driving distance, then it is considered risky, and a warning is given to the driver of the vehicle itself to remind the driver to take evasive measures; the critical safe driving distance is pre-stored in the vehicle type database;

[0019] If the energy loss of the vehicle behind is greater than the energy loss threshold, and the driving distance between the vehicle behind and the vehicle itself is less than the critical safe driving distance, then it is considered risky, and the vehicle itself is controlled to automatically take evasive measures according to the driving conditions of the front and both sides of the lane.

[0020] Preferably, control the vehicle itself to automatically take evasive measures according to the driving conditions of the front and both sides of the lane, specifically including:

[0021] According to the driving conditions of the lanes on both sides, determine whether the lane-changing conditions are met. If the lane-changing conditions are met, control the vehicle to automatically change lanes; if the lane-changing conditions are not met, determine whether the accelerating escape lane-changing conditions are met according to the driving conditions ahead. If the accelerating escape lane-changing conditions are met, control the vehicle to automatically accelerate to the same speed as the vehicle behind. If the accelerating escape lane-changing conditions are not met, control the vehicle to automatically move closer to one lane according to the driving conditions of the lanes on both sides to avoid the vehicle behind.

[0022] Further, obtain the driving conditions of the lanes ahead and on both sides. Specifically: collect the image information, driving speed, acceleration, and driving distance between the vehicle and the host vehicle of the vehicle in the front side and the rear side, and collect the image information, driving speed, and acceleration of the vehicle ahead to obtain the driving conditions of the lanes ahead and on both sides;

[0023] According to the driving conditions of the lanes on both sides, determine whether the lane-changing conditions are met. Specifically: according to the driving conditions of the lanes on both sides, determine whether the following three conditions are met. If so, it is considered that the lane-changing conditions are met;

[0024] The distance between the host vehicle and the vehicle in the rear side satisfies:

[0025]

[0026] S r1 (0) = h FM -l M

[0027] S MF (v) = ∫ 0 t ∫ 0 λ a M (τ) - a F (τ)dτdλ + (v M (0) - v F (0))

[0028] S r1 (0) is the initial vehicle distance between the host vehicle and the vehicle in the rear side;

[0029] h FM is the initial head distance between the vehicle in the rear side and the host vehicle;

[0030] v F (0), v M (0) are the driving speeds of the vehicle in the rear side and the host vehicle at the start of lane change respectively;

[0031] a F (τ), a M (τ) are the accelerations of the vehicle in the rear side and the host vehicle at time τ respectively;

[0032] is the critical lane - changing time when the vehicle contacts the vehicle behind it on the side;

[0033] t end is the lane - changing completion time;

[0034] l M is the vehicle body length of this vehicle;

[0035] The distance between this vehicle and the vehicle in front satisfies:

[0036]

[0037]

[0038]

[0039] S r2 (0) is the initial vehicle - to - vehicle distance between the vehicle in front on the original lane and the lane - changing vehicle;

[0040] is the dynamic vehicle - to - vehicle distance between the lane - changing vehicle and the vehicle in front on the current lane;

[0041] is the critical lane - changing time when this vehicle contacts the vehicle in front;

[0042] is the driving speed of the vehicle in front at the start of lane - changing;

[0043] is the acceleration of the vehicle in front at time τ;

[0044] The initial distance between this vehicle and the vehicle in front on the side satisfies:

[0045]

[0046]

[0047]

[0048] S r3 (0) is the initial vehicle - to - vehicle distance between the vehicle in front on the target lane and the lane - changing vehicle;

[0049] is the dynamic vehicle - to - vehicle distance between the lane - changing vehicle and the vehicle in front on the target lane;

[0050] is the critical lane - changing time when this vehicle contacts the vehicle in front on the side;

[0051] is the driving speed of the vehicle in front on the side at the start of lane - changing;

[0052] is the acceleration of the vehicle in the side front at time τ.

[0053] A collision avoidance system for identifying the danger of a rear vehicle based on energy loss, comprising: an information acquisition module, a central control unit, and an execution module;

[0054] The information acquisition module is used to collect the image information, driving speed and driving distance between the rear vehicle and the own vehicle, and obtain the driving road conditions of the front and both sides of the lane;

[0055] The central control unit is used to obtain the size information of the rear vehicle according to the image information of the rear vehicle; compare the size information of the rear vehicle with the data in the vehicle type database to obtain the mass threshold, energy loss threshold and safe driving distance of the rear vehicle; different vehicle types' sizes, mass thresholds, energy loss thresholds and safe driving distances are stored in the vehicle type database; estimate the energy loss of the collision between the rear vehicle and the own vehicle according to the driving speed and mass threshold of the rear vehicle and the driving speed and mass of the own vehicle, compare the energy loss of the rear vehicle with the energy loss threshold and the driving distance with the safe driving distance respectively to judge whether there is a risk, and if there is a risk, control the execution module to take avoidance measures and / or remind the driver of the own vehicle to take avoidance measures according to the driving road conditions of the front and both sides of the lane.

[0056] Preferably, the information acquisition module includes a millimeter wave radar and a camera;

[0057] The millimeter wave radar includes a rear millimeter wave radar and side millimeter wave radars. The side millimeter wave radars include two side front millimeter wave radars and two side rear millimeter wave radars; the camera includes a front camera, a rear camera and two side cameras;

[0058] The rear millimeter wave radar is used to collect the driving speed of the rear vehicle and the driving distance between the rear vehicle and the own vehicle;

[0059] The side front millimeter wave radar is used to collect the driving speed, acceleration of the vehicle in the side front and the driving distance between the side front vehicle and the own vehicle;

[0060] The side rear millimeter wave radar is used to collect the driving speed, acceleration of the vehicle in the side rear and the driving distance between the side rear vehicle and the own vehicle;

[0061] The rear camera is used to collect the image information of the rear vehicle;

[0062] The front camera is used to collect the image information, driving speed, acceleration and lane line information of the front vehicle;

[0063] The side camera is used to collect the image information of the vehicle in the front side and the vehicle in the rear side.

[0064] Preferably, the execution module includes a steering system and a motor gearbox;

[0065] When the central control unit determines that there is a risk, it controls the steering system to perform a lane change operation according to the driving conditions in the front, front side and rear side, or controls the motor gearbox to perform an acceleration operation.

[0066] Furthermore, the execution module includes a linear vibration motor installed on the steering wheel;

[0067] When the central control unit determines that there is a risk, it controls the linear vibration motor to vibrate to remind the driver of the vehicle to take avoidance measures;

[0068] And / or, the execution module includes a buzzer. When the central control unit determines that there is a risk, it controls the buzzer to beep to remind the driver of the vehicle to take avoidance measures.

[0069] Compared with the prior art, the present invention has the following beneficial effects:

[0070] The present invention is a method for judging whether avoidance measures need to be taken based on the threat to the driving of the vehicle caused by the kinetic energy generated by different vehicle types and different vehicle speeds at the rear. According to the image information of the vehicle at the rear, its size is processed and compared with the data in the vehicle type database, so as to judge the vehicle type of the vehicle at the rear, obtain the energy loss threshold and safe driving distance for this vehicle type, estimate the energy loss of the collision between the vehicle at the rear and the vehicle, and comprehensively judge the rear-end collision risk in combination with the comparison result of the energy loss and the energy loss threshold and the comparison result of the distance between the vehicle at the rear and the vehicle and the safe driving distance, and take avoidance measures in time according to the judgment result to ensure the safety of the driver. It is known from experience that under different speed conditions, different vehicle types generate different kinetic energies due to their different masses, and the resulting collisions cause different damages to the vehicle. Compared with the anti-rear impact model set for the rear speed threshold, the system of the present invention divides the threat degree at the rear more carefully, can improve the driving experience more fully under the condition of ensuring the safety of the driver, so under the condition of less loss, giving a reasonable safe driving distance and corresponding avoidance strategies will bring a better driving experience to the driver.

[0071] Furthermore, in order to reduce the influence caused by the driver's lack of attention to the rear, when the driving distance between the vehicle at the rear and the vehicle is greater than the safe driving distance, but the speed of the vehicle at the rear is greater than the speed of the vehicle, the driver is warned to remind the driver to take avoidance measures.

[0072] Further, the method of the present invention is divided into different stages. First, a warning is given to the driver of the vehicle. If the driver still does not take evasive measures after the warning, the control of the vehicle is taken over at the critical safe driving distance where the driver is unable to make corresponding evasive maneuvers to complete autonomous driving evasion. The warning can enhance the driver's good driving experience, and autonomous driving can ensure the implementation of emergency evasive measures to ensure the safety of the driver.

[0073] Further, the present invention provides various evasive measures such as lane change, acceleration, and avoidance, which can ensure the safety of the driver to the greatest extent. Description of the Drawings

[0074] Figure 1 Schematic diagram of the safe driving distance of different vehicle models;

[0075] Figure 2 Schematic diagram of the emergency lane change strategy provided by the system;

[0076] Figure 3 Schematic diagram of the acceleration and escape lane change strategy provided by the system;

[0077] Figure 4 Schematic diagram of the emergency avoidance strategy provided by the system;

[0078] Figure 5 Flowchart of the method of the present invention;

[0079] Figure 6 Installation position diagram of the system monitoring module (top view);

[0080] Figure 7 Installation position diagram of the system monitoring module (side view);

[0081] Figure 8 Schematic diagram of critical point 1;

[0082] Figure 9 Schematic diagram of critical point 2;

[0083] Figure 10 Schematic diagram of critical point 3;

[0084] 1, 2 - Side front millimeter-wave radar; 3, 4 - Side rear millimeter-wave radar; 5 - Rear millimeter-wave radar; 6 - Front camera; 7 - Rear camera; 8, 9 - Side cameras; 10 - Buzzer; 11 - Linear vibration motor. Detailed Embodiments

[0085] To further understand the present invention, the present invention will be described below in conjunction with embodiments. These descriptions are only to further explain the features and advantages of the present invention and are not used to limit the claims of the present invention.

[0086] The avoidance system for identifying the danger of the rear vehicle based on energy loss of the present invention includes an information acquisition module, a central control unit, and an execution module;

[0087] The information acquisition module is used to collect the image information of the rear vehicle, the front vehicle, the front-side vehicle, and the rear-side vehicle; collect the driving speeds of the rear vehicle, the front-side vehicle, and the rear-side vehicle and the driving distances between them and the vehicle itself;

[0088] The central control unit is used to obtain the size information of the rear vehicle according to the image information of the rear vehicle; obtain the driving road conditions of the front and both sides of the lane according to the image information, driving speeds, and driving distances between the front vehicle, the front-side vehicle, and the rear-side vehicle and the vehicle itself; compare the size information of the rear vehicle with the data in the vehicle type database to obtain the mass threshold, energy loss threshold, and safe driving distance of the rear vehicle; different vehicle types' sizes, mass thresholds, energy loss thresholds, and safe driving distances are stored in the vehicle type database; estimate the energy loss of the collision between the rear vehicle and the vehicle itself according to the driving speed and mass threshold of the rear vehicle and the driving speed and mass of the vehicle itself, compare the energy loss of the rear vehicle with the energy loss threshold and the driving distance with the safe driving distance respectively to judge whether there is a risk, and if there is a risk, control the execution module to take avoidance measures and / or remind the driver of the vehicle to take avoidance measures according to the driving road conditions of the front and both sides of the lane.

[0089] The information acquisition module includes a millimeter-wave radar and a camera;

[0090] As Figure 6 and Figure 7 shown, the millimeter-wave radar includes a rear millimeter-wave radar 6 and side millimeter-wave radars. The side millimeter-wave radars include two front-side millimeter-wave radars 1, 2 and two rear-side millimeter-wave radars 4, 5; the camera includes a front camera 6, a rear camera 7, and two side cameras 8, 9;

[0091] The rear millimeter-wave radar, which is a long-range millimeter-wave radar, is installed in the middle of the vehicle's rear bumper and is used to collect the driving speed of the rear vehicle and the driving distance between it and the vehicle itself;

[0092] The front-side millimeter-wave radar, which is a short-range millimeter-wave radar, is installed under the vehicle's headlight, one on each of the left and right sides, and is used to collect the driving speed, acceleration, and driving distance between the front-side vehicle and the vehicle itself;

[0093] The rear-side millimeter-wave radar, which is a short-range millimeter-wave radar, is installed at both ends of the vehicle's rear bumper and is used to collect the driving speed, acceleration, and driving distance between the rear-side vehicle and the vehicle itself;

[0094] The rear camera is installed in the exact middle above the rear license plate of the vehicle, and is used to collect the image information of the rear vehicle and ensure the recognition of lane lines;

[0095] The front camera is installed in the exact middle above the front windshield of the vehicle, and is used to collect the image information, driving speed and acceleration of the front vehicle and ensure the recognition of lane lines;

[0096] The side cameras are installed below the two side rearview mirrors of the vehicle, and are used to collect the image information of the front side vehicle and the rear side vehicle.

[0097] The execution module of the present invention includes a steering system and a motor gearbox;

[0098] When the central control unit determines that there is a risk, it controls the steering system to perform a lane change operation according to the driving conditions of the front and both side lanes, or controls the motor gearbox to perform an acceleration operation.

[0099] The execution module of the present invention further includes a buzzer 10 and a linear vibration motor 11. The linear vibration motor is installed on the steering wheel and is used to give a vibration reminder to the driver within the first-stage detection range. The buzzer is installed in the horn and is used to give a warning to the driver within the second-stage detection range.

[0100] An avoidance method based on energy loss for identifying the danger of a rear vehicle in the present invention includes:

[0101] Collect the image information, driving speed and driving distance between the rear vehicle and the own vehicle, and obtain the size information of the rear vehicle according to the image information;

[0102] Collect the image information, driving speed, acceleration and driving distance between the front side vehicle and the rear side vehicle and the own vehicle, and collect the image information of the front vehicle to obtain the driving conditions of the front and both side lanes;

[0103] Compare the size information of the rear vehicle with the data in the vehicle type database to obtain the mass threshold, energy loss threshold and safe driving distance of the rear vehicle; different vehicle types' sizes, mass thresholds, energy loss thresholds and safe driving distances are stored in the vehicle type database;

[0104] Estimate the energy loss of the collision between the rear vehicle and the own vehicle according to the driving speed and mass threshold of the rear vehicle and the driving speed and mass of the own vehicle, compare the energy loss of the rear vehicle with the energy loss threshold, and compare the driving distance between the rear vehicle and the own vehicle with the safe driving distance to determine whether there is a risk. If there is a risk, take avoidance measures according to the driving conditions of the front and both side lanes.

[0105] A specific implementation manner is given below

[0106] The avoidance method for identifying the danger of the following vehicle based on energy loss in the present invention includes three stages, as Figure 5 shown, and the specific introduction is as follows:

[0107] The first stage: When the following vehicle appears within the monitoring range L of the rear millimeter-wave radar r , the rear millimeter-wave radar detects the driving speed V of the following vehicle, and the rear camera collects the image information of the following vehicle; the central control unit compares the driving speed V of the following vehicle with the current driving speed of the vehicle. If the driving speed of the following vehicle exceeds the current driving speed of the vehicle, it is determined that the speed is abnormal, and then it is judged whether the turn signal of the following vehicle is on and whether the following vehicle runs over the lane line according to the image information of the following vehicle collected by the rear camera to judge whether it has a turning intention. If the turn signal is not on, the central control unit controls the linear motor on the steering wheel in the cab to generate vibration to give a preliminary reminder to the driver. The central control unit determines whether the following vehicle has a decelerating tendency according to the driving speed V of the following vehicle. When it has no decelerating tendency, when it enters the detection range L of the rear camera C , the central control unit determines the vehicle type of the following vehicle according to the image information of the following vehicle collected by the rear camera. The main method is to compare the width and height of the following vehicle in the image information with the data in the vehicle type database at a specific distance difference, and further determine its vehicle type to obtain the corresponding energy loss threshold and safe driving distance.

[0108] In the central control unit of the present invention, there is a vehicle type database, which stores the width range, height range, mass threshold M 1 , energy loss threshold and safe driving distance of different vehicle type vehicles statistically according to the existing vehicle types in the market. The kinetic energy difference (energy loss) generated by the following vehicle and the vehicle itself: P = FL, where F is the rear impact force that the vehicle can accept without affecting the driver's safety and is a known value; therefore, the safe driving distance L in the second stage between the two vehicles x can be calculated by using the energy loss threshold and F. The critical safe driving distance in the third stage is set by a fixed driving distance.

[0109] The width range, height range and mass information of different vehicle type vehicles are as follows:

[0110] The width of a passenger car is 1.6M - 1.8M, its height is 1.4M - 1.6M, and the total mass is about 1.4t;

[0111] The width of a sports utility vehicle is 1.7M - 2.0M, the height is 1.6M - 1.8M, and the total mass is about 1.8t;

[0112] The width of the minibus is 1.45M - 1.55M, the height is 1.75M - 1.85M, and the total mass is about 2.4t;

[0113] The width of the minibus is 2.2M - 2.4M, the height is 2.7M - 2.8M, and the total mass is about 11.0t;

[0114] The width of the large bus is 2.4M - 2.6M, the height is 3.3M - 3.6M, and the total mass is about 11.0t;

[0115] The width of the 3.5 - ton truck is 2.0M - 2.3M, the height is 2.1M - 2.3M, and the total mass is about 8.0t;

[0116] The width of the 8.0 - ton truck is 1.9 - 2.0M, the height is 1.8M - 2.0M, and the total mass is about 13.0t;

[0117] The width of the 8.0 - ton truck (for container luggage consignment) is about 2.3 - 2.4M, the height is 2.7M, and the total mass is about 21.0t;

[0118] The width of the flatbed truck is about 2.4 - 2.6M, the height is 3.7 - 4.0M, and the total mass is about 18.0t.

[0119] Classify the vehicles behind, and set the safe driving distance and energy loss threshold respectively for vehicles of different models, as Figure 1 shown. The specific scheme is as follows:

[0120] When the vehicle behind is a passenger car, set the safe driving distance and energy loss threshold in the second stage to be L 1 , P 1 ; The critical safe driving distance in the third stage is L 11 .

[0121] When the vehicle behind is a sports utility vehicle, set the safe driving distance and energy loss threshold in the second stage to be L 2 , P 2 ; The critical safe driving distance in the third stage is L 22 .

[0122] When the vehicle behind is a minibus or a similar model, set the safe driving distance and energy loss threshold in the second stage to be L 3 , P 3 ; The critical safe driving distance in the third stage is L 33 .

[0123] When the vehicle behind is a minibus, set the safe driving distance and energy loss threshold in the second stage to be L 4 , P4 ; The critical safe driving distance in the third stage is L 44 .

[0124] When the vehicle behind is a large bus, the energy loss thresholds for setting the safe driving distance in the second stage are L 5 、P 5 ; The critical safe driving distance in the third stage is L 55 .

[0125] When the vehicle behind is a large vehicle such as a 3.5-ton truck, the safe driving distance and energy loss thresholds for setting the second stage are L 6 、P 6 ; The safe driving distance in the third stage is L 66 .

[0126] When the vehicle behind is an 8.0-ton truck, the safe driving distance and energy loss thresholds for setting the second stage are L 7 、P 7 ; The critical safe driving distance in the third stage is L 77 .

[0127] When the vehicle behind is an 8.0-ton truck (container luggage consignment), the safe driving distance and energy loss thresholds for setting the second stage are L 8 、P 8 ; The critical safe driving distance in the third stage is L 88 .

[0128] When the vehicle behind is a high-sided truck, the safe driving distance and energy loss thresholds for setting the second stage are L 9 、P 9 ; The critical safe driving distance in the third stage is L 99 .

[0129] After initially determining the vehicle type and energy loss threshold of the vehicle behind, calculate the estimated energy loss at the current moment (the kinetic energy difference between this vehicle and the vehicle behind) P, where M 1 and M 2 are the masses of the vehicle behind and this vehicle respectively, and v 1 and v 2 are the speeds of the vehicle behind and this vehicle respectively, so as to determine the masses of different vehicle types and the energy losses caused by different vehicle speeds.

[0130] When the safe driving distance in the second stage has not been reached, but the estimated energy loss caused by the vehicle behind reaches the corresponding pre-set energy loss threshold P 1 、P 2 、P 3 、P 4 、P5 , P 6 , P 7 , P 8 or P 9 , at this time, the central control unit controls the vehicle taillights to emit stroboscopic light to give a visual reminder to the following vehicle.

[0131] The second stage: The central control unit judges that the driving distance between the following vehicle and the vehicle itself reaches the corresponding pre-set safe driving distance L according to the driving distance and driving speed between the following vehicle and the vehicle itself collected by the rear millimeter-wave radar. 1 , L 2 , L 3 , L 4 , L 5 , L 6 , L 7 , L 8 or L 9 , if the estimated energy loss P that may be caused is still greater than the set energy loss threshold, the central control unit controls the buzzer in the cab to remind the driver and urge him to make corresponding avoidance strategies. At the same time, the front camera, side camera, front-side millimeter-wave radar, and rear-side millimeter-wave radar are turned on to detect the driving conditions in front of the vehicle's driving lane and in front of and behind the two side lanes. The central control unit judges the position of the surrounding vehicles at present according to the driving conditions in front of the vehicle's driving lane and on both sides, and detects whether there are pedestrians and obstacles around. If the estimated loss energy P value at this time has dropped below the energy loss threshold (here it can be understood as the vehicle speed decreases) or it is detected that the following vehicle has left the vehicle's driving lane, the vehicle taillight stroboscopic system and the buzzer are turned off and enter the standby mode, otherwise enter the third stage.

[0132] The third stage: When the following vehicle enters the corresponding critical safe driving distance L 11 , L 22 , L 33 , L 44 , L 55 , L 66 , L 77 , L 88 or L 99 , if the estimated energy loss P value at this time still exceeds the energy loss threshold, the central control unit takes over the vehicle's steering system and the motor gearbox to perform emergency avoidance or emergency lane change or acceleration escape lane change.

[0133] The main strategies for emergency avoidance or emergency lane change are as follows:

[0134] Strategy 1: Emergency Lane Change: The central control unit obtains the driving conditions of the lanes in front and on both sides based on the image information collected by the front camera and the side cameras, the driving speed of the vehicle in the front side and the driving distance between the vehicle in the front side and the host vehicle collected by the side front millimeter-wave radar, and the driving speed of the vehicle in the rear side and the driving distance between the vehicle in the rear side and the host vehicle collected by the side rear millimeter-wave radar, and determines whether a lane change is possible. The specific determination conditions are given as follows:

[0135] The distance between the lane-changing vehicle (the host vehicle) and the vehicle behind in the target lane (the vehicle in the rear side) should satisfy:

[0136]

[0137] S r1 (0) = h FM -l M

[0138]

[0139] S r1 (0) is the initial vehicle distance between the vehicle behind in the target lane and the lane-changing vehicle;

[0140] S MF (v) is the dynamic vehicle distance between the vehicle behind in the target lane and the lane-changing vehicle;

[0141] h FM is the initial headway between the vehicle behind in the target lane and the lane-changing vehicle;

[0142] v F (0), v M (0) are the driving speeds of the vehicle behind in the target lane and the lane-changing vehicle at the start of the lane change respectively;

[0143] a F (τ), a M (τ) are the accelerations of the vehicle behind in the target lane and the lane-changing vehicle at time τ respectively;

[0144] is the time for the lane-changing vehicle to reach critical point 1 (i.e., the critical lane-changing time when the host vehicle contacts the vehicle in the rear side);

[0145] t end is the lane change completion time;

[0146] l M is the body length of the lane-changing vehicle.

[0147] When changing lanes, when the lane-changing vehicle reaches critical point 1, given by Figure 8 the left rear corner of the lane-changing vehicle body and the right side of the vehicle body of the vehicle behind in the target lane are on the same horizontal line,

[0148] Thus, the limit position of lane change and the critical lane-changing time are determined. That is:

[0149]

[0150] y lat is the lateral displacement of the lane-changing vehicle relative to the center line of the original lane;

[0151] L lane is the distance between two lane lines;

[0152] is the yaw angle of the lane-changing vehicle, and a fixed value of 4° is selected considering driving experience and lane-changing stability;

[0153] w M and w F are the body widths of the lane-changing vehicle and the vehicle behind in the target lane respectively.

[0154] In summary, the initial headway h between the vehicle behind in the lane and the lane-changing vehicle FM should satisfy:

[0155]

[0156] The distance between the lane-changing vehicle and the vehicle in front in the original lane (the current driving lane of this vehicle) should satisfy:

[0157]

[0158]

[0159]

[0160] S r2 (0) is the initial headway between the vehicle in front in the original lane and the lane-changing vehicle;

[0161] is the dynamic headway between the lane-changing vehicle and the vehicle in front in the current lane;

[0162] is the time when the lane-changing vehicle reaches the critical point 2 (i.e., the critical lane-changing time when this vehicle contacts the vehicle in front);

[0163] is the driving speed of the vehicle in front in the original lane at the start of lane change;

[0164] is the acceleration of the vehicle in front in the original lane at time τ.

[0165] When changing lanes, when the lane-changing vehicle reaches the critical point 2, from Figure 9Given that the right front corner of the lane-changing vehicle's body is on the same horizontal line as the left side of the vehicle in front in the original lane, the lane-changing limit position and the critical lane-changing time are determined accordingly. That is, at this time:

[0166]

[0167] is the body width of the vehicle in front in the original lane.

[0168] That is, the initial headway between the vehicle in front in the original lane and the lane-changing vehicle should satisfy:

[0169]

[0170] The initial distance between the lane-changing vehicle and the vehicle in front in the target lane (the vehicle on the side in front) should allow the vehicle to safely change lanes and enter, and should satisfy:

[0171]

[0172]

[0173]

[0174] S r3 (0) is the initial headway between the vehicle in front in the target lane and the lane-changing vehicle;

[0175] is the dynamic headway between the lane-changing vehicle and the vehicle in front in the target lane;

[0176] is the time when the lane-changing vehicle reaches the critical point 3 (i.e., the critical lane-changing time when the vehicle contacts the vehicle on the side in front);

[0177] is the driving speed of the vehicle in front in the target lane at the start of lane change;

[0178] is the acceleration of the vehicle in front in the target lane at time τ.

[0179] When changing lanes, when the lane-changing vehicle reaches the critical point 3, if Figure 10 , the right front corner of the lane-changing vehicle's body and the left side of the vehicle in front in the target lane are on the same horizontal line, and the lane-changing limit position and the critical time are determined accordingly. That is, at this time:

[0180]

[0181] is the body width of the vehicle in front in the target lane.

[0182] According to the above content, the initial headway between the vehicle in front on the target lane and the lane-changing vehicle shall satisfy:

[0183]

[0184] If the above three conditions are met, the lane-changing condition is satisfied, and the central control unit controls the steering system to steer the vehicle to change lanes, as Figure 2 shown.

[0185] Strategy 2: Accelerated escape lane change:

[0186] Under the condition that the lane-changing conditions are not met on both sides in the third stage and it is determined according to the image information collected by the front camera that there are no vehicles driving in front on the original lane:

[0187] Based on the set critical safe driving distance in the third stage and the driving speed of the vehicle behind entering the third stage, calculate the acceleration time of this vehicle The central control unit controls the motor gearbox to make this vehicle complete acceleration to the same speed as the vehicle behind within the Figure 3 time period, accelerate the vehicle to move forward, and at the same time monitor the driving conditions of both lanes. When the lane-changing conditions are met on both lanes, execute the emergency lane-changing strategy, as

[0188]

[0189]

[0190] S MB (v) is the dynamic distance between the vehicle behind on this lane and the accelerating escape vehicle;

[0191] L xx is the safe driving distance set in the third stage;

[0192] v M (0) is the initial speed when the accelerating escape vehicle is ready to accelerate;

[0193] v B (0) is the driving speed of the vehicle behind on this lane;

[0194] a B (τ) is the acceleration of the vehicle behind on this lane;

[0195] a M (τ) is the acceleration value adopted by this vehicle;

[0196] Strategy 3: Emergency avoidance:

[0197] Under the condition that neither Strategy 1 nor Strategy 2 can be executed, the central control unit determines the lane width based on the lane line information collected by the front camera, and determines the distance S of the vehicles driving on both sides from the inner lane line according to the image information collected by the front camera, and controls the vehicle to preferentially approach the side with the larger distance S and drive parallel, as Figure 4 shown.

Claims

1. A method for avoiding collisions by identifying the danger of a following vehicle based on energy loss, characterized in that, it includes: Collect the image information, driving speed and driving distance between the following vehicle and the own vehicle, and obtain the size information of the following vehicle according to the image information; Obtain the driving conditions of the lanes ahead and on both sides; Compare the size information of the following vehicle with the data in the vehicle type database to obtain the mass threshold, energy loss threshold and safe driving distance of the following vehicle; the vehicle type database stores the sizes, mass thresholds, energy loss thresholds and safe driving distances corresponding to different vehicle types; Estimate the energy loss of a collision between the following vehicle and the own vehicle according to the driving speed and mass threshold of the following vehicle and the driving speed and mass of the own vehicle. If the energy loss of the following vehicle is greater than the energy loss threshold and the driving distance between the following vehicle and the own vehicle is greater than the safe driving distance, it is considered risky, and a warning is given to the driver of the own vehicle and / or the following vehicle to remind the driver to take avoidance measures; if the energy loss of the following vehicle is greater than the energy loss threshold and the driving distance between the following vehicle and the own vehicle is less than the safe driving distance, it is considered risky, and the own vehicle is controlled to automatically take avoidance measures according to the driving conditions of the lanes ahead and on both sides.

2. The method for avoiding collisions by identifying the danger of a following vehicle based on energy loss according to claim 1, characterized in that, it further includes: Compare the driving speed of the following vehicle with the driving speed of the own vehicle, and compare the driving distance between the following vehicle and the own vehicle with the safe driving distance. If the driving speed of the following vehicle is greater than the driving speed of the own vehicle and the driving distance between the following vehicle and the own vehicle is greater than the safe driving distance, a warning is given to the driver of the own vehicle and / or the following vehicle to remind the driver to take avoidance measures.

3. The method for avoiding collisions by identifying the danger of a following vehicle based on energy loss according to claim 1, characterized in that, Compare the energy loss of the following vehicle with the energy loss threshold, and compare the driving distance between the following vehicle and the own vehicle with the safe driving distance to determine whether there is a risk. If there is a risk, avoidance measures are taken according to the driving conditions of the lanes ahead and on both sides, specifically including: If the energy loss of the following vehicle is greater than the energy loss threshold and the driving distance between the following vehicle and the own vehicle is greater than the safe driving distance, it is considered risky, and a warning is given to the driver of the following vehicle; If the energy loss of the following vehicle is greater than the energy loss threshold, the driving distance between the following vehicle and the own vehicle is less than the safe driving distance and greater than the preset critical safe driving distance, it is considered risky, and a warning is given to the driver of the own vehicle to remind the driver to take avoidance measures; the critical safe driving distance is pre-stored in the vehicle type database; If the energy loss of the following vehicle is greater than the energy loss threshold and the driving distance between the following vehicle and the own vehicle is less than the critical safe driving distance, it is considered risky, and the own vehicle is controlled to automatically take avoidance measures according to the driving conditions of the lanes ahead and on both sides.

4. The method for avoiding collisions by identifying the danger of a following vehicle based on energy loss according to claim 1, characterized in that, Controlling the own vehicle to automatically take avoidance measures according to the driving conditions of the lanes ahead and on both sides, specifically including: Judge whether the lane change condition is met according to the driving conditions of the two adjacent lanes. If the lane change condition is met, control the vehicle to change lanes automatically; if the lane change condition is not met, judge whether the accelerating escape lane change condition is met according to the driving conditions ahead. If the accelerating escape lane change condition is met, control the vehicle to accelerate automatically to the same speed as the vehicle behind. If the accelerating escape lane change condition is not met, control the vehicle to move closer to one of the adjacent lanes automatically according to the driving conditions of the two adjacent lanes to avoid the vehicle behind.

5. The avoidance method based on energy loss to identify the danger of the vehicle behind according to claim 4, characterized in that, obtain the driving conditions of the lanes ahead and on both sides. Specifically: collect the image information, driving speed, acceleration and driving distance between the vehicle and the host vehicle of the vehicle in the front side and the rear side, and collect the image information, driving speed and acceleration of the vehicle ahead to obtain the driving conditions of the lanes ahead and on both sides; Judge whether the lane change condition is met according to the driving conditions of the two adjacent lanes. Specifically: judge whether the following three conditions are met according to the driving conditions of the two adjacent lanes. If so, it is considered that the lane change condition is met; The distance between the host vehicle and the vehicle in the rear side satisfies: is the initial vehicle-to-vehicle distance between this vehicle and the vehicle behind at the side is the initial headway between the vehicle behind on the side-rear and the host vehicle; They are the driving speeds of the vehicle behind and the host vehicle respectively at the starting moment of lane change. are the accelerations of the vehicle behind and the host vehicle at time respectively; is the critical lane-changing time when this vehicle contacts the vehicle in the side and rear is the lane change completion time; is the vehicle body length; The distance between the host vehicle and the vehicle ahead satisfies: is the initial vehicle distance between the vehicle ahead in the original lane and the lane-changing vehicle; To switch to the dynamic vehicle distance between the vehicle and the vehicle ahead in the current lane; is the critical lane-changing time for the vehicle to contact the vehicle ahead; is the driving speed of the vehicle ahead at the starting moment of lane change; is the acceleration of the vehicle ahead at time ; The initial distance between the host vehicle and the vehicle in the front side satisfies: is the initial distance between the vehicle in front in the target lane and the lane-changing vehicle; is the dynamic vehicle distance between the lane-changing vehicle and the vehicle ahead in the target lane; is the critical lane-changing time when the vehicle contacts the vehicle in the front and on the side; is the driving speed of the vehicle in the side front at the starting moment of lane change; is the acceleration of the vehicle in the side front at time ​ 6. An avoidance system based on energy loss to identify the danger of the vehicle behind, characterized in that, comprising: an information collection module, a central control unit, and an execution module; The information collection module is used to collect the image information, driving speed and driving distance between the vehicle and the host vehicle of the vehicle behind, and obtain the driving conditions of the lanes ahead and on both sides; The central control unit is used to obtain the size information of the vehicle behind according to the image information of the vehicle behind; compare the size information of the vehicle behind with the data in the vehicle type database to obtain the mass threshold, energy loss threshold and safe driving distance of the vehicle behind; different vehicle sizes, mass thresholds, energy loss thresholds and safe driving distances are stored in the vehicle type database; estimate the energy loss of the collision between the vehicle behind and the host vehicle according to the driving speed and mass threshold of the vehicle behind and the driving speed and mass of the host vehicle. If the energy loss of the vehicle behind is greater than the energy loss threshold and the driving distance between the vehicle behind and the host vehicle is greater than the safe driving distance, it is considered risky, and a warning is given to the driver of the host vehicle and / or the vehicle behind to remind the driver to take avoidance measures; if the energy loss of the vehicle behind is greater than the energy loss threshold and the driving distance between the vehicle behind and the host vehicle is less than the safe driving distance, it is considered risky, and the host vehicle is controlled to take avoidance measures automatically according to the driving conditions of the lanes ahead and on both sides.

7. The avoidance system based on energy loss to identify the danger of the vehicle behind according to claim 6, characterized in that, the information collection module includes a millimeter wave radar and a camera; The millimeter wave radar includes a rear millimeter wave radar and side millimeter wave radars. The side millimeter wave radars include two front side millimeter wave radars and two rear side millimeter wave radars; the camera includes a front camera, a rear camera and two side cameras; The rear millimeter wave radar is used to collect the driving speed and the driving distance between the vehicle and the host vehicle of the vehicle behind. Side front millimeter-wave radar, used to collect the driving speed, acceleration of the vehicle in the side front and the driving distance from the vehicle itself; Side rear millimeter-wave radar, used to collect the driving speed, acceleration of the vehicle in the side rear and the driving distance from the vehicle itself; Rear camera, used to collect the image information of the vehicle behind; Front camera, used to collect the image information, driving speed, acceleration and lane line information of the vehicle in front; Side camera, used to collect the image information of the vehicle in the front side and the vehicle in the rear side; 8. The avoidance system for identifying the danger of the vehicle behind based on energy loss according to claim 6, characterized in that, the execution module includes a steering system and a motor gearbox; when the central control unit determines that there is a risk, it controls the steering system to perform a lane change operation according to the driving road conditions in the front, side front and side rear, or controls the motor gearbox to perform an acceleration operation.

9. The avoidance system for identifying the danger of the vehicle behind based on energy loss according to claim 8, characterized in that, the execution module includes a linear vibration motor installed on the steering wheel; when the central control unit determines that there is a risk, it controls the linear vibration motor to vibrate to remind the driver of the vehicle itself to take avoidance measures; and / or, the execution module includes a buzzer, when the central control unit determines that there is a risk, it controls the buzzer to beep to remind the driver of the vehicle itself to take avoidance measures.

Images