Method for determining brake pressure of trailer and method for controlling brake of trailer

Abstract

The embodiment of the invention provides a trailer brake pressure determination method and a trailer brake control method. The method comprises the following steps: after a tractor and a trailer are connected, acquiring multiple groups of sample data of the trailer; wherein each group of sample data comprises the actual braking pressure and the actual linear interpolation coefficient of the trailer; the actual linear interpolation coefficient represents an interpolation ratio between a preset upper boundary equation and a preset lower boundary equation; establishing a first mapping relation based on the actual brake pressure and the actual linear interpolation coefficient in each group of sample data; the first mapping relation represents the corresponding relation between the linear interpolation coefficient and the brake pressure; substituting the first mapping relation into a preset linear interpolation equation to obtain a second mapping relation; the second mapping relation is used for determining the target braking pressure of the trailer based on the target deceleration of the tractor. The method is used for achieving the effect of improving the accuracy of the trailer brake pressure.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and in particular to a method for determining trailer braking pressure and a method for controlling trailer braking. Background Technology

[0002] In long-haul freight or short-haul logistics, the braking performance of a trailer, as a vehicle without a power unit, directly depends on the control capability of the tractor unit. Therefore, accurately determining the braking pressure of the trailer by the tractor unit is a core prerequisite for achieving coordinated braking between the tractor and trailer, and is of crucial significance for ensuring the braking safety, compliance, and driving stability of the entire vehicle.

[0003] In related technologies, the method for determining the braking pressure of the trailer by the tractor is mostly based on a preset global linear model. That is, by using fixed linear interpolation equations, the braking intensity is adjusted with fixed adjustment parameters within the upper and lower boundaries of the braking pressure-deceleration range defined by regulations, thereby establishing a correspondence between braking pressure and tractor deceleration. However, the linear model cannot match the actual nonlinear characteristics of the braking system, resulting in a disconnect between braking force distribution and actual needs, and insufficient braking accuracy. Summary of the Invention

[0004] The method for determining trailer braking pressure and the method for controlling trailer braking provided in this application are intended to improve the accuracy of trailer braking pressure.

[0005] In a first aspect, embodiments of this application provide a method for determining trailer braking pressure, comprising:

[0006] After the tractor and trailer are connected, multiple sets of sample data of the trailer are acquired; each set of sample data includes the actual braking pressure of the trailer and the actual linear interpolation coefficient; the actual linear interpolation coefficient represents the interpolation ratio between the preset upper boundary equation and the lower boundary equation; the boundary equation represents the boundary of the corresponding relationship between the braking pressure of the trailer and the deceleration of the tractor.

[0007] Based on the actual braking pressure and the actual linear interpolation coefficient in each set of sample data, a first mapping relationship is established; wherein, the first mapping relationship characterizes the correspondence between the linear interpolation coefficient and the braking pressure;

[0008] Substituting the first mapping relationship into the preset linear interpolation equation, a second mapping relationship is obtained; wherein, the linear interpolation equation characterizes the correspondence between braking pressure and deceleration after using linear interpolation coefficients; the second mapping relationship is used to determine the target braking pressure of the trailer based on the target deceleration of the tractor.

[0009] In one possible implementation, establishing the first mapping relationship based on the actual braking pressure and the actual linear interpolation coefficient in each set of sample data includes:

[0010] For each set of sample data, the predicted linear interpolation coefficients are obtained based on the actual braking pressure of that set of sample data and the preset initial mapping relationship.

[0011] Based on the predicted linear interpolation coefficients and the actual linear interpolation coefficients of the sample data, the optimal parameters of the initial mapping relationship are determined, and the first mapping relationship is obtained.

[0012] In one possible implementation, obtaining the actual linear interpolation coefficients in each set of sample data includes:

[0013] Obtain the actual deceleration of the tractor corresponding to the actual braking pressure in this set of sample data;

[0014] Based on the actual braking pressure, the upper boundary equation, and the lower boundary equation in this set of sample data, the maximum deceleration and the minimum deceleration corresponding to the actual braking pressure are determined respectively.

[0015] The actual linear interpolation coefficients in the sample data are determined based on the maximum deceleration, the minimum deceleration, and the actual deceleration.

[0016] In one possible implementation, the method further includes:

[0017] Obtain the target deceleration of the tractor;

[0018] Based on the second mapping relationship and the target deceleration, the target braking pressure of the trailer is determined.

[0019] Secondly, embodiments of this application provide a trailer braking control method, the method being applied to a controller of a tractor unit, the tractor unit being connected to a trailer; including:

[0020] Obtain the target deceleration of the tractor;

[0021] Based on a preset second mapping relationship and the target deceleration, the target braking pressure of the trailer is determined; wherein, the second mapping relationship is the second mapping relationship as described in any one of the first aspects;

[0022] The trailer brakes are controlled based on the target braking pressure.

[0023] Thirdly, embodiments of this application provide a device for determining trailer braking pressure, comprising:

[0024] The acquisition module is used to acquire multiple sets of sample data of the trailer after the tractor and trailer are connected; wherein each set of sample data includes the actual braking pressure of the trailer and the actual linear interpolation coefficient; the actual linear interpolation coefficient represents the interpolation ratio between the preset upper boundary equation and the lower boundary equation; the boundary equation represents the boundary of the corresponding relationship between the braking pressure of the trailer and the deceleration of the tractor.

[0025] A module is established to establish a first mapping relationship based on the actual braking pressure and the actual linear interpolation coefficient in each set of sample data; wherein the first mapping relationship characterizes the correspondence between the linear interpolation coefficient and the braking pressure;

[0026] The processing module is used to substitute the first mapping relationship into a preset linear interpolation equation to obtain a second mapping relationship; wherein the linear interpolation equation represents the correspondence between braking pressure and deceleration after using linear interpolation coefficients; the second mapping relationship is used to determine the target braking pressure of the trailer based on the target deceleration of the tractor.

[0027] Fourthly, embodiments of this application provide a trailer braking control device, comprising:

[0028] The acquisition module is used to acquire the target deceleration of the tractor.

[0029] The determining module is configured to determine the target braking pressure of the trailer based on a preset second mapping relationship and the target deceleration; wherein the second mapping relationship is the second mapping relationship as described in any one of the first aspects;

[0030] The control module is used to control the trailer brake based on the target braking pressure.

[0031] In one possible implementation, determining the target braking pressure of the trailer based on a preset second mapping relationship and the target deceleration includes:

[0032] Substituting the target deceleration into the second mapping relationship, the target braking pressure of the trailer is obtained by solving.

[0033] Fifthly, embodiments of this application provide an electronic device, including: a memory and a processor;

[0034] The memory stores computer-executed instructions;

[0035] The processor executes computer execution instructions stored in the memory, causing the processor to perform various possible implementations of the first and / or second aspects described above.

[0036] In a sixth aspect, embodiments of this application provide a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement various possible implementations of the first and / or second aspects described above.

[0037] In a seventh aspect, embodiments of this application provide a computer program product, including a computer program that, when executed by a processor, implements various possible implementations of the first and / or second aspects described above.

[0038] The method for determining trailer braking pressure and the method for controlling trailer braking provided in this application, after the tractor and trailer are connected, firstly acquire multiple sets of sample data containing the actual braking pressure of the trailer and the actual linear interpolation coefficients. Based on the sample data, a first mapping relationship characterizing the correspondence between the linear interpolation coefficients and the braking pressure is established. Then, this first mapping relationship is substituted into a preset linear interpolation equation to obtain a second mapping relationship that can determine the target braking pressure of the trailer based on the target deceleration of the tractor. This approach, on the one hand, breaks the limitations of the global linear model in the prior art. By using the first mapping relationship to drive the linear interpolation equation to form a nonlinear second mapping relationship, it can accurately fit the nonlinear characteristics of different pressure ranges of the braking system, improving the accuracy of trailer braking pressure determination. On the other hand, by establishing the mapping relationship driven by sample data, it can adapt to the differences in braking characteristics of trailers of different specifications. When the tractor is replaced with a trailer, only the sample data needs to be re-collected to establish a new first mapping relationship, improving the scenario adaptability of the method and the braking accuracy of the trailer. Attached Figure Description

[0039] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0040] Figure 1 A schematic diagram illustrating the relationship between braking pressure and deceleration provided in this application;

[0041] Figure 2 A schematic diagram illustrating the correspondence between linear interpolation coefficients and braking pressure provided in this application;

[0042] Figure 3 Flowchart of the method for determining trailer braking pressure provided in this application Figure 1 ;

[0043] Figure 4 Flowchart of the method for determining trailer braking pressure provided in this application Figure 2 ;

[0044] Figure 5A schematic diagram of an iterative curve of a loss function provided in this application;

[0045] Figure 6 A schematic diagram illustrating the correspondence between linear interpolation coefficients and braking pressure provided in this application;

[0046] Figure 7 Flowchart of the trailer braking control method provided in this application Figure 1 ;

[0047] Figure 8 A schematic diagram of the device for determining trailer braking pressure provided in this application;

[0048] Figure 9 A schematic diagram of the control device for trailer braking provided in this application;

[0049] Figure 10 A schematic diagram of the structure of the electronic device provided in this application.

[0050] The accompanying drawings have illustrated specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to specific embodiments. Detailed Implementation

[0051] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0052] First, the terms used in the embodiments of this application will be explained:

[0053] Tractor: A tractor unit is a vehicle equipped with power output, driving control, and braking systems. It provides traction, controls the direction of travel, and issues braking commands to the entire tractor-trailer combination. In braking scenarios, the tractor unit is equipped with components such as a brake control unit and deceleration sensors. It can collect its own deceleration data, generate braking control commands, and transmit control signals to the trailer to achieve braking of both the tractor unit and the trailer.

[0054] A trailer is a vehicle without an independent power unit that needs to be connected to a tractor unit via a coupling device to carry goods. It is understood that the trailer's braking system relies on the tractor unit's control commands to achieve braking action and cannot generate braking signals actively on its own. It should be noted that the connection method between the trailer and the tractor unit is not limited in this application embodiment.

[0055] Figure 1 This is a schematic diagram illustrating the relationship between braking pressure and deceleration provided in this application. Figure 1 As shown in (a), the horizontal axis represents the braking pressure of the trailer, the vertical axis represents the braking intensity of the tractor, and the curve represents the compliant range of the legally stipulated relationship between the trailer's braking pressure and the tractor's deceleration (shown in the shaded area in the figure). In practical applications, the relationship between the trailer's braking pressure and the tractor's deceleration should be within this compliant range and should not exceed the upper or lower boundaries.

[0056] To simplify the control logic and calculations, Figure 1 In (a), the upper and lower boundaries are abstracted as linear relationships, such as... Figure 1 As shown in (b), the horizontal axis represents braking pressure, and the vertical axis represents deceleration. Curve 1 corresponds to the aforementioned upper boundary, and curve 2 corresponds to the aforementioned lower boundary. The two curves together define the compliance range of braking characteristics. By using linear interpolation coefficients, practical application curves corresponding to braking pressure and deceleration with different linear interpolation coefficients are set between the upper and lower boundaries. Thus, in actual control, after determining the deceleration of the tractor, the braking pressure of the trailer can be found based on the set practical application curves.

[0057] To further improve the precision of braking control and vehicle compatibility, such as Figure 1 As shown in (c), based on Figure 1 (b) The upper and lower boundaries can further narrow down the control boundary between braking pressure and deceleration to a more precise level. In other words, within the legally permissible compliance range, and considering the specific vehicle model's braking system characteristics, additional, stricter upper boundaries (curve 3) and lower boundaries (curve 4) are set. This narrowing reduces the risk of approaching the compliance boundary and makes the braking control more suitable for the actual vehicle model's characteristics. Furthermore, between the further narrowed upper and lower boundaries, different linear interpolation coefficients can be set to correspond to actual application curves between braking pressure and deceleration. Thus, in actual control, after determining the deceleration of the tractor, the braking pressure of the trailer can be found based on the set actual application curves.

[0058] However, in the above methods, refer to Figure 2 As shown, Figure 2 This application provides a schematic diagram illustrating the correspondence between linear interpolation coefficients and braking pressure. Figure 2The diagram illustrates the relationship between the linear interpolation coefficient and braking pressure when the linear interpolation coefficient is 50%. It shows that once the linear interpolation coefficient is set to a certain value, the corresponding relationship between braking pressure and deceleration determined based on that value is applied to all braking pressure values. In other words, the above method establishes a global linear model, that is, using fixed linear interpolation coefficients to adjust the braking intensity, thereby establishing a linear equation between braking pressure and tractor deceleration with fixed slope and intercept. However, in actual braking systems, the slope of deceleration changing with braking pressure varies nonlinearly across different braking pressure ranges. The global linear model cannot fit this, leading to a disconnect between braking force distribution and actual braking demand, resulting in insufficient braking control accuracy.

[0059] Based on this, the inventors of this application realized that the core of the problem lies in the lack of correlation between the linear interpolation coefficients and the braking pressure, which makes it impossible for the linear interpolation equation to be dynamically adjusted according to different braking pressure ranges to match the actual deceleration requirements. Therefore, they considered constructing a direct correlation between the linear interpolation coefficients and the trailer braking pressure, and substituting the correspondence between the linear interpolation coefficients and the trailer braking pressure as a driving term into the linear interpolation equation. This breaks the limitation of global linearity, allowing the correspondence between braking pressure and the deceleration of the tractor to exhibit nonlinear characteristics that fit the actual braking requirements as the pressure changes, thereby achieving accurate determination of the trailer braking pressure and improving the braking control accuracy of the trailer.

[0060] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0061] First, the method for establishing the second mapping relationship between the deceleration of the tractor and the braking pressure of the trailer is explained. The execution entity in this embodiment can be an electronic device with processing capabilities, such as a computer, server, or a controller or domain controller in the tractor; this application embodiment does not limit this. This embodiment can be performed during the testing phase before the tractor and trailer leave the factory; it can also be performed during the testing phase in actual application when the tractor or trailer changes. Changes to the tractor or trailer include, but are not limited to, tractor replacing trailer, trailer replacing tractor, changes in trailer load, etc.; alternatively, the second mapping relationship can be updated periodically after the tractor and trailer are connected. This application embodiment does not limit the specific application scenario of this method.

[0062] Taking electronic devices as the executing entity as an example, Figure 3 Flowchart of the method for determining trailer braking pressure provided in this application Figure 1 ,like Figure 3 As shown, the method includes:

[0063] S101. After the tractor and trailer are connected, acquire multiple sets of sample data.

[0064] For example, each set of sample data includes the actual braking pressure of the trailer and the actual linear interpolation coefficient; wherein, the actual braking pressure of the trailer refers to the actual pressure value generated when the trailer braking system performs braking action; the actual linear interpolation coefficient is a proportional parameter characterizing the interpolation between the preset upper boundary equation and the lower boundary equation.

[0065] It is understandable that the magnitude of the linear interpolation coefficient directly corresponds to the position of the braking pressure-deceleration curve after interpolation. For example, a linear interpolation coefficient of 0 corresponds to the lower boundary equation, and a linear interpolation coefficient of 100 corresponds to the upper boundary equation.

[0066] Boundary equations are boundary-limiting equations characterizing the relationship between trailer braking pressure and tractor deceleration. They include upper and lower boundary equations, which together define the compliant range of braking characteristics. In other words, the upper boundary equation represents the maximum permissible tractor deceleration under a certain braking pressure, and the lower boundary equation represents the minimum permissible tractor deceleration under a certain braking pressure. It should be noted that the embodiments in this application do not limit the upper and lower boundary equations; for example, they can be... Figure 1 Curve 1 and curve 2 in the text can also be Figure 1 Curves 3 and 4 in the diagram can be set according to actual needs.

[0067] It should be noted that the number of sample data collected in this embodiment of the application is not limited.

[0068] In one example, after the tractor and trailer are connected, the electronic device can receive multiple sets of sample data sent by other electronic devices, or multiple sets of sample data imported from a storage device, such as a USB flash drive. Alternatively, the electronic device can act as a host computer, connected to a bench simulation testing system, to collect the actual braking pressure of the trailer in real time based on pressure sensors and the actual deceleration of the tractor based on deceleration sensors. Combining this with preset upper and lower boundary equations, the system calculates the actual linear interpolation coefficients corresponding to each set of actual braking pressures, and finally integrates them to form multiple sets of sample data.

[0069] S102. Based on the actual braking pressure and actual linear interpolation coefficients in each set of sample data, establish the first mapping relationship.

[0070] For example, the first mapping relationship refers to the correspondence between the linear interpolation coefficients and the trailer braking pressure, in order to establish a precise relationship between the two parameters. Given any trailer braking pressure, the corresponding linear interpolation coefficients can be directly determined. It should be noted that the embodiments of this application do not limit the form of the first mapping relationship; for example, it can be a linear relationship or a non-linear relationship.

[0071] In one example, this first mapping relationship can be represented as a linear relationship. In this case, the actual braking pressure from multiple sets of sample data is used as the independent variable, and the actual linear interpolation coefficients are used as the dependent variable. A linear regression algorithm is used for fitting calculation. By minimizing the error between the predicted value and the actual linear interpolation coefficients using the least squares method, the coefficients in the linear equation, such as the slope and intercept, are determined, thus obtaining the first mapping relationship.

[0072] In other examples, this first mapping relationship can also be represented as a non-linear relationship, for example, as a high-order (2nd or 3rd order) polynomial. When the first mapping relationship is non-linear, a corresponding high-order fitting algorithm can be used to obtain the polynomial that best fits the sample data. This will not be elaborated further here.

[0073] S103. Substitute the first mapping relationship into the preset linear interpolation equation to obtain the second mapping relationship.

[0074] For example, the linear interpolation equation is an interpolation calculation equation that characterizes the relationship between the trailer braking pressure and the tractor deceleration after using linear interpolation coefficients. The equation parameters can be adjusted by the linear interpolation coefficients to obtain the braking characteristic curve between the upper and lower boundaries.

[0075] For example, the upper boundary equation can be expressed as: The lower boundary equation can be expressed as: ;in, This represents the slope in the equation of the upper boundary. This represents the intercept in the upper boundary equation. This represents the slope in the lower boundary equation. This represents the intercept in the lower boundary equation; Indicates the upper boundary of deceleration; Indicates the lower boundary of deceleration; This indicates braking pressure.

[0076] In this implementation, the deceleration after using linear interpolation coefficients can be expressed as: ,in, Represents the linear interpolation coefficients. This represents the deceleration after applying linear interpolation coefficients. Furthermore, the linear interpolation equation is assumed to be a linear relationship; substituting... and The intercept and slope of the linear interpolation equation can then be obtained, specifically expressed as: It should be noted that the value of PMK in this linear interpolation equation is related to the defined range of the linear interpolation coefficients. If the range of the linear interpolation coefficients is 0-1, the aforementioned representation can be used; if the range of the linear interpolation coefficients is 0-100, it can be expressed as: .

[0077] The second mapping relationship is the final model obtained by substituting the first mapping relationship into the linear interpolation equation, which directly represents the correspondence between the deceleration of the tractor and the braking pressure of the trailer. It can determine the corresponding target braking pressure of the trailer based on the target deceleration of the tractor.

[0078] In one example, the first mapping relationship obtained above can be substituted into a preset linear interpolation equation, replacing the linear interpolation coefficients in the equation, to obtain a nonlinear equation containing only two variables: the tractor deceleration and the trailer braking pressure, i.e., the second mapping relationship. In practical applications, the target deceleration of the tractor is substituted into this nonlinear equation, and the corresponding target braking pressure of the trailer can be directly obtained by solving the equation.

[0079] The method for determining trailer braking pressure provided in this application involves acquiring multiple sets of sample data, including the actual braking pressure and actual linear interpolation coefficients of the trailer, after the tractor and trailer are connected. Based on the sample data, a first mapping relationship characterizing the correspondence between the linear interpolation coefficients and the braking pressure is established. This first mapping relationship is then substituted into a preset linear interpolation equation to obtain a second mapping relationship that allows the determination of the trailer's target braking pressure based on the tractor's target deceleration. This approach overcomes the limitations of the global linear model in existing technologies by using the first mapping relationship to drive the linear interpolation equation to form a nonlinear second mapping relationship. This accurately matches the nonlinear characteristics of different pressure ranges in the braking system, improving the accuracy of trailer braking pressure determination. Furthermore, by establishing the mapping relationship through sample data, it can adapt to the differences in braking characteristics of trailers of different specifications. When the tractor or trailer changes, only re-collecting sample data is needed to establish a new first mapping relationship, improving the method's scenario adaptability and the braking accuracy of the trailer.

[0080] Figure 4 Flowchart of the method for determining trailer braking pressure provided in this application Figure 2 ,like Figure 4 As shown, in this embodiment... Figure 3 Based on the embodiments, the method for determining trailer braking pressure is described in detail, which includes:

[0081] S201. After the tractor and trailer are connected, obtain multiple sets of sample data of the trailer.

[0082] For example, each set of sample data includes the actual braking pressure of the trailer and the actual deceleration of the tractor unit corresponding to that actual braking pressure. The actual deceleration of the tractor unit refers to the deceleration acceleration generated by the tractor unit along the direction of travel under the corresponding trailer braking pressure.

[0083] It should be noted that this step is similar to the aforementioned step S101, and will not be repeated here.

[0084] S202. Based on the actual braking pressure, upper boundary equation, and lower boundary equation in the sample data, determine the maximum deceleration and minimum deceleration corresponding to the actual braking pressure, respectively.

[0085] For example, the maximum deceleration refers to the deceleration calculated by substituting the actual braking pressure in the sample data into the upper boundary equation; the minimum deceleration refers to the deceleration calculated by substituting the same actual braking pressure into the lower boundary equation.

[0086] In one example, referring to the upper and lower boundary equations in the aforementioned embodiments, by substituting the actual braking pressure in the sample data, the maximum deceleration and minimum deceleration corresponding to the actual braking pressure can be obtained respectively.

[0087] S203. Determine the actual linear interpolation coefficients in the sample data based on the maximum deceleration, minimum deceleration, and actual deceleration.

[0088] For example, as mentioned above, the actual linear interpolation coefficient can characterize the interpolation ratio of the actual deceleration of the tractor between the maximum deceleration and the minimum deceleration, and quantify the position of the actual deceleration relative to the boundary interval. In other words, when the actual linear interpolation coefficient is 0, the actual deceleration is equal to the minimum deceleration; when the actual linear interpolation coefficient is 100, the actual deceleration is equal to the maximum deceleration; when the actual linear interpolation coefficient is between 0 and 100, the actual deceleration is between the two boundary decelerations.

[0089] Furthermore, the actual linear interpolation coefficient can be calculated based on the formula: Actual linear interpolation coefficient = (Actual deceleration - Minimum deceleration) / (Maximum deceleration - Minimum deceleration) × 100. It is understood that the calculated actual linear interpolation coefficient should be within the range of 0 to 100. If it exceeds this range, it indicates that the actual deceleration of the corresponding sample data exceeds the compliant range, and the data set should be discarded or re-collected.

[0090] It should be noted that the above example is based on the linear interpolation coefficients being in the range of 0 to 100. The principle is similar when the linear interpolation coefficients are in the range of 0 to 1, and no limitation is made here.

[0091] S204. For each set of sample data, based on the actual braking pressure of the set of sample data and the preset initial mapping relationship, obtain the predicted linear interpolation coefficients.

[0092] For example, the initial mapping relationship is an initial mathematical model used to initially correlate the actual braking pressure of the trailer with the linear interpolation coefficient. This initial mapping relationship can be linear or nonlinear. The predicted linear interpolation coefficient is the predicted value of the linear interpolation coefficient calculated by substituting the actual braking pressure of a set of sample data into the initial mapping relationship. It can be understood that, taking the initial mapping relationship as a linear relationship as an example, the initial mapping relationship has initial parameters, such as the initial intercept and the initial slope.

[0093] S205. Based on the predicted linear interpolation coefficients and the actual linear interpolation coefficients of the sample data, determine the optimal parameters of the initial mapping relationship to obtain the first mapping relationship.

[0094] For example, the optimal parameters refer to the parameters in the initial mapping relationship that minimize the overall deviation between the predicted linear interpolation coefficients and the actual linear interpolation coefficients, such as the intercept and slope.

[0095] In one example, the electronic device can use the least squares method to determine the optimal parameters of the initial mapping relationship by calculating the minimum of the sum of squared errors between the predicted linear interpolation coefficients and the actual linear interpolation coefficients, thereby obtaining the first mapping relationship.

[0096] Specifically, taking an initial linear mapping relationship as an example, this initial mapping relationship can be expressed as: ,in, and The initial slope and initial intercept are preset. Represents the linear interpolation coefficients. This indicates braking pressure.

[0097] The loss function is set as follows: ,in, Represents the actual linear interpolation coefficients of the i-th group; This represents the actual braking pressure of the i-th group; represents the predicted linear interpolation coefficient corresponding to the actual braking pressure of the i-th group; m represents the number of sample data groups; This represents the loss function value, used to measure the current... The corresponding initial mapping relationship represents the overall bias when fitting sample data. The optimization objective is to minimize... .

[0098] The parameter update rules for the initial mapping relationship can be obtained using the gradient descent algorithm: and ;in, This represents the preset learning rate; after substituting it into the loss function and transforming it, we can obtain: and .

[0099] Electronic devices can first extract the actual braking pressure from each set of sample data. Substituting these values ​​into the aforementioned initial mapping relationship, we obtain the predicted linear interpolation coefficients. Therefore, the loss function value can be calculated based on each predicted linear interpolation coefficient and the corresponding actual linear interpolation coefficient. After substituting the loss function values ​​into the aforementioned parameter update formula, the parameters of the initial mapping relationship are updated. and The updated initial mapping relationship is obtained, and the aforementioned steps are repeated. Based on the updated initial mapping relationship, new predictive linear interpolation coefficients are calculated, and new loss function values ​​are calculated. The iteration stops when the change in the loss function value is less than a preset threshold. The parameters corresponding to this point are taken as the optimal parameters, and the first mapping relationship is obtained. .in, Figure 5 A schematic diagram of an iterative curve of a loss function provided in this application is shown below. Figure 5 As shown, the horizontal axis represents the number of iterations, and the vertical axis represents the loss function value. The rapid decrease in the loss function value indicates that the parameters are rapidly optimized under the action of gradient descent, and the prediction error is greatly reduced. When the number of iterations exceeds 10, the curve gradually flattens and approaches 0, indicating that the error has been reduced to a minimum value, the magnitude of parameter updates becomes smaller and smaller, and finally a convergence state is reached. The parameters in the convergence state can be used as the aforementioned optimal parameters.

[0100] For example, Figure 6 This application provides a schematic diagram illustrating the correspondence between linear interpolation coefficients and braking pressure. Figure 6 (a) shows that the correspondence between the linear interpolation coefficients and the braking pressure can be obtained based on the actual linear interpolation coefficients corresponding to each actual braking pressure, i.e., the first mapping relationship. In this implementation, as follows: Figure 6 As shown in (b), the linear interpolation coefficients used under different braking pressures are different, which is significantly different from... Figure 2 The relationship between the linear interpolation coefficients and the braking pressure shown can better fit the nonlinear characteristics of different braking pressure ranges and improve the accuracy of braking pressure.

[0101] It should be noted that the above example is only for illustrating a linear relationship. The principle of non-linear relationships is similar and will not be elaborated here.

[0102] S206. Substitute the first mapping relationship into the preset linear interpolation equation to obtain the second mapping relationship.

[0103] For example, the above linear interpolation equation can be expressed as:

[0104] .

[0105] Furthermore, substituting the first mapping relationship, the second mapping relationship can be expressed as:

[0106] .

[0107] Furthermore, by combining like terms in the aforementioned formula, a nonlinear relationship between braking pressure and deceleration can be obtained.

[0108] S207, Obtain the target deceleration of the tractor.

[0109] For example, the target deceleration is the deceleration target value that the tractor needs to achieve, determined based on driving requirements.

[0110] In one example, the electronic device can obtain the pedal travel of the brake pedal and determine the target deceleration based on the preset correspondence between the pedal travel and the deceleration; alternatively, the vehicle's safety system can automatically generate the deceleration based on the driving conditions and then transmit it to the electronic device. The vehicle's safety system can be, for example, an anti-lock braking system, an automatic cruise control system, etc., which are not limited in this embodiment of the application.

[0111] S208. Based on the second mapping relationship and the target deceleration, determine the target braking pressure of the trailer.

[0112] For example, the target braking pressure refers to the pressure value that the trailer braking system needs to generate. For instance, the target braking pressure can be obtained by substituting the target deceleration into the second mapping relationship and solving the equation.

[0113] The method for determining trailer braking pressure provided in this application involves, after the tractor and trailer are connected, first acquiring multiple sets of sample data containing the actual braking pressure of the trailer and the corresponding actual deceleration of the tractor. Based on preset upper and lower boundary equations, the maximum and minimum deceleration corresponding to each set of data are calculated to obtain the actual linear interpolation coefficients. Then, the actual braking pressure is substituted into the initial mapping relationship to obtain the predicted linear interpolation coefficients. The parameters of the initial mapping relationship are adjusted to minimize the error using a gradient descent algorithm to obtain the first mapping relationship between the braking pressure and the linear interpolation coefficients. Subsequently, the first mapping relationship is substituted into the linear interpolation equation to obtain the second mapping relationship directly relating the tractor's deceleration and the trailer's braking pressure. Once the target deceleration of the tractor is obtained, substituting it into the second mapping relationship determines the corresponding target braking pressure of the trailer. This approach achieves two advantages. First, by leveraging sample data-driven model optimization, the second mapping relationship can better align with the nonlinear characteristics of different braking pressure ranges in the braking system, improving the accuracy of trailer braking pressure determination and reducing the disconnect in braking force distribution caused by existing global linear models. Second, the entire process is modeled based on data collected from the actual connected master-trailer combination, which can adapt to the differences in braking characteristics of trailers of different specifications. When changing trailers, data can be collected again to optimize the mapping relationship, thus improving the method's scenario adaptability.

[0114] The following describes how to perform trailer braking control based on the second mapping relationship. The executing entity in this embodiment can be a controller in the tractor unit. This controller can be an existing controller or domain controller in the tractor unit, or it can be an additional controller; this embodiment does not limit the specific controller used.

[0115] Figure 7 Flowchart of the trailer braking control method provided in this application Figure 1 ,like Figure 7 As shown, the method includes:

[0116] S301, Obtain the target deceleration of the tractor.

[0117] For example, the target deceleration is the deceleration target value that the tractor needs to achieve, determined based on driving requirements.

[0118] In one example, the controller can obtain the pedal travel of the brake pedal and determine the target deceleration based on the preset correspondence between the pedal travel and the deceleration; alternatively, the vehicle's safety system can automatically generate the deceleration based on the driving conditions and transmit it to the controller. The vehicle's safety system can be, for example, an anti-lock braking system, an automatic cruise control system, etc., which are not limited in this embodiment of the application.

[0119] S302. Based on the preset second mapping relationship and target deceleration, determine the target braking pressure of the trailer.

[0120] For example, the second mapping relationship is a pre-established nonlinear mathematical model stored in the controller, used to directly correlate the tractor deceleration with the trailer braking pressure. It is obtained by substituting the first mapping relationship between braking pressure and linear interpolation coefficients into the linear interpolation equation, thus accurately reflecting the actual nonlinear characteristics of the braking system. The target braking pressure refers to the pressure value required by the trailer braking system. The controller can substitute this target deceleration into the second mapping relationship to obtain the target braking pressure of the trailer.

[0121] Specifically, the target deceleration is substituted into the second mapping relationship to obtain the target braking pressure of the trailer. Referring to the second mapping relationship shown in step S206 above, the target deceleration is substituted, and after combining like terms in the second mapping relationship, it can be expressed as a quadratic equation in one variable. The target braking pressure is obtained by solving this quadratic equation.

[0122] S303. Control trailer braking based on target braking pressure.

[0123] For example, the controller can encapsulate the target braking pressure into a standardized control command and send it to the trailer's brake control valve through the electrical control signal line between the tractor and trailer. After receiving the command, the trailer's brake control valve adjusts the opening of the air intake circuit to control the pressure in the brake chamber as the target braking pressure, thereby pushing the brake pads to fit tightly against the brake drum to generate the corresponding braking force. This works in conjunction with the tractor's braking system to make the whole vehicle decelerate smoothly.

[0124] The trailer braking control method provided in this application first obtains the target deceleration of the tractor, then converts the target deceleration into a corresponding target braking pressure of the trailer based on a preset second mapping relationship, and finally drives the trailer to perform braking action based on the target braking pressure. In this way, by utilizing the pre-established second mapping relationship, the deceleration requirement of the tractor can be quickly and accurately converted into a braking pressure command for the trailer, avoiding the errors of a fixed linear model, improving the matching accuracy between braking pressure and actual requirements, and thus improving the control accuracy of trailer braking.

[0125] Figure 8 A schematic diagram of the device for determining trailer brake pressure provided in this application is shown below. Figure 8 As shown, the trailer brake pressure determining device 400 provided in this embodiment includes:

[0126] The acquisition module 401 is used to acquire multiple sets of sample data of the trailer after the tractor and trailer are connected; wherein, each set of sample data includes the actual braking pressure of the trailer and the actual linear interpolation coefficient; the actual linear interpolation coefficient represents the interpolation ratio between the preset upper boundary equation and the lower boundary equation; the boundary equation represents the boundary of the corresponding relationship between the braking pressure of the trailer and the deceleration of the tractor.

[0127] Module 402 is used to establish a first mapping relationship based on the actual braking pressure and actual linear interpolation coefficient in each set of sample data; wherein, the first mapping relationship represents the correspondence between the linear interpolation coefficient and the braking pressure;

[0128] The processing module 403 is used to substitute the first mapping relationship into the preset linear interpolation equation to obtain the second mapping relationship; wherein, the linear interpolation equation represents the correspondence between braking pressure and deceleration after using linear interpolation coefficients; the second mapping relationship is used to determine the target braking pressure of the trailer based on the target deceleration of the tractor.

[0129] In one possible implementation, module 402 is configured to:

[0130] For each set of sample data, the predicted linear interpolation coefficients are obtained based on the actual braking pressure of that set of sample data and the preset initial mapping relationship.

[0131] Based on the predicted linear interpolation coefficients and the actual linear interpolation coefficients of the sample data, the optimal parameters of the initial mapping relationship are determined, and the first mapping relationship is obtained.

[0132] In one possible implementation, the acquisition module 401 is used for:

[0133] Obtain the actual deceleration of the tractor corresponding to the actual braking pressure in this set of sample data;

[0134] Based on the actual braking pressure, upper boundary equation, and lower boundary equation in this set of sample data, the maximum deceleration and minimum deceleration corresponding to the actual braking pressure are determined respectively.

[0135] Based on the maximum deceleration, minimum deceleration, and actual deceleration, determine the actual linear interpolation coefficients in this set of sample data.

[0136] In one possible implementation, the device further includes a determining module for:

[0137] Obtain the target deceleration of the tractor unit;

[0138] Based on the second mapping relationship and the target deceleration, the target braking pressure of the trailer is determined.

[0139] The device for determining trailer braking pressure provided in this embodiment can execute the method provided in the above-described method embodiment. Its implementation principle and technical effect are similar, and will not be described in detail here.

[0140] Figure 9 A schematic diagram of the control device for trailer braking provided in this application is shown below. Figure 9As shown, the trailer braking control device 500 provided in this embodiment includes:

[0141] The acquisition module 501 is used to acquire the target deceleration of the tractor.

[0142] The determining module 502 is used to determine the target braking pressure of the trailer based on a preset second mapping relationship and the target deceleration; wherein the second mapping relationship is as described in any of the items in the first aspect;

[0143] Control module 503 is used to control trailer braking based on target braking pressure.

[0144] In one possible implementation, the determining module 502 is configured to:

[0145] Substituting the target deceleration into the second mapping relationship, the target braking pressure of the trailer is obtained by solving.

[0146] The trailer braking control device provided in this embodiment can execute the method provided in the above method embodiment. Its implementation principle and technical effect are similar, and will not be described in detail here.

[0147] Figure 10 A schematic diagram of the structure of the electronic device provided in this application. Figure 10 As shown, the electronic device 600 provided in this embodiment includes at least one processor 601 and a memory 602. Optionally, the electronic device 600 further includes a communication component 603. The processor 601, memory 602, and communication component 603 are connected via a bus. This electronic device may be the controller described in the foregoing embodiments.

[0148] In a specific implementation, at least one processor 601 executes computer execution instructions stored in memory 602, causing at least one processor 601 to perform the above-described method.

[0149] The specific implementation process of processor 601 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0150] In the above embodiments, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0151] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage device.

[0152] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings are not limited to a single bus or a single type of bus.

[0153] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method.

[0154] This application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the above-described method.

[0155] The aforementioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0156] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in an Application Specific Integrated Circuit (ASIC). Alternatively, the processor and the readable storage medium can exist as discrete components in the device.

[0157] The division of units is merely a logical functional division; in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or units, and may be electrical, mechanical, or other forms.

[0158] The units described 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.

[0159] In addition, the functional units in the various embodiments of the present invention 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.

[0160] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0161] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0162] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A method of determining trailer brake pressure, characterized by, The method includes: After the tractor and trailer are connected, multiple sets of sample data of the trailer are acquired; each set of sample data includes the actual braking pressure of the trailer and the actual linear interpolation coefficient; the actual linear interpolation coefficient represents the interpolation ratio between the preset upper boundary equation and the lower boundary equation; the boundary equation represents the boundary of the corresponding relationship between the braking pressure of the trailer and the deceleration of the tractor. Based on the actual braking pressure and the actual linear interpolation coefficient in each set of sample data, a first mapping relationship is established; wherein, the first mapping relationship characterizes the correspondence between the linear interpolation coefficient and the braking pressure; Substituting the first mapping relationship into the preset linear interpolation equation, a second mapping relationship is obtained; wherein, the linear interpolation equation characterizes the correspondence between braking pressure and deceleration after using linear interpolation coefficients; the second mapping relationship is used to determine the target braking pressure of the trailer based on the target deceleration of the tractor.

2. The method of claim 1, wherein, The establishment of a first mapping relationship based on the actual braking pressure and the actual linear interpolation coefficient in each set of sample data includes: For each set of sample data, the predicted linear interpolation coefficients are obtained based on the actual braking pressure of that set of sample data and the preset initial mapping relationship. Based on the predicted linear interpolation coefficients and the actual linear interpolation coefficients of the sample data, the optimal parameters of the initial mapping relationship are determined, and the first mapping relationship is obtained.

3. The method of claim 1, wherein, Obtain the actual linear interpolation coefficients for each set of sample data, including: Obtain the actual deceleration of the tractor corresponding to the actual braking pressure in this set of sample data; Based on the actual braking pressure, the upper boundary equation, and the lower boundary equation in this set of sample data, the maximum deceleration and the minimum deceleration corresponding to the actual braking pressure are determined respectively. The actual linear interpolation coefficients in the sample data are determined based on the maximum deceleration, the minimum deceleration, and the actual deceleration.

4. The method according to any one of claims 1 to 3, characterized in that, The method further includes: Obtain the target deceleration of the tractor; Based on the second mapping relationship and the target deceleration, the target braking pressure of the trailer is determined.

5. A control method of trailer braking, characterized by, The method is applied to the controller of a tractor unit, which is connected to a trailer; it includes: Obtain the target deceleration of the tractor; The target braking pressure of the trailer is determined based on the preset second mapping relationship and the target deceleration; wherein the second mapping relationship is the second mapping relationship as described in any one of claims 1-4; The trailer brakes are controlled based on the target braking pressure.

6. The method of claim 5, wherein, Determining the target braking pressure of the trailer based on the preset second mapping relationship and the target deceleration includes: Substituting the target deceleration into the second mapping relationship, the target braking pressure of the trailer is obtained by solving.

7. A trailer brake pressure determination device, characterized by The device includes: The acquisition module is used to acquire multiple sets of sample data of the trailer after the tractor and trailer are connected; wherein each set of sample data includes the actual braking pressure of the trailer and the actual linear interpolation coefficient; the actual linear interpolation coefficient represents the interpolation ratio between the preset upper boundary equation and the lower boundary equation; the boundary equation represents the boundary of the corresponding relationship between the braking pressure of the trailer and the deceleration of the tractor. A module is established to establish a first mapping relationship based on the actual braking pressure and the actual linear interpolation coefficient in each set of sample data; wherein the first mapping relationship characterizes the correspondence between the linear interpolation coefficient and the braking pressure; The processing module is used to substitute the first mapping relationship into a preset linear interpolation equation to obtain a second mapping relationship; wherein the linear interpolation equation represents the correspondence between braking pressure and deceleration after using linear interpolation coefficients; the second mapping relationship is used to determine the target braking pressure of the trailer based on the target deceleration of the tractor.

8. A control device for trailer braking, characterized in that The device is used as a controller for a tractor unit connected to a trailer; the device includes: The acquisition module is used to acquire the target deceleration of the tractor. The determining module is configured to determine the target braking pressure of the trailer based on a preset second mapping relationship and the target deceleration; wherein the second mapping relationship is the second mapping relationship as described in any one of claims 1-4; The control module is used to control the trailer brake based on the target braking pressure.

9. An electronic device, comprising: include: Memory, processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory, causing the processor to perform the method as described in any one of claims 1-6.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method as described in any one of claims 1-6.

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