Method and device for distributing EMB target braking force and medium

Abstract

The invention provides an EMB target braking force distribution method and device and a medium, and belongs to the technical field of vehicles. The method comprises the following steps: calculating a first distribution coefficient based on the vertical force of each wheel, and calculating a second distribution coefficient based on the slip rate; calculating a third distribution coefficient based on the slip rate change rate; determining a fourth distribution coefficient based on the deceleration of the whole vehicle; determining a fifth distribution coefficient based on the temperature of the brake disc; and according to the first distribution coefficient, the second distribution coefficient, the third distribution coefficient, the fourth distribution coefficient and the fifth distribution coefficient, the final braking force distribution coefficient of each wheel is determined. The braking force distribution coefficient is corrected in multiple dimensions, and the running stability and safety of the vehicle are guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicles, in particular to an EMB target braking force distribution method, device and medium. BACKGROUND

[0002] In the prior art, EMB can accurately control the braking torque independently for four wheels. However, the current EMB control strategy is mostly obtained by modifying the hydraulic system control strategy, and for braking force distribution, the traditional distribution method is equal distribution. The EMB template braking force distribution scheme has the following problems: the tire vertical force estimation dimension is single, cannot simultaneously reflect the longitudinal and lateral acceleration coupling effect, lacks forward-looking restriction on the dynamic change of the slip rate, the high slip rate wheel braking force is oversaturated, the rear wheel locking tendency under high braking intensity is not pre-inhibited, and the brake disc heat recession is not included in the distribution link, and the high temperature wheel continues to be under high load, which aggravates the performance decline. SUMMARY

[0003] The main purpose of the embodiments of the present application is to provide an EMB target braking force distribution method, device and medium, so as to realize multi-dimensional correction of the braking force distribution coefficient and ensure the driving stability and safety of the vehicle.

[0004] To achieve the above purpose, one aspect of the embodiments of the present application provides an EMB target braking force distribution method, which comprises: Obtaining the vertical load of each wheel, and calculating a first distribution coefficient based on the vertical force of each wheel according to the vertical load and the set vehicle mass; Obtaining the slip rate of each wheel, and correcting the braking force distribution according to the slip rate and the slip relationship between the slip rates of each wheel, to calculate a second distribution coefficient based on the slip rate; According to the slip rate, determining the slip rate change rate, and according to the slip relationship between the slip rate change rates of each wheel, calculating a third distribution coefficient based on the slip rate change rate; Obtaining the vehicle deceleration, and determining a fourth distribution coefficient based on the vehicle deceleration according to the proportional relationship between the vehicle deceleration and the braking of each wheel; Obtaining the brake disc temperature, and determining a fifth distribution coefficient based on the brake disc temperature according to the proportional relationship between the brake disc temperature and the braking force; According to the first distribution coefficient, the second distribution coefficient, the third distribution coefficient, the fourth distribution coefficient and the fifth distribution coefficient, determining the final braking force distribution coefficient of each wheel.

[0005] In some embodiments, the vertical load of each wheel is obtained, comprising: Obtaining the structural parameters, longitudinal acceleration and lateral acceleration of the current vehicle; Based on the structural parameters, longitudinal acceleration, and lateral acceleration, the vertical load of each wheel is obtained using the established vertical force calculation formula.

[0006] In some embodiments, calculating the first distribution coefficient based on the vertical force of each wheel includes: Maintain a consistent coefficient of adhesion for all wheels, ensuring that the braking force of the wheels is proportional to the braking force on the ground before the wheels lock up. Obtain the vehicle mass from the current vehicle's structural parameters, and based on the adhesion coefficient of each wheel, determine the first allocation coefficient according to the ratio of the vertical load to the vehicle mass.

[0007] In some embodiments, calculating the second allocation coefficient based on the slip ratio includes: Obtain the minimum threshold of the set slip ratio for each wheel, and determine the slip relationship between the slip ratios of each wheel based on the slip ratio; Based on the slip ratio and the set minimum slip ratio threshold, the minimum slip range of each wheel is determined, and based on the slip relationship between the minimum slip range and the slip ratio, the second allocation coefficient is determined.

[0008] In some embodiments, calculating the third allocation coefficient based on the rate of change of slip ratio includes: The current braking force of each wheel is obtained. When the current braking force is greater than the set braking force threshold and the front wheel threshold is greater than the rear wheel threshold, the slip ratio change rate is determined according to the slip ratio, and the negative slip ratio change rate is set to zero. Obtain the minimum threshold of the set change rate for each wheel, and determine the slip relationship between the slip rate change rates of each wheel based on the slip rate change rate. Based on the slip ratio change rate and the set minimum change rate threshold, the maximum change rate range of each wheel is determined, and based on the maximum change rate range and the slip relationship between the slip ratio change rates, the third allocation coefficient is determined.

[0009] In some embodiments, determining the fourth allocation coefficient based on the vehicle deceleration includes: Obtain the first functional relationship between braking force and vehicle deceleration; based on the first functional relationship, determine the fourth distribution coefficient of the front axle wheels using the proportional relationship between the front axle wheels and the vehicle deceleration. According to the first functional relationship, when the vehicle deceleration is in the set low deceleration range, the fourth distribution coefficient of the rear axle wheel is set to zero; when the vehicle deceleration is in the high deceleration range, the fourth distribution coefficient of the rear axle wheel is inversely proportional to the vehicle deceleration.

[0010] In some embodiments, determining the fifth distribution coefficient based on brake disc temperature includes: Obtain the second functional relationship between braking force and brake disc temperature. Based on the second functional relationship, when the brake disc temperature is within the set low temperature range, set the fifth distribution coefficient of each wheel to zero. Based on the second functional relationship, when the brake disc temperature is within the set high temperature range, the fifth distribution coefficient is inversely proportional to the brake disc temperature; wherein, the adjustment range of the fifth distribution coefficient of the front axle wheel is smaller than the adjustment range of the fifth distribution coefficient of the rear axle wheel.

[0011] In some embodiments, determining the final braking force distribution coefficient for each wheel includes: The set weighting coefficients for the vertical force, the slip ratio, the slip ratio change rate, the vehicle deceleration, and the brake disc temperature are obtained. The final braking force distribution coefficient for each wheel is determined based on the set weight coefficient, the first distribution coefficient, the second distribution coefficient, the third distribution coefficient, the fourth distribution coefficient, and the fifth distribution coefficient.

[0012] To achieve the above objectives, another aspect of the present application provides a vehicle control device, including a memory, a processor, and a program stored in the memory and executable on the processor, wherein the program, when executed by the processor, implements the above-described EMB target braking force distribution method.

[0013] To achieve the above objectives, another aspect of the embodiments of this application proposes a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method for allocating EMB target braking force.

[0014] The embodiments of this application include at least the following beneficial effects: This application provides a method, device, and medium for distributing EMB target braking force. This scheme distributes braking force based on a first distribution coefficient of the vertical force of each wheel, which can simultaneously reflect the coupling effect of longitudinal and lateral acceleration. Based on a second distribution coefficient based on the slip ratio and a third distribution coefficient based on the slip ratio change rate, the braking force distribution coefficient of wheels with high slip ratios is limited to ensure vehicle driving stability. Based on a fourth distribution coefficient based on the vehicle deceleration, the rear wheels are prevented from locking up when the braking intensity is high. Based on a fifth distribution coefficient based on the brake disc temperature, significant heat fade is avoided, thus improving efficiency. Attached Figure Description

[0015] Figure 1 This is a flowchart of the EMB target braking force distribution method provided in the embodiments of this application; Figure 2 This is a schematic diagram of the hardware structure framework of the vehicle control device provided in the embodiments of this application. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit it. In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with those of this application; they are merely examples of apparatuses and methods consistent with some aspects of the embodiments of this application as detailed in the appended claims.

[0017] It is understood that the terms "first," "second," etc., used in this application may be used to describe various concepts herein, but unless otherwise specified, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another. For example, without departing from the scope of embodiments of this application, Ethernet signaling information may also be referred to as interface signaling information, and similarly, interface signaling information may also be referred to as Ethernet signaling information. Depending on the context, the words "if" or "when" as used herein may be interpreted as "when," "in response to a determination," or "in the event of a determination."

[0018] As used in this application, the terms "at least one", "multiple", "each", "any", etc., "at least one" includes one, two or more, "multiple" includes two or more, "each" refers to each of the corresponding multiples, and "any" refers to any one of the multiples.

[0019] Unless otherwise defined, 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 application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0020] In some embodiments of one aspect of the present invention Figure 1 This is an optional flowchart of the EMB target braking force distribution method provided in the embodiments of this application. Figure 1 The method may include, but is not limited to, steps S100 to S600.

[0021] Step S100: Obtain the vertical load of each wheel, and calculate the first distribution coefficient based on the vertical force of each wheel according to the vertical load and the set vehicle mass.

[0022] Step S200: Obtain the slip ratio of each wheel, and correct the braking force distribution based on the slip ratio and the slip relationship between the slip ratios of each wheel, and calculate the second distribution coefficient based on the slip ratio.

[0023] Step S300: Determine the slip ratio change rate based on the slip ratio, and calculate the third distribution coefficient based on the slip ratio change rate according to the slip relationship between the slip ratio change rate and the slip ratio change rates of each wheel.

[0024] Step S400: Obtain the vehicle deceleration and determine the fourth distribution coefficient based on the ratio of the vehicle deceleration to the braking of each wheel.

[0025] Step S500: Obtain the brake disc temperature and determine the fifth distribution coefficient based on the brake disc temperature according to the ratio between brake disc temperature and braking force.

[0026] Step S600: Determine the final braking force distribution coefficient for each wheel based on the first distribution coefficient, the second distribution coefficient, the third distribution coefficient, the fourth distribution coefficient, and the fifth distribution coefficient.

[0027] Steps S100 to S600 as illustrated in this embodiment distribute braking force based on a first distribution coefficient of the vertical force of each wheel, which can simultaneously reflect the coupling effect of longitudinal and lateral acceleration. By using a second distribution coefficient based on the slip ratio and a third distribution coefficient based on the slip ratio change rate, the braking force distribution coefficient of wheels with high slip ratios is limited to ensure vehicle driving stability. By using a fourth distribution coefficient based on the vehicle deceleration, the tendency of the rear wheels to lock up under high braking intensity is avoided. By using a fifth distribution coefficient based on the brake disc temperature, large heat fade is avoided, thus improving efficiency.

[0028] In some embodiments of S100, the braking intensity of the entire vehicle is the sum and ratio of the coefficients of adhesion of each wheel. According to the sum and ratio theorem, when the coefficients of adhesion of each wheel are consistent, the braking intensity is equal to the coefficients of adhesion. Therefore, to improve the braking intensity of the entire vehicle, the coefficients of adhesion of each wheel should increase synchronously. When the coefficients of adhesion of each wheel are consistent, the coefficient of adhesion is the braking intensity. The goal of tire vertical force distribution is to ensure that the coefficients of adhesion of each wheel are consistent, so that the maximum braking intensity can be achieved regardless of the road surface adhesion.

[0029] Therefore, by obtaining the current vehicle's structural parameters, longitudinal acceleration, and lateral acceleration, and using the established vertical force calculation formula, the vertical load on each wheel can be obtained.

[0030] The first distribution factor is determined by the vertical load on each wheel and the total vehicle mass.

[0031] In some embodiments of S200, if the distribution relies solely on vertical force, this distribution method becomes highly dependent on the accuracy of the vertical force. Vertical force estimation is related to mass, center of mass position, longitudinal acceleration, and lateral acceleration; each of these factors can introduce a certain degree of error. Therefore, the braking force distribution still needs to be corrected based on the slip ratio.

[0032] Obtain the slip ratio of each wheel. A slip ratio of 0 indicates that the tire is rolling purely and has no tendency to lock up. A slip ratio of 1 indicates that the tire is sliding purely and is in a locked braking state.

[0033] By analyzing the slip ratios that influence each other between wheels, the slip relationship between slip ratios is obtained. Based on the slip relationship between slip ratios and the slip ratios themselves, the braking force distribution is corrected, and the second distribution coefficient is determined.

[0034] In some embodiments of S300, the rate of change of slip ratio may have a large error due to wheel speed fluctuations, but monitoring the rate of change of slip ratio can obtain the wheel's changing trend faster than monitoring slip ratio itself. Therefore, the rate of change of slip ratio can be considered simultaneously with slip ratio, accelerating the response speed to drastic changes in wheel speed.

[0035] Based on the slip ratio, when the current braking force on the wheel is large, the slip ratio change rate is determined. By observing the slip ratio change rates that influence each other between wheels, the slip relationship between the slip ratio change rates is obtained. Using the slip relationship between the slip ratio change rates and the slip ratio change rate, a third distribution coefficient is determined to make more precise corrections to the braking force distribution.

[0036] Since the rate of change of slip ratio is not linear, it should be taken as logarithm.

[0037] In some embodiments of the S400, during vehicle braking, the greater the deceleration, the more likely the rear wheels are to lock up. Rear wheel lockup can easily lead to vehicle instability, so it is important to avoid it. When the vehicle deceleration is large, the braking torque distributed to the rear axle should be reduced.

[0038] Obtain the vehicle deceleration, and determine the fourth distribution coefficient by the ratio of the vehicle deceleration to the braking of each wheel.

[0039] In some embodiments of S500, because brake disc thermal fade is not included in the distribution process, the high-temperature wheels continue to be under high load, exacerbating the performance decline. Therefore, the brake disc temperature of each wheel is obtained.

[0040] By analyzing the effect of brake disc temperature on wheel braking force, the proportional relationship between brake disc temperature and braking force is determined, thereby determining the fifth distribution coefficient.

[0041] In some embodiments of S600, the final braking force distribution coefficient for each wheel is determined by a first distribution coefficient, a second distribution coefficient, a third distribution coefficient, a fourth distribution coefficient, and a fifth distribution coefficient, so that braking force can be distributed using the final braking force distribution coefficient in the braking force distribution strategy.

[0042] In some embodiments of this invention, in S100, the calculation process of the first allocation coefficient includes: S110: Obtain the current vehicle's structural parameters, longitudinal acceleration, and lateral acceleration.

[0043] S120: Based on the structural parameters, current longitudinal acceleration, and current lateral acceleration, the vertical load of each wheel is obtained using the established vertical force calculation formula.

[0044] S130 maintains a consistent coefficient of adhesion for all wheels, ensuring that the braking force of the wheels is proportional to the braking force of the ground before wheel lock-up braking.

[0045] S140: Obtain the vehicle mass from the current vehicle's structural parameters, and determine the first distribution coefficient based on the utilization adhesion coefficient of each wheel and the ratio of vertical load to vehicle mass.

[0046] In this embodiment, the structural parameters of the current vehicle are obtained.

[0047] Structural parameters include: the longitudinal distance from the vehicle's center of gravity to the front axle. , rear axle longitudinal distance b, center of gravity height Front axle track Rear axle track The wheelbase L between the front and rear axles and the overall vehicle weight .

[0048] Obtain the longitudinal acceleration of the vehicle and lateral acceleration The vertical force is calculated using the established formula based on structural parameters, current longitudinal acceleration, and current lateral acceleration.

[0049]

[0050]

[0051]

[0052] The vertical load of each wheel is obtained. , , , (N). If each wheel utilizes a consistent coefficient of adhesion, then...

[0053] Before the wheels lock up, the braking force of the wheels can be considered to be proportional to the braking force on the ground. Therefore, the braking force of the wheels should be proportional to the vertical force of the tires. Based on the consistent use of the adhesion coefficient, the first distribution coefficient is determined by the ratio of the vertical load to the total vehicle mass.

[0054]

[0055] in, , , , This represents the braking force distribution coefficient calculated for each wheel based on the vertical force of the tire, i.e., the first distribution coefficient. The value of g is 9.81. .

[0056] In some embodiments of this invention, in step S200, the calculation process of the second allocation coefficient includes: S210: Obtain the minimum threshold of the set slip ratio for each wheel, and determine the slip relationship between the slip ratios of each wheel based on the slip ratio.

[0057] S220: Determine the minimum slip range of each wheel based on the slip ratio and the set minimum slip ratio threshold; determine the second distribution coefficient based on the slip relationship between the minimum slip range and the slip ratio.

[0058] In this embodiment, the minimum threshold for the set slip ratio of each wheel is obtained. , , , .

[0059] Based on the slip ratio of each wheel , , , To obtain the influence of the slip ratio of the current wheel on the other wheels, iterate through all wheels to obtain the slip ratio relationship between each wheel. .

[0060] in, This represents the effect of wheel j's slip ratio on wheel i. When i ≠ j, this value can be 0. However, considering the impact of the difference in braking force between coaxial wheels on opposite sides on vehicle stability, such as on split-plane roads, this value should be adjusted accordingly. , , , Increase. A slip ratio of 0 indicates that the tire is purely rolling and has no tendency to lock up, while a slip ratio of 1 indicates that the tire is purely sliding and will lock up.

[0061] By slip ratio , , , and the set minimum slip ratio threshold , , , Determine the minimum slip range of each wheel, and then determine the slip relationship between the minimum slip range and the slip ratio. Determine the second allocation coefficient.

[0062]

[0063] In the formula, , , , These represent the braking force distribution coefficients calculated based on the slip ratio for each wheel, i.e., the second distribution coefficients. Below the minimum threshold, control is not based on the slip ratio, and the distribution coefficient is 0.

[0064] In some embodiments of this invention, in step S300, the calculation process of the third allocation coefficient includes: S310: Obtain the current braking force of each wheel. When the current braking force is greater than the set braking force threshold and the front wheel threshold is greater than the rear wheel threshold, determine the slip ratio change rate based on the slip ratio and set the negative slip ratio change rate to zero.

[0065] S320: Obtain the minimum threshold of the set change rate for each wheel, and determine the slip relationship between the change rates of slip rates for each wheel based on the slip rate change rate.

[0066] S330: Based on the slip ratio change rate and the set minimum change rate threshold, determine the maximum change rate range for each wheel, and determine the third distribution coefficient based on the maximum change rate range and the slip relationship between the slip ratio change rates.

[0067] In this embodiment, the monitoring of the slip ratio change rate does not need to be carried out throughout the entire process. Therefore, the current braking force of each wheel is obtained, and it is determined whether there is a current braking force greater than the set braking force threshold and whether the front wheel threshold value is greater than the rear wheel threshold value.

[0068] If there exists a current braking force greater than the set braking force threshold, and the front wheel threshold is greater than the rear wheel threshold, then the slip ratio change rate is detected, and the slip ratio change rate is determined based on the slip ratio.

[0069] In other words, the braking force should be at the current wheel position. When it is large, that is At the same time, the front wheel threshold value should be greater than the rear wheel threshold value. In this embodiment, the front wheel threshold value can be the critical value of the front wheel angular deceleration or the critical value of the slip ratio, and the rear wheel threshold value can be the critical value of the rear wheel angular deceleration or the critical value of the slip ratio. The front wheel threshold value is generally set relatively high because the load on the front wheels increases during braking, requiring more braking force while maintaining steering capability. The rear wheel threshold value is usually set more strictly because the load on the rear wheels decreases during braking, making them more prone to lock-up, and rear wheel lock-up can lead to vehicle instability.

[0070] Furthermore, only positive values ​​of the slip ratio change are monitored; negative values ​​are treated as zero. Since the slip ratio change is not linear, it should be taken as logarithmically.

[0071] Obtain the minimum thresholds ds1_Thd, ds2_Thd, ds3_Thd, and ds4_Thd for each wheel, and determine the slip relationship between the slip ratio changes of each wheel based on the slip ratio change rate.

[0072] Based on the slip ratio change rates ds1, ds2, ds3, and ds4 of each wheel, the influence of the current wheel's slip ratio change rate on the other wheels is obtained. By iterating through all wheels, the slip relationship between the slip ratio change rates of each wheel is obtained. .

[0073] in, This represents the effect of the slip ratio change rate of wheel j on wheel i. When i ≠ j, this value can be 0. However, considering the impact of the difference in braking force between coaxial wheels on opposite sides on vehicle stability, such as on split-plane roads, this value should be adjusted accordingly. , , , Increase.

[0074] By using the slip ratio change rates ds1, ds2, ds3, ds4 and the set minimum change rate thresholds ds1_Thd, ds2_Thd, ds3_Thd, ds4_Thd, the minimum slip range of each wheel is determined. Then, the slip relationship between the minimum slip range and the slip ratio change rate is established. Determine the third allocation coefficient.

[0075]

[0076] In the formula, , , , These represent the braking force distribution coefficients calculated based on the slip ratio change rate for each wheel, i.e., the third distribution coefficients. When the slip ratio change rate is below the minimum threshold, the distribution coefficient is 0, as it is not based on slip ratio change rate control.

[0077] In some embodiments of this invention, in step S400, the calculation process of the fourth allocation coefficient includes: S410, obtain the first functional relationship between braking force and vehicle deceleration, and determine the fourth distribution coefficient of the front axle wheels based on the first functional relationship and the proportional relationship between the front axle wheels and the vehicle deceleration. S420, according to the first functional relationship, when the vehicle deceleration is in the set low deceleration range, the fourth distribution coefficient of the rear axle wheels is set to zero; when the vehicle deceleration is in the high deceleration range, the fourth distribution coefficient of the rear axle wheels is inversely proportional to the vehicle deceleration.

[0078] In this embodiment, during vehicle braking, the greater the deceleration, the more likely the rear wheels are to lock up. Rear wheel lockup can easily lead to vehicle instability, so it is important to avoid it. When the vehicle deceleration is large, the braking torque distributed to the rear axle should be reduced.

[0079] Obtain the first functional relationship between braking force and vehicle deceleration. 、 The first functional relationship represents the relationship between the braking force distribution coefficient obtained based on acceleration and the deceleration for the front and rear axles, respectively.

[0080]

[0081] In the formula, , , , This represents the braking force distribution coefficient for each wheel based on deceleration, i.e., the fourth distribution coefficient. To reduce the speed of the entire vehicle.

[0082] Specifically, for the front axle wheels, the corresponding coefficient should be 0 when the vehicle deceleration is in the set low deceleration range, and gradually increase according to the set increment when the vehicle deceleration is in the high deceleration range, being directly proportional to the vehicle deceleration. For the rear wheels, the corresponding coefficient should be 0 when the vehicle deceleration is in the set low deceleration range, and gradually decrease according to the set deceleration increment when the vehicle deceleration is in the set high deceleration range, being inversely proportional to the vehicle deceleration.

[0083] In other words, for the front wheels, the coefficient should be 0 when the deceleration is low, and gradually increase when the deceleration is high. For the rear wheels, the coefficient should be 0 when the deceleration is low, and gradually decrease when the deceleration is high.

[0084] In some embodiments of this invention, in step S500, the calculation process of the fifth allocation coefficient includes: S510, obtain the second functional relationship between braking force and brake disc temperature. Based on the second functional relationship, when the brake disc temperature is within the set low temperature range, set the fifth distribution coefficient of each wheel to zero. S520, based on the second functional relationship, when the brake disc temperature is within the set high temperature range, the fifth distribution coefficient is inversely proportional to the brake disc temperature; wherein, the adjustment range of the fifth distribution coefficient of the front axle wheels is smaller than the adjustment range of the fifth distribution coefficient of the rear axle wheels.

[0085] In this embodiment, brake fade is more severe when the disc temperature is too high, and the braking force should be reduced appropriately.

[0086] Obtain the second functional relationship between braking force and brake disc temperature. , The second functional relationship represents the relationship between the braking force distribution coefficient, obtained based on the brake disc temperature, and the brake disc temperature for both the front and rear axles.

[0087]

[0088] In the formula, , , , This represents the braking force distribution coefficient for each wheel based on the brake disc temperature. This refers to the brake disc temperature.

[0089] Specifically, when the brake disc temperature is within the set low temperature range, the corresponding coefficient should be 0; when the brake disc temperature is within the set high temperature range, the corresponding coefficient should decrease as the brake disc temperature rises, showing an inverse relationship with the brake disc temperature. For the front wheels, which provide the main braking force during braking, to avoid affecting braking strength, the adjustment range of the fifth distribution coefficient for the front axle wheels is smaller than that for the rear axle wheels.

[0090] In other words, the coefficient should be 0 when the brake disc temperature is low, and decrease as the brake disc temperature rises when the brake disc reaches a certain temperature, and this coefficient should have a minimum value. For the front wheels, which provide the main braking force during braking, to avoid affecting the braking strength, the decrease in the coefficient as the brake disc temperature rises should be less than that of the rear axle.

[0091] In some embodiments of this invention, in step S600, the calculation process for the final braking force distribution coefficient includes: S610, obtains the set weighting coefficients for vertical force, slip ratio, slip ratio change rate, vehicle deceleration, and brake disc temperature; S620 determines the final braking force distribution coefficient for each wheel based on the set weight coefficient, first distribution coefficient, second distribution coefficient, third distribution coefficient, fourth distribution coefficient, and fifth distribution coefficient.

[0092] In this embodiment, the set weighting coefficient for obtaining the vertical force is... The weighting coefficients for slip ratio The weighting coefficients for the rate of change of slip ratio The weighting coefficients for the overall vehicle deceleration And the weighting coefficient set for brake disc temperature .

[0093] Using the above allocation coefficients and set weight coefficients, and through the weighted calculation formula,

[0094] To obtain the final braking force distribution coefficient for each wheel. , , , . Indicates the left front wheel, Indicates the right front wheel, Indicates the left rear wheel, This indicates the right rear wheel.

[0095] Another embodiment of this application provides a vehicle control device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the above-described EMB target braking force distribution method. This vehicle control device can be any smart terminal, including a tablet computer, an in-vehicle computer, or similar device.

[0096] It is understood that the content of the above method embodiments is applicable to this device embodiment. The specific functions implemented by this device embodiment are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0097] Please see Figure 2 , Figure 2 The hardware structure of a vehicle control device according to another embodiment is illustrated. The vehicle control device includes: The processor can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to achieve the technical solutions provided in the embodiments of this application. The memory can be implemented in the form of read-only memory (ROM), static storage device, dynamic storage device, or random access memory (RAM). The memory can store the operating system and other applications. When the technical solutions provided in the embodiments of this specification are implemented through software or firmware, the relevant program code is stored in the memory and called by the processor to execute the EMB target braking force allocation method of the embodiments of this application. Input / output interfaces are used to implement information input and output; The communication interface is used to enable communication and interaction between this device and other devices. Communication can be achieved through wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.). A bus is used to transfer information between various components of a device, such as processors, memory, input / output interfaces, and communication interfaces. The processor, memory, input / output interfaces, and communication interfaces communicate with each other within the device via a bus.

[0098] This invention also provides a vehicle that includes the EMB target braking force distribution method described in the above embodiments.

[0099] The vehicle can be a private car, such as a sedan, SUV, MPV, or pickup truck. It can also be a commercial vehicle, such as a van, bus, small truck, or large semi-trailer. The vehicle must have an electric motor capable of outputting power or acting as a generator to store mechanical energy. When the vehicle is a new energy vehicle, it can be a hybrid or a pure electric vehicle.

[0100] Since the vehicle applies all the technical solutions of the above-described vehicle control device, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be repeated here.

[0101] Another embodiment of the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method for allocating the EMB target braking force.

[0102] It is understood that the content of the above method embodiments is applicable to this storage medium embodiment. The specific functions implemented in this storage medium embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments.

[0103] Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. Furthermore, memory may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, memory may optionally include memory remotely located relative to the processor, and these remote memories can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0104] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0105] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of this application, and may include more or fewer steps than shown, or combine certain steps, or different steps.

[0106] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0107] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0108] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, 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.

[0109] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0110] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0111] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0112] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.

Claims

1. A method for distributing the braking force of an EMB target, characterized in that, The method includes: Obtain the vertical load of each wheel, and calculate the first distribution coefficient based on the vertical force of each wheel according to the vertical load and the set total vehicle mass. The slip ratio of each wheel is obtained, and the braking force distribution is corrected according to the slip ratio and the slip relationship between the slip ratios of each wheel. A second distribution coefficient based on the slip ratio is calculated. Based on the slip ratio, the slip ratio change rate is determined, and based on the slip relationship between the slip ratio change rate and the slip ratio change rates of each wheel, a third allocation coefficient based on the slip ratio change rate is calculated. Obtain the vehicle deceleration, and determine a fourth distribution coefficient based on the vehicle deceleration and the braking ratio of each wheel. Obtain the brake disc temperature, and determine a fifth distribution coefficient based on the brake disc temperature according to the ratio between the brake disc temperature and the braking force. The final braking force distribution coefficient for each wheel is determined based on the first distribution coefficient, the second distribution coefficient, the third distribution coefficient, the fourth distribution coefficient, and the fifth distribution coefficient.

2. The method for distributing the EMB target braking force according to claim 1, characterized in that, The acquisition of the vertical load of each wheel includes: Obtain the current vehicle's structural parameters, longitudinal acceleration, and lateral acceleration; Based on the structural parameters, longitudinal acceleration, and lateral acceleration, the vertical load of each wheel is obtained using the established vertical force calculation formula.

3. The method for distributing EMB target braking force according to claim 1, characterized in that, The calculation of the first distribution coefficient based on the vertical force of each wheel includes: Maintain a consistent coefficient of adhesion for all wheels, ensuring that the braking force of the wheels is proportional to the braking force on the ground before the wheels lock up. Obtain the vehicle mass from the current vehicle's structural parameters, and based on the adhesion coefficient of each wheel, determine the first allocation coefficient according to the ratio of the vertical load to the vehicle mass.

4. The method for distributing the EMB target braking force according to claim 1, characterized in that, The calculation of the second allocation coefficient based on the slip ratio includes: Obtain the minimum threshold of the set slip ratio for each wheel, and determine the slip relationship between the slip ratios of each wheel based on the slip ratio; Based on the slip ratio and the set minimum slip ratio threshold, the minimum slip range of each wheel is determined, and based on the slip relationship between the minimum slip range and the slip ratio, the second allocation coefficient is determined.

5. The method for distributing the EMB target braking force according to claim 1, characterized in that, The calculation of the third allocation coefficient based on the rate of change of slip ratio includes: The current braking force of each wheel is obtained. When the current braking force is greater than the set braking force threshold and the front wheel threshold is greater than the rear wheel threshold, the slip ratio change rate is determined according to the slip ratio, and the negative slip ratio change rate is set to zero. Obtain the minimum threshold of the set change rate for each wheel, and determine the slip relationship between the slip rate change rates of each wheel based on the slip rate change rate. Based on the slip ratio change rate and the set minimum change rate threshold, the maximum change rate range of each wheel is determined, and based on the maximum change rate range and the slip relationship between the slip ratio change rates, the third allocation coefficient is determined.

6. The method for distributing the EMB target braking force according to claim 1, characterized in that, The determination of the fourth distribution coefficient based on the vehicle deceleration includes: Obtain the first functional relationship between braking force and vehicle deceleration; based on the first functional relationship, determine the fourth distribution coefficient of the front axle wheels using the proportional relationship between the front axle wheels and the vehicle deceleration. According to the first functional relationship, when the vehicle deceleration is in the set low deceleration range, the fourth distribution coefficient of the rear axle wheel is set to zero; when the vehicle deceleration is in the high deceleration range, the fourth distribution coefficient of the rear axle wheel is inversely proportional to the vehicle deceleration.

7. The method for distributing EMB target braking force according to claim 1, characterized in that, The determination of the fifth distribution coefficient based on brake disc temperature includes: Obtain the second functional relationship between braking force and brake disc temperature. Based on the second functional relationship, when the brake disc temperature is within the set low temperature range, set the fifth distribution coefficient of each wheel to zero. Based on the second functional relationship, when the brake disc temperature is within the set high temperature range, the fifth distribution coefficient is inversely proportional to the brake disc temperature; wherein, the adjustment range of the fifth distribution coefficient of the front axle wheel is smaller than the adjustment range of the fifth distribution coefficient of the rear axle wheel.

8. The method for distributing EMB target braking force according to claim 1, characterized in that, The determination of the final braking force distribution coefficient for each wheel includes: The set weighting coefficients for the vertical force, the slip ratio, the slip ratio change rate, the vehicle deceleration, and the brake disc temperature are obtained. The final braking force distribution coefficient for each wheel is determined based on the set weight coefficient, the first distribution coefficient, the second distribution coefficient, the third distribution coefficient, the fourth distribution coefficient, and the fifth distribution coefficient.

9. A vehicle control device, characterized in that, It includes a memory, a processor, and a program stored in the memory and executable on the processor, wherein the program, when executed by the processor, implements the EMB target braking force distribution method according to any one of claims 1 to 8.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the EMB target braking force distribution method according to any one of claims 1 to 8.

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