Brake control method, system and equipment and computer readable storage medium

Abstract

A brake control method, system and device and a computer readable storage medium relate to the technical field of electromechanical brake-by-wire, and specifically comprise: acquiring a road surface type corresponding to a road surface where a target vehicle is currently located, and a first optimal slip rate and a second optimal slip rate corresponding to different moments of the target vehicle, the first optimal slip rate is obtained based on an electronic mechanical brake-by-wire system, and the second optimal slip rate is obtained based on an intelligent driving assistance system; when it is determined that the road surface type is credible according to the first optimal slip rate and the second optimal slip rate, target braking force is determined based on the first optimal slip rate; and brake control is conducted based on the target brake force. The problems that in the first cycle of the function of the anti-lock braking system, braking is conducted only by stepping on the pedal, so that braking force is too large, and the wheel speed is reduced or increased greatly are solved.

Description

Technical Field

[0001] The present application relates to the technical field of electronic mechanical wire-controlled braking, and in particular to a braking control method, system, device and computer-readable storage medium. Background Art

[0002] With the development of intelligent driving technology, especially in the application of ADAS (Advanced Driver Assistance System), the performance requirements of automobile braking systems are increasing. Traditional hydraulic braking systems can no longer meet the increasingly stringent requirements of intelligent driving due to their long response time, while EMB (Electric Mechanical Braking) has gradually become an ideal choice for intelligent braking systems due to its fast response speed and high control accuracy.

[0003] At present, EMB has excellent performance in braking response, and can reach the locking clamping force in less than 100 milliseconds, thus meeting the high requirements of ADAS functions for braking performance and promoting the intelligentization of the whole vehicle. However, despite the fast response speed of EBM, there are still certain technical problems, especially the excessive braking force and large wheel speed reduction or increase caused by braking only by pedaling in the first cycle of ABS (Anti-lock Braking System) function.

[0004] In summary, excessive braking force and large wheel speed reduction or increase caused by braking only by pedaling in the first cycle of the ABS function are problems that need to be solved urgently. Summary of the invention

[0005] The present application provides a braking control method, system, device and computer-readable storage medium, which can solve the technical problems existing in the prior art of excessive braking force and large wheel speed reduction or increase caused by braking only by pedaling in the first cycle of the ABS function.

[0006] In a first aspect, an embodiment of the present application provides a braking control method, the braking control method comprising:

[0007] Acquire a road type corresponding to a road surface currently located by the target vehicle, and a first optimal slip ratio and a second optimal slip ratio corresponding to the target vehicle at different times, wherein the first optimal slip ratio is acquired based on an electronic mechanical brake-by-wire system, and the second optimal slip ratio is acquired based on an intelligent driving assistance system;

[0008] When it is determined that the road type is credible according to the first optimal slip ratio and the second optimal slip ratio, determining a target braking force based on the first optimal slip ratio;

[0009] Braking control is performed based on the target braking force.

[0010] In combination with the first aspect, in one implementation, obtaining the road surface type corresponding to the road surface on which the target vehicle is currently located includes:

[0011] Obtaining target parameters corresponding to the road surface on which the target vehicle is currently located, wherein the target parameters include front and rear suspension loads on the road surface, road braking force, and road slip rate;

[0012] The road surface type corresponding to the current road surface is determined based on the target parameters.

[0013] In combination with the first aspect, in one implementation manner, the first optimal slip ratio includes a first optimal slip ratio at a first moment corresponding to a first moment and a first optimal slip ratio at a second moment corresponding to a second moment, the second optimal slip ratio includes a first optimal slip ratio at a first moment corresponding to the first moment and a second optimal slip ratio at a second moment corresponding to the second moment, the first moment is earlier than the second moment, and before the step of determining that the road surface type is credible according to the first optimal slip ratio and the second optimal slip ratio, the method further includes:

[0014] Determining whether a difference between a first optimal slip ratio at the first moment and a second optimal slip ratio at the first moment is less than a preset first difference threshold;

[0015] If so, it is determined that the road surface type is credible;

[0016] If not, the credibility of the road surface type is determined based on the difference between the first optimal slip ratio at the second moment and the second optimal slip ratio at the second moment.

[0017] In combination with the first aspect, in one implementation, determining the credibility of the road surface type based on the difference between the first optimal slip rate at the second moment and the second optimal slip rate at the second moment includes:

[0018] determining whether a difference between the first optimal slip ratio at the second moment and the second optimal slip ratio at the second moment is less than a preset second difference threshold;

[0019] If so, it is determined that the road surface type is credible;

[0020] If not, the credibility of the road surface type is determined based on the difference between the first optimal slip ratio at the first moment and the first optimal slip ratio at the second moment.

[0021] In combination with the first aspect, in one implementation, determining the credibility of the road type based on the difference between the first optimal slip ratio at the first moment and the first optimal slip ratio at the second moment includes:

[0022] determining whether a difference between the first optimal slip ratio at the second moment and the first optimal slip ratio at the first moment is less than a preset third difference threshold;

[0023] If so, it is determined that the road surface type is credible;

[0024] If not, it is determined that the road surface type is unreliable and a wheel identification failure is reported.

[0025] In combination with the first aspect, in one implementation manner, determining the target braking force based on the first optimal slip ratio includes:

[0026] Determining a maximum braking force corresponding to a first optimal slip ratio based on a preset mapping relationship between the slip ratio and the braking force;

[0027] The maximum braking force is used as the target braking force.

[0028] In a second aspect, an embodiment of the present application provides a braking control system, the braking control system comprising:

[0029] A first processing module, which is used to obtain a road type corresponding to a road surface currently located by the target vehicle, a first optimal slip ratio and a second optimal slip ratio corresponding to the target vehicle at different times, wherein the first optimal slip ratio is obtained based on an electronic mechanical wire control brake system, and the second optimal slip ratio is obtained based on an intelligent driving assistance system;

[0030] a second processing module, configured to determine a target braking force based on the first optimal slip ratio when it is determined that the road type is credible according to the first optimal slip ratio and the second optimal slip ratio;

[0031] A third processing module is configured to perform braking control based on the target braking force.

[0032] In conjunction with the second aspect, in one implementation, the first processing module is specifically configured to:

[0033] Obtaining target parameters corresponding to the road surface on which the target vehicle is currently located, wherein the target parameters include front and rear suspension loads on the road surface, road braking force, and road slip rate;

[0034] The road surface type corresponding to the current road surface is determined based on the target parameters.

[0035] In a third aspect, an embodiment of the present application provides a braking control device, which includes a processor, a memory, and a braking control program stored in the memory and executable by the processor, wherein when the braking control program is executed by the processor, the steps of the braking control method as described in any one of the above items are implemented.

[0036] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, on which a braking control program is stored, wherein when the braking control program is executed by a processor, the steps of the braking control method as described in any one of the above items are implemented.

[0037] The beneficial effects brought by the technical solution provided in the embodiments of the present application include:

[0038] By obtaining the road surface type corresponding to the current road surface on which the target vehicle is located, the first optimal slip ratio and the second optimal slip ratio corresponding to the target vehicle at different times, the first optimal slip ratio is obtained based on the electronic mechanical wire control brake system, and the second optimal slip ratio is obtained based on the intelligent driving assistance system; when the road surface type is determined to be credible based on the first optimal slip ratio and the second optimal slip ratio, the target braking force is determined based on the first optimal slip ratio; braking control is performed based on the target braking force, that is, the present application determines the accurate road surface type corresponding to the current road surface, and then obtains the target braking force based on the first optimal slip ratio, and finally controls braking based on the target braking force, thereby avoiding the problem of wheel locking or excessive wheel speed reduction or increase caused by excessive braking caused by braking by pedaling. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a flow chart of an embodiment of a braking control method of the present application;

[0040] Figure 2 For this application Figure 1 A detailed flow chart of step S10;

[0041] Figure 3 This is a schematic diagram of wheel speed changes on different road surfaces in an embodiment of the braking control method of this application;

[0042] Figure 4 This is a schematic diagram of the functional modules of an embodiment of a brake control system of the present application;

[0043] Figure 5 This is a schematic diagram of the hardware structure of the brake control device involved in the embodiment of the present application. DETAILED DESCRIPTION

[0044] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0045] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0046] In a first aspect, an embodiment of the present application provides a braking control method.

[0047] In one embodiment, referring to Figure 1 , Figure 1 This is a flow chart of an embodiment of the braking control method of the present application.

[0048] like Figure 1 As shown, the braking control method includes:

[0049] Step S10: Obtain the road type corresponding to the road surface on which the target vehicle is currently located, and the first optimal slip rate and the second optimal slip rate corresponding to the target vehicle at different times, wherein the first optimal slip rate is obtained based on the electronic mechanical wire control brake system, and the second optimal slip rate is obtained based on the intelligent driving assistance system.

[0050] Exemplarily, in the embodiment of the present application, the road surface type refers to the ground condition on which the target vehicle is traveling, which describes the friction characteristics of different types of roads. Common road surface types include ice roads, snow (compacted) roads, cement (wet) roads, asphalt (wet), concrete (wet), asphalt or concrete (dry), etc.; the first optimal slip rate refers to the optimal slip rate of the corresponding road surface at different times obtained by the EMB system itself through road surface recognition, which includes the first optimal slip rate at the first moment and the first optimal slip rate at the second moment. The first optimal slip rate is an important input to the vehicle control system, which reflects the sliding condition between the tires of the current vehicle and the road surface, and determines how the system adjusts the braking force, traction and stability of the vehicle; the second optimal slip rate refers to the optimal slip rate of the corresponding road surface at different times obtained by the ADAS system itself through road surface image recognition processing, which is a key parameter in vehicle dynamics to measure the sliding state between the vehicle tires and the road surface, and the second optimal slip rate includes the second optimal slip rate at the first moment and the second optimal slip rate at the second moment.

[0051] The first optimal slip rate and the second optimal slip rate are merely the optimal slip rates corresponding to the road surfaces identified by the vehicle's two independent EMB electronic mechanical brake-by-wire systems and ADAS intelligent driving system at different times in real time. If the road surfaces identified by the two independent systems at the same time are both icy, the first optimal slip rate, the second optimal slip rate and the optimal slip rate corresponding to the current icy road surface are exactly the same.

[0052] The optimal slip ratio is usually expressed as a percentage, which represents the ratio of the difference between the vehicle body speed and the wheel speed to the vehicle body speed.

[0053] Table 1 Mapping relationship between road surface type and optimal slip rate

[0054]

[0055]

[0056] It can be understood that, as shown in Table 1, different road types have unique corresponding optimal slip rates. For example, when the target wheel road type is an icy road, the corresponding optimal slip rate is 6%. The optimal slip rate corresponding to each road type has a corresponding adhesion coefficient. The optimal slip rate can be controlled to achieve maximum braking efficiency of the vehicle and ensure driving safety.

[0057] Specifically, when the user is driving the vehicle normally, the EMB system can be used to identify the first optimal slip rate corresponding to the road surface of the target vehicle to determine the slip condition of the target vehicle; the road surface image can be filtered in real time by the vehicle's ADAS front and rear cameras to extract road surface morphology feature parameters, and then the extracted feature parameters are brought into the constructed road surface feature model to calculate the road surface type on which the target vehicle is located at this time according to the road surface feature model, wherein the road surface feature model is common knowledge in the field and will not be elaborated here for the sake of brevity of description; the second optimal slip rate of the road surface type at this time is obtained from the optimal slip rate information corresponding to the road surface type pre-stored in the ADAS system according to the calculated road surface type.

[0058] Step S20: When it is determined that the road type is credible according to the first optimal slip ratio and the second optimal slip ratio, a target braking force is determined based on the first optimal slip ratio.

[0059] Exemplarily, in the embodiment of the present application, the target braking force refers to the braking force that should be applied by the target vehicle during the braking process to achieve the best braking effect, so as to ensure the optimization of the vehicle braking process, so that the vehicle braking process can not only ensure the maximum braking efficiency, but also avoid instability or inefficiency caused by excessively high or low slip rates.

[0060] Specifically, by comparing the first optimal slip ratio with the second optimal slip ratio, it is possible to evaluate whether the current road type of the target vehicle is accurate (i.e., credible); if the first optimal slip ratio and the second optimal slip ratio match well and have no obvious deviation, it means that the road type is credible; once it is determined that the road type is credible, then the optimal slip ratio corresponding to the road type (i.e., the first optimal slip ratio or the second optimal slip ratio) is also credible, and the braking force (i.e., the target braking force) required to achieve the optimal slip ratio corresponding to the road type can be determined based on the mapping relationship between the slip ratio and the braking force, wherein on a wet road surface (with a larger slip ratio), the braking effect can be improved by reducing the braking force; and on a dry road surface (with a smaller slip ratio), the braking effect can be improved by increasing the braking force.

[0061] Step S30: Perform braking control based on the target braking force.

[0062] Exemplarily, in an embodiment of the present application, after calculating the target braking force required for braking the target vehicle, the braking pressure or braking force distribution of each wheel can be accurately adjusted through the EMB system to ensure that the target vehicle obtains the best deceleration effect under different driving conditions. At the same time, the precise target braking force can avoid excessive braking (causing wheel slip or excessive friction) or insufficient braking (causing insufficient deceleration), ensuring that the vehicle is always in the best braking state and avoiding the danger caused by excessive or slow deceleration.

[0063] The present application obtains the road surface type corresponding to the road surface currently located by the target vehicle, the first optimal slip rate and the second optimal slip rate corresponding to the target vehicle at different times, the first optimal slip rate is obtained based on the electronic mechanical wire control brake system, and the second optimal slip rate is obtained based on the intelligent driving assistance system; when the road surface type is determined to be credible based on the first optimal slip rate and the second optimal slip rate, the target braking force is determined based on the first optimal slip rate; braking control is performed based on the target braking force, that is, the present application determines the accurate road surface type corresponding to the current road surface, so the first optimal slip rate corresponding to the road surface type is also accurate, and then the target braking force is obtained based on the first optimal slip rate, and finally the braking is controlled according to the target braking force, thereby avoiding the problem of wheel locking or excessive wheel speed reduction or increase caused by excessive braking caused by braking by pedaling.

[0064] Further, in one embodiment, referring to Figure 2 As shown, the step of obtaining the road type corresponding to the road surface on which the target vehicle is currently located includes:

[0065] Step S101: obtaining target parameters corresponding to the road surface on which the target vehicle is currently located, wherein the target parameters include front and rear suspension loads, road braking force, and road slip rate;

[0066] Step S102: Determine the road surface type corresponding to the current road surface based on the target parameters.

[0067] Exemplarily, in the embodiment of the present application, the mapping relationship between the preset road surface type and the slip rate can be obtained through test calibration, which is not limited here; the front and rear suspension loads on the road surface refer to the loads acting on the front and rear suspension systems caused by uneven road surface, driving state or changes in road conditions during the driving process of the target vehicle, which directly affects the vehicle's handling, comfort and driving stability.

[0068] Specifically, the front and rear suspension loads of the target vehicle can be obtained through the vehicle suspension system and transmitted to the vehicle EMB system in real time through the vehicle CAN network; when the user steps on the brake pedal, the EMB system sends a corresponding braking force request to the wheel-end EMB actuator according to the driver's brake pedal request, and the EMB wheel-end actuator clamps the wheel and feeds back the actual wheel-end clamping force in real time; when the user brakes each time, the wheel speed information and vehicle speed information can be read in real time, so as to obtain the road slip rate of each wheel according to the vehicle speed information and wheel speed information, where the calculation formula of the road slip rate λ is as follows:

[0069]

[0070] Where V is the vehicle speed, rω is the wheel speed, and λ is the road slip rate; when the wheel is purely rolling, rω=V, λ=0; when the wheel is locked and purely sliding, rω=0, λ=100%; when the wheel rolls and slides at the same time, V>rω, 0<λ<100%; among them, the greater the road slip rate of the wheel, the greater the proportion of the sliding component in the wheel's movement.

[0071] It can be understood that after obtaining the three target parameters of the front and rear suspension load, road braking force, and road slip rate corresponding to the current road surface of the target vehicle through the EMB system, the target parameters are compared with the preset road front and rear suspension load, preset road braking force, and preset road slip rate pre-stored in the system to obtain a road surface type that matches the target parameters. This road surface type is the road surface type, that is, the road surface on which the target vehicle is currently traveling; among them, the specific values ​​of the preset road front and rear suspension load, preset road braking force, and preset road slip rate can be obtained through test calibration and are not limited here.

[0072] It should be noted that according to the established vehicle braking model, when the front and rear suspension loads are the same and the same ground braking force F is applied to the vehicle, the wheel speed reduction ranges of the vehicle wheels on different road surfaces vary greatly. Figure 3 As shown in the figure, under the same vehicle front and rear suspension loads, when the ground braking force increases from 0 to F, the wheel speed of the high adhesion road surface decreases less, and the corresponding wheel speed is ω c; On low-adhesion roads, the wheel speed decreases significantly, and the corresponding wheel speed is ω d . From the calculation formula of the road slip rate, it can be seen that the speed V of the target vehicle is constant, and the corresponding slip rate can be calculated according to the vehicle wheel speed. It should be understood that under different road types, even if the front and rear suspension loads of the vehicle are the same and the applied ground braking force is the same, different slip rates will correspond.

[0073] Further, in one embodiment, the first optimal slip ratio includes a first optimal slip ratio at a first moment corresponding to a first moment and a first optimal slip ratio at a second moment corresponding to a second moment, the second optimal slip ratio includes a first optimal slip ratio at a first moment corresponding to the first moment and a second optimal slip ratio at a second moment corresponding to the second moment, the first moment is earlier than the second moment, and before the step of determining that the road surface type is credible according to the first optimal slip ratio and the second optimal slip ratio, the method further includes:

[0074] Determining whether a difference between a first optimal slip ratio at the first moment and a second optimal slip ratio at the first moment is less than a preset first difference threshold;

[0075] If so, it is determined that the road surface type is credible;

[0076] If not, the credibility of the road surface type is determined based on the difference between the first optimal slip ratio at the second moment and the second optimal slip ratio at the second moment.

[0077] Exemplarily, in the embodiment of the present application, the first optimal slip rate at the first moment refers to the slip rate data between the vehicle tire and the ground by the EMB system at the first moment, reflecting the relative slip degree between the wheel and the road surface; the first optimal slip rate at the second moment refers to the slip rate data recorded by the EMB system at the second moment, reflecting the slip rate of the vehicle at a later point in time, and the data at the first moment occurs before the second moment; the second optimal slip rate at the first moment and the second optimal slip rate at the second moment refer to the optimal slip rate data obtained by the ADAS system at different moments, and the preset first difference threshold is used to determine whether the first optimal slip rate and the second optimal slip rate are close enough, and the specific value can be determined according to actual needs and is not limited here.

[0078] It should be noted that the first optimal slip rates corresponding to the four wheels of the target vehicle can be obtained in real time through the EMB system. When the difference between the first optimal slip rate at the first moment and the second optimal slip rate at the first moment of one of the wheels is less than the preset first difference threshold, it means that the road surface type corresponding to the wheel is credible. At the same time, it is necessary to judge whether the road surface types corresponding to the remaining three wheels are credible. The judgment process is consistent with the method for one wheel mentioned above. For the sake of simplicity of description, it is not limited here. When the road surface types corresponding to the four wheels are all credible, the road surface type corresponding to the target vehicle is credible.

[0079] Specifically, firstly, whether the road surface type is credible is preliminarily determined by judging whether the difference between the first best slip rate at the first moment and the second best slip rate at the first moment of the target vehicle is less than the preset first difference threshold. If the difference between the first best slip rate at the first moment and the second best slip rate at the first moment is less than the preset first difference threshold, it means that the first best slip rate is close to the second best slip rate at the first moment, that is, it indicates that the dynamic characteristics of the vehicle at the first moment match the road surface type. Therefore, it can be considered that the road surface type at the first moment is credible, and then no other judgment is made, and subsequent analysis and control can be directly performed based on the road surface type. If the difference between the first best slip rate at the first moment and the second best slip rate at the first moment is ≥ the preset first difference threshold, it means that there is a large deviation between the first best slip rate at the first moment and the second best slip rate at the first moment, that is, the road surface information obtained at this time is not accurate enough, and therefore it is necessary to observe whether the first best slip rate at the second moment corresponding to the vehicle at a later moment (i.e., the second moment) still deviates from the second best slip rate at the second moment, that is, the credibility of the road surface type is determined based on the difference between the first best slip rate at the second moment and the second best slip rate at the second moment.

[0080] It can be understood that the embodiment of the present application evaluates whether the current road type meets expectations by comparing the first optimal slip rate (from the first moment to the second moment) with the second optimal slip rate, that is, by comparing time data to reduce the impact of fluctuations at a single moment and improve the accuracy of judgment.

[0081] Further, in one embodiment, the determining the credibility of the road type based on the difference between the first optimal slip ratio at the second moment and the second optimal slip ratio at the second moment includes:

[0082] determining whether a difference between the first optimal slip ratio at the second moment and the second optimal slip ratio at the second moment is less than a preset second difference threshold;

[0083] If so, it is determined that the road surface type is credible;

[0084] If not, the credibility of the road surface type is determined based on the difference between the first optimal slip ratio at the first moment and the first optimal slip ratio at the second moment.

[0085] Exemplarily, in the embodiment of the present application, the preset second difference threshold is used to determine whether the difference between the two slip rates is acceptable, and its specific value can be determined according to actual needs and is not limited here; specifically, when the road surface type obtained by the target vehicle at the first moment is unreliable, continue to determine whether the road surface type obtained at the second moment is credible, that is, by determining whether the difference between the first best slip rate at the second moment and the second best slip rate at the second moment is less than the preset second difference threshold; if the difference between the first best slip rate at the second moment and the second best slip rate at the second moment is less than the preset second difference threshold, it means that the first best slip rate at the second moment is close to the second best slip rate at the second moment, indicating that the vehicle is at the The dynamic characteristics at the two moments match the road surface type, so it can be considered that the road surface type at the second moment is credible; if the difference between the first best slip rate at the second moment and the second best slip rate at the second moment is ≥ the preset second difference threshold, it means that there is a large deviation between the first best slip rate at the second moment and the second best slip rate at the second moment, that is, the road surface information obtained at this time is not accurate enough, so it is necessary to judge whether the deviation between the first best slip rate at the first moment collected at the first moment and the first best slip rate at the second moment collected at the second moment is within an acceptable range, that is, to determine the credibility of the road surface type based on the difference between the first best slip rate at the first moment and the first best slip rate at the second moment.

[0086] Further, in one embodiment, the determining the credibility of the road type based on the difference between the first optimal slip ratio at the first moment and the first optimal slip ratio at the second moment includes:

[0087] determining whether a difference between the first optimal slip ratio at the second moment and the first optimal slip ratio at the first moment is less than a preset third difference threshold;

[0088] If so, it is determined that the road surface type is credible;

[0089] If not, it is determined that the road surface type is unreliable and a wheel identification failure is reported.

[0090] Exemplarily, in the embodiment of the present application, the specific value of the preset third difference threshold can be determined according to actual needs and is not limited here; specifically, if the difference between the first best slip rate at the second moment and the first best slip rate at the first moment is less than the preset third difference threshold, it means that the deviation between the first best slip rate at the second moment and the first best slip rate at the first moment is very small, then it can be considered that the road surface type obtained at the second moment is credible; if the difference between the first best slip rate at the second moment and the first best slip rate at the first moment is ≥ the preset third difference threshold, it means that the first best slip rate at the second moment not only has a large deviation from the second best slip rate at the second moment, but also has a large deviation from the first best slip rate at the second moment, that is, it indicates that the road surface type obtained at the second moment is inaccurate, then the road surface type is determined to be unreliable, and the wheel recognition fault is reported, and the instrument prompts an ABS braking system fault.

[0091] Further, in one embodiment, determining the target braking force based on the first optimal slip ratio includes:

[0092] Determining a maximum braking force corresponding to a first optimal slip ratio based on a preset mapping relationship between the slip ratio and the braking force;

[0093] The maximum braking force is used as the target braking force.

[0094] For example, in the embodiment of the present application, the mapping relationship between the preset slip rate and the braking force can be determined according to actual needs and is not limited here. For example, when the slip rate is X1, the corresponding braking force is Y1, when the slip rate is X2, the corresponding braking force is Y2, and when the slip rate is X3, the corresponding braking force is Y3, wherein the slip rate X1 < slip rate X2 < slip rate X3.

[0095] Specifically, since the identified road type has been determined to be credible, the first optimal slip ratio and the second optimal slip ratio are also accurate, so the braking force can be determined not only according to the first optimal slip ratio, but also according to the second optimal slip ratio, that is, the braking force can be determined according to the optimal slip ratio of the identified road type. According to the mapping relationship, the maximum braking force corresponding to the optimal slip ratio corresponding to the identified road type can be found, and the maximum braking force is the target braking force. It can be understood that, assuming that the target vehicle is traveling on a low-adhesion road surface, when the driver urgently steps on the brake pedal, the EMB system sends a braking request to the EMB wheel-end actuator according to the driver's intention input of stepping on the brake pedal. If the optimal slip rate corresponding to the wheel end on the low-adhesion road surface is X1, then the target braking force at this time is Y1, that is, the required deceleration or stopping effect is determined. At this time, the target clamping force Z1 can be determined according to the target braking force Y1, the effective radius of the brake disc of the target vehicle, and the wheel rolling radius of the target vehicle, and then the target clamping force Z1 is applied to the target vehicle to achieve the braking effect corresponding to the target braking force. In other words, the clamping force at this time no longer continues to increase according to the brake pedal input, but the braking effect is achieved by applying the target clamping force Z1 to achieve the braking effect corresponding to the target braking force Y1, thereby realizing the use of the maximum ground adhesion coefficient to quickly decelerate and stop the vehicle, thereby ensuring the driving safety of the user.

[0096] It can be understood that, assuming that the target vehicle is traveling on a high-adhesion road surface, when the driver urgently steps on the brake pedal, the EMB electronic mechanical wire control brake system sends a braking request to the EMB wheel-end actuator according to the driver's intention input of stepping on the brake pedal. If the optimal slip rate corresponding to the wheel end on the high-adhesion road surface is X2, then the target braking force at this time is Y2, that is, the required deceleration or stopping effect is determined. At this time, the target clamping force Z2 can be determined according to the target braking force Y2, the effective radius of the brake disc of the target vehicle, and the wheel rolling radius of the target vehicle, and then the target clamping force Z2 is applied to the target vehicle to achieve the braking effect corresponding to the target braking force. In other words, the clamping force at this time no longer continues to increase according to the brake pedal input, but the braking effect is achieved by applying the target clamping force Z2 to achieve the braking effect corresponding to the target braking force Y2, thereby utilizing the maximum ground adhesion coefficient to quickly decelerate and stop the vehicle to ensure the user's driving safety.

[0097] In a second aspect, an embodiment of the present application also provides a braking control system.

[0098] In one embodiment, referring to Figure 4 , Figure 4 This is a functional module diagram of the braking control system embodiment of the present application. Figure 4 As shown, the brake control system includes:

[0099] A first processing module, which is used to obtain a road type corresponding to a road surface currently located by the target vehicle, a first optimal slip ratio and a second optimal slip ratio corresponding to the target vehicle at different times, wherein the first optimal slip ratio is obtained based on an electronic mechanical wire control brake system, and the second optimal slip ratio is obtained based on an intelligent driving assistance system;

[0100] a second processing module, configured to determine a target braking force based on the first optimal slip ratio when it is determined that the road type is credible according to the first optimal slip ratio and the second optimal slip ratio;

[0101] A third processing module is configured to perform braking control based on the target braking force.

[0102] Furthermore, in one embodiment, the first processing module is specifically configured to:

[0103] Obtaining target parameters corresponding to the road surface on which the target vehicle is currently located, wherein the target parameters include front and rear suspension loads on the road surface, road braking force, and road slip rate;

[0104] The road surface type corresponding to the current road surface is determined based on the target parameters.

[0105] Furthermore, in one embodiment, the second processing module is specifically configured to:

[0106] Determining whether a difference between a first optimal slip ratio at the first moment and a second optimal slip ratio at the first moment is less than a preset first difference threshold;

[0107] If so, it is determined that the road surface type is credible;

[0108] If not, the credibility of the road surface type is determined based on the difference between the first optimal slip ratio at the second moment and the second optimal slip ratio at the second moment.

[0109] Furthermore, in one embodiment, the second processing module is further configured to:

[0110] determining whether a difference between the first optimal slip ratio at the second moment and the second optimal slip ratio at the second moment is less than a preset second difference threshold;

[0111] If so, it is determined that the road surface type is credible;

[0112] If not, the credibility of the road surface type is determined based on the difference between the first optimal slip ratio at the first moment and the first optimal slip ratio at the second moment.

[0113] Furthermore, in one embodiment, the second processing module is further configured to:

[0114] determining whether a difference between the first optimal slip ratio at the second moment and the first optimal slip ratio at the first moment is less than a preset third difference threshold;

[0115] If so, it is determined that the road surface type is credible;

[0116] If not, it is determined that the road surface type is unreliable and a wheel identification failure is reported.

[0117] Furthermore, in one embodiment, the third processing module is specifically used for:

[0118] Determining a maximum braking force corresponding to a first optimal slip ratio based on a preset mapping relationship between the slip ratio and the braking force;

[0119] The maximum braking force is used as the target braking force.

[0120] The present application obtains the road surface type corresponding to the road surface currently located by the target vehicle, the first optimal slip rate and the second optimal slip rate corresponding to the target vehicle at different times, the first optimal slip rate is obtained based on the electronic mechanical wire control brake system, and the second optimal slip rate is obtained based on the intelligent driving assistance system; when the road surface type is determined to be credible based on the first optimal slip rate and the second optimal slip rate, the target braking force is determined based on the first optimal slip rate; braking control is performed based on the target braking force, that is, the present application determines the accurate road surface type corresponding to the current road surface, so the first optimal slip rate corresponding to the road surface type is also accurate, and then the target braking force is obtained based on the first optimal slip rate, and finally the braking is controlled according to the target braking force, thereby avoiding the problem of wheel locking or excessive wheel speed reduction or increase caused by excessive braking caused by braking by pedaling.

[0121] Among them, the functional implementation of each module in the above-mentioned braking control system corresponds to the various steps in the above-mentioned braking control method embodiment, and its functions and implementation processes will not be repeated here one by one.

[0122] In a third aspect, an embodiment of the present application provides a brake control device, which may be a device with data processing function, such as a personal computer (PC), a laptop computer, or a server.

[0123] Reference Figure 5 , Figure 5 Schematic diagram of the hardware structure of the brake control device involved in the embodiment of the present application. In the embodiment of the present application, the brake control device may include a processor, a memory, a communication interface and a communication bus.

[0124] The communication bus may be of any type and is used to interconnect the processor, the memory, and the communication interface.

[0125] The communication interface includes input / output (I / O) interface, physical interface and logical interface, etc., which are used to realize the interconnection of devices inside the brake control device, and the interface used to realize the interconnection between the brake control device and other devices (such as other computing devices or user devices). The physical interface can be an Ethernet interface, a fiber optic interface, an ATM interface, etc.; the user device can be a display, a keyboard, etc.

[0126] The memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), etc.

[0127] The processor may be a general-purpose processor, which may call the brake control program stored in the memory and execute the brake control method provided by the embodiment of the present application. For example, the general-purpose processor may be a central processing unit (CPU). The method executed when the brake control program is called may refer to the various embodiments of the brake control method of the present application, which will not be described in detail here.

[0128] Those skilled in the art will understand that Figure 5 The hardware structure shown in the figure does not constitute a limitation on the present application, and may include more or less components than shown in the figure, or combine certain components, or arrange the components differently.

[0129] In a fourth aspect, an embodiment of the present application also provides a readable storage medium.

[0130] A braking control program is stored on the readable storage medium of the present application, wherein when the braking control program is executed by the processor, the steps of the braking control method as described above are implemented.

[0131] Among them, the method implemented when the braking control program is executed can refer to the various embodiments of the braking control method of the present application, and will not be repeated here.

[0132] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit "first", "second" and "third" to different types.

[0133] In the description of the embodiments of the present application, "exemplary", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "for example" or "for example" is intended to present related concepts in a specific way.

[0134] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; the “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0135] In some processes described in the embodiments of the present application, multiple operations or steps that appear in a specific order are included, but it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of the present application or in parallel, and the sequence number of the operation is only used to distinguish the different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed in sequence or in parallel, and these operations or steps may be combined.

[0136] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are only for description and do not represent the advantages or disadvantages of the embodiments.

[0137] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, disk, CD) as described above, and includes a number of instructions for a terminal device to execute the methods described in each embodiment of the present application.

[0138] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A braking control method, characterized in that: The braking control method comprises: Acquire a road type corresponding to a road surface currently located by the target vehicle, and a first optimal slip ratio and a second optimal slip ratio corresponding to the target vehicle at different times, wherein the first optimal slip ratio is acquired based on an electronic mechanical brake-by-wire system, and the second optimal slip ratio is acquired based on an intelligent driving assistance system; When it is determined that the road type is credible according to the first optimal slip ratio and the second optimal slip ratio, determining a target braking force based on the first optimal slip ratio; Braking control is performed based on the target braking force.

2. The braking control method according to claim 1, characterized in that: The step of obtaining the road surface type corresponding to the road surface on which the target vehicle is currently located includes: Obtaining target parameters corresponding to the road surface on which the target vehicle is currently located, wherein the target parameters include front and rear suspension loads on the road surface, road braking force, and road slip rate; The road surface type corresponding to the current road surface is determined based on the target parameters.

3. The braking control method according to claim 1, characterized in that: The first optimal slip ratio includes a first optimal slip ratio at a first moment corresponding to a first moment and a first optimal slip ratio at a second moment corresponding to a second moment, the second optimal slip ratio includes a first optimal slip ratio at a first moment corresponding to the first moment and a second optimal slip ratio at a second moment corresponding to the second moment, the first moment is earlier than the second moment, and before the step of determining that the road surface type is credible according to the first optimal slip ratio and the second optimal slip ratio, the method further includes: Determining whether a difference between a first optimal slip ratio at the first moment and a second optimal slip ratio at the first moment is less than a preset first difference threshold; If so, it is determined that the road surface type is credible; If not, the credibility of the road surface type is determined based on the difference between the first optimal slip ratio at the second moment and the second optimal slip ratio at the second moment.

4. The braking control method according to claim 3, characterized in that: The determining the credibility of the road type based on the difference between the first optimal slip ratio at the second moment and the second optimal slip ratio at the second moment comprises: determining whether a difference between the first optimal slip ratio at the second moment and the second optimal slip ratio at the second moment is less than a preset second difference threshold; If so, it is determined that the road surface type is credible; If not, the credibility of the road surface type is determined based on the difference between the first optimal slip ratio at the first moment and the first optimal slip ratio at the second moment.

5. The braking control method according to claim 4, characterized in that: The determining the credibility of the road type based on the difference between the first optimal slip ratio at the first moment and the first optimal slip ratio at the second moment comprises: determining whether a difference between the first optimal slip ratio at the second moment and the first optimal slip ratio at the first moment is less than a preset third difference threshold; If so, it is determined that the road surface type is credible; If not, it is determined that the road surface type is unreliable and a wheel identification failure is reported.

6. The brake control method according to claim 1, characterized in that: The determining of the target braking force based on the first optimal slip ratio includes: Determining a maximum braking force corresponding to a first optimal slip ratio based on a preset mapping relationship between the slip ratio and the braking force; The maximum braking force is used as the target braking force.

7. A braking control system, characterized in that: The brake control system comprises: A first processing module, which is used to obtain a road type corresponding to a road surface currently located by the target vehicle, a first optimal slip ratio and a second optimal slip ratio corresponding to the target vehicle at different times, wherein the first optimal slip ratio is obtained based on an electronic mechanical wire control brake system, and the second optimal slip ratio is obtained based on an intelligent driving assistance system; a second processing module, configured to determine a target braking force based on the first optimal slip ratio when it is determined that the road type is credible according to the first optimal slip ratio and the second optimal slip ratio; A third processing module is configured to perform braking control based on the target braking force.

8. The brake control system according to claim 7, characterized in that: The first processing module is specifically used for: Obtaining target parameters corresponding to the road surface on which the target vehicle is currently located, wherein the target parameters include front and rear suspension loads on the road surface, road braking force, and road slip rate; The road surface type corresponding to the current road surface is determined based on the target parameters.

9. A brake control device, characterized in that: The brake control device includes a processor, a memory, and a brake control program stored in the memory and executable by the processor, wherein when the brake control program is executed by the processor, the steps of the brake control method according to any one of claims 1 to 6 are implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a brake control program, wherein when the brake control program is executed by a processor, the steps of the brake control method according to any one of claims 1 to 6 are implemented.

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