Brake friction coupling analysis system based on automobile brake shoe

Abstract

The invention discloses a brake friction coupling analysis system based on an automobile brake shoe, and the system comprises a model construction unit which is used for constructing a friction contact model; the load acquisition unit and the pressure distribution solving unit are used for inputting the braking force load array into the friction contact model so as to solve the contact pressure distribution; the friction coefficient acquisition unit is used for acquiring the friction coefficient of the friction plate; the distribution calculation unit is used for calculating friction force distribution of the contact surface at different time points according to the friction coefficient and the contact pressure distribution; the space-time distribution acquisition unit is used for acquiring friction force distribution of a plurality of contact surfaces at different time points to obtain a space-time distribution array of braking friction in the braking process; a mass center position is extracted from space coordinates of a plurality of contact surfaces, a space index is established, friction force data of each contact surface at different moments are fused, and a braking friction space-time distribution array with time and space information is formed.

Description

TECHNICAL FIELD

[0001] The present application relates to a brake coupling system, in particular to a brake friction coupling analysis system based on automobile brake shoes. BACKGROUND

[0002] In the traditional automobile brake system, the friction coupling behavior between the brake shoe and the friction plate directly affects the brake performance, thermal stability and wear uniformity. However, the existing technology usually uses static or semi-empirical methods to analyze the friction characteristics during braking, which is difficult to accurately reflect the dynamic changes of the contact pressure distribution and the evolution law of the friction force in the time and space dimensions during the actual braking process. The patent document with patent number CN110614987A discloses the detection of friction brake failure, which can generate a sensing signal indicating brake failure when the detected vibration and the detected hydraulic brake pressure change are greater than their corresponding threshold values.

[0003] However, under complex working conditions, the contact state (such as face-to-face contact, point contact) between the brake shoe and the friction plate, the surface geometric characteristics (such as curvature, roughness) and the external load (hydraulic pressure, thrust direction and size) will significantly affect the friction behavior. In addition, since the friction coefficient changes with temperature, relying only on a fixed friction coefficient for simulation analysis will cause the calculation results to deviate from the true situation, and cannot effectively support the structure optimization and failure prediction of the brake system. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides a brake friction coupling analysis system based on automobile brake shoes, which solves the technical problems proposed in the background art by constructing a friction coupling space-time distribution array of automobile brake shoes during braking.

[0005] To achieve the above purpose, the present application is realized by the following technical solutions:

[0006] A brake friction coupling analysis system based on automobile brake shoes, comprising:

[0007] A model construction unit for constructing a friction contact model, wherein the friction contact model is used to describe the contact surface between the brake shoe and the friction plate;

[0008] A load acquisition unit for acquiring a brake force load array applied to the brake shoe during actual braking;

[0009] A pressure distribution solving unit for inputting the brake force load array into the friction contact model to solve the contact pressure distribution;

[0010] A friction coefficient acquisition unit for acquiring the friction coefficient of the friction plate;

[0011] a distribution calculation unit configured to calculate a friction force distribution of the contact surface at different time points according to the friction coefficient and the contact pressure distribution;

[0012] a space-time distribution acquisition unit configured to acquire the friction force distribution of the contact surface at different time points to obtain a space-time distribution array of the brake friction during the braking process.

[0013] In some specific embodiments, the friction contact model is constructed, including:

[0014] S1-1, constructing a first finite element model of the brake shoe;

[0015] S1-2, constructing a second finite element model of the friction plate;

[0016] S1-3, matching the first finite element model of the brake shoe with the second finite element model of the friction plate to generate the friction contact model.

[0017] In some specific embodiments, the first finite element model of the brake shoe is constructed, including:

[0018] S1-1-1, acquiring first geometric parameters of the brake shoe;

[0019] S1-1-2, inputting the first geometric parameters of the brake shoe into a finite element analysis software to create a three-dimensional geometric body of the brake shoe;

[0020] S1-1-3, performing meshing on the three-dimensional geometric body of the brake shoe to obtain the first finite element model with a plurality of discretized meshes.

[0021] In some specific embodiments, the second finite element model of the friction plate is constructed, including:

[0022] S1-2-1, acquiring second geometric parameters of the friction plate in contact with the brake shoe;

[0023] S1-2-2, inputting the second geometric parameters into a finite element analysis software to construct a three-dimensional geometric body of the friction plate;

[0024] S1-2-3, performing meshing on the three-dimensional geometric body of the friction plate to obtain the second finite element model with a plurality of discretized meshes.

[0025] In some specific embodiments, the first finite element model of the brake shoe is matched with the second finite element model of the friction plate to generate the friction contact model, including:

[0026] S1-3-1, marking the contact surface of the brake shoe and the contact surface of the friction plate from the first geometric parameters and the second geometric parameters, respectively;

[0027] S1-3-2, contact surface index is established for the contact surface of the marked brake shoe and the contact surface of the friction plate;

[0028] S1-3-3, according to the contact surface index, the corresponding contact surface characteristics of the brake shoe in the first geometric parameter are obtained, and the corresponding contact surface characteristics of the friction plate in the second geometric parameter are obtained;

[0029] S1-3-4, according to the corresponding contact surface characteristics of the brake shoe in the first geometric parameter and the corresponding contact surface characteristics of the friction plate in the second geometric parameter, the geometric characteristics of the contact surface are defined;

[0030] In some specific embodiments, the brake force load array is input into the friction contact model to solve the contact pressure distribution, including:

[0031] S3-1, the brake force load array is distributed to a plurality of contact surfaces of the friction contact model; wherein each contact surface is distributed with brake force load;

[0032] S3-2, the contact surface distributed with brake force load is anchored, and the contact surface shape, size and contact point number thereof are obtained from the geometric characteristics of the contact surface;

[0033] S3-3, according to the contact surface shape, size and contact point number, and the distributed brake force load, the contact pressure of the contact surface is calculated;

[0034] S3-4, the contact pressures of the plurality of contact surfaces are obtained, and finite element analysis is used to solve the contact pressure distribution.

[0035] In some specific embodiments, according to the friction coefficient and the contact pressure distribution, the friction force distribution of the contact surface at different time points is calculated, including:

[0036] S5-1: obtaining the contact pressure distribution of the contact surface at different time points

[0037] S5-2: obtaining the temperature distribution of the contact surface at different time points

[0038] S5-3: according to the temperature distribution of the contact surface at different time points, the corresponding friction coefficient of the friction plate is collected

[0039] S5-4: according to the friction coefficient of the friction plate and the contact pressure distribution, the friction force distribution of the contact surface at different time points is calculated;

[0040] In some specific embodiments, the friction force distribution of a plurality of contact surfaces at different time points is obtained, and the space-time distribution array of the brake friction in the braking process is obtained, including:

[0041] S6-1, obtain the contact surface index of the plurality of contact surfaces;

[0042] S6-2, according to the contact surface index of the plurality of contact surfaces, obtain the friction force distribution of the plurality of contact surfaces at different time points;

[0043] S6-3, according to the contact surface index of the plurality of contact surfaces, obtain the spatial coordinates of the plurality of contact surfaces;

[0044] S6-4, according to the spatial coordinates of the plurality of contact surfaces, generate a spatial index of each contact surface; wherein the spatial index represents the centroid coordinates of the spatial coordinates of each contact surface;

[0045] S6-5, data fusion of the spatial index and the friction force distribution of the contact surface at different time points, to obtain the space-time distribution array of the brake friction in the brake process.

[0046] The present application has the following beneficial effects:

[0047] The present application can accurately represent the contact state and contact area distribution between the brake shoe and the friction plate by constructing a friction contact model including the geometric characteristics of the contact surface of the brake shoe and the friction plate. By combining the first and second geometric parameters of the brake shoe and the friction plate, the respective three-dimensional finite element models are established, and the grid refinement is performed in the contact area, which improves the calculation accuracy of the contact pressure. In terms of load input, the system collects the brake force load array composed of the hydraulic pressure output by the cylinder during the actual braking process, the direction and size of the piston thrust, and the application rate, and maps it to each contact surface, realizing the dynamic solution of the contact pressure distribution. This process calculates the contact pressure by anchoring each contact surface and combining its shape, area, and number of contact points. In terms of friction behavior modeling, the system introduces the time dimension to obtain the contact pressure distribution and temperature distribution at different time points, and according to the temperature-friction coefficient relationship, the friction coefficient at the corresponding time is obtained, so that the friction force of each contact unit at different times is calculated. Finally, the system extracts the centroid position of the spatial coordinates of the plurality of contact surfaces and establishes a spatial index, and fuses the friction force data of each contact surface at different time points to form a brake friction space-time distribution array with time and space information. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 The structure block diagram of the brake friction coupling analysis system based on the automobile brake shoe of the application;

[0049] Figure 2 The flowchart of the brake friction coupling analysis system based on the automobile brake shoe of the application;

[0050] Figure 3 The construction flowchart of the friction contact model of the application;

[0051] Figure 4 The generation flowchart of the space-time distribution array of the application is shown. DETAILED DESCRIPTION

[0052] The technical solutions in the embodiments of the application will be clearly and completely described in connection with the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the application.

[0053] Embodiment 1: refer to Figures 1-4 The application provides a brake friction coupling analysis system based on a brake shoe of a vehicle, comprising:

[0054] A model construction unit is configured to construct a friction contact model, wherein the friction contact model is configured to describe a contact surface between the brake shoe and the friction plate.

[0055] Exemplarily, the friction contact model comprises geometric features of the contact surface shape, distribution of the contact area, and types of the friction contact (such as face-face contact, point contact, etc.).

[0056] A load acquisition unit is configured to acquire a brake force load array applied to the brake shoe in a real brake process.

[0057] The brake force load array comprises hydraulic pressure output by a cylinder, a piston thrust direction, a piston thrust size, and an application rate. Exemplarily, the hydraulic pressure, the thrust direction, and the application rate are collected in real time by a pressure sensor and a force sensor in a vehicle brake system.

[0058] A pressure distribution solving unit is configured to input the brake force load array to the friction contact model to solve a contact pressure distribution.

[0059] A friction coefficient acquisition unit is configured to acquire a friction coefficient of the friction plate.

[0060] A distribution calculation unit is configured to calculate a friction force distribution of the contact surface at different time points according to the friction coefficient and the contact pressure distribution.

[0061] A space-time distribution acquisition unit is configured to acquire friction force distributions of a plurality of contact surfaces at different time points to obtain a space-time distribution array of brake friction in a brake process.

[0062] The embodiment realizes dynamic solution of the contact pressure distribution between the brake shoe and the friction plate by constructing a friction contact model and combining the brake force load array obtained in the real braking process. On this basis, the friction force distribution of the contact surface at different time points is calculated by further combining the time sequence changes of the friction coefficient and the contact pressure. Finally, the friction force data of multiple contact surfaces in the time and space dimensions are integrated to form the braking friction space-time distribution array in the braking process, so that the change process of the friction force of each contact area in the braking process can be analyzed. Through the space-time distribution array, a basic data format for visual display and data analysis can be formed to realize dynamic recording of the friction behavior change with time and space in the braking process.

[0063] In the embodiment, the step S1 specifically comprises:

[0064] S1-1, constructing a first finite element model of the brake shoe;

[0065] S1-2, constructing a second finite element model of the friction plate;

[0066] S1-3, matching the first finite element model of the brake shoe with the second finite element model of the friction plate to generate a friction contact model.

[0067] The embodiment generates a friction contact model that can represent the braking friction coupling of the automobile brake shoe by constructing the finite element models of the brake shoe and the friction plate and matching the models.

[0068] Further, the step S1-1 specifically comprises:

[0069] S1-1-1, obtaining first geometric parameters of the brake shoe;

[0070] Specifically, the first geometric parameters include the size, curvature radius, thickness, assembly angle and surface roughness of the brake shoe. Exemplarily, the size of the brake shoe can be obtained by a three-dimensional laser scanner or a numerical control measuring device, and the curvature radius, thickness and the like can be extracted by a measuring tool or a design drawing.

[0071] S1-1-2, inputting the first geometric parameters of the brake shoe into a finite element analysis software to create a three-dimensional geometric body of the brake shoe;

[0072] Exemplarily, if the brake shoe is an arc-shaped structure with curvature, the "create entity" function in the finite element software is used to input the radius, thickness and other parameters to generate a circular arc brake shoe model.

[0073] S1-1-3, performing meshing on the three-dimensional geometric body of the brake shoe to obtain a first finite element model with a plurality of discretized meshes.

[0074] Exemplarily, the three-dimensional geometry of the brake shoe is meshed by the meshing tool of the finite element analysis software. According to the calculation accuracy requirement, a suitable unit type (such as tetrahedron, hexahedron, etc.) is selected, and the mesh size is defined.

[0075] In the contact area and stress concentration area (such as the brake contact surface of the brake shoe), finer meshing is adopted to improve the calculation accuracy; in other areas, coarser meshing is adopted to improve the calculation efficiency.

[0076] Further, the step S1-2 specifically comprises:

[0077] S1-2-1: Obtain the second geometric parameters of the friction plate in contact with the brake shoe

[0078] The second geometric parameters include: the size of the friction plate contact surface, such as length and width; the overall thickness of the friction plate, which affects the friction performance and heat conduction; the fitting contour: the shape or contour of the friction plate surface, which is used to cooperate with the contact surface of the brake shoe; the surface roughness: the roughness of the friction plate surface directly affects the friction coefficient and wear performance.

[0079] Exemplarily, the geometric data of the friction plate can be obtained from the actual part by a three-dimensional scanner, CAD model import, or manual measurement (such as a caliper).

[0080] S1-2-2: Import the second geometric parameters into the finite element analysis software to construct a three-dimensional geometry of the friction plate;

[0081] S1-2-3: Mesh the three-dimensional geometry of the friction plate to obtain a second finite element model with a plurality of discrete meshes.

[0082] In this embodiment, by constructing a three-dimensional geometric model of the friction plate and through fine meshing, the analysis of the friction plate can produce high-precision results in contact force calculation. For the friction plate contact surface area, fine meshing can ensure more accurate stress and friction force calculation in the contact area.

[0083] Further, the step S1-3 specifically comprises:

[0084] S1-3-1, mark the contact surface of the brake shoe and the contact surface of the friction plate from the first geometric parameters and the second geometric parameters, respectively;

[0085] Specifically, according to the size and radius of curvature of the brake shoe, the area in contact with the friction plate is marked in the first finite element model of the brake shoe, which is defined as the contact surface of the brake shoe. According to the geometric characteristics (such as the size of the friction surface, the thickness) of the friction plate, the area in contact with the brake shoe is marked in the second finite element model of the friction plate, which is defined as the contact surface of the friction plate.

[0086] Exemplarily, if the brake shoe is circular arc-shaped and the part in contact with the friction plate is an arc-shaped area, the range of the arc-shaped area is calculated through geometric parameters and marked as a contact surface. The contact surface of the friction plate can be defined by its size and fitting contour.

[0087] S1-3-2, a contact surface index is established for the contact surface of the marked brake shoe and the contact surface of the friction plate;

[0088] Specifically, the contact surface index is represented as assigning a unique identifier to each contact surface area so as to identify each contact surface in the finite element model.

[0089] Exemplarily, the contact surface of the brake shoe is named as C1, C2,... and the contact surface of the friction plate is named as F1, F2,.... Then, the contact surface index is completed by using the geometric features of the contact area in the geometric model, such as position, shape, etc.

[0090] S1-3-3, according to the contact surface index, the corresponding contact surface features of the brake shoe in the first geometric parameters are obtained, and the corresponding contact surface features of the friction plate in the second geometric parameters are obtained;

[0091] Through the contact surface index, the contact surface features of the brake shoe and the friction plate are extracted. The contact surface features of the brake shoe include the shape, size, curvature, etc. of the contact surface, and the features of the area in contact with the friction plate. The contact surface features of the friction plate include the geometric features of the contact area of the friction plate, such as the shape, size, surface roughness, etc. of the friction surface.

[0092] Exemplarily, if the contact surface of the brake shoe is a circular arc surface, the corresponding contact surface features include the radius, curvature and contact position. The contact surface of the friction plate includes the length, width, surface roughness, etc. of the contact area.

[0093] S1-3-4, according to the corresponding contact surface features of the brake shoe in the first geometric parameters and the corresponding contact surface features of the friction plate in the second geometric parameters, the geometric features of the contact surface are defined;

[0094] According to the obtained contact surface features, the geometric features of the contact surface are further defined.

[0095] The geometric features of the contact surface include the contact surface area, contact line shape, contact angle, etc. geometric parameters.

[0096] Exemplarily, if the contact surface of the brake shoe is a circular arc and the contact surface of the friction plate is a plane, the contact surface geometric features can be described as the contact area, contact edge shape and contact angle of the arc surface of the brake shoe and the plane of the friction plate in the contact area.

[0097] In the embodiment, the step S3 specifically comprises:

[0098] S3-1, distributing the brake force load array to a plurality of contact surfaces of the friction contact model; wherein each contact surface is assigned a brake force load;

[0099] Specifically, step S3-1 includes:

[0100] Load distribution: distributing the input brake force load array to each contact surface of the friction contact model according to the contact surface geometry in the contact model. Each contact surface bears different sizes of load according to its size, shape and position.

[0101] Load mapping: by calculating the contact area of the model, the applied brake force is distributed to the contact points according to the grid elements on the contact surface, ensuring the uniformity of load distribution.

[0102] S3-2, anchoring the contact surface assigned with the brake force load and obtaining its contact surface shape, size and number of contact points from the geometric features of the contact surface;

[0103] Specifically, step S3-2 includes:

[0104] Anchoring the contact surface: determining the specific position of each contact surface in the model and "anchoring" the contact surface, which means assigning each contact surface with corresponding geometric features and contact points.

[0105] Obtaining contact surface features: extracting geometric features from the marked contact surface, including the shape of the contact surface (such as plane, circle, arc, etc.), size, and number of contact points.

[0106] S3-3, calculating the contact pressure of the contact surface according to the contact surface shape, size and number of contact points, and the assigned brake force load;

[0107] Wherein, the contact pressure is represented as: for each contact surface, the contact pressure of the brake force load on the unit area of the contact surface. That is, the contact pressure is calculated by the ratio of the applied brake force load on each contact element to the area of the contact element, specifically calculated as:

[0108]

[0109] Wherein, P i represents the contact pressure on the contact element i, F i is the brake force load assigned to the contact element i, A i is the contact area of the contact element i.

[0110] S3-4, obtaining the contact pressure of the plurality of contact surfaces and using finite element analysis to solve the contact pressure distribution.

[0111] The contact pressure of the obtained several contact surfaces is input into the finite element analysis software for global solving. The distribution of the contact pressure on the contact surface is solved by the finite element analysis, and the specific contact pressure of each contact element is obtained.

[0112] In this embodiment, the step S5 specifically comprises:

[0113] S5-1: Obtain the contact pressure distribution of the contact surface at different time points

[0114] Specifically, step S5-1 comprises:

[0115] Contact pressure acquisition: Through the contact pressure distribution solving result in the aforementioned step S3-4, the contact pressure distribution of the contact surface at different time points is obtained.

[0116] Time sequence change of contact pressure: With the progress of the braking process, the contact pressure changes with time, and the contact pressure data at each time point needs to be recorded and saved to ensure that the data accurately reflect the load and temperature changes in the braking process.

[0117] Exemplarily, through the output of the sensor or the simulation model, the contact pressure at each time point is tracked and recorded in real time.

[0118] S5-2: Obtain the temperature distribution of the contact surface at different time points

[0119] Specifically, step S5-2 comprises:

[0120] Temperature distribution measurement: Obtain the temperature data during the braking process, especially the temperature change at the contact surface at different time points.

[0121] Temperature monitoring device: Use thermocouples, infrared sensors and other temperature measurement devices to obtain the temperature distribution of the contact surface during the braking process.

[0122] Exemplarily, an infrared sensor is used for contact surface temperature monitoring, or a thermocouple is embedded in the contact surface to obtain accurate temperature distribution data.

[0123] S5-3: According to the temperature distribution of the contact surface at different time points, the friction coefficient corresponding to the friction plate is collected

[0124] Specifically, step S5-2 comprises:

[0125] Friction coefficient and temperature relationship: The friction coefficient usually changes with the change of temperature. Through experiments or material property data, the friction coefficient of the friction plate at different temperatures is obtained.

[0126] Temperature-friction coefficient data collection: According to the temperature distribution data obtained in S5-2, the friction coefficient at the corresponding temperature is found or calculated.

[0127] For example, by consulting the temperature-friction coefficient table of the friction plate, or using the experimental data in the material library, the corresponding friction coefficient value at different temperatures is obtained.

[0128] S5-4: According to the friction coefficient and contact pressure distribution of the friction plate, the friction force distribution of the contact surface at different time points is calculated;

[0129] Specifically, step S5-2 includes:

[0130] Friction force calculation formula: according to the known contact pressure and friction coefficient, the following formula is used to calculate the friction force of the contact surface at different time points:

[0131] F friction (t) = μ(t) · P(t);

[0132] P(t) is the contact pressure of the contact surface at time t, μ(t) is the friction coefficient at time t, F friction (t) is the calculated friction force.

[0133] Friction force distribution calculation: by calculating all contact units, the friction force distribution on the contact surface is obtained. The friction force is calculated for each contact unit at time points, and complete friction force time series data is formed.

[0134] In this embodiment, the step S6 specifically includes:

[0135] S6-1, obtaining the contact surface index of a plurality of contact surfaces;

[0136] S6-2, according to the contact surface index of the plurality of contact surfaces, obtaining the friction force distribution of the plurality of contact surfaces at different time points;

[0137] Specifically, step S6-2 includes:

[0138] Friction force distribution extraction: based on the friction force distribution data obtained in S7, the friction force is distributed to the corresponding contact surface according to the contact surface index. The friction force of each contact surface at each time point is calculated by the friction force formula in the foregoing steps.

[0139] Time series friction force data: for each contact surface, the friction force distribution of each contact surface at different time points is stored through time series data. The friction force at each time point will be matched with the contact surface index.

[0140] S6-3, according to the contact surface index of the plurality of contact surfaces, obtaining the spatial coordinates of the plurality of contact surfaces;

[0141] Specifically, step S6-3 includes:

[0142] Space coordinate extraction: Extract the position of each contact surface in three-dimensional space (space coordinates) from the contact surface geometry data. The space coordinates corresponding to each contact surface are determined by its geometric features (such as circular, arc, etc.) and its position in the finite element model.

[0143] Contact surface geometry analysis: For each contact surface, record its position data such as centroid coordinates or boundary coordinates.

[0144] S6-4, according to the space coordinates of several contact surfaces, generate the space index of each contact surface; wherein the space index represents the centroid coordinates of the space coordinates of each contact surface;

[0145] Specifically, step S6-4 includes:

[0146] Space index creation: According to the space coordinates of the contact surface, calculate the centroid coordinates of each contact surface in three-dimensional space. The centroid coordinates are usually the geometric center point of the contact surface, which is used to represent the position of the contact surface.

[0147] Space index assignment: Assign a space index to each contact surface to identify its position in three-dimensional space, ensuring that the contact surface can be quickly located in the model through the space index

[0148] S6-5, data fusion of the space index and the friction distribution of the contact surface at different time points, to obtain the space-time distribution array of the brake friction in the brake process.

[0149] The space-time distribution array needs to combine the friction data of each contact surface at each time point with the space coordinates of the contact surface.

[0150] The friction of each contact surface at a certain time point can be represented as a three-dimensional data point, where the space coordinates represent the position of the contact surface, and the friction distribution represents the friction of the contact surface at that time point.

[0151] Specifically, for each contact surface C1, the data at time point t1 can be represented as a multi-dimensional vector, i.e. space coordinates and friction at that time point; and the friction of all space coordinates at time points is the space-time distribution array.

[0152] Use visualization tools (such as MATLAB, Python, etc.) to graphically display the generated space-time distribution array, to obtain a dynamic display distribution diagram of the friction changing with time and space, which can help analyze the friction distribution of different contact areas in the brake process and the change over time.

[0153] The space-time distribution array takes the contact surface centroid coordinates as the three-dimensional space index, takes the braking time as the sequence axis, and takes the friction force value on the contact element as the data body, to construct a multi-dimensional data structure with geometric mapping relationship; each data point in the data structure corresponds to the friction force response value of the brake shoe and the friction plate at a specific time and a specific position, and a one-to-one mapping relationship is established between the contact element number and the spatial coordinates in the finite element model; thus, the spatial distribution and time evolution of the friction behavior during braking are accurately characterized, which can be used to identify local high stress areas, friction non-uniformity characteristics and dynamic friction response hysteresis and the like.

[0154] The embodiment indexes the spatial coordinates of multiple contact surfaces, and combines the friction force distribution data at different time points for fusion analysis, to construct a brake friction distribution array with space-time characteristics. The array takes the contact surface centroid as the space index, takes the time as the sequence axis, and takes the friction force as the numerical dimension, to completely characterize the dynamic evolution process of the friction force of each contact area during braking. Through the space-time distribution array, the friction force concentration area, the friction instability area and the potential thermal damage risk area can be intuitively identified, thereby providing visual support for the safety evaluation of the automobile braking system, the selection of friction materials and the optimization of the structure.

[0155] The above embodiments can be realized wholly or partially by software, hardware, firmware or any combination thereof. When realized by software, the above embodiments can be realized wholly or partially in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the processes or functions described in the embodiments of the present application are wholly or partially generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another, for example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center by wired (such as infrared, wireless, microwave, etc.) mode.

[0156] The computer-readable storage medium can be any available medium accessible by a computer or a data storage device such as a server, data center and the like containing a set of one or more available media. The available media can be a magnetic medium (such as a floppy disk, a hard disk, a magnetic tape), an optical medium (such as a DVD), or a semiconductor medium. The semiconductor medium can be a solid state disk.

[0157] In several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other ways. For example, the above-described device embodiments are merely illustrative. For example, multiple units or components can be combined or integrated into another system, or some features can be omitted or not implemented. In addition, the coupling or direct coupling or communication connection between the shown or discussed can be indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0158] The above descriptions are merely specific embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered within the protection scope of the present application.

Claims

1. A brake friction coupling analysis system based on automobile brake shoes, characterized in that: include: A model building unit, used for building a friction contact model; wherein the friction contact model is used for describing the contact surface between the brake shoe and the friction plate; A load acquisition unit, configured to acquire an array of braking force loads applied to the brake shoe during an actual braking process; A pressure distribution solving unit is used to input the braking force load array into the friction contact model to solve the contact pressure distribution; a friction coefficient obtaining unit, configured to obtain the friction coefficient of the friction plate; a distribution calculation unit, configured to calculate the friction force distribution of the contact surface at different time points based on the friction coefficient and the contact pressure distribution; The spatiotemporal distribution acquisition unit is used to acquire the friction force distribution of a plurality of contact surfaces at different time points, and obtain the spatiotemporal distribution array of the braking friction during the braking process.

2. The brake friction coupling analysis system based on automobile brake shoes according to claim 1 is characterized in that: Construct friction contact models, including: S1-1, constructing a first finite element model of the brake shoe; S1-2, constructing a second finite element model of the friction plate; S1-3. Match the first finite element model of the brake shoe with the second finite element model of the friction plate to generate a friction contact model.

3. The brake friction coupling analysis system based on automobile brake shoes according to claim 2 is characterized in that: Construct the first finite element model of the brake shoe, including: S1-1-1. Obtaining first geometric parameters of the brake shoe; S1-1-2. Import the first geometric parameters of the brake shoe into the finite element analysis software to create a three-dimensional geometric body of the brake shoe; S1-1-3. Perform mesh division on the three-dimensional geometric body of the brake shoe to obtain a first finite element model having a plurality of discretized meshes.

4. The brake friction coupling analysis system based on automobile brake shoes according to claim 2 is characterized in that: Construct the second finite element model of the friction plate, including: S1-2-1: Obtain the second geometric parameters of the friction plate in contact with the brake shoe S1-2-2: Connecting the second geometric parameters to finite element analysis software to construct a three-dimensional geometric body of the friction plate; S1-2-3: Meshing is performed on the three-dimensional geometric body of the friction plate to obtain a second finite element model having a plurality of discretized meshes.

5. The brake friction coupling analysis system based on automobile brake shoes according to claim 2, characterized in that: The first finite element model of the brake shoe is matched with the second finite element model of the friction plate to generate a friction contact model, including: S1-3-1. Mark the contact surface of the brake shoe and the contact surface of the friction plate based on the first and second geometric parameters, respectively. S1-3-2. Create a contact surface index for the marked contact surface of the brake shoe and the contact surface of the friction plate; S1-3-3. Obtaining, based on the contact surface index, a contact surface feature of the brake shoe corresponding to the first geometric parameter, and obtaining a contact surface feature of the friction plate corresponding to the second geometric parameter; S1-3-4. Define the geometric characteristics of the contact surface according to the contact surface characteristics of the brake shoe corresponding to the first geometric parameter and the contact surface characteristics of the friction plate corresponding to the second geometric parameter.

6. The brake friction coupling analysis system based on automobile brake shoes according to claim 5, characterized in that: Input the braking force load array to the friction contact model to solve for the contact pressure distribution, including: S3-1, distributing a braking force load array to a plurality of contact surfaces of a friction contact model; wherein each contact surface is assigned a braking force load; S3-2. Anchoring the contact surface to which the braking force load is distributed, and obtaining the contact surface shape, size, and number of contact points from the geometric features of the contact surface; S3-3. Calculating the contact pressure of the contact surface according to the shape, size, and number of contact points of the contact surface, as well as the allocated braking force load; S3-4. Obtain contact pressures of the plurality of contact surfaces, and use finite element analysis to solve the contact pressure distribution.

7. The brake friction coupling analysis system based on automobile brake shoes according to claim 6, characterized in that: Calculating the friction force distribution of the contact surface at different time points according to the friction coefficient and the contact pressure distribution, including: S5-1: Obtain contact pressure distribution on the contact surface at different time points S5-2: Obtaining the temperature distribution of the contact surface at different time points S5-3: Collect the friction coefficient corresponding to the friction plate based on the temperature distribution of the contact surface at different time points S5-4: Calculate the friction force distribution of the contact surface at different time points based on the friction coefficient and contact pressure distribution of the friction plate.

8. The brake friction coupling analysis system based on automobile brake shoes according to claim 7 is characterized in that: Obtain the friction force distribution of several contact surfaces at different time points to obtain the spatiotemporal distribution array of the braking friction during the braking process, including: S6-1. Obtain contact surface indexes of several contact surfaces; S6-2. Obtaining friction force distributions of the plurality of contact surfaces at different time points according to the contact surface indexes of the plurality of contact surfaces; S6-3. Obtaining spatial coordinates of the plurality of contact surfaces according to the contact surface indexes of the plurality of contact surfaces; S6-4. Generate a spatial index for each contact surface based on the spatial coordinates of the plurality of contact surfaces; wherein the spatial index is represented by the coordinates of the centroid of the spatial coordinate geometry of each contact surface; S6-5. Perform data fusion on the spatial index and the friction force distribution of the contact surface at different time points to obtain a spatiotemporal distribution array of the braking friction during the braking process.

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