Intelligent network connection passenger car slippery road AEB control system and method

Abstract

The application discloses a kind of intelligent network connection passenger car wet and slippery road AEB control system and method, comprising: whole vehicle controller and respectively with whole vehicle controller connection wheel speed acquisition unit, motor controller, image acquisition unit and AEB system;Wheel speed acquisition unit is installed on the hub of wheel, for collecting the wheel speed of left and right rear wheels of vehicle;Motor controller is used to output motor speed;Image acquisition unit is used to obtain the distance and relative speed of front obstacle;Whole vehicle controller receives the data obtained by wheel speed acquisition unit, motor controller, image acquisition unit and utilizes the data obtained to calculate current vehicle speed, whole vehicle slip rate and collision time respectively, and the calculation result is output to AEB system;AEB system determines different deceleration according to the current vehicle speed, whole vehicle slip rate and collision time.Solve the current intelligent network connection passenger car in wet and slippery road AEB trigger vehicle easy to spin problem, reduce the risk of vehicle spin, improve the safety of whole vehicle.

Description

Technical Field

[0001] This invention relates to the field of vehicle automatic emergency braking function control technology, and in particular to an intelligent connected bus AEB control system and method for slippery road surfaces. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] With the rapid development of intelligent technologies, the global market for intelligent connected vehicles has shown rapid growth. Automatic Emergency Braking (AEB) systems can effectively reduce collisions, promoting the widespread application and development of AEB technology in the intelligent connected bus industry. However, emergency braking on slippery roads can easily cause rear wheel lock-up, leading to vehicle skidding and traffic accidents. How to reasonably trigger the emergency braking system on low-friction surfaces has become one of the key technologies in current research on intelligent connected vehicles. Most publicly available research on AEB systems determines deceleration based on the collision time between the vehicle and an obstacle, requesting the braking system to slow down. This method does not consider the actual road conditions, and on slippery roads, excessive deceleration can easily lead to vehicle skidding. Summary of the Invention

[0004] To address the aforementioned issues, this invention proposes an AEB (Automatic Emergency Braking) control system and method for intelligent connected buses on slippery roads. By combining the vehicle's slip ratio, speed, and collision time with obstacles, the system calculates the emergency braking deceleration of the vehicle under different road conditions and formulates different AEB exit control methods. This solves the problem of current intelligent connected buses easily fishtailing when AEB is triggered on slippery roads, reduces the risk of fishtailing, and improves overall vehicle safety.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] In a first aspect, the present invention provides an intelligent connected bus AEB control system for slippery road surfaces, comprising: a vehicle controller and a wheel speed acquisition unit, a motor controller, an image acquisition unit and an AEB system respectively connected to the vehicle controller;

[0007] The wheel speed acquisition unit is mounted on the wheel hub and is used to acquire the wheel speeds of the left and right rear wheels of the vehicle; the motor controller is used to output the motor speed; the image acquisition unit is used to acquire the distance and relative speed to obstacles in front.

[0008] The vehicle controller receives data from the wheel speed acquisition unit, motor controller, and image acquisition unit, and uses the acquired data to calculate the current vehicle speed, vehicle slip ratio, and collision time, and outputs the calculation results to the AEB system.

[0009] The AEB system determines different decelerations based on the current vehicle speed, vehicle slip ratio, and collision time.

[0010] Preferably, after the vehicle's AEB is triggered, the AEB system formulates different AEB exit methods based on the vehicle speed and the overall vehicle slip ratio.

[0011] Preferably, when collecting data, the vehicle controller receives information from the wheel speed acquisition unit, motor controller, and image acquisition unit via CAN messages.

[0012] Secondly, the present invention provides an AEB control method for intelligent connected buses on slippery roads, including: collecting vehicle motor speed, left and right rear wheel speeds, and distance and relative speed to obstacles in front;

[0013] The current vehicle speed is calculated using the motor speed, and the overall vehicle slip ratio is calculated based on the wheel speeds of the left and right rear wheels and the current vehicle speed.

[0014] Calculate the collision time with the obstacle using the obtained distance and relative velocity;

[0015] Different deceleration rates are determined based on the vehicle slip ratio, current vehicle speed, and collision time.

[0016] Preferably, the left rear wheel slip ratio is calculated based on the left rear wheel speed and the current vehicle speed:

[0017] If the vehicle speed is equal to 0, or less than or equal to the speed of the left rear wheel, then the slip ratio of the left rear wheel is 0.

[0018] If the vehicle speed is greater than 0 and greater than the speed of the left rear wheel, the formula for calculating the slip ratio of the left rear wheel is as follows:

[0019] Where v1 is the left rear wheel speed, v is the current vehicle speed, and w1 is the left rear wheel slip ratio;

[0020] Calculate the right rear wheel slip ratio based on the right rear wheel speed and the current vehicle speed:

[0021] If the vehicle speed is equal to 0, or less than or equal to the right rear wheel speed, then the right rear wheel slip ratio is 0.

[0022] If the vehicle speed is greater than 0 and greater than the speed of the right rear wheel, the formula for calculating the slip ratio of the right rear wheel is as follows:

[0023] Where v2 is the left rear wheel speed, v is the current vehicle speed, and w2 is the left rear wheel slip ratio;

[0024] The overall vehicle slip ratio is the maximum of the slip ratios of the left rear wheel and the right rear wheel.

[0025] Preferably, the distance to the obstacle in front includes both longitudinal and lateral distances. The collision time with the obstacle is calculated using the longitudinal and lateral distances and the relative velocity. The specific method is as follows:

[0026] If the lateral distance X is greater than the preset distance, there is no risk of collision between the vehicle and the obstacle, and the collision time is infinite.

[0027] If the lateral distance X is less than or equal to the preset distance and the relative velocity is greater than or equal to 0, the collision time is infinite.

[0028] If the lateral distance X is less than or equal to the preset distance and the relative velocity is less than 0, the collision time is determined according to the following formula:

[0029]

[0030] Where ttc is the collision time, Y is the longitudinal distance, and Δv is the relative velocity.

[0031] Preferably, different decelerations are determined based on the vehicle slip ratio, current vehicle speed, and collision time. The specific method is as follows:

[0032] When the vehicle speed is greater than the first speed, the slip ratio reference values ​​are set as the first reference value and the second reference value, respectively.

[0033] If the vehicle slip ratio is less than the first reference value, then the collision time is compared. If the collision time is greater than the sixth preset time, the deceleration is equal to 0; if the collision time is greater than the first preset time and less than or equal to the sixth preset time, the deceleration is equal to the seventh preset value; if the collision time is less than or equal to the first preset time, the deceleration is equal to the ninth preset value.

[0034] If the vehicle slip ratio is greater than or equal to the first reference value and less than the second reference value, then the collision time is compared. If the collision time is greater than the eighth preset time, the deceleration is equal to 0; if the collision time is greater than the fifth preset time and less than or equal to the eighth preset time, the deceleration is equal to the fifth preset value; if the collision time is less than or equal to the second preset time, the deceleration is equal to the eighth preset value.

[0035] If the vehicle slip ratio is greater than or equal to the second benchmark value, then the collision time is compared. If the collision time is greater than the ninth preset time, the deceleration is equal to 0; if the collision time is less than or equal to the ninth preset time, the deceleration is equal to the fifth preset value.

[0036] Preferably, different decelerations are determined based on the vehicle slip ratio, current vehicle speed, and collision time. The specific method is as follows:

[0037] When the vehicle speed is less than or equal to the first speed and greater than the second speed, the slip ratio reference values ​​are set as the third and fourth reference values, respectively.

[0038] If the vehicle slip ratio is less than the third benchmark value, then the collision time is compared. If the collision time is greater than the fifth preset time, the deceleration is equal to 0; if the collision time is greater than the first preset time and less than or equal to the fifth preset time, the deceleration is equal to the fifth preset value; if the collision time is less than or equal to the first preset time, the deceleration is equal to the eighth preset value.

[0039] If the vehicle slip ratio is greater than or equal to the third benchmark value and less than the fourth benchmark value, then the collision time is compared. If the collision time is greater than the sixth preset time, the deceleration is equal to 0; if the collision time is greater than the third preset time and less than or equal to the sixth preset time, the deceleration is equal to the second preset value; if the collision time is less than or equal to the third preset time, the deceleration is equal to the fifth preset value.

[0040] If the vehicle slip ratio is greater than or equal to the fourth baseline value, then the collision time is compared. If the collision time is greater than the seventh preset time, the deceleration is equal to 0; if the collision time is less than or equal to the seventh preset time, the deceleration is equal to the first preset value.

[0041] Preferably, different decelerations are determined based on the vehicle slip ratio, current vehicle speed, and collision time. The specific method is as follows:

[0042] When the vehicle speed is less than or equal to the second speed, the slip ratio benchmark value is set to the fifth benchmark value;

[0043] If the vehicle slip ratio is less than the fifth baseline value, then the collision time is compared. If the collision time is greater than the fourth preset time, the deceleration is equal to 0; if the collision time is greater than the first preset time and less than or equal to the fourth preset time, the deceleration is equal to the fourth preset value; if the collision time is less than or equal to the first preset time, the deceleration is equal to the sixth preset value.

[0044] If the vehicle slip ratio is greater than or equal to the fifth baseline value, then the collision time is compared. If the collision time is greater than the sixth preset time, the deceleration is equal to 0. If the collision time is greater than the third preset time and less than or equal to the sixth preset time, the deceleration is equal to the first preset value. If the collision time is less than or equal to the third preset time, the deceleration is equal to the third preset value.

[0045] Preferably, after the AEB system is triggered, the AEB system exits when the following conditions are met;

[0046] When the vehicle speed is greater than the first speed, if the vehicle slip ratio is greater than or equal to the first reference value, the AEB system will disengage when the vehicle speed is 0; if the vehicle slip ratio is less than the first reference value, the AEB system will disengage when the collision time is greater than the tenth preset time.

[0047] When the vehicle speed is less than the first speed but greater than the second speed, if the vehicle slip ratio is greater than or equal to the third reference value, the AEB system will disengage when the vehicle speed is 0; if the vehicle slip ratio is less than the third reference value, the AEB system will disengage when the collision time is greater than the eighth preset time.

[0048] When the vehicle speed is less than or equal to the second speed, if the vehicle slip ratio is greater than or equal to the fifth reference value, the AEB system will disengage when the vehicle speed is 0; if the vehicle slip ratio is less than the fifth reference value, the AEB system will disengage when the collision time is greater than the fifth preset time.

[0049] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0050] The intelligent connected bus AEB control system and method for slippery roads provided by this invention, based on the road conditions during vehicle operation, combines the vehicle's slip ratio, speed, and collision time with obstacles to calculate the emergency braking deceleration of the vehicle under different road conditions. This enables the system to trigger the emergency braking system appropriately on low-traction surfaces, effectively preventing the vehicle from fishtailing due to excessive deceleration on slippery roads. This reduces traffic accidents and improves vehicle safety and operational efficiency.

[0051] This invention can also determine whether a vehicle has entered a low-adhesion road surface by comparing the vehicle slip ratio based on different driving speeds. Then, after the AEB system is triggered, different AEB system exit schemes can be formulated to prevent the rear wheels from locking up easily when the intelligent connected bus brakes suddenly on a wet and slippery road surface, which could cause the vehicle to fishtail and cause a traffic accident. Attached Figure Description

[0052] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0053] Figure 1 The flowchart is shown in Embodiment 1 of the present invention for the AEB control method of intelligent connected buses on slippery road surfaces. Detailed implementation method:

[0054] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0055] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0056] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. Furthermore, it should be understood that the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0057] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0058] Example 1

[0059] like Figure 1 As shown, this embodiment provides an intelligent connected bus AEB control system for slippery road surfaces, including: a vehicle controller and a wheel speed acquisition unit, a motor controller, an image acquisition unit and an AEB system respectively connected to the vehicle controller;

[0060] The wheel speed acquisition unit is mounted on the wheel hub and is used to acquire the wheel speeds of the left and right rear wheels of the vehicle; the motor controller is used to output the motor speed; the image acquisition unit is used to acquire the distance and relative speed to obstacles in front.

[0061] The vehicle controller receives data from the wheel speed acquisition unit, motor controller, and image acquisition unit, and uses the acquired data to calculate the current vehicle speed, vehicle slip ratio, and collision time, and outputs the calculation results to the AEB system.

[0062] The AEB system determines different decelerations based on the current vehicle speed, vehicle slip ratio, and collision time.

[0063] After the vehicle's AEB (Autonomous Emergency Braking) is triggered, the AEB system formulates different AEB exit methods based on the vehicle speed and the vehicle's slip ratio.

[0064] When collecting data, the vehicle controller receives information from the wheel speed acquisition unit, motor controller, and image acquisition unit via CAN messages.

[0065] Example 2

[0066] This embodiment provides an AEB (Automatic Emergency Braking) control method for intelligent connected buses on slippery road surfaces, including:

[0067] S1: Collect vehicle motor speed n, left and right rear wheel speeds, distance to and relative speed Δv from obstacles in front;

[0068] S2: Calculate the current vehicle speed v using the motor speed n, and calculate the overall vehicle slip ratio w based on the wheel speeds of the left and right rear wheels and the current vehicle speed v;

[0069] S3: Calculate the collision time ttc with the obstacle using the acquired distance and relative velocity Δv;

[0070] S4: Determine different decelerations a based on the vehicle slip ratio w, the current vehicle speed v, and the collision time ttc.

[0071] In step S1, when acquiring data, the vehicle controller receives the distance and relative speed Δv information to the obstacle in front from the image acquisition unit, the motor speed n output by the motor controller, and the left rear wheel speed v1 and right rear wheel speed v2 information from the wheel speed acquisition unit via CAN message.

[0072] In step S2, the current vehicle speed v is calculated using the motor speed n, and the overall vehicle slip ratio w is calculated based on the wheel speeds of the left and right rear wheels and the current vehicle speed v. The specific steps are as follows:

[0073] S201: Calculate the current vehicle speed v using the motor speed. The calculation formula is:

[0074]

[0075] Where r is the vehicle tire radius, i1 is the reduction ratio, and i2 is the gear ratio.

[0076] S202: Calculate the left rear wheel slip ratio w1 based on the left rear wheel speed v1 and the current vehicle speed v:

[0077] If the vehicle speed v>0 and v>v1, then the slip ratio of the left rear wheel is... If the vehicle speed v = 0, or v ≤ v1, the slip ratio of the left rear wheel w1 = 0. The specific calculation formula is as follows:

[0078]

[0079] S203: Calculate the right rear wheel slip ratio w2 based on the right rear wheel speed v2 and the current vehicle speed v:

[0080] If the vehicle speed v>0 and v>v2, the slip ratio of the right rear wheel is... If the vehicle speed v = 0, or v ≤ v2, the slip ratio of the right rear wheel w2 = 0. The specific calculation formula is as follows:

[0081]

[0082] S204: The overall vehicle slip ratio w is taken as the maximum of the left rear wheel slip ratio w1 and the right rear wheel slip ratio w2. The formula is:

[0083] w = max(w1, w2) (4)

[0084] In the said step S3, the distance from the front obstacle includes the longitudinal distance and the lateral distance. The time to collision ttc with the obstacle is calculated by using the obtained distance and the relative speed Δv. Specifically:

[0085] If the lateral distance X between the vehicle and the front obstacle > 1 m, there is no collision risk between the whole vehicle and the obstacle, and the time to collision ttc is equal to infinity. Generally, when the time to collision ttc exceeds 10 s, AEB will not be triggered. Here, a value larger than 10 is set, and ttc = 100 is set.

[0086] If the lateral distance X between the vehicle and the front obstacle ≤ 1 m, and at the same time the relative speed Δv ≥ 0, that is, the speed of the obstacle is greater than the speed of the vehicle, the time to collision ttc is equal to infinity. Generally, when the time to collision ttc exceeds 10 s, AEB will not be triggered. Here, a value larger than 10 is set, and ttc = 100 is set.

[0087] If the lateral distance X between the vehicle and the front obstacle ≤ 1 m, and at the same time the relative speed Δv < 0, that is, the speed of the obstacle is less than the speed of the vehicle, the time to collision is set as The calculation formula is as follows:

[0088] [[ID=?]]

[0089] In the said step S4, different decelerations a are determined according to the slip ratio w of the whole vehicle, the current vehicle speed v and the time to collision ttc. Specifically:

[0090] When the vehicle speed v > 50 km / h, the reference values of the slip ratio are set to 3% and 5% respectively.

[0091] If the slip ratio w of the whole vehicle < 3%, compare the time to collision. If ttc > 6 s, the vehicle does not need to brake and the deceleration a = 0; if 2.7 < ttc ≤ 6, the vehicle performs a slow braking and the deceleration a = -2.5 m / s

[0089] ; if ttc ≤ 2.7, the vehicle performs an emergency braking and the deceleration a = -3.5 m / s 2 ;

[0092] If the slip ratio of the whole vehicle 3% ≤ w < 5%, compare the time to collision. If ttc > 8 s, the vehicle does not need to brake and the deceleration a = 0; if 5 < ttc ≤ 8, the vehicle performs a slow braking and the deceleration a = -2 m / s 2 ; if ttc ≤ 3.2, the vehicle performs an emergency braking and the deceleration a = -3 m / s 2 ;

[0093] If the slip ratio w of the whole vehicle ≥ 5%, compare the time to collision. If ttc > 9.5 s, the vehicle does not need to brake and the deceleration a = 0; if ttc ≤ 9.5, the vehicle performs a uniform braking and the deceleration a = -2 m / s 2 It should be noted that there seems to be an incomplete formula in ID 10 - 12 in the original text. I have translated it as accurately as possible based on the available content.。

[0094] The specific calculation formula is as follows:

[0095]

[0096] When 30 < v ≤ 50 km / h, the reference values of the slip ratio are set to 6% and 7% respectively;

[0097] If the overall vehicle slip ratio w < 6%, compare the collision time. If ttc > 5 s, the vehicle does not need to brake and the deceleration a = 0; if 2.7 < ttc ≤ 5, the vehicle performs a slow braking and the deceleration a = -2 m / s 2 ; if ttc ≤ 2.7, the vehicle performs an emergency braking and the deceleration a = -3 m / s 2 ;

[0098] If the overall vehicle slip ratio 6% ≤ w < 7%, compare the collision time. If ttc > 6 s, the vehicle does not need to brake and the deceleration a = 0; if 4 < ttc ≤ 6, the vehicle performs a slow braking and the deceleration a = -1.4 m / s 2 ; if ttc ≤ 4, the vehicle performs an emergency braking and the deceleration a = -2 m / s 2 ;

[0099] If the overall vehicle slip ratio w ≥ 7%, compare the collision time. If ttc > 7 s, the vehicle does not need to brake and the deceleration a = 0; if ttc ≤ 7, the vehicle performs a uniform braking and the deceleration a = -1 m / s 2 ;

[0100] The specific calculation formula is as follows:

[0101]

[0102] When v ≤ 30 km / h, the reference value of the slip ratio is set to 7.5%;

[0103] If the overall vehicle slip ratio w < 7.5%, compare the collision time. If ttc > 4.5 s, the vehicle does not need to brake and the deceleration a = 0; if 2.7 < ttc ≤ 4.5, the vehicle performs a slow braking and the deceleration a = -1.8 m / s 2 ; if ttc ≤ 2.7, the vehicle performs an emergency braking and the deceleration a = -2.2 m / s 2 ;

[0104] If the overall vehicle slip ratio w ≥ 7.5%, compare the collision time. If ttc > 6 s, the vehicle does not need to brake and the deceleration a = 0; if 4 < ttc ≤ 6, the vehicle performs a slow braking and the deceleration a = -1 m / s 2 ; if ttc ≤ 4, the vehicle performs an emergency braking and the deceleration a = -1.5 m / s 2 。

[0105] The specific calculation formula is as follows:

[0106]

[0107] The AEB control method for intelligent connected buses on wet and slippery roads also includes that after the AEB system is triggered, different AEB exit methods are formulated according to the vehicle speed v and the vehicle slip ratio w, specifically as follows:<0000​​​​​​​​​​​​​​​​The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0114] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. An intelligent connected bus AEB control system for slippery road surfaces, characterized in that, include: The vehicle controller, and the wheel speed acquisition unit, motor controller, image acquisition unit and AEB system connected to the vehicle controller respectively; The wheel speed acquisition unit is mounted on the wheel hub and is used to acquire the wheel speeds of the left and right rear wheels of the vehicle; the motor controller is used to output the motor speed; the image acquisition unit is used to acquire the distance and relative speed to obstacles in front. The vehicle controller receives data from the wheel speed acquisition unit, the motor controller, and the image acquisition unit, and uses the acquired data to calculate the current vehicle speed, the vehicle slip ratio, and the collision time, respectively, and outputs the calculation results to the AEB system; the vehicle slip ratio is the maximum value of the left rear wheel slip ratio and the right rear wheel slip ratio; The AEB system determines different decelerations based on the current vehicle speed, vehicle slip ratio, and collision time, using the following method: When the vehicle speed is greater than the first speed, the slip ratio reference values ​​are set as the first reference value and the second reference value, respectively. If the vehicle slip ratio is less than the first benchmark value, then the collision time is compared. If the collision time is greater than the sixth preset time, the deceleration is equal to 0; if the collision time is greater than the first preset time and less than or equal to the sixth preset time, the deceleration is equal to the seventh preset value. If the collision time is less than or equal to the first preset time, the deceleration is equal to the ninth preset value; If the vehicle slip ratio is greater than or equal to the first reference value and less than the second reference value, then the collision time is compared. If the collision time is greater than the eighth preset time, the deceleration is equal to 0; if the collision time is greater than the fifth preset time and less than or equal to the eighth preset time, the deceleration is equal to the fifth preset value. If the collision time is less than or equal to the second preset time, the deceleration is equal to the eighth preset value; If the vehicle slip ratio is greater than or equal to the second benchmark value, then the collision time is compared. If the collision time is greater than the ninth preset time, the deceleration is equal to 0; if the collision time is less than or equal to the ninth preset time, the deceleration is equal to the fifth preset value. After the AEB system is triggered, it will exit when the following conditions are met; When the vehicle speed is greater than the first speed, if the vehicle slip ratio is greater than or equal to the first reference value, the AEB system will disengage when the vehicle speed is 0; if the vehicle slip ratio is less than the first reference value, the AEB system will disengage when the collision time is greater than the tenth preset time. When the vehicle speed is less than the first speed but greater than the second speed, if the vehicle slip ratio is greater than or equal to the third reference value, the AEB system will disengage when the vehicle speed is 0; if the vehicle slip ratio is less than the third reference value, the AEB system will disengage when the collision time is greater than the eighth preset time. When the vehicle speed is less than or equal to the second speed, if the vehicle slip ratio is greater than or equal to the fifth reference value, the AEB system will disengage when the vehicle speed is 0; if the vehicle slip ratio is less than the fifth reference value, the AEB system will disengage when the collision time is greater than the fifth preset time. Based on consideration of road conditions, combined with vehicle slip ratio, vehicle speed and collision time with obstacles, the emergency braking deceleration of the vehicle under different road conditions is calculated to achieve reasonable triggering of the emergency braking system on low-adhesion roads.

2. The intelligent connected bus AEB control system for slippery road surfaces as described in claim 1, characterized in that, After the vehicle's AEB is triggered, the AEB system formulates different AEB exit methods based on the vehicle speed and the overall vehicle slip ratio.

3. The intelligent connected bus AEB control system for slippery road surfaces as described in claim 2, characterized in that, When collecting data, the vehicle controller receives information from the wheel speed acquisition unit, motor controller, and image acquisition unit via CAN messages.

4. A method for AEB control of intelligent connected buses on slippery roads, characterized in that, include: Collect data on vehicle motor speed, left and right rear wheel speeds, as well as distance and relative speed to obstacles in front; The current vehicle speed is calculated using the motor speed, and the overall vehicle slip ratio is calculated based on the left and right rear wheel speeds and the current vehicle speed; the overall vehicle slip ratio is the maximum value of the left rear wheel slip ratio and the right rear wheel slip ratio. Calculate the collision time with the obstacle using the obtained distance and relative velocity; Different deceleration rates are determined based on the vehicle's slip ratio, current speed, and collision time. The specific method is as follows: When the vehicle speed is greater than the first speed, the slip ratio reference values ​​are set as the first reference value and the second reference value, respectively. If the vehicle slip ratio is less than the first benchmark value, then the collision time is compared. If the collision time is greater than the sixth preset time, the deceleration is equal to 0; if the collision time is greater than the first preset time and less than or equal to the sixth preset time, the deceleration is equal to the seventh preset value. If the collision time is less than or equal to the first preset time, the deceleration is equal to the ninth preset value; If the vehicle slip ratio is greater than or equal to the first reference value and less than the second reference value, then the collision time is compared. If the collision time is greater than the eighth preset time, the deceleration is equal to 0; if the collision time is greater than the fifth preset time and less than or equal to the eighth preset time, the deceleration is equal to the fifth preset value. If the collision time is less than or equal to the second preset time, the deceleration is equal to the eighth preset value; If the vehicle slip ratio is greater than or equal to the second benchmark value, then the collision time is compared. If the collision time is greater than the ninth preset time, the deceleration is equal to 0; if the collision time is less than or equal to the ninth preset time, the deceleration is equal to the fifth preset value. After the AEB system is triggered, it will exit when the following conditions are met; When the vehicle speed is greater than the first speed, if the vehicle slip ratio is greater than or equal to the first reference value, the AEB system will disengage when the vehicle speed is 0; if the vehicle slip ratio is less than the first reference value, the AEB system will disengage when the collision time is greater than the tenth preset time. When the vehicle speed is less than the first speed but greater than the second speed, if the vehicle slip ratio is greater than or equal to the third reference value, the AEB system will disengage when the vehicle speed is 0; if the vehicle slip ratio is less than the third reference value, the AEB system will disengage when the collision time is greater than the eighth preset time. When the vehicle speed is less than or equal to the second speed, if the vehicle slip ratio is greater than or equal to the fifth reference value, the AEB system will disengage when the vehicle speed is 0; if the vehicle slip ratio is less than the fifth reference value, the AEB system will disengage when the collision time is greater than the fifth preset time. Based on consideration of road conditions, combined with vehicle slip ratio, vehicle speed and collision time with obstacles, the emergency braking deceleration of the vehicle under different road conditions is calculated to achieve reasonable triggering of the emergency braking system on low-adhesion roads.

5. The intelligent connected bus AEB control method for slippery road surfaces as described in claim 4, characterized in that, Calculate the left rear wheel slip ratio based on the left rear wheel speed and the current vehicle speed: If the vehicle speed is equal to 0, or less than or equal to the speed of the left rear wheel, then the slip ratio of the left rear wheel is 0. If the vehicle speed is greater than 0 and greater than the speed of the left rear wheel, the formula for calculating the slip ratio of the left rear wheel is as follows: in, The speed of the left rear wheel. Current vehicle speed The slip ratio of the left rear wheel; Calculate the right rear wheel slip ratio based on the right rear wheel speed and the current vehicle speed: If the vehicle speed is equal to 0, or less than or equal to the right rear wheel speed, then the right rear wheel slip ratio is 0. If the vehicle speed is greater than 0 and greater than the speed of the right rear wheel, the formula for calculating the slip ratio of the right rear wheel is as follows: in, The speed of the left rear wheel. Current vehicle speed The slip ratio of the left rear wheel.

6. The intelligent connected bus AEB control method for slippery road surfaces as described in claim 4, characterized in that, The distance to the obstacle ahead includes longitudinal and lateral distances. The collision time with the obstacle is calculated using the longitudinal and lateral distances and the relative speed, as follows: If the lateral distance X is greater than the preset distance, there is no risk of collision between the vehicle and the obstacle, and the collision time is infinite. If the lateral distance X is less than or equal to the preset distance and the relative velocity is greater than or equal to 0, the collision time is infinite. If the lateral distance X is less than or equal to the preset distance and the relative velocity is less than 0, the collision time is determined according to the following formula: in, For the collision time, The vertical distance is... This refers to relative velocity.

7. The intelligent connected bus AEB control method for slippery road surfaces as described in claim 4, characterized in that, The method for determining different decelerations based on the vehicle slip ratio, current vehicle speed, and collision time is as follows: When the vehicle speed is less than or equal to the first speed and greater than the second speed, the slip ratio reference values ​​are set as the third and fourth reference values, respectively. If the vehicle slip ratio is less than the third benchmark value, then the collision time is compared. If the collision time is greater than the fifth preset time, the deceleration is equal to 0; if the collision time is greater than the first preset time and less than or equal to the fifth preset time, the deceleration is equal to the fifth preset value. If the collision time is less than or equal to the first preset time, the deceleration is equal to the eighth preset value; If the vehicle slip ratio is greater than or equal to the third benchmark value and less than the fourth benchmark value, then the collision time is compared. If the collision time is greater than the sixth preset time, the deceleration is equal to 0; if the collision time is greater than the third preset time and less than or equal to the sixth preset time, the deceleration is equal to the second preset value. If the collision time is less than or equal to the third preset time, the deceleration is equal to the fifth preset value; If the vehicle slip ratio is greater than or equal to the fourth baseline value, then the collision time is compared. If the collision time is greater than the seventh preset time, the deceleration is equal to 0; if the collision time is less than or equal to the seventh preset time, the deceleration is equal to the first preset value.

8. The intelligent connected bus AEB control method for slippery road surfaces as described in claim 4, characterized in that, The method for determining different decelerations based on the vehicle slip ratio, current vehicle speed, and collision time is as follows: When the vehicle speed is less than or equal to the second speed, the slip ratio benchmark value is set to the fifth benchmark value; If the vehicle slip ratio is less than the fifth baseline value, then the collision time is compared. If the collision time is greater than the fourth preset time, the deceleration is equal to 0; if the collision time is greater than the first preset time and less than or equal to the fourth preset time, the deceleration is equal to the fourth preset value. If the collision time is less than or equal to the first preset time, the deceleration is equal to the sixth preset value; If the vehicle slip ratio is greater than or equal to the fifth baseline value, then the collision time is compared. If the collision time is greater than the sixth preset time, the deceleration is equal to 0; if the collision time is greater than the third preset time and less than or equal to the sixth preset time, the deceleration is equal to the first preset value. If the collision time is less than or equal to the third preset time, the deceleration is equal to the third preset value.

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