Braking method and device, readable storage medium and vehicle

Abstract

The invention provides a braking method and device, a readable storage medium and a vehicle, and is applied to the technical field of vehicles. The method comprises the following steps: determining a first braking force required by a first wheel in a front wheel and a rear wheel when the vehicle needs to be braked, and determining a second braking force required by a second wheel in the front wheel and the rear wheel according to a first braking force distribution curve between the front wheel and the rear wheel when the front wheel and the rear wheel are synchronously locked and the first braking force, and finally, the first wheel and the second wheel are braked according to the first braking force and the second braking force correspondingly. In the application, in the process of braking the vehicle, the distribution of the braking force on the front wheel and the rear wheel is close to the braking force distribution when the front wheel and the rear wheel are synchronously locked, so that when the vehicle is emergently braked, the time difference between the locking time of the front wheel and the locking time of the rear wheel can be shortened; therefore, the braking efficiency of the vehicle during emergency braking can be improved, the braking distance is shortened, and the safety of the vehicle is improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and more particularly, to a braking method, a device, a readable storage medium, and a vehicle in the field of vehicle technology. Background Art

[0002] Currently, vehicles generally use a braking force distribution coefficient to distribute braking force between the front and rear wheels. Specifically, when the driver depresses the brake pedal, the total braking force required by the vehicle is determined. The braking force required for the front wheels is then determined based on the total braking force and the front-wheel braking force distribution coefficient. The braking force required for the rear wheels is then determined based on the total braking force and the rear-wheel braking force distribution coefficient. Finally, the front wheels are braked based on the required front-wheel braking force, and the rear wheels are braked based on the required rear-wheel braking force.

[0003] The problem with the above method is that when the vehicle brakes suddenly, there may be a large time difference between the locking time of the front wheels and the locking time of the rear wheels, resulting in low braking efficiency and long braking distance during emergency braking, affecting the safety of the vehicle. Summary of the Invention

[0004] The present application provides a braking method, device, readable storage medium and vehicle, which can improve the safety of the vehicle during emergency braking.

[0005] In a first aspect, a braking method is provided, the method comprising:

[0006] determining a first braking force required by a first wheel when the vehicle needs to brake, the first wheel being one of a front wheel and a rear wheel of the vehicle;

[0007] determining a second braking force required for a second wheel based on a first braking force distribution curve and the first braking force, where the second wheel is the other of the front wheel and the rear wheel other than the first wheel, and the first braking force distribution curve is a relationship curve between the braking force of the front wheel and the braking force of the rear wheel when the front wheel and the rear wheel are synchronously locked;

[0008] The first wheel and the second wheel are braked according to the first braking force and the second braking force, respectively.

[0009] In an embodiment of the present application, when braking is required, a first braking force required for a first wheel among the front and rear wheels is determined. Based on the first braking force distribution curve between the front and rear wheels when the front and rear wheels are synchronously locked, and the first braking force, a second braking force required for a second wheel among the front and rear wheels is determined. Finally, the first wheel and the second wheel are braked based on the first braking force and the second braking force, respectively. In this way, during vehicle braking, the braking force distribution between the front and rear wheels can be made close to the braking force distribution when the front and rear wheels are synchronously locked. Consequently, in the event of emergency braking, the time difference between the locking time of the front and rear wheels can be shortened, thereby improving the braking efficiency of the vehicle during emergency braking, shortening the braking distance, and enhancing vehicle safety.

[0010] Optionally, after braking the first wheel and the second wheel according to the first braking force and the second braking force respectively, the method further includes: when one of the front wheel and the rear wheel is locked, increasing the braking force of a third wheel to a third braking force, and the third wheel is the one of the front wheel and the rear wheel that is not locked.

[0011] In an embodiment of the present application, when one of the front and rear wheels of a vehicle is locked and the other is not locked, the braking force of the non-locked wheel is increased. In this way, when the non-locked wheel locks, the time difference between the locking time of the front wheel and the locking time of the rear wheel can be reduced, thereby improving braking efficiency, shortening braking distance, and improving vehicle safety.

[0012] Optionally, before increasing the braking force of the third wheel to the third braking force, the method further includes: determining a fourth braking force, wherein the fourth braking force is greater than the braking force of the fourth wheel before locking, and the fourth wheel is one of the front wheel and the rear wheel that is locked; and determining the third braking force based on the fourth braking force and the first braking force distribution curve.

[0013] In the embodiment of the present application, a certain value is added to the braking force before the fourth wheel is locked to obtain the fourth braking force, and then the third braking force is determined based on the fourth braking force and the first braking force distribution curve. The braking force of the third wheel is increased to the third braking force, so that the braking force of the third wheel can be consistent with the first braking force distribution curve. In this way, when the non-locked wheels are locked, the time difference between the locking time of the front wheels and the locking time of the rear wheels can be reduced, thereby improving the braking efficiency, shortening the braking distance, and improving the safety of the vehicle.

[0014] Optionally, before determining the third braking force based on the fourth braking force and the first braking force distribution curve, the method further includes: determining at least one second braking force distribution curve from a plurality of braking force distribution curves, the plurality of braking force distribution curves corresponding one-to-one to a plurality of load levels, the first braking force distribution curve being a braking force distribution curve corresponding to a target load level among the plurality of braking force distribution curves, the target load level being a load level currently at which the vehicle is located, the second braking force distribution curve being a braking force distribution curve including a fifth braking force among the plurality of braking force distribution curves, the fifth braking force being a braking force corresponding to the fourth braking force in the braking force distribution curve, the fifth braking force being greater than the current braking force of the third wheel; and selecting one from the at least one second braking force distribution curve to replace the original first braking force distribution curve.

[0015] In the embodiment of the present application, in the process of increasing the braking force of the third wheel, at least one second braking force distribution curve is determined from a plurality of braking force distribution curves, and the third braking force is determined based on the fourth braking force and one of the second braking force distribution curves. This not only increases the braking force of the third wheel, but also makes the braking forces of the third and fourth wheels consistent with the braking force distribution curves. Further, when the non-locked wheels lock, the time difference between the locking time of the front wheels and the locking time of the rear wheels can be reduced, thereby improving braking efficiency, shortening the braking distance, and improving vehicle safety.

[0016] Optionally, selecting one from the at least one second braking force distribution curve to replace the original first braking force distribution curve includes: determining whether there are multiple second braking force distribution curves; if so, selecting one from the at least one second braking force distribution curve whose corresponding load level is adjacent to the target load level to replace the original first braking force distribution curve.

[0017] In an embodiment of the present application, when there are multiple second braking force distribution curves, one of the multiple second braking force distribution curves having a corresponding load level adjacent to the current load level of the vehicle is selected to replace the original first braking force distribution curve. This can improve the matching degree between the braking force of the wheel and the current load level of the vehicle, and thus can reduce the time difference between the locking time of the front wheels and the locking time of the rear wheels, thereby improving braking efficiency, shortening the braking distance, and improving vehicle safety.

[0018] Optionally, increasing the braking force of the third wheel to a third braking force includes: determining a slip rate deviation between a current slip rate of the third wheel and a critical slip rate; and when the slip rate deviation is less than a preset deviation threshold, increasing the braking force of the third wheel to the third braking force.

[0019] In this embodiment of the present application, when the fourth wheel is locked, if the slip ratio deviation between the third wheel's current slip ratio and the critical slip ratio is less than a preset deviation threshold, the braking force on the third wheel is increased to a third braking force. If the slip ratio deviation between the third wheel's current slip ratio and the critical slip ratio is greater than or equal to the preset deviation threshold, the braking force on the third wheel is not increased, thereby reducing unnecessary braking operations.

[0020] Optionally, after braking the first wheel and the second wheel according to the first braking force and the second braking force respectively, the method further includes: when no locked wheel appears among the front wheels and the rear wheels, determining whether there is a target wheel among the front wheels and the rear wheels whose slip rate reaches a critical slip rate; if so, increasing the braking force of other wheels among the front wheels and the rear wheels except the target wheel to increase the slip rate of the other wheels.

[0021] In an embodiment of the present application, when no locked wheel appears among the front wheels and the rear wheels, if it is determined that there is a target wheel among the front wheels and the rear wheels whose slip rate reaches the critical slip rate, the braking force of the wheels other than the target wheel is increased to increase the slip rate of the other wheels, which can increase the probability of multiple wheels locking at the same time, thereby improving the safety of the vehicle during emergency braking.

[0022] Optionally, the first braking force distribution curve is a nonlinear polynomial curve, the independent variable of the nonlinear polynomial curve is the first braking force, and the dependent variable is the second braking force.

[0023] In the embodiment of the present application, when the first braking force distribution curve is a nonlinear polynomial curve, the first braking force distribution curve is relatively simple. While accurately determining the second braking force based on the first braking force distribution, the difficulty of determining the second braking force based on the first braking force distribution curve can be reduced.

[0024] Optionally, each coefficient in the nonlinear polynomial curve corresponds to a current load level of the vehicle, and when the vehicle is at different load levels, each coefficient in the nonlinear polynomial curve is different.

[0025] In the embodiment of the present application, when the coefficients in the nonlinear polynomial curve correspond to the vehicle's current load level, the braking force distribution curve can be matched to the vehicle's load state. Furthermore, when determining the second braking force based on the first braking force distribution curve, the relationship between the second braking force and the first braking force can be made consistent with the first braking force distribution curve. Consequently, when braking the front and rear wheels of the vehicle based on the first and second braking forces, the time difference between the locking time of the front and rear wheels can be reduced or even eliminated during emergency braking, thereby improving braking efficiency, shortening braking distance, and enhancing vehicle safety.

[0026] In a second aspect, a braking device is provided, comprising:

[0027] a first determining module, configured to determine a first braking force required by a first wheel when the vehicle needs to brake, the first wheel being one of a front wheel and a rear wheel of the vehicle;

[0028] a second determining module, configured to determine a second braking force required for a second wheel based on a first braking force distribution curve and the first braking force, where the second wheel is the other of the front wheel and the rear wheel other than the first wheel, and the first braking force distribution curve is a relationship curve between the braking force of the front wheel and the braking force of the rear wheel when the front wheel and the rear wheel are synchronously locked;

[0029] A braking module is configured to brake the first wheel and the second wheel according to the first braking force and the second braking force respectively.

[0030] According to a third aspect, an electronic device is provided, the device comprising:

[0031] a memory for storing executable program code;

[0032] A processor is used to call and run the executable program code from the memory, so that the electronic device executes the method in any possible implementation manner of the first aspect above.

[0033] In a fourth aspect, a program product is provided, comprising: a program code, which, when executed on an electronic device, causes the electronic device to execute the method in any possible implementation of the first aspect.

[0034] In a fifth aspect, a readable storage medium is provided, which stores a program code. When the program code is run on an electronic device, the electronic device executes the method in any possible implementation manner of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1This is a schematic diagram of braking force distribution of a vehicle provided in an embodiment of the present application;

[0036] Figure 2 This is a flowchart of the steps of a braking method provided in an embodiment of the present application;

[0037] Figure 3 This is a schematic diagram of braking force distribution of another vehicle provided in an embodiment of the present application;

[0038] Figure 4 This is a schematic flow chart of a braking method provided in an embodiment of the present application;

[0039] Figure 5 This is a schematic structural diagram of a braking device provided in an embodiment of the present application;

[0040] Figure 6 It is a structural diagram of a device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0041] The following will clearly and thoroughly describe the technical solutions in this application in conjunction with the accompanying drawings. In the description of the embodiments of this application, unless otherwise specified, " / " means or, for example, A / B can mean A or B: "and / or" in the text is only a description of the association relationship of associated objects, indicating that there can be three relationships, 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 this application, "multiple" means two or more than two.

[0042] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood to imply or suggest relative importance or implicitly indicate the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0043] Currently, vehicles generally use a braking force distribution coefficient to distribute braking force between the front and rear wheels. When this method is used, the front and rear wheels will not lock simultaneously during emergency braking on most road surfaces. Instead, there may be a significant time difference between the front and rear wheels locking. A larger time difference results in lower braking efficiency, longer stopping distances, and reduced vehicle safety.

[0044] See also Figure 1 , Figure 1 This is a schematic diagram of the braking force distribution of a vehicle provided in an embodiment of the present application. Figure 1The horizontal axis represents the braking force on the vehicle's front wheels, and the vertical axis represents the braking force on the vehicle's rear wheels. Both axes are expressed in Newtons (N). Curve 11 shows the relationship between the front and rear wheel braking forces when the vehicle is fully loaded and the front and rear wheels are synchronously locked. Curve 12 shows the relationship between the front and rear wheel braking forces when the vehicle is unloaded. Curve 13 shows the relationship between the front and rear wheel braking forces when the braking force is distributed between the front and rear wheels using the braking force distribution coefficient.

[0045] Curves 11 and 13 intersect at point A. Therefore, if the vehicle is fully loaded and the braking force on the front wheels is equal to the horizontal coordinate of point A and the braking force on the rear wheels is equal to the vertical coordinate of point A, then both the front and rear wheels may lock simultaneously during emergency braking. At other points, however, both the front and rear wheels will not lock simultaneously during emergency braking. Similarly, curves 12 and 13 intersect at point B. Therefore, if the vehicle is unloaded and the braking force on the front wheels is equal to the horizontal coordinate of point B and the braking force on the rear wheels is equal to the vertical coordinate of point B, then both the front and rear wheels may lock simultaneously during emergency braking. At other points, both the front and rear wheels will not lock simultaneously during emergency braking.

[0046] In practical applications, experiments can be conducted to measure the front and rear wheel braking forces when the fully loaded vehicle is subjected to emergency braking on roads with different adhesion coefficients. This yields multiple sets of data. Each set of data corresponds to a road surface with a different adhesion coefficient and includes the front and rear wheel braking forces when the front and rear wheels are locked simultaneously. Curve 11 is then fitted using the front wheel braking force in each set of data as the X-axis coordinate and the rear wheel braking force as the Y-axis coordinate.

[0047] Similarly, experiments can be conducted to measure the front and rear wheel braking forces during emergency braking on roads with different adhesion coefficients while the vehicle is unloaded, generating multiple sets of data. Each set of data corresponds to a road surface with a different adhesion coefficient and includes the front and rear wheel braking forces during synchronous locking. Curve 12 is then fitted using the front wheel braking force in each set of data as the X-axis coordinate and the rear wheel braking force as the Y-axis coordinate.

[0048] It should be noted that in the process of fitting the braking force distribution curve, the braking force of the front wheel can be used as the Y-axis coordinate and the braking force of the rear wheel can be used as the X-axis coordinate, and the braking force distribution curve can be obtained by fitting multiple sets of data.

[0049] In order to reduce the time difference between the front and rear wheels when they are locked, an embodiment of the present application provides a braking method, which can be executed by an electronic control unit (ECU) in an electronic mechanical brake (EMB) included in a vehicle.

[0050] See also Figure 2 , Figure 2 This is a flowchart of a braking method provided in an embodiment of the present application. The method includes the following steps:

[0051] Step 201: Determine a first braking force required by a first wheel when the vehicle needs to brake.

[0052] The first wheel is one of the front and rear wheels of the vehicle, and the other of the front and rear wheels is the second wheel. For example, when the front wheel is selected as the first wheel, the rear wheel is the second wheel; when the rear wheel is selected as the first wheel, the front wheel is the second wheel. The first braking force is the braking force required by the first wheel when the vehicle's brake pedal is depressed.

[0053] Exemplarily, the ECU is connected to a displacement sensor that detects the displacement of the brake pedal. When the vehicle is in motion and the driver depresses the brake pedal, the ECU can detect the displacement of the brake pedal via the displacement sensor. The ECU then determines the first braking force required for the first wheel based on the detected brake pedal displacement, the vehicle's current state, and the road conditions, using a preset control algorithm. The first braking force is positively correlated with the displacement of the brake pedal. It should be understood that the method by which the ECU determines the first braking force required for the first wheel based on the displacement of the brake pedal can be customized as needed and is not limited in this embodiment.

[0054] Step 202: Determine a second braking force required by a second wheel according to the first braking force distribution curve and the first braking force.

[0055] The first braking force distribution curve represents the relationship between the front and rear wheel braking forces when the front and rear wheels are locked synchronously. The second braking force represents the braking force applied to the second wheel when the brake pedal is depressed. The sum of the first and second braking forces is the total braking force applied to the vehicle.

[0056] For example, the first braking force distribution curve may be a curve showing the relationship between the braking force of the front wheels and the braking force of the rear wheels when the front wheels and the rear wheels are locked synchronously when the vehicle is in a fully loaded state, for example Figure 1Alternatively, the first braking force distribution curve may be a curve showing the relationship between the braking force of the front wheels and the braking force of the rear wheels when the front wheels and the rear wheels are locked synchronously when the vehicle is in an unloaded state, for example Figure 1 The first braking force distribution curve may also be a curve showing the relationship between the front wheel braking force and the rear wheel braking force when the front and rear wheels are locked synchronously, when the vehicle is not fully loaded, unloaded, or in other load states.

[0057] In one embodiment, a curve in the above example can be pre-set as the first braking force distribution curve. After determining the first braking force, the first braking force can be substituted into the first braking force distribution curve to obtain the second braking force. Figure 1 The curve 11 shown is a first braking force distribution curve, and the formula (1) corresponding to the curve 11 is shown below.

[0058] y = 5 × 10 -10 x 3 -4×10 -5 x 2 +0.81x+71.95 (1);

[0059] In this case, the first braking force is x in formula (1), and y in formula (1) is the second braking force. After determining the first braking force x, the ECU can substitute the first braking force x into the corresponding formula (1) to calculate the second braking force y. At this time, the first braking force of the front wheel (i.e., the first wheel) and the second braking force of the rear wheel (i.e., the second wheel) are both determined.

[0060] Similarly, you can also pre-set Figure 1 The curve 12 shown is a first braking force distribution curve, and the formula (2) corresponding to the curve 12 is shown below.

[0061] y=6×10 -10 x 3 -4×10 -5 x 2 +0.69x+50.61 (2);

[0062] In this case, the first braking force is x in formula (2), and y in formula (2) is the second braking force. After determining the first braking force x, the ECU can substitute the first braking force x into the corresponding formula (2) to calculate the second braking force y. At this time, the first braking force of the front wheel (i.e., the first wheel) and the second braking force of the rear wheel (i.e., the second wheel) are both determined.

[0063] It should be understood that when the rear wheel is selected as the first wheel and the front wheel as the second wheel, after determining the braking force of the rear wheel (i.e., the first braking force), the braking force of the front wheel (i.e., the second braking force) can be determined by the braking force of the rear wheel and the first braking force distribution curve.

[0064] Step 203: Brake the first wheel and the second wheel according to the first braking force and the second braking force respectively.

[0065] Exemplarily, the EMB includes a left front brake motor, a left front retarder and a left front brake actuator corresponding to the left front wheel among the front wheels, a right front brake motor, a right front retarder and a right front brake actuator corresponding to the right front wheel among the front wheels, and also includes a left rear brake motor, a left rear retarder and a left rear brake actuator corresponding to the left rear wheel among the rear wheels, and a right rear brake motor, a right rear retarder and a right rear brake actuator corresponding to the right rear wheel among the rear wheels.

[0066] When the first wheel is the front wheel and the second wheel is the rear wheel, after determining the first braking force and the second braking force, the ECU converts the first braking force into control signals corresponding to the left front brake motor and the right front brake motor, and controls the operation of the left front brake motor and the right front brake motor through the control signals. The left front brake motor drives the left front brake actuator to operate through the left front retarder, and the right front brake motor drives the right front brake actuator to operate through the right front retarder, so as to apply the first braking force to the left front wheel and the right front wheel for braking.

[0067] At the same time, the ECU converts the second braking force into control signals corresponding to the left rear brake motor and the right rear brake motor, and controls the operation of the left rear brake motor and the right rear brake motor through the control signals. The left rear brake motor drives the left rear brake actuator through the left rear reducer, and the right rear brake motor drives the right rear brake actuator through the right rear reducer to apply the second braking force to the left and right rear wheels for braking.

[0068] It should be understood that the above are merely illustrative examples, and the method of braking the first wheel according to the first braking force and braking the second wheel according to the second braking force may include but is not limited to the above examples.

[0069] In an embodiment of the present application, when braking is required, a first braking force required for a first wheel among the front and rear wheels is determined. Based on the first braking force distribution curve between the front and rear wheels when the front and rear wheels are synchronously locked, and the first braking force, a second braking force required for a second wheel among the front and rear wheels is determined. Finally, the first wheel and the second wheel are braked based on the first braking force and the second braking force, respectively. In this way, during vehicle braking, the braking force distribution between the front and rear wheels can be made close to the braking force distribution when the front and rear wheels are synchronously locked. Consequently, in the event of emergency braking, the time difference between the locking time of the front and rear wheels can be shortened, thereby improving the braking efficiency of the vehicle during emergency braking, shortening the braking distance, and enhancing vehicle safety.

[0070] like Figure 1 As shown, when curve 11 is used as the first braking force distribution curve, during each braking operation, the braking forces distributed on the front wheels and the braking forces distributed on the rear wheels lie on curve 11, and the relationship between the braking forces on the front wheels and the rear wheels is consistent with curve 11. When an emergency braking force is applied, the locking time of the front wheels is close to or the same as that of the rear wheels, and the time difference between the locking times of the front and rear wheels is greatly shortened. This can improve the braking efficiency of the vehicle during emergency braking, shorten the braking distance, and enhance vehicle safety.

[0071] Optionally, before determining the second braking force required by the second wheel according to the first braking force distribution curve and the first braking force, the method may further include:

[0072] Determining a current target load level of the vehicle from a plurality of load levels, wherein the plurality of load levels correspond one to one with a plurality of braking force distribution curves;

[0073] A first braking force distribution curve corresponding to the target load level is determined from the plurality of braking force distribution curves.

[0074] In one embodiment, the vehicle's load state can be divided into multiple load levels in ascending order based on the vehicle's load capacity, and the braking force distribution curves for the vehicle at different load levels can be pre-determined through experiments. During vehicle operation, the ECU can select, based on the vehicle's current load level (i.e., target load level), a braking force distribution curve from the multiple load levels that matches the target load level as a first braking force distribution curve, thereby matching the first braking force distribution curve with the vehicle's current load state.

[0075] For example, the vehicle load state may be divided into five load levels in ascending order in the manner shown in Table 1.

[0076] Load level Load state Suspension height Tire pressure change Level 1 —— Initial suspension height Initial tire Level 2 25% of load + empty Height change h1 Tire pressure change P1 Level 3 50% load + empty Height change h2 Tire pressure change P2 Level 4 75% load + empty Height change h3 Tire pressure change P3 Level 5 100% loaded + empty —— ——

[0077] Table 1

[0078] As shown in Table 1, the load levels are Level 1 (also known as unloaded), Level 2 (also known as light load), Level 3 (also known as medium load), Level 4 (also known as heavy load), and Level 5 (also known as fully loaded). The vehicle load increases from Level 1 to Level 5. Level 1 corresponds to an unloaded state; Level 2 corresponds to a load greater than the unloaded state and less than or equal to 25% of the maximum load; Level 3 corresponds to a load greater than 25% of the maximum load and less than or equal to 50% of the maximum load; Level 4 corresponds to a load greater than 50% of the maximum load and less than or equal to 75% of the maximum load; and Level 5 corresponds to a load greater than 75% of the maximum load.

[0079] See also Figure 3 , Figure 3 This is a schematic diagram of the braking force distribution of another vehicle provided in an embodiment of the present application. In practical applications, the braking force distributed on the front wheels and the braking force distributed on the rear wheels when the front and rear wheels are synchronously locked can be measured experimentally when the vehicle is in an unloaded state and emergency braking is performed on multiple road surfaces with different adhesion coefficients, thereby obtaining multiple sets of data. Each set of data corresponds to a road surface with a different adhesion coefficient and includes the braking force distributed on the front wheels and the braking force distributed on the rear wheels when the front and rear wheels are synchronously locked. Subsequently, the braking force distribution curve 31 is obtained by fitting, using the braking force of the front wheels in each set of data as the X-axis coordinate and the braking force of the rear wheels as the Y-axis coordinate. The braking force distribution curve 31 corresponds to level 1.

[0080] Similarly, experimental measurements can be conducted to determine the front and rear wheel braking forces when the vehicle's load is greater than its unladen load and less than or equal to 25% of its maximum load, during emergency braking on roads with different adhesion coefficients. This yields multiple sets of data. Each set of data corresponds to a road surface with a different adhesion coefficient and includes the front and rear wheel braking forces when the front and rear wheels are locked simultaneously. Subsequently, a braking force distribution curve 32 is obtained by fitting the front wheel braking force in each data set as the X-axis coordinate and the rear wheel braking force as the Y-axis coordinate. Braking force distribution curve 32 corresponds to level 2.

[0081] Similarly, experimental measurements can be conducted to determine the front and rear wheel braking forces when the vehicle's load is greater than 25% and less than or equal to 50% of the maximum load, during emergency braking on roads with different adhesion coefficients. This yields multiple sets of data. Each set of data corresponds to a road surface with a different adhesion coefficient and includes the front and rear wheel braking forces when the front and rear wheels are locked simultaneously. Subsequently, a braking force distribution curve 33 is fitted, using the front wheel braking force in each set of data as the X-axis coordinate and the rear wheel braking force as the Y-axis coordinate. Braking force distribution curve 33 corresponds to level 3.

[0082] Similarly, experimental measurements can be conducted to determine the front and rear wheel braking forces when the vehicle's load is greater than 50% and less than or equal to 75% of its maximum load, during emergency braking on roads with different adhesion coefficients. This yields multiple sets of data. Each set of data corresponds to a road surface with a different adhesion coefficient and includes the front and rear wheel braking forces when the front and rear wheels are locked simultaneously. Subsequently, a braking force distribution curve 34 is fitted, using the front wheel braking force in each set of data as the X-axis coordinate and the rear wheel braking force as the Y-axis coordinate. Braking force distribution curve 34 corresponds to level 4.

[0083] Similarly, experimental measurements can be conducted to determine the front and rear wheel braking force distributions when the front and rear wheels simultaneously lock, with the vehicle's load exceeding 75% of the maximum load. This yields multiple data sets. Each data set corresponds to a road surface with a specific adhesion coefficient and includes the front and rear wheel braking force distributions when the front and rear wheels simultaneously lock. Subsequently, a braking force distribution curve 35 is fitted, using the front wheel braking force in each data set as the X-axis coordinate and the rear wheel braking force as the Y-axis coordinate. This braking force distribution curve 35 corresponds to level 5.

[0084] In one embodiment, the height of the vehicle suspension when the vehicle is in an unloaded state (this height is the initial suspension height) can be experimentally measured; and the suspension height change h1 when the vehicle load is 25% of the maximum load is measured; and the suspension height change h2 when the vehicle load is 50% of the maximum load is measured; and the suspension height change h3 when the vehicle load is 75% of the maximum load is measured.

[0085] After being started, the ECU can obtain the current suspension height of the vehicle, calculate the height difference between the current suspension height and the initial suspension height, and obtain the height change. When the height change is close to or equal to 0, the target load level of the vehicle is determined to be level 1. When the current suspension height is less than the initial suspension height and the height change is less than or equal to h1, the target load level of the vehicle is determined to be level 2. When the current suspension height is less than the initial suspension height, and the height change is greater than h1 and less than or equal to h2, the target load level of the vehicle is determined to be level 3. When the current suspension height is less than the initial suspension height, and the height change is greater than h2 and less than or equal to h3, the target load level of the vehicle is determined to be level 4. When the current suspension height is less than the initial suspension height, and the height change is greater than h3, the target load level of the vehicle is determined to be level 5.

[0086] In another embodiment, the tires of the vehicle when the vehicle is in an unloaded state (the tires are initial tires) can be experimentally measured; and the tire pressure change P1 when the vehicle's load is 25% of the maximum load can be measured; and the tire pressure change P2 when the vehicle's load is 50% of the maximum load can be measured; and the tire pressure change P3 when the vehicle's load is 75% of the maximum load can be measured.

[0087] After being started, the ECU can obtain the current tire pressure of the vehicle. The current tire pressure can be the average of the tire pressures of all wheels or the maximum value of the tire pressures of all wheels. Then, the tire pressure difference between the current tire pressure and the initial tire pressure is calculated to obtain the tire pressure change. When the tire pressure change is close to or equal to 0, the vehicle's load level is determined to be level 1. When the current tire pressure is greater than the initial tire pressure and the tire pressure change is less than or equal to P1, the vehicle's target load level is determined to be level 2. When the current tire pressure is greater than the initial tire pressure, and the tire pressure change is greater than P1 and less than or equal to P2, the vehicle's target load level is determined to be level 3. When the current tire pressure is greater than the initial tire pressure, and the tire pressure change is greater than P2 and less than or equal to P3, the vehicle's target load level is determined to be level 4. When the current tire pressure is greater than the initial tire pressure, and the tire pressure change is greater than P3, the vehicle's target load level is determined to be level 5.

[0088] In another embodiment, the target load level can be determined by combining the current suspension height and current tire pressure. Referring to the above example, after being activated, the ECU can obtain the vehicle's current tire pressure, calculate the tire pressure change based on the current tire pressure, and determine a first load level based on the tire pressure change. Simultaneously, the ECU can obtain the current suspension height, calculate the height change based on the current suspension height, and determine a second load level based on the height change. The maximum of the first and second load levels is then selected as the target load level.

[0089] After determining the target load level of the vehicle, a first braking force distribution curve corresponding to the target load level is determined from the plurality of braking force distribution curves. For example, when the target load level is determined to be level 1, the first braking force distribution curve may be determined to be Figure 3 The braking force distribution curve 31 shown in FIG. 3 can be determined as follows when the target load level is determined to be level 3: Figure 3 Braking force distribution curve 33 is shown.

[0090] After determining the first braking force distribution curve, when it is detected that the brake pedal is depressed, the first braking force required by the first wheel can be determined, and then the second braking force required by the second wheel can be determined based on the first braking force distribution curve and the first braking force. Finally, the first wheel is braked according to the first braking force, and the second wheel is braked according to the second braking force.

[0091] It should be understood that Table 1 only shows one method of classifying load levels. The methods of classifying load levels may include but are not limited to Figure 1 shown.

[0092] In an embodiment of the present application, the vehicle's load state is divided into multiple load levels, and a corresponding braking force distribution curve is set for each load level. During vehicle operation, the braking force distribution curve corresponding to the vehicle's current load level is selected, thereby matching the braking force distribution curve with the vehicle's load state. Furthermore, when determining the second braking force based on the braking force distribution curve, the relationship between the second braking force and the first braking force can be made consistent with the braking force distribution curve. Consequently, when braking the front and rear wheels of the vehicle based on the first and second braking forces, the time difference between the locking time of the front and rear wheels can be reduced or even eliminated in the event of emergency braking, thereby improving braking efficiency, shortening braking distance, and enhancing vehicle safety.

[0093] Optionally, the first braking force distribution curve is a nonlinear polynomial curve, the independent variable of the nonlinear polynomial curve is the first braking force, and the dependent variable is the second braking force.

[0094] In conjunction with the above example, the first braking force distribution curve can be a nonlinear polynomial curve, specifically a cubic polynomial curve of one variable as shown in the above formulas (1) and (2). Of course, it can also be a quartic polynomial curve of one variable or a higher-order polynomial curve, and this embodiment does not impose any restrictions on this. For example, in the nonlinear polynomial curves of formulas (1) and (2), the dependent variable (x) is the first braking force, and the independent variable (y) is the second braking force.

[0095] In the embodiment of the present application, when the first braking force distribution curve is a nonlinear polynomial curve, the first braking force distribution curve is relatively simple. While accurately determining the second braking force based on the first braking force distribution, the difficulty of determining the second braking force based on the first braking force distribution curve can be reduced.

[0096] Optionally, each coefficient in the nonlinear polynomial curve corresponds to the current load level of the vehicle. When the vehicle is at different load levels, the each coefficient in the nonlinear polynomial curve is different.

[0097] Combined with Table 1 and Figure 3 As shown, the vehicle load level can be divided into multiple load levels. For each load level, the load level can be calibrated by experiment as follows: Figure 3 The various braking force distribution curves (i.e. nonlinear polynomial curves) shown in FIG. Figure 3 Among the multiple braking force distribution curves shown, different braking force distribution curves correspond to different load levels, and the coefficients in the different braking force distribution curves are different.

[0098] Taking the above formula (1) and formula (2) as examples, the coefficient of the third-order term in formula (1) is different from the coefficient of the third-order term in formula (2), the coefficient of the second-order term in formula (1) is different from the coefficient of the second-order term in formula (2), the coefficient of the first-order term in formula (1) is different from the coefficient of the first-order term in formula (2), and the constant term in formula (1) is also different from the constant term in formula (2).

[0099] In the embodiment of the present application, when the coefficients in the nonlinear polynomial curve correspond to the vehicle's current load level, the braking force distribution curve can be matched to the vehicle's load state. Furthermore, when determining the second braking force based on the first braking force distribution curve, the relationship between the second braking force and the first braking force can be made consistent with the first braking force distribution curve. Consequently, when braking the front and rear wheels of the vehicle based on the first and second braking forces, the time difference between the locking time of the front and rear wheels can be reduced or even eliminated during emergency braking, thereby improving braking efficiency, shortening braking distance, and enhancing vehicle safety.

[0100] Optionally, after braking the first wheel and the second wheel according to the first braking force and the second braking force respectively, the method may further include:

[0101] When one of the front wheels and the rear wheels is locked, the braking force of the third wheel is increased to a third braking force, where the third wheel is the one of the front wheels and the rear wheels that is not locked.

[0102] For example, after a first braking force is applied to the first wheel and a second braking force is applied to the second wheel, the slip rates of the left front wheel and the right front wheel, as well as the slip rates of the left rear wheel and the right rear wheel, can be obtained. After obtaining the slip rates of each wheel, if the slip rate of the left front wheel is greater than or equal to a preset slip rate threshold and / or the slip rate of the right front wheel is greater than or equal to a preset slip rate threshold, and the slip rates of the left rear wheel and the right rear wheel are both less than the slip rate threshold, it can be determined that the front wheels are locked, but the rear wheels are not locked, and the third wheel can be determined to be a rear wheel, and the front wheel can be determined to be the fourth wheel.

[0103] Similarly, after obtaining the slip rate of each wheel, if the slip rate of the left rear wheel is greater than or equal to the preset slip rate threshold and / or the slip rate of the right rear wheel is greater than or equal to the preset slip rate threshold, and the slip rate of the left front wheel and the slip rate of the right front wheel are both less than the slip rate threshold, then it can be determined that the rear wheels are locked and the front wheels are not locked, so the third wheel can be determined to be the front wheel, and the rear wheel can be determined to be the fourth wheel.

[0104] After determining that one of the front and rear wheels is locked and the other is not locked, the current braking force of the third wheel that is not locked may be increased to a third braking force. For example, if the first wheel is a front wheel and the second wheel is a rear wheel, and if it is determined that the front wheel is locked and the rear wheel is not locked, the braking force of the rear wheel may be increased by a first predetermined increment, increasing the braking force of the rear wheel from the second braking force to the third braking force, thereby increasing the braking force of the rear wheel.

[0105] The slip rate threshold may be a slip rate that is greater than and close to a critical slip rate. The critical slip rate is the slip rate when the wheel is in a critical state of being about to lock. When the slip rate of the wheel reaches the slip rate threshold, it indicates that the wheel has locked.

[0106] In an embodiment of the present application, when one of the front and rear wheels of a vehicle is locked and the other is not locked, the braking force of the non-locked wheel is increased. In this way, when the non-locked wheel locks, the time difference between the locking time of the front wheel and the locking time of the rear wheel can be reduced, thereby improving braking efficiency, shortening braking distance, and improving vehicle safety.

[0107] Optionally, increasing the braking force of the third wheel to a third braking force includes:

[0108] determining a slip ratio deviation between a current slip ratio of a third wheel and a critical slip ratio;

[0109] When the slip ratio deviation is less than the preset deviation threshold, the braking force of the third wheel is increased to a third braking force.

[0110] In one embodiment, when it is determined that one of the front or rear wheels is locked, the current slip ratio of the third wheel (not locked) can be first detected and determined. In the above example, if the third wheel is a front wheel, the slip ratios of the left and right front wheels can be obtained, and the average of the slip ratios of the left and right front wheels can be calculated, with the average value used as the current slip ratio of the front wheel. The deviation between the current slip ratio and a critical slip ratio is then calculated to obtain a slip ratio deviation. The slip ratio deviation is then compared with a preset deviation threshold. If the slip ratio deviation is greater than or equal to the preset deviation threshold, it indicates that the current slip ratio of the third wheel differs significantly from the critical slip ratio. In this case, increasing the braking force on the third wheel may not shorten the locking time difference between the third and fourth wheels.

[0111] Conversely, when the slip ratio deviation is less than the preset deviation threshold, it indicates that the difference between the current slip ratio of the third wheel and the critical slip ratio is small. In this case, increasing the braking force on the third wheel is likely to shorten the locking time difference between the third and fourth wheels. Furthermore, when the slip ratio deviation is less than the preset deviation threshold, the braking force on the third wheel can be increased to the third braking force.

[0112] In this embodiment of the present application, when the fourth wheel is locked, if the slip ratio deviation between the third wheel's current slip ratio and the critical slip ratio is less than a preset deviation threshold, the braking force on the third wheel is increased to a third braking force. If the slip ratio deviation between the third wheel's current slip ratio and the critical slip ratio is greater than or equal to the preset deviation threshold, the braking force on the third wheel is not increased, thereby reducing unnecessary braking operations.

[0113] Optionally, before increasing the braking force of the third wheel to the third braking force, the method may further include:

[0114] determining a fourth braking force, the fourth braking force being greater than the braking force before the fourth wheel is locked, the fourth wheel being one of the front and rear wheels being locked;

[0115] A third braking force is determined according to the fourth braking force and the first braking force distribution curve.

[0116] In one embodiment, when increasing the braking force of the third wheel, the braking force before the fourth wheel locks can be first obtained. Based on the braking force before the fourth wheel locks, a second preset increase is added to the braking force before the fourth wheel locks to obtain a fourth braking force, such that the fourth braking force is greater than the braking force before the fourth wheel locks. Then, the third braking force is determined based on the fourth braking force and the first braking force distribution curve. For example, if the first wheel is a front wheel and the second wheel is a rear wheel, and it is determined that the front wheel is locked but the rear wheel is not locked, the braking force before the front wheel locks (i.e., the first braking force) can be obtained. The fourth braking force can then be summed with the first braking force and the second preset increase to obtain the fourth braking force. After obtaining the fourth braking force, the fourth braking force can be substituted into the formula corresponding to the first braking force distribution curve to calculate the third braking force. The left and right rear brake motors can then be controlled to increase the braking force of the rear wheels from the second braking force before the front wheel locks to the third braking force.

[0117] In the embodiment of the present application, a certain value is added to the braking force before the fourth wheel is locked to obtain the fourth braking force, and then the third braking force is determined based on the fourth braking force and the first braking force distribution curve. The braking force of the third wheel is increased to the third braking force, so that the braking force of the third wheel can be consistent with the first braking force distribution curve. In this way, when the non-locked wheels are locked, the time difference between the locking time of the front wheels and the locking time of the rear wheels can be reduced, thereby improving the braking efficiency, shortening the braking distance, and improving the safety of the vehicle.

[0118] Optionally, the method may further include increasing the braking force of the fourth wheel to a fourth braking force.

[0119] As described above, the third wheel is the one that is not locked between the front wheel and the rear wheel, and the fourth wheel is the one that is locked between the front wheel and the rear wheel.

[0120] In one embodiment, the braking force of the fourth wheel can be increased simultaneously with the braking force of the third wheel. As described above, after the third braking force is determined based on the fourth braking force and the first braking force distribution curve, the left rear brake motor and the right rear brake motor can be controlled to increase the braking force of the rear wheels from the second braking force to the third braking force. Simultaneously, the left front brake motor and the right front brake motor can be controlled to increase the braking force of the front wheels from the first braking force to the fourth braking force.

[0121] In the embodiment of the present application, while increasing the braking force of the non-locked third wheel, the braking force of the locked fourth wheel is increased, which can improve the consistency of the braking force of the third wheel and the fourth wheel. When the non-locked wheels are locked, the time difference between the locking time of the front wheels and the locking time of the rear wheels can be reduced, thereby improving the braking efficiency, shortening the braking distance, and improving the safety of the vehicle.

[0122] Optionally, before determining the third braking force according to the fourth braking force and the first braking force distribution curve, the method may further include:

[0123] determining at least one second braking force profile from the plurality of braking force profiles;

[0124] One of the at least one second braking force distribution curves is selected to replace the original first braking force distribution curve.

[0125] Among them, multiple braking force distribution curves correspond one-to-one to multiple load levels, the first braking force distribution curve is a braking force distribution curve corresponding to a target load level among the multiple braking force distribution curves, the target load level is a load level currently at which the vehicle is located, the second braking force distribution curve is a braking force distribution curve including a fifth braking force among the multiple braking force distribution curves, the fifth braking force is a braking force corresponding to a fourth braking force in the braking force distribution curve, and the fifth braking force is greater than the current braking force of the third wheel.

[0126] by Figure 3 For example, after the vehicle starts and the vehicle load level is level 3, the first braking force distribution curve selected is braking force distribution curve 33. When the brake pedal is detected as depressed, the first braking force of the front wheel (i.e., the first wheel) is determined based on the displacement of the brake pedal. Then, the second braking force of the rear wheel (i.e., the second wheel) is determined based on the first braking force and braking force distribution curve 33. The first braking force is the abscissa x1 of point C, and the second braking force is the ordinate of point C. Subsequently, the front wheel is braked according to the first braking force, and the rear wheel is braked according to the second braking force.

[0127] During braking, if locking of the front wheels is detected but the rear wheels are not, the braking force (i.e., the first braking force) applied to the fourth wheel (i.e., the front wheel) can be increased by a second predetermined increment. The sum of the first braking force and the second predetermined increment is the fourth braking force, which is the abscissa x2 at point D. At this point, braking force distribution curves 34 and 35 can be determined to include a fifth braking force. The fifth braking force is the ordinates of points D and E. Since the ordinates of points D and E are greater than the ordinate of point C (i.e., the current braking force of the third wheel), braking force distribution curves 34 and 35 can be determined to be the second braking force distribution curves.

[0128] Furthermore, braking force distribution curve 34 or braking force distribution curve 35 can be selected to replace the original first braking force distribution curve, that is, braking force distribution curve 34 or braking force distribution curve 35 can be used to replace braking force distribution curve 33. For example, after braking force distribution curve 35 is selected to replace braking force distribution curve 33, braking force distribution curve 35 becomes the new first braking force distribution curve. At this time, the fourth braking force can be substituted into the formula corresponding to braking force distribution curve 35 to calculate the corresponding third braking force, where the third braking force is the ordinate of point E.

[0129] In the embodiment of the present application, in the process of increasing the braking force of the third wheel, at least one second braking force distribution curve is determined from a plurality of braking force distribution curves, and the third braking force is determined based on the fourth braking force and one of the second braking force distribution curves. This not only increases the braking force of the third wheel, but also makes the braking forces of the third and fourth wheels consistent with the braking force distribution curves. Further, when the non-locked wheels lock, the time difference between the locking time of the front wheels and the locking time of the rear wheels can be reduced, thereby improving braking efficiency, shortening the braking distance, and improving vehicle safety.

[0130] Optionally, selecting one of the at least one second braking force distribution curves to replace the original first braking force distribution curve includes:

[0131] determining whether there are multiple second braking force distribution curves;

[0132] If so, one of the at least one second braking force distribution curves having a corresponding load level adjacent to the target load level is selected to replace the original first braking force distribution curve.

[0133] As in the above example, after braking force distribution curve 34 and braking force distribution curve 35 are determined to be the second braking force distribution curve, braking force distribution curve 34, which is adjacent to braking force distribution curve 33 (i.e., the original first braking force distribution curve), can be determined as the new first braking force distribution curve. Braking force distribution curve 33 corresponds to load level 3, and braking force distribution curve 34 corresponds to load level 4, adjacent to level 3. At this point, the fourth braking force can be substituted into the formula corresponding to braking force distribution curve 34 to calculate the corresponding third braking force, which is the ordinate of point D.

[0134] When there is only one second braking force distribution curve, the second braking force distribution curve can be directly used as the new first braking force distribution curve. When there is no second braking force distribution curve among the multiple second braking force distribution curves, the third braking force can be determined based on the fourth braking force and the original first braking force distribution curve.

[0135] In an embodiment of the present application, when there are multiple second braking force distribution curves, one of the multiple second braking force distribution curves having a corresponding load level adjacent to the current load level of the vehicle is selected to replace the original first braking force distribution curve. This can improve the matching degree between the braking force of the wheel and the current load level of the vehicle, and thus can reduce the time difference between the locking time of the front wheels and the locking time of the rear wheels, thereby improving braking efficiency, shortening the braking distance, and improving vehicle safety.

[0136] Optionally, the step of determining the current target load level of the vehicle from a plurality of load levels may include:

[0137] determining target parameters for the vehicle, the target parameters including a current suspension height of the vehicle and / or a current tire pressure of the vehicle;

[0138] Determine the target load level based on the target parameters.

[0139] For example, in determining the target load level, the vehicle's current suspension height (i.e., the current suspension height) can be obtained, and then the deviation between the current suspension height and the initial suspension height can be calculated to obtain a height change. The target load level can then be determined based on the height change. The method for determining the target load level based on the height change can be referenced to the aforementioned example and will not be further described in this embodiment.

[0140] For another example, in determining the target load level, the vehicle's current tire pressure (i.e., current tire pressure) can be obtained, and then the deviation between the current tire pressure and the initial tire pressure can be calculated to obtain the tire pressure change. The target load level is then determined based on the tire pressure change. The method for determining the target load level based on the tire pressure change can be referred to in the previous example and will not be further described in this embodiment.

[0141] For another example, in determining the target load level, the vehicle's current tire pressure and current suspension height can be obtained. The deviation between the current tire pressure and the initial tire pressure is then calculated to obtain the tire pressure change. The deviation between the current suspension height and the initial suspension height is also calculated to obtain the height change. The target load level is then determined based on the height change and tire pressure change. The method for determining the target load level based on tire pressure change and height change can be referenced to the previous example and will not be further described in this embodiment.

[0142] In the embodiment of the present application, the vehicle load level is determined based on the vehicle's suspension height and tire pressure, which can determine a relatively accurate load level. Furthermore, a first braking force distribution curve that has a high degree of matching with the vehicle's current load state can be determined based on the load level.

[0143] Optionally, after braking the first wheel and the second wheel according to the first braking force and the second braking force respectively, the method may further include:

[0144] When no locked wheel exists among the front wheels and the rear wheels, determining whether there is a target wheel among the front wheels and the rear wheels whose slip ratio reaches a critical slip ratio;

[0145] If so, the braking forces of the front and rear wheels other than the target wheel are increased to increase the slip ratio of the other wheels.

[0146] In one embodiment, after braking the front and rear wheels, if no wheels are locked, the slip ratio of each wheel can be acquired in real time and compared with the critical slip ratio. When the slip ratio of a wheel reaches the critical slip ratio, it can be determined that the wheel (i.e., the target wheel) is about to lock. At this point, the braking force on the other wheels can be increased to increase the slip ratio of the other wheels, thereby reducing the deviation between the slip ratio of the other wheels and the critical slip ratio. This increases the probability of simultaneous locking of the target wheel and the other wheels.

[0147] For example, after braking the front and rear wheels based on the first and second braking forces, the slip ratio of each wheel is obtained. When the slip ratio of the left front wheel (i.e., the target wheel) reaches the critical slip ratio, the braking forces of the right front wheel, left rear wheel, and right rear wheel can be increased to reduce the deviations between the slip ratios of the right front wheel, left rear wheel, and right rear wheel and the critical slip ratios. When increasing the braking forces of the right front wheel, left rear wheel, and right rear wheel, the braking force increment for each wheel can be controlled individually to prevent wheel locking.

[0148] In an embodiment of the present application, when no locked wheel appears among the front wheels and the rear wheels, if it is determined that there is a target wheel among the front wheels and the rear wheels whose slip rate reaches the critical slip rate, the braking force of the wheels other than the target wheel is increased to increase the slip rate of the other wheels, which can increase the probability of multiple wheels locking at the same time, thereby improving the safety of the vehicle during emergency braking.

[0149] See also Figure 4 , Figure 4 : is a flow chart of a braking method provided in an embodiment of the present application. The method may include the following steps:

[0150] Step 401: Obtain the current tire pressure and current suspension height of the vehicle.

[0151] Step 402: Determine the target load level according to the current tire pressure and the current suspension height.

[0152] Step 403: Determine a first braking force distribution curve according to the target load level.

[0153] For example, after the vehicle is started, the ECU may obtain the vehicle's current tire pressure and suspension height, then determine the vehicle's current target load level based on the current tire pressure and suspension height. It then determines a first braking force distribution curve corresponding to the target load level from among multiple braking force distribution curves. The specific processes of steps 401-403 can be found in the previous example and are not detailed here in this embodiment.

[0154] Step 404: Determine whether the brake pedal is depressed.

[0155] For example, after determining the first braking force distribution curve, the ECU monitors in real time whether the brake pedal is depressed, and executes step 405 when it is detected that the brake pedal is depressed.

[0156] Step 405: Determine a first braking force required by the first wheel.

[0157] Step 406: Determine the second braking force according to the first braking force and the first braking force distribution curve.

[0158] Step 407: Brake the first wheel and the second wheel according to the first braking force and the second braking force respectively.

[0159] For example, after determining the first braking force distribution curve, the ECU, upon detecting that the brake pedal is depressed, determines a first braking force for the first wheel based on the displacement of the brake pedal, and determines a second braking force for the second wheel based on the first braking force and the first braking force distribution curve. The ECU then brakes the first wheel based on the first braking force and the second wheel based on the second braking force. The specific processes of steps 405 through 407 can be found in the previous example and are not detailed here in this embodiment.

[0160] Step 408: Obtain the slip rate of each wheel.

[0161] Step 409: Determine whether the front wheels and rear wheels are locked synchronously based on the slip rate of each wheel.

[0162] For example, after executing step 407, the ECU may execute step 408 to obtain the slip ratios of the left front wheel, right front wheel, left rear wheel, and right rear wheel. After obtaining the slip ratios of each wheel, if it is determined that the slip ratios of each wheel are less than a preset slip ratio threshold, it is determined that the front and rear wheels are synchronously locked. At this time, the anti-lock braking system (ABS) in the vehicle is activated, and the ABS controls the braking process of the front and rear wheels, and the ECU terminates control.

[0163] On the contrary, if the front wheels and the rear wheels are not locked synchronously, step 410 is executed.

[0164] Step 410: Determine whether one of the front wheel and the rear wheel is locked and the other is not locked.

[0165] For example, when it is determined that the front wheels and the rear wheels are not locked synchronously, it is determined whether one of the front wheels and the rear wheels is locked and the other is not locked. If one of the front wheels and the rear wheels is not locked and the other is not locked, it is determined that neither the front wheels nor the rear wheels are locked, and the ECU continues to execute step 407. If one of the front wheels and the rear wheels is locked and the other is not locked, the ECU executes step 411.

[0166] Step 411: Determine a second braking force distribution curve from a plurality of braking force distribution curves.

[0167] Step 412: Use one of the second braking force distribution curves to replace the original first braking force distribution curve.

[0168] Step 413: Determine the fourth braking force and the third braking force.

[0169] Step 414: Control the braking force of the third wheel to increase to the third braking force, and control the braking force of the fourth wheel to increase to the fourth braking force.

[0170] Illustratively, when it is determined that one of the front and rear wheels is locked and the other is not locked, the ECU first determines at least one second braking force distribution curve from a plurality of braking force distribution curves, then selects one of the second braking force distribution curves to replace the original first braking force distribution curve, adds the current braking force of the fourth wheel to obtain a fourth braking force, determines a third braking force based on the fourth braking force and the replaced first braking force distribution curve, and then controls the braking force of the third wheel to increase to the third braking force, and controls the braking force of the fourth wheel to increase to the fourth braking force.

[0171] See also Figure 5 , Figure 5 This is a schematic diagram of the structure of a braking device provided in an embodiment of the present application. Figure 5 As shown, the braking device 500 is provided in the ECU and includes:

[0172] A first determining module 501 is configured to determine a first braking force required by a first wheel when the vehicle needs to brake, where the first wheel is one of a front wheel and a rear wheel of the vehicle;

[0173] a second determining module 502, configured to determine a second braking force required for a second wheel based on a first braking force distribution curve and the first braking force, where the second wheel is the other of the front wheel and the rear wheel other than the first wheel, and the first braking force distribution curve is a relationship curve between the braking force of the front wheel and the braking force of the rear wheel when the front wheel and the rear wheel are synchronously locked;

[0174] The braking module 503 is configured to brake the first wheel and the second wheel according to the first braking force and the second braking force respectively.

[0175] Optionally, the braking device 500 further includes: an increasing module for increasing the braking force of a third wheel to a third braking force when one of the front wheel and the rear wheel is locked, and the third wheel is the one of the front wheel and the rear wheel that is not locked.

[0176] Optionally, the adding module is further used to determine a fourth braking force, which is greater than the braking force before the fourth wheel is locked, and the fourth wheel is one of the front wheel and the rear wheel that is locked; and determine the third braking force based on the fourth braking force and the first braking force distribution curve.

[0177] Optionally, the adding module is further used to determine at least one second braking force distribution curve from a plurality of braking force distribution curves, the plurality of braking force distribution curves corresponding one-to-one to a plurality of load levels, the first braking force distribution curve being a braking force distribution curve corresponding to a target load level among the plurality of braking force distribution curves, the target load level being one of the load levels currently at which the vehicle is located, the second braking force distribution curve being a braking force distribution curve including a fifth braking force among the plurality of braking force distribution curves, the fifth braking force being a braking force corresponding to the fourth braking force in the braking force distribution curve, the fifth braking force being greater than the current braking force of the third wheel; and one of the at least one second braking force distribution curves is selected to replace the original first braking force distribution curve.

[0178] Optionally, the adding module is specifically used to determine whether there are multiple second braking force distribution curves; if so, select one from the at least one second braking force distribution curve whose corresponding load level is adjacent to the target load level to replace the original first braking force distribution curve.

[0179] Optionally, the increasing module is specifically configured to determine a slip rate deviation between a current slip rate of the third wheel and a critical slip rate; and when the slip rate deviation is less than a preset deviation threshold, increase the braking force of the third wheel to the third braking force.

[0180] Optionally, the braking device 500 further includes: an increasing module for determining whether there is a target wheel among the front wheels and the rear wheels whose slip rate reaches a critical slip rate when no locked wheel occurs among the front wheels and the rear wheels; if so, increasing the braking force of the other wheels among the front wheels and the rear wheels except the target wheel to increase the slip rate of the other wheels.

[0181] Optionally, the first braking force distribution curve is a nonlinear polynomial curve, the independent variable of the nonlinear polynomial curve is the first braking force, and the dependent variable is the second braking force.

[0182] Optionally, each coefficient in the nonlinear polynomial curve corresponds to a current load level of the vehicle, and when the vehicle is at different load levels, each coefficient in the nonlinear polynomial curve is different.

[0183] See also Figure 6 , Figure 6 This is a schematic diagram of the structure of a device provided in an embodiment of the present application. Figure 6 As shown, the device 600 includes: a memory 601 and a processor 602, wherein the memory 601 stores an executable program code 6011, and the processor 602 is used to call and execute the executable program code 6011 to perform a braking method.

[0184] In addition, an embodiment of the present application also protects a braking device, which may include a memory and a processor, wherein the memory stores executable program code, and the processor is used to call and execute the executable program code to perform a braking method provided by an embodiment of the present application.

[0185] In this embodiment, the device can be divided into functional modules based on the above-described method examples. For example, each functional module can be mapped to a specific functional module, or two or more functions can be integrated into a single processing module. The integrated module can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and represents only a logical functional division. In actual implementation, other division methods may be used.

[0186] In the case of dividing each functional module into corresponding functional modules, the device may further include a determination module, a replacement module, a control module, etc. It should be noted that all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module and will not be repeated here.

[0187] It should be understood that the device provided in this embodiment is used to execute one of the above-mentioned braking methods, and thus can achieve the same effect as the above-mentioned implementation method.

[0188] In the case of an integrated unit, the device may include a determination module and a control module. When the device is applied to a device, the processing module may be used to control and manage the device's actions. The storage module may be used to support the device in executing relevant program codes, etc.

[0189] The processing module may be a processor or a vehicle body configuration module, which may implement or execute the various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure herein. The processor may also be a combination of devices that implement computing functions, such as a combination of one or more microprocessors, a combination of a digital signal processing system (DSP) and a microprocessor, and the storage module may be a memory.

[0190] This embodiment further provides a readable storage medium, in which program code is stored. When the program code is run on an electronic device, the electronic device executes the above-mentioned related method steps to implement a braking method provided in the above embodiment.

[0191] This embodiment further provides a program product. When the program product is run on an electronic device, the electronic device is caused to execute the above-mentioned related steps to implement a braking method provided in the above embodiment.

[0192] Among them, the device, readable storage medium, program product or chip provided in this embodiment is used to execute the corresponding method provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding method provided above, and will not be repeated here.

[0193] Through the description of the above implementation methods, technical personnel in the relevant field can understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be distributed and completed by different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0194] In the embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of modules or units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0195] The above content is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A braking method, characterized in that: The method comprises: determining a first braking force required by a first wheel when the vehicle needs to brake, the first wheel being one of a front wheel and a rear wheel of the vehicle; determining a second braking force required for a second wheel based on a first braking force distribution curve and the first braking force, where the second wheel is the other of the front wheel and the rear wheel other than the first wheel, and the first braking force distribution curve is a relationship curve between the braking force of the front wheel and the braking force of the rear wheel when the front wheel and the rear wheel are synchronously locked; The first wheel and the second wheel are braked according to the first braking force and the second braking force, respectively.

2. The method according to claim 1, wherein After braking the first wheel and the second wheel according to the first braking force and the second braking force respectively, the method further includes: When one of the front wheel and the rear wheel is locked, the braking force of a third wheel is increased to a third braking force. The third wheel is the one of the front wheel and the rear wheel that is not locked.

3. The method according to claim 2, wherein Before increasing the braking force of the third wheel to the third braking force, the method further includes: determining a fourth braking force, the fourth braking force being greater than the braking force before a fourth wheel is locked, the fourth wheel being one of the front wheel and the rear wheel that is locked; The third braking force is determined according to the fourth braking force and the first braking force distribution curve.

4. The method according to claim 3, wherein Before determining the third braking force according to the fourth braking force and the first braking force distribution curve, the method further includes: determining at least one second braking force distribution curve from a plurality of braking force distribution curves, the plurality of braking force distribution curves corresponding one-to-one to a plurality of load levels, the first braking force distribution curve being a braking force distribution curve corresponding to a target load level among the plurality of braking force distribution curves, the target load level being a load level currently at which the vehicle is located, and the second braking force distribution curve being a braking force distribution curve among the plurality of braking force distribution curves that includes a fifth braking force, the fifth braking force being a braking force corresponding to the fourth braking force among the braking force distribution curves, the fifth braking force being greater than the current braking force of the third wheel; One of the at least one second braking force distribution curve is selected to replace the original first braking force distribution curve.

5. The method according to claim 4, wherein The selecting one of the at least one second braking force distribution curve to replace the original first braking force distribution curve comprises: determining whether there is a plurality of the second braking force distribution curves; If so, one of the at least one second braking force distribution curves having a corresponding load level adjacent to the target load level is selected to replace the original first braking force distribution curve.

6. The method according to claim 3, wherein Increasing the braking force of the third wheel to a third braking force includes: determining a slip ratio deviation between a current slip ratio of the third wheel and a critical slip ratio; When the slip ratio deviation is smaller than a preset deviation threshold, the braking force of the third wheel is increased to the third braking force.

7. The method according to claim 1, wherein After braking the first wheel and the second wheel according to the first braking force and the second braking force respectively, the method further includes: When no locked wheel occurs among the front wheels and the rear wheels, determining whether there is a target wheel among the front wheels and the rear wheels whose slip rate reaches a critical slip rate; If so, the braking forces of the other wheels among the front wheels and the rear wheels except the target wheel are increased to increase the slip ratio of the other wheels.

8. The method according to any one of claims 1 to 7, wherein The first braking force distribution curve is a nonlinear polynomial curve, the independent variable of the nonlinear polynomial curve is the first braking force, and the dependent variable is the second braking force.

9. The method according to claim 8, wherein Each coefficient in the nonlinear polynomial curve corresponds to the current load level of the vehicle. When the vehicle is at different load levels, the coefficients in the nonlinear polynomial curve are different.

10. A braking device, characterized in that: include: a first determining module, configured to determine a first braking force required by a first wheel when the vehicle needs to brake, the first wheel being one of a front wheel and a rear wheel of the vehicle; a second determining module, configured to determine a second braking force required for a second wheel based on a first braking force distribution curve and the first braking force, where the second wheel is the other of the front wheel and the rear wheel other than the first wheel, and the first braking force distribution curve is a relationship curve between the braking force of the front wheel and the braking force of the rear wheel when the front wheel and the rear wheel are synchronously locked; A braking module is configured to brake the first wheel and the second wheel according to the first braking force and the second braking force respectively.

11. A readable storage medium, characterized in that: The readable storage medium stores a program code, and when the program code is executed on an electronic device, the electronic device executes the method according to any one of claims 1 to 8.

12. A vehicle, characterized in that: The vehicle comprises: a memory for storing executable program code; A processor is configured to call and run the executable program code from the memory, so that the vehicle executes the method according to any one of claims 1 to 8.

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