Automatic emergency braking control method for vehicle

Abstract

The invention discloses a vehicle automatic emergency braking control method, which relates to the technical field of vehicle emergency braking, and comprises the following steps: entering a vehicle capturing module, and carrying out vehicle data acquisition on a self vehicle and a front vehicle; and the vehicle enters the distance monitoring module, and the relative acceleration between the front vehicle and the own vehicle is calculated in real time through the collected vehicle data. In the distance monitoring module, the relative acceleration of the front vehicle and the own vehicle is calculated, the motion state between the two vehicles is reflected in real time, the future relative distance and relative speed of the front vehicle and the own vehicle are calculated, the collision risk is accurately recognized in advance, and the collision risk is accurately recognized based on the future relative distance and relative speed. Collision time at a future time point is calculated, risks are recognized in time, whether a user enters the motion monitoring module or not is judged, and driving safety is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle emergency braking, and particularly to a vehicle automatic emergency braking control method. Background Art

[0002] In scenarios with heavy traffic, or when the driver is distracted or the vehicle speed is high, the abnormal appearance of moving or stationary targets in front of the vehicle will pose a high collision risk. At this time, the automatic emergency braking system (AEB) will take over the vehicle in time and control the vehicle to achieve emergency braking with a large deceleration to avoid the occurrence of a collision or reduce the collision severity.

[0003] Currently, in the vehicle automatic emergency braking system, the collision risk is simply estimated based on the current vehicle speed and distance, without considering the factor of the vehicle's acceleration change, which will result in a large deviation. At the same time, during the braking process, the driver's autonomous braking and avoidance are not considered, resulting in frequent false triggers, that is, the driver has taken appropriate measures to avoid a collision, but the system still activates the braking, which will make the driver doubt the reliability of the system and reduce the trust in the system.

[0004] Therefore, a vehicle automatic emergency braking control method is proposed to solve the above problems. Summary of the Invention

[0005] The main object of the present invention is to provide a vehicle automatic emergency braking control method to solve the problems raised in the above background.

[0006] To achieve the above object, the technical solution adopted by the present invention is: a vehicle automatic emergency braking control method, including the following steps:

[0007] Step 1: Enter the vehicle capture module to collect vehicle data of the own vehicle and the vehicle in front.

[0008] Step 2: Enter the distance monitoring module, and through the collected vehicle data, calculate the relative acceleration between the vehicle in front and the own vehicle in real time, calculate the future relative speed and future relative distance, then calculate the collision time between the future vehicle in front and the own vehicle, and by comparing whether the collision time exceeds the set time threshold, if it exceeds or is equal to the set time threshold, enter the motion monitoring module, if it does not exceed the set time threshold, continue to drive normally;

[0009] Step 3: Enter the motion monitoring module, calculate the lateral motion data of the vehicle through the vehicle data collected in real time, determine whether the vehicle is in a lateral avoidance operation by comparing the lateral motion data, calculate the braking pedal force, and determine whether it is in manual braking by comparing the braking pedal force. If it is in a lateral avoidance operation or manual braking, do not enter the emergency braking module. If it is not in a lateral avoidance operation and manual braking, enter the emergency braking module;

[0010] Step 4: Enter the emergency braking module, compare the time to collision with the set braking levels, perform vehicle braking at the corresponding braking level based on the comparison result, and determine whether to perform an emergency avoidance or emergency braking according to the avoidance space.

[0011] Further, the vehicle capture module includes a capture unit and a storage unit;

[0012] The capture unit is used to collect vehicle data of its own vehicle and the vehicle ahead in real time through a radar sensor, an acceleration sensor, a steering angle sensor, and a pedal sensor;

[0013] The storage unit is used to receive and store the vehicle data of its own vehicle and the vehicle ahead collected in real time through in-vehicle memory.

[0014] Further, the distance monitoring module includes an acceleration unit, a future speed unit, a future distance unit, and a comparison unit;

[0015] The acceleration unit calculates the relative acceleration based on the vehicle data of its own vehicle and the vehicle ahead collected in real time. The calculation formula is as follows:

[0016] a rel =a target -a self ;

[0017] Wherein, a rel represents the relative acceleration, a target represents the acceleration of the vehicle ahead, and a self represents the acceleration of its own vehicle.

[0018] Further, the future speed unit is used to predict the relative speed of its own vehicle and the vehicle ahead at a future moment. The calculation formula is as follows:

[0019] u rel (t)=u rel (t0)+a rel ·Δt;

[0020] Wherein, a rel represents the relative acceleration, u rel (t0) represents the relative speed at the current moment, Δt represents the time interval, urel (t) represents the relative speed at the future time t.

[0021] Furthermore, the future distance unit is used to predict the relative distance between the vehicle itself and the vehicle ahead at a future time, and the calculation formula is as follows:

[0022]

[0023] Wherein, d(t) represents the relative distance at the future time t, d(t0) represents the relative distance at the current time, and u rel (t0) represents the relative speed at the current time, and a rel represents the relative acceleration, and Δt represents the time interval.

[0024] Furthermore, the comparison unit is used to calculate and compare the collision time between the vehicle itself and the vehicle ahead at a future time, and the calculation formula is as follows:

[0025]

[0026] Wherein, TTC(t) represents the collision time at the future time point t, d(t) represents the relative distance at the future time t, and u rel (t) represents the relative speed at the future time t;

[0027] Wherein, a time threshold is set for TTC(t). When TTC(t) is greater than or equal to 3 seconds, the vehicle travels normally. When TTC(t) is less than 3 seconds, it enters the motion monitoring module.

[0028] Furthermore, the motion monitoring module includes an avoidance unit and an autonomous unit.

[0029] Furthermore, the avoidance unit includes a motion unit and a trigger unit I;

[0030] The motion unit is used to calculate the lateral acceleration of the vehicle based on the vehicle data collected, and the calculation formula is as follows:

[0031]

[0032] Wherein, a y represents the lateral acceleration of the vehicle, θ represents the vehicle steering angle, t represents time, d represents the differential symbol, dθ represents the change in the steering angle θ, and dt represents the change in time t;

[0033] The trigger unit I is used to receive the lateral acceleration of the vehicle in real time and compare the absolute value of a y with the set speed threshold. The speed threshold of the lateral acceleration is set to 2 m / s, that is, |a yWhen it is greater than or equal to 2 m / s, it means that the vehicle itself makes a lateral avoidance and does not enter the emergency braking module. If y When it is less than 2 m / s, it means that the vehicle does not make a lateral avoidance and then enters the emergency braking module.

[0034] Furthermore, the automatic unit includes a calculation unit and a trigger unit II;

[0035] The calculation unit is used to calculate the change rate of the driver's brake pedal force, and the calculation formula is as follows:

[0036]

[0037] Among them, ΔQ represents the change rate of the brake pedal stepping force, Q represents the brake pedal stepping force, and dt represents the time change amount;

[0038] The trigger unit II is used to compare the change rate of the brake pedal stepping force received in real time with the set force threshold. The force threshold of the brake pedal stepping force is 50 N. That is, when ΔQ is greater than or equal to 50 N, it means that it is in manual braking and does not enter the emergency braking module. When ΔQ is less than 50 N, it means that it is not in manual braking and then enters the emergency braking module.

[0039] Furthermore, the emergency braking module includes a level unit and an execution unit;

[0040] The emergency braking module includes a level unit and an execution unit;

[0041] The level unit sets the braking level based on the time to collision TTC(t) at the future time point t;

[0042] When TTC(t) is greater than 0 s and TTC(t) is less than or equal to 1 s, it means an emergency situation. Determine whether to avoid by steering. The calculation formula is as follows:

[0043]

[0044] Among them, u represents the current speed of the vehicle, a y The lateral acceleration of the vehicle, R min represents the minimum turning radius. When R min is greater than the available space, the vehicle performs an emergency avoidance operation; when R min is less than or equal to the available space, the emergency avoidance operation cannot be performed, and emergency braking is triggered. The threshold of the available space is set to 0.5 m;

[0045] When TTC(t) is greater than 1 s and TTC(t) is less than or equal to 2 s, it means a relatively high risk, and high-level braking is taken;

[0046] When TTC(t) is greater than 2 s and less than or equal to 3 s, it represents a risky situation and low-level braking is taken.

[0047] The execution unit performs emergency braking on its own vehicle based on the braking level of the level unit.

[0048] The present invention has the following beneficial effects:

[0049] 1. In the distance monitoring module of the present invention, by calculating the relative acceleration between the vehicle ahead and its own vehicle, the motion state between the two vehicles is reflected in real time, and the future relative distance and relative speed between the vehicle ahead and its own vehicle are calculated. The collision risk is accurately identified in advance, and based on the future relative distance and relative speed, the time to collision at a future time point is calculated, and the risk is timely identified and it is determined whether to enter the motion monitoring module, improving driving safety.

[0050] 2. In the motion monitoring module of the present invention, by calculating the lateral acceleration of the vehicle, the avoidance intention of its own vehicle is captured and compared with the set lateral acceleration threshold to determine whether the vehicle is in a lateral avoidance operation. By calculating the change rate of the driver's brake pedal force, the braking intention of the driver is reflected in real time and compared with the set brake pedal force threshold to determine whether the driver is in manual braking. During the determination process, if in a lateral avoidance operation or manual braking, it does not enter the emergency braking module. If not in a lateral avoidance operation and manual braking, it enters the emergency braking module. By judging the lateral acceleration and the driver's braking intention, the probability of the system accidentally triggering emergency braking is significantly reduced, ensuring the accuracy and reliability of the system.

[0051] 3. In the emergency braking module of the present invention, by setting the braking level and taking different braking levels according to different calculated time-to-collision values in the comparison unit, low-level braking can be taken when the risk is low, avoiding the discomfort caused by sudden braking. In an emergency, the highest braking is triggered in a timely manner, reducing the collision risk and reducing unnecessary sudden braking, enabling the most appropriate braking measures to be taken in different situations, and improving the safety, reliability and driving experience of the vehicle's automatic emergency braking system. Description of the Drawings

[0052] Figure 1 is a flowchart of a vehicle automatic emergency braking control method of the present invention;

[0053] Figure 2 is a schematic diagram of the process architecture of a vehicle automatic emergency braking control method of the present invention;

[0054] Figure 3 is a flowchart of the vehicle capture module of a vehicle automatic emergency braking control method of the present invention;

[0055] Figure 4 Flow chart of the distance monitoring module for an automatic emergency braking control method of a vehicle according to the present invention;

[0056] Figure 5 Flow chart of the motion monitoring module for an automatic emergency braking control method of a vehicle according to the present invention. Specific embodiments

[0057] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0058] Embodiment 1

[0059] Please refer to Figure 1 、 Figure 2 、 Figure 3 and Figure 4 The present invention provides a technical solution: an automatic emergency braking control method for a vehicle, including the following steps:

[0060] Step 1: Enter the vehicle capture module to collect vehicle data of the own vehicle and the vehicle ahead;

[0061] Step 2: Enter the distance monitoring module, and based on the collected vehicle data, calculate the relative acceleration between the vehicle ahead and the own vehicle in real time, calculate the future relative speed and future relative distance, then calculate the collision time between the future vehicle ahead and the own vehicle, and by comparing whether the collision time exceeds the set time threshold. If it exceeds or is equal to the set time threshold, enter the motion monitoring module; if it does not exceed the set time threshold, continue to drive normally;

[0062] Step 3: Enter the motion monitoring module, calculate the lateral motion data of the vehicle through the real-time collected vehicle data, determine whether the vehicle is in a lateral avoidance operation by comparing the lateral motion data, calculate the braking pedal depression force, and determine whether it is in a manual braking by comparing the braking pedal depression force. If it is in a lateral avoidance operation or manual braking, do not enter the emergency braking module; if it is not in a lateral avoidance operation and manual braking, enter the emergency braking module;

[0063] Step 4: Enter the emergency braking module, compare the future collision time with the set braking levels, and perform vehicle braking at the corresponding braking levels based on the comparison result, and determine whether to perform an emergency avoidance or emergency braking according to the avoidance space.

[0064] The vehicle capture module includes a capture unit and a storage unit;

[0065] The capture unit is used to collect vehicle data of its own vehicle and the vehicle ahead in real time through a radar sensor, an acceleration sensor, a steering angle sensor, and a pedal sensor;

[0066] The storage unit is used to receive and store the vehicle data of its own vehicle and the vehicle ahead collected in real time through in-vehicle memory.

[0067] The distance monitoring module includes an acceleration unit, a future speed unit, a future distance unit, and a comparison unit;

[0068] The acceleration unit calculates the relative acceleration based on the vehicle data of its own vehicle and the vehicle ahead collected in real time. The calculation formula is as follows:

[0069] a rel = a target - a self ;

[0070] Where a rel represents the relative acceleration, a target represents the acceleration of the vehicle ahead, and a self represents the acceleration of its own vehicle.

[0071] The future speed unit is used to predict the relative speed of its own vehicle and the vehicle ahead at a future moment. The calculation formula is as follows:

[0072] u rel (t)= u rel (t0)+ a rel ·Δt;

[0073] Where a rel represents the relative acceleration, u rel (t0) represents the relative speed at the current moment, Δt represents the time interval, and u rel (t) represents the relative speed at a future time t.

[0074] The future distance unit is used to predict the relative distance of its own vehicle and the vehicle ahead at a future moment. The calculation formula is as follows:

[0075]

[0076] Where d(t) represents the relative distance at a future time t, d(t0) represents the relative distance at the current moment, u rel (t0) represents the relative speed at the current moment, a rel represents the relative acceleration, and Δt represents the time interval.

[0077] The comparison unit is used to calculate and compare the collision time of its own vehicle and the vehicle ahead at a future moment. The calculation formula is as follows:

[0078]

[0079] Among them, TTC(t) represents the time to collision at future time point t, d(t) represents the relative distance at future time t, and u rel (t) represents the relative speed at future time t;

[0080] Among them, a time threshold is set for TTC(t). When TTC(t) is greater than or equal to 3 seconds, normal driving is performed. When TTC(t) is less than 3 seconds, it enters the motion monitoring module.

[0081] Among them, vehicle data may include the distance between the vehicle itself and the vehicle in front, the acceleration a of the vehicle itself self , the acceleration a of the vehicle in front target , the steering angle θ of the steering wheel of the vehicle itself, and the depression force Q of the pedal. Specifically, the distance between the vehicle itself and the vehicle in front is collected in real time through a radar sensor. The acceleration a of the vehicle itself is collected in real time through an acceleration sensor self , the acceleration a of the vehicle in front target . The steering angle of the steering wheel of the vehicle itself is collected in real time through a steering angle sensor, and the depression force of the pedal is collected in real time through a pedal sensor.

[0082] In this embodiment, in the vehicle capture module, the steering angle of the steering wheel of the vehicle itself, the depression force of the pedal, the acceleration of the vehicle itself, and the distance from the vehicle in front, and the acceleration of the vehicle in front are collected in real time through a radar sensor, an acceleration sensor, a steering angle sensor, and a pedal sensor. Vehicle data is obtained from multiple dimensions. At the same time, the in-vehicle memory receives and stores the collected vehicle data to ensure the integrity of the data, providing stable data support for subsequent judgments. In the distance monitoring module, by calculating the relative acceleration between the vehicle in front and the vehicle itself, the motion state between the two vehicles is reflected in real time, and the future relative distance and relative speed between the vehicle in front and the vehicle itself are calculated to accurately identify the collision risk in advance. Based on the future relative distance and relative speed, the time to collision at the future time point is calculated to timely identify the risk and determine whether to enter the motion monitoring module, improving driving safety.

[0083] Embodiment 2

[0084] Please refer to Figure 1 , Figure 2 and Figure 5 , the present invention provides a technical solution: based on Embodiment 1,

[0085] The motion monitoring module includes an avoidance unit and an autonomous unit.

[0086] The avoidance unit includes a motion unit and a trigger unit I;

[0087] The motion unit is used to collect vehicle data to calculate the vehicle lateral acceleration. The calculation formula is as follows:

[0088]

[0089] Among them, a y represents the lateral acceleration of the vehicle, θ represents the steering angle of the vehicle, t represents time, d represents the differential sign, dθ represents the change in the steering angle θ, and dt represents the change in time t;

[0090] The trigger unit 1 is used to receive the lateral acceleration of the vehicle in real time and obtain a y The absolute value of is compared with the set speed threshold. The speed threshold of lateral acceleration is set to 2m / s, that is, |a y |When it is greater than or equal to 2m / s, it means that the vehicle is making a lateral avoidance and does not enter the emergency braking module. y |When it is less than 2m / s, it means that the vehicle does not perform lateral avoidance and enters the emergency braking module.

[0091] The automatic unit includes a calculation unit and a trigger unit 2;

[0092] The calculation unit is used to calculate the change rate of the driver's brake pedal force. The calculation formula is as follows:

[0093]

[0094] Where ΔQ represents the rate of change of the brake pedal force, Q represents the brake pedal force, and dt represents the time change;

[0095] Trigger unit 2 is used to receive the change rate of the brake pedal force in real time and compare it with the set force threshold. The force threshold of the brake pedal force is 50N, that is, when ΔQ is greater than or equal to 50N, it means that it is in manual braking and does not enter the emergency braking module. When ΔQ is less than 50N, it means that it is not in manual braking and enters the emergency braking module.

[0096] It should be noted that the motion monitoring module is used to determine whether emergency braking is required in an emergency situation. Specifically, when it is determined that the vehicle is in a lateral avoidance operation, it is considered that the vehicle can avoid the vehicle in front by changing the direction of travel, so there is no need to perform emergency braking. When it is determined that manual braking is in progress, it is considered that the driver avoids the vehicle in front by braking and slowing down, so there is no need to perform emergency braking. When it is determined that the vehicle is not in a lateral avoidance operation and is not in manual braking, it is considered that the vehicle is not controlled to perform any avoidance action. At this time, it is considered that emergency braking is required.

[0097] In this embodiment, in the motion monitoring module, by calculating the lateral acceleration of the vehicle, the avoidance intention of the host vehicle is captured and compared with the set lateral acceleration threshold to determine whether the vehicle is in a lateral avoidance operation. By calculating the change rate of the driver's brake pedal force, the braking intention of the driver is reflected in real time and compared with the set brake pedal force threshold to determine whether the driver is in manual braking. During the judgment process, if in a lateral avoidance operation or manual braking, it does not enter the emergency braking module. If not in a lateral avoidance operation and manual braking, it enters the emergency braking module. By judging the lateral acceleration and the driver's braking intention, the probability of the system accidentally triggering emergency braking is significantly reduced, ensuring the accuracy and reliability of the system.

[0098] Embodiment Three

[0099] Please refer to Figure 1 and Figure 2 , the present invention provides a technical solution: based on Embodiment One,

[0100] The emergency braking module includes a level unit and an execution unit. The level unit sets the braking level based on the time to collision;

[0101] Based on the explanation of the foregoing embodiments, in this embodiment, the basis for the level unit to set the braking level based on the time to collision TTC(t) at the future time point t is as follows:

[0102] When TTC(t) is greater than 0 s and TTC(t) is less than or equal to 1 s, it represents an emergency situation. Determine whether to avoid by steering. The calculation formula is as follows:

[0103]

[0104] where u represents the current speed of the vehicle, a y the lateral acceleration of the vehicle, R min represents the minimum turning radius. When R min is greater than the available space, the vehicle performs an emergency avoidance operation; when R min is less than or equal to the available space, the emergency avoidance operation cannot be performed, and emergency braking is triggered. The threshold of the available space is set to 0.5 m;

[0105] When TTC(t) is greater than 1 s and TTC(t) is less than or equal to 2 s, it represents a high risk, and medium braking is taken;

[0106] When TTC(t) is greater than 2 s and TTC(t) is less than or equal to 3 s, it represents a risky situation, and low braking is taken;

[0107] The execution unit performs the emergency braking of the host vehicle based on the braking level of the level unit.

[0108] Specifically, the braking level can be determined by a set of multiple future collision time ranges. That is to say, multiple future collision time ranges can be set, and a corresponding number of braking levels can be set based on the multiple future collision time ranges. In this way, when it is compared and found that the future collision time falls within a certain future collision time range, the braking level corresponding to that future collision time range is executed.

[0109] For ease of understanding, an exemplary description is given below.

[0110] Suppose the first future collision time range corresponds to the first braking level, the second future collision time range corresponds to the second braking level, and the third future collision time range corresponds to the third braking level. When the values within the first future collision time range, the second future collision time range, and the third future collision time range increase in sequence, the braking urgency of the first braking level, the second braking level, and the third braking level decreases in sequence.

[0111] At this time, if the future collision time falls within the first future collision time range, an attempt will be made to steer and avoid first because steering operations are usually faster and more effective than braking operations. If steering is not feasible, the system will immediately trigger emergency braking to minimize the collision risk, and the vehicle will execute the first braking level, with the vehicle braking rapidly. If the future collision time falls within the second future collision time range, the vehicle will execute the second braking level, with the vehicle braking at medium speed. If the future collision time falls within the third future collision time range, the vehicle will execute the third braking level, with the vehicle braking at low speed.

[0112] In this embodiment, in the emergency braking module, by setting the braking level and taking different braking levels according to the different collision time values calculated in the comparison unit, it is possible to take a low-level braking when the risk is low, avoiding the discomfort caused by sudden braking. In an emergency, by comparing the minimum turning radius with the available space, it is judged whether it is possible to attempt to steer and avoid. By steering, a frontal collision can be converted into a side collision, reducing the severity of the collision. If steering is not feasible, the system will immediately trigger emergency braking to minimize the collision risk, reducing unnecessary sudden braking, so that the most appropriate braking measures can be taken in different situations, improving the safety, reliability, and driving experience of the vehicle's automatic emergency braking system.

[0113] Among them, the braking level, the force threshold, and the speed threshold are all determined by collecting a large amount of vehicle driving data during actual road tests or test site tests, observing the driving state, handling performance, and safety performance of the vehicle under different lateral accelerations and braking pedal force change rates, and through statistical analysis of these data, combined with engineering experience and safety standards, finally determining the appropriate level and threshold.

[0114] In the present invention, a method for controlling automatic emergency braking of a vehicle:

[0115] In the vehicle capture module, the steering angle of the steering wheel of the vehicle itself, the stepping force of the pedal, the acceleration of the vehicle itself, the distance from the vehicle in front, and the acceleration of the vehicle in front are collected in real time through a radar sensor, an acceleration sensor, a steering angle sensor, and a pedal sensor. Vehicle data is obtained from multiple dimensions. At the same time, the in-vehicle memory receives and stores the collected vehicle data to ensure the integrity of the data, providing stable data support for subsequent judgments.

[0116] In the distance monitoring module, by calculating the relative acceleration between the vehicle in front and the vehicle itself, the motion state between the two vehicles is reflected in real time, and the future relative distance and relative speed between the vehicle in front and the vehicle itself are calculated. The collision risk is accurately identified in advance, and based on the future relative distance and relative speed, the time to collision at a future time point is calculated to timely identify the risk and determine whether to enter the motion monitoring module, improving driving safety.

[0117] In the motion monitoring module, by calculating the lateral acceleration of the vehicle, the avoidance intention of the vehicle itself is captured and compared with a set lateral acceleration threshold to determine whether the vehicle is in a lateral avoidance operation. By calculating the change rate of the driver's brake pedal force, the braking intention of the driver is reflected in real time and compared with a set brake pedal force threshold to determine whether the driver is in a manual braking state. During the judgment process, if in a lateral avoidance operation or manual braking, it does not enter the emergency braking module. If not in a lateral avoidance operation and manual braking, it enters the emergency braking module. By judging the lateral acceleration and the driver's braking intention, the probability of the system mis-triggering emergency braking is significantly reduced, ensuring the accuracy and reliability of the system.

[0118] In the emergency braking module, by setting the braking level and taking different braking levels according to different time-to-collision values calculated in the comparison unit, it is possible to take a low-level braking when the risk is low, avoiding the discomfort caused by sudden braking, triggering the highest braking in a timely manner in an emergency, reducing the collision risk, reducing unnecessary sudden braking, and enabling the most appropriate braking measures to be taken in different situations, improving the safety, reliability, and driving experience of the vehicle automatic emergency braking system.

[0119] It should be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device.

[0120] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A vehicle automatic emergency braking control method, characterized in that: The following steps are involved: Step 1: Enter the vehicle capture module and collect vehicle data for the vehicle itself and the vehicle in front; Step 2: Enter the distance monitoring module, and use the collected vehicle data to calculate the relative acceleration between the front vehicle and the own vehicle in real time, and calculate the future relative speed and future relative distance, and then calculate the collision time between the front vehicle and the own vehicle in the future, and compare whether the collision time exceeds the set time threshold. If it exceeds or equals the set time threshold, enter the motion monitoring module, if it does not exceed the set time threshold, continue to drive normally; Step 3: Enter the motion monitoring module, and calculate the lateral motion data of the vehicle through the real-time collected vehicle data, judge whether the vehicle is in a lateral avoidance operation by comparing the lateral motion data, and calculate the brake pedal stepping force, and judge whether it is in manual braking by comparing the brake pedal stepping force. If it is in a lateral avoidance operation or manual braking, do not enter the emergency braking module, if it is not in a lateral avoidance operation and manual braking, enter the emergency braking module; Step 4: Enter the emergency braking module, compare the future collision time with the set braking level, and brake the vehicle at the corresponding braking level based on the comparison result, and determine whether to perform emergency avoidance or emergency braking based on the avoidance space.

2. A vehicle automatic emergency braking control method according to claim 1, characterized in that: The vehicle capture module includes a capture unit and a storage unit; The capture unit is used to collect vehicle data of the own vehicle and the vehicle in front in real time through a radar sensor, an acceleration sensor, a steering angle sensor and a pedal sensor; The storage unit is used to receive and store the vehicle data of the own vehicle and the vehicle in front collected in real time through the vehicle-mounted memory.

3. A vehicle automatic emergency braking control method according to claim 1, characterized in that: The distance monitoring module includes an acceleration unit, a future speed unit, a future distance unit and a comparison unit; The acceleration unit calculates the relative acceleration based on the real-time acquisition of vehicle data of the own vehicle and the vehicle in front, and the calculation formula is as follows: a rel =a target -a self ; Among them, a rel represents the relative acceleration, a target represents the acceleration of the vehicle ahead, a self Represents the vehicle's acceleration.

4. A vehicle automatic emergency braking control method according to claim 3, characterized in that: The future speed unit is used to predict the relative speed between the own vehicle and the vehicle ahead at a future moment, and the calculation formula is as follows: u rel (t)=u rel (t0)+a rel ·Δt; Among them, a rel represents the relative acceleration, u rel (t0) represents the relative speed at the current moment, Δt represents the time interval, and u rel (t) represents the relative speed at time t in the future.

5. A vehicle automatic emergency braking control method according to claim 4, characterized in that: The future distance unit is used to predict the relative distance between the own vehicle and the vehicle in front at the future moment, and the calculation formula is as follows: Among them, d(t) represents the relative distance at time t in the future, d(t0) represents the relative distance at the current time, and u rel (t0) represents the relative speed at the current moment, a rel represents the relative acceleration, and Δt represents the time interval.

6. A vehicle automatic emergency braking control method according to claim 5, characterized in that: The comparison unit is used to calculate and compare the collision time between the own vehicle and the vehicle in front at a future moment, and the calculation formula is as follows: Among them, TTC(t) represents the collision time at the future time point t, d(t) represents the relative distance at the future time point t, and u rel (t) represents the relative speed at time t in the future; Among them, a time threshold is set for TTC(t). When TTC(t) is greater than or equal to 3 seconds, normal driving is performed. When TTC(t) is less than 3 seconds, the vehicle enters the motion monitoring module.

7. A vehicle automatic emergency braking control method according to claim 1, characterized in that: The motion monitoring module includes an avoidance unit and an autonomous unit.

8. A vehicle automatic emergency braking control method according to claim 7, characterized in that: The avoidance unit includes a motion unit and a trigger unit 1; The motion unit is used to calculate the vehicle lateral acceleration using the collected vehicle data. The calculation formula is as follows: Where ax represents the lateral acceleration of the vehicle, θ represents the steering angle of the vehicle, t represents time, d represents the differential sign, dθ represents the change in the steering angle θ, and dt represents the change in time t; The trigger unit 1 is used to receive the lateral acceleration of the vehicle in real time and obtain a y The absolute value of the lateral acceleration is compared with the set speed threshold, and the speed threshold of the lateral acceleration is set to 2m / s, that is, |a y |When it is greater than or equal to 2m / s, it means that the vehicle is making a lateral avoidance and does not enter the emergency braking module. y |When it is less than 2m / s, it means that the vehicle does not perform lateral avoidance and enters the emergency braking module.

9. The vehicle automatic emergency braking control method according to claim 7, characterized in that: The automatic unit includes a calculation unit and a trigger unit 2; The calculation unit is used to calculate the change rate of the driver's brake pedal force, and the calculation formula is as follows: Where ΔQ represents the rate of change of the brake pedal force, Q represents the brake pedal force, and dt represents the time change; The trigger unit 2 is used to receive the change rate of the brake pedal stepping force in real time and compare it with the set force threshold. The force threshold of the brake pedal stepping force is 50N, that is, when ΔQ is greater than or equal to 50N, it means that it is in manual braking and does not enter the emergency braking module. When ΔQ is less than 50N, it means that it is not in manual braking and enters the emergency braking module.

10. The vehicle automatic emergency braking control method according to claim 1, characterized in that: The emergency brake module includes a level unit and an execution unit; The level unit sets the braking level based on the collision time TTC(t) at the future time point t; When TTC(t) is greater than 0s and TTC(t) is less than or equal to 1s, it indicates an emergency situation and whether to avoid the vehicle by steering is determined by the following calculation formula: Among them, u represents the current speed of the vehicle, a y The lateral acceleration of the vehicle, R min Represents the minimum turning radius, when R min When R is larger than the available space, the vehicle performs an emergency avoidance maneuver; min When the available space is less than or equal to the available space, emergency avoidance maneuvers cannot be performed and emergency braking is triggered. The threshold of available space is set to 0.5m. When TTC(t) is greater than 1s and TTC(t) is less than or equal to 2s, it means there is a high risk and high-level braking is adopted; When TTC(t) is greater than 2s and TTC(t) is less than or equal to 3s, it indicates a risky situation and low-level braking is adopted; The execution unit executes emergency braking of the host vehicle based on the braking level of the level unit.

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