Electronic parking brake system function safety evaluation method under longitudinal slope condition

Abstract

The embodiment of the invention discloses a function safety evaluation method for an electronic parking brake system under a longitudinal slope condition. The method comprises the following steps: constructing a function safety test case library of the electronic parking brake system under a longitudinal slope road surface; constructing a function safety evaluation index of the electronic parking brake system; constructing a function safety evaluation model of the electronic parking brake system, and processing the function safety evaluation model based on an analytic hierarchy process to obtain the weight of each function safety evaluation index; function safety evaluation index scores of the tested vehicle under the test working condition are determined, the function safety evaluation index scores are weighted, and an evaluation result of the tested vehicle under the test working condition is obtained. Compared with a gradient-free test scene, a longitudinal slope test working condition scene including uphill and downhill is constructed, and the functional safety of the electronic parking brake system in a complex environment can be represented more comprehensively.

Description

Technical Field

[0001] One or more embodiments of this specification relate to intelligent connected vehicle testing technology, and in particular, to a functional safety evaluation method for an electronic parking brake system under longitudinal slope conditions. Background Art

[0002] The Electronic Park Brake (EPB) system is one of the core components of modern cars and even intelligent connected vehicles. It achieves parking braking through electronic control, integrating temporary braking during driving and long-term braking after parking. The stability and safety of its performance are crucial to ensuring driving safety.

[0003] In recent years, functional safety has gradually received widespread attention both at home and abroad. For electronic parking brake systems, it is necessary to ensure that vehicles avoid unreasonable risks caused by abnormal functional performance of the EPB electronic and electrical system. Therefore, how to accurately carry out EPB functional safety testing and scientifically and comprehensively evaluate its functional safety performance is of great significance for verifying the correctness and rationality of the electric power steering system design and ensuring the safe operation of the entire vehicle. However, the current functional safety tests for electronic parking brake systems have shortcomings such as simple test scenarios and relatively single evaluation indicators. In addition, there is no research on the functional safety performance evaluation of electronic parking brake systems under uphill and downhill conditions, making it difficult to reliably and comprehensively verify the functional safety of EPB. Summary of the Invention

[0004] In order to solve the above problems, one or more embodiments of this specification describe a functional safety evaluation method for an electronic parking brake system under longitudinal slope conditions.

[0005] According to a first aspect, a functional safety evaluation method for an electronic parking brake system under a longitudinal slope condition is provided, the method comprising:

[0006] Constructing a functional safety test case library for an electronic parking brake system on a longitudinal slope, wherein the components of the functional safety test case library include fault type, longitudinal slope type, slope, and fault injection timing;

[0007] Constructing a functional safety evaluation index for an electronic parking brake system, wherein the functional safety evaluation index includes at least two subjective evaluation indexes and at least two objective evaluation indexes;

[0008] Constructing a functional safety evaluation model for an electronic parking brake system, and processing the functional safety evaluation model based on the analytic hierarchy process to obtain weights of the functional safety evaluation indicators, wherein the functional safety evaluation model includes a target layer, a criterion layer, and a solution layer, wherein the target layer is defined as the top layer of the functional safety evaluation, the criterion layer is defined as the middle layer for subjective and objective evaluations, and the solution layer is the bottom layer including subjective and objective evaluation indicators;

[0009] Receive a test instruction, select constituent elements from the functional safety test case library to construct a test condition, determine a functional safety evaluation index score of the vehicle under test under the test condition, and weight each functional safety evaluation index score to obtain an evaluation result of the vehicle under test under the test condition.

[0010] Preferably, the fault types include electronic parking brake system short circuit, electronic parking brake system open circuit, electronic parking brake system motor failure and electronic parking brake system communication failure, the longitudinal slope types include uphill and downhill, and the fault injection timing includes before applying the parking brake, during applying the parking brake and after applying the parking brake.

[0011] Preferably, the subjective evaluation indicators include the display of the electronic parking brake system function fault light on the instrument panel after fault injection, the display of the electric power steering system fault light on the instrument panel after the engine is restarted after stopping the fault injection, the degree of deviation of the tested vehicle from the lane center line and the controllability of the tested vehicle; the objective evaluation indicators include the fault takeover time, the maximum pedal force meter value of the tested vehicle after fault injection, the maximum deceleration of the tested vehicle after fault injection and the maximum body yaw angle of the tested vehicle after fault injection.

[0012] Preferably, the processing of the functional safety evaluation model based on the analytic hierarchy process to obtain the weight of each functional safety evaluation indicator includes:

[0013] Starting from the bottom layer, compare the indicators at the same level in pairs, establish a comparative judgment matrix, and determine the weight of each indicator at the same level based on the comparative judgment matrix;

[0014] According to the definition classification, the weights of the indicators at the same level are integrated layer by layer to obtain the weights of the functional safety evaluation indicators.

[0015] Preferably, the pairwise comparison of the same-level indicators to establish a comparison judgment matrix, and determining the weight of each same-level indicator according to the comparison judgment matrix, includes:

[0016] Compare the indicators at the same level pairwise to obtain the comparison results;

[0017] Establishing a comparison judgment matrix based on each of the comparison results, and adjusting the comparison judgment matrix to obtain a target judgment matrix corresponding to the maximum eigenvalue of the matrix;

[0018] The weights of the indicators at the same level in the target judgment matrix are calculated based on the square root method.

[0019] Preferably, determining the functional safety evaluation index score of the tested vehicle under the test condition includes:

[0020] Acquiring actual driving data of the tested vehicle under the test conditions, and determining an objective evaluation index score based on the actual driving data;

[0021] Obtain the subjective evaluation index score sent by the test terminal corresponding to the tester of the tested vehicle.

[0022] Preferably, the method further comprises:

[0023] Record the evaluation results corresponding to the test conditions.

[0024] According to a second aspect, a functional safety evaluation device for an electronic parking brake system under a longitudinal slope condition is provided, the device comprising:

[0025] The first building module is used to build a functional safety test case library for the electronic parking brake system on a longitudinal slope road surface, wherein the components of the functional safety test case library include fault type, longitudinal slope type, slope, and fault injection timing;

[0026] A second building module is used to build a functional safety evaluation index of the electronic parking brake system, wherein the functional safety evaluation index includes at least two subjective evaluation indicators and at least two objective evaluation indicators;

[0027] a third construction module, configured to construct a functional safety evaluation model for the electronic parking brake system, and process the functional safety evaluation model based on a hierarchical analysis method to obtain weights of the functional safety evaluation indicators, wherein the functional safety evaluation model includes a target layer, a criterion layer, and a solution layer, wherein the target layer is defined as the top layer of the functional safety evaluation, the criterion layer is defined as the middle layer for subjective and objective evaluations, and the solution layer is the bottom layer including subjective and objective evaluation indicators;

[0028] An evaluation module is used to receive test instructions, select component elements from the functional safety test case library to construct a test condition, determine the functional safety evaluation index score of the vehicle under test under the test condition, and weight each functional safety evaluation index score to obtain an evaluation result of the vehicle under test under the test condition.

[0029] According to a third aspect, there is provided an electronic device comprising a processor and a memory;

[0030] The processor is connected to the memory;

[0031] The memory is used to store executable program code;

[0032] The processor runs a program corresponding to the executable program code by reading the executable program code stored in the memory, so as to execute the steps of the method provided in the first aspect or any possible implementation manner of the first aspect.

[0033] According to a fourth aspect, a computer-readable storage medium is provided, on which a computer program is stored, and the computer-readable storage medium stores instructions, which, when the instructions are executed on a computer or a processor, enable the computer or the processor to execute the method provided in the first aspect or any possible implementation of the first aspect.

[0034] Compared with the test scenario without slope, the method and device provided in the embodiments of this specification construct a longitudinal slope test scenario including uphill and downhill, which can more comprehensively characterize the functional safety of the electronic parking brake system in a complex environment. Compared with a single evaluation indicator, multiple functional safety evaluation indicators including subjective evaluation and objective quantitative evaluation are constructed, and the weight of each indicator is determined, thereby realizing a reliable, comprehensive and scientific quantitative evaluation of the functional safety of the electronic parking brake system. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0036] Figure 1 It is a flow chart of a functional safety evaluation method of an electronic parking brake system under a longitudinal slope condition in one embodiment of this specification.

[0037] Figure 2 This is a structural diagram of a functional safety evaluation device for an electronic parking brake system under a longitudinal slope condition in one embodiment of this specification.

[0038] Figure 3 It is a structural diagram of an electronic device in one embodiment of this specification. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application.

[0040] In the following introduction, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance. The following introduction provides multiple embodiments of the present application. Different embodiments can be replaced or combined, so the present application can also be considered to include all possible combinations of the same and / or different embodiments described. Therefore, if one embodiment includes features A, B, and C, and another embodiment includes features B and D, then the present application should also be considered to include embodiments containing one or more of all other possible combinations of A, B, C, and D, even though the embodiment may not be clearly described in the following text.

[0041] The following description provides examples and does not limit the scope, applicability, or examples set forth in the claims. Changes may be made to the function and arrangement of the elements described without departing from the scope of the present application. Various examples may appropriately omit, replace, or add various processes or components. For example, the described method may be performed in an order different from the order described, and various steps may be added, omitted, or combined. In addition, features described in some examples may be combined in other examples.

[0042] See also Figure 1 , Figure 1 This is a flow chart of a method for functional safety evaluation of an electronic parking brake system under longitudinal slope conditions provided in an embodiment of the present application. In this embodiment of the present application, the method includes:

[0043] S101. Build a functional safety test case library for the electronic parking brake system on a longitudinal slope road surface.

[0044] Among them, the constituent elements of the functional safety test case library include fault type, longitudinal slope type, slope and fault injection timing.

[0045] The execution entity of this application can be a cloud server.

[0046] In this embodiment, a single-lane uphill and downhill road in a closed test field is used as the test site. A functional safety test case library for the electronic parking brake system under unexpected longitudinal motion is established within this field. Elements of the functional safety test case library may include fault type, longitudinal slope type, slope, and the timing of fault injection.

[0047] In one embodiment, the fault types include electronic parking brake system short circuit, electronic parking brake system open circuit, electronic parking brake system motor fault and electronic parking brake system communication fault, the longitudinal slope types include uphill and downhill, and the fault injection timing includes before applying the parking brake, during applying the parking brake and after applying the parking brake.

[0048] In the embodiments of this specification, fault types may include an electronic parking brake system short circuit, an electronic parking brake system open circuit, an electronic parking brake system motor fault, and an electronic parking brake system communication fault. Slope types may include uphill and downhill. Slopes may include 6%, 8%, 10%, and 12%. Fault injection timing may include before, during, and after the parking brake is applied. The specific slope classifications may be adjusted to suit different needs and locations.

[0049] S102. Construct functional safety evaluation indicators for the electronic parking brake system.

[0050] The functional safety evaluation index includes at least two subjective evaluation indexes and at least two objective evaluation indexes.

[0051] In the embodiments of this specification, functional safety evaluation indicators are constructed to evaluate the functional safety performance of the electronic parking brake system. These indicators are divided into subjective and objective evaluation indicators, each of which includes at least two different indicator categories. For example, subjective evaluation indicators may include the display of the electronic parking brake system functional fault light on the instrument panel after fault injection, the display of the electric power steering system fault light on the instrument panel after the engine is restarted after the fault injection is stopped, etc. Objective evaluation indicators may include the maximum pedal force meter value of the tested vehicle after fault injection, the maximum deceleration of the tested vehicle after fault injection, etc.

[0052] In one embodiment, the subjective evaluation indicators include the display of the electronic parking brake system function fault light on the instrument panel after fault injection, the display of the electric power steering system fault light on the instrument panel after the engine is restarted after stopping the fault injection, the degree of deviation of the vehicle under test from the center line of the lane, and the controllability of the vehicle under test. The objective evaluation indicators include the fault takeover time, the maximum pedal force meter value of the vehicle under test after fault injection, the maximum deceleration of the vehicle under test after fault injection, and the maximum body yaw angle of the vehicle under test after fault injection.

[0053] In the embodiments of this specification, the subjective evaluation indicators may specifically include:

[0054] I1=[0,1]

[0055] Where I1 represents the display of the electronic parking brake system function fault light on the instrument panel after the fault is injected. I1=0 means the fault light is always on, and I1=1 means the fault light is not on.

[0056] I2=[0,1]

[0057] Where, I2 represents the status of the electric power steering system fault light on the instrument panel after the injection fault is stopped and the engine is restarted. I2=0 means the fault light is off, and I2=1 means the fault light is always on.

[0058] I3=[0,1,2]

[0059] Where I3 represents the degree to which the measured vehicle deviates from the lane centerline. I3=0 indicates that the measured vehicle does not deviate from the lane centerline. I3=1 indicates that the measured vehicle deviates from the lane centerline but the degree of deviation is low. I3=2 indicates that the measured vehicle deviates from the lane centerline and the degree of deviation is high.

[0060] I4=[0,1,2]

[0061] Where I4 represents the controllability of the vehicle under test. I4=0 means no change in controllability. I4=1 means the hand force changes but the vehicle under test is controllable. I4=2 means the pedal suddenly changes and the vehicle becomes uncontrollable.

[0062] Objective evaluation indicators include:

[0063] I5=T c -T l

[0064] Where, I5 represents the fault takeover time in milliseconds, T c represents the fault injection time, T l Indicates the time when the instrument fault light signal is on.

[0065] In addition, objective evaluation indicators also include: the maximum pedal force meter value of the tested vehicle after fault injection I6, the maximum deceleration of the tested vehicle after fault injection I7, and the maximum body yaw angle of the tested vehicle after fault injection I8.

[0066] S103: Construct a functional safety evaluation model for the electronic parking brake system, and process the functional safety evaluation model based on the analytic hierarchy process to obtain the weight of each functional safety evaluation indicator.

[0067] Among them, the functional safety evaluation model includes a target layer, a criterion layer and a solution layer. The target layer is defined as the top layer of functional safety evaluation, the criterion layer is defined as the middle layer of subjective evaluation and objective evaluation, and the solution layer is the bottom layer including subjective evaluation indicators and objective evaluation indicators.

[0068] In the embodiments of this specification, a functional safety evaluation model for an electronic parking brake system is also constructed. This model consists of three layers: the target layer, as the top layer in the hierarchy, is defined as the functional safety evaluation of the electronic parking brake system. The criterion layer, as the middle layer in the hierarchy, is defined as subjective evaluation and objective evaluation. The solution layer is the bottom layer in the hierarchy. The solution layer corresponding to the "subjective evaluation" includes subjective evaluation indicators I1, I2, I3, and I4, and the solution layer corresponding to the "objective evaluation" includes objective evaluation indicators I5, I6, I7, and I8. Next, the cloud server will process the functional safety evaluation model using the Analytic Hierarchy Process (AHP). The Analytic Hierarchy Process (AHP) is a multi-criteria decision analysis method. The basic principle of AHP is to decompose a complex problem into an ordered hierarchical structure and determine the importance weights of each element through pairwise comparison. These weights are then used to comprehensively evaluate the value of alternative solutions to support the final decision. Through the hierarchical analysis method, we can first determine the weights of the indicators at the bottom level, and then use this to calculate the combined weights of the indicators at the next level. Then, we can calculate the weights layer by layer from the bottom level upwards until we reach the decision-making target layer and obtain the weights of the functional safety evaluation indicators.

[0069] In one possible implementation, processing the functional safety evaluation model based on the analytic hierarchy process to obtain the weight of each functional safety evaluation indicator includes:

[0070] Starting from the bottom layer, compare the indicators at the same level in pairs, establish a comparative judgment matrix, and determine the weight of each indicator at the same level based on the comparative judgment matrix;

[0071] According to the definition classification, the weights of the indicators at the same level are integrated layer by layer to obtain the weights of the functional safety evaluation indicators.

[0072] In the embodiments of this specification, starting from the bottom layer, the indicators at the same level are compared pairwise, and a comparison judgment matrix is ​​constructed based on the comparison results. Among them, the pairwise comparison method can be to manually compare and then score based on experience, or to pre-set corresponding scores for each level indicator and directly calculate the ratio of the two. After obtaining the comparison judgment matrix, the weight of each indicator in the comparison judgment matrix will be calculated according to the square root method. Then, according to the categories of the level indicators in the hierarchy, the weights of each level are determined and integrated step by step, and finally the weight of the functional safety evaluation indicator at the top level is obtained.

[0073] In one possible implementation, the pairwise comparison of the same-level indicators to establish a comparison judgment matrix, and determining the weight of each same-level indicator according to the comparison judgment matrix, includes:

[0074] Compare the indicators at the same level pairwise to obtain the comparison results;

[0075] Establishing a comparison judgment matrix based on each of the comparison results, and adjusting the comparison judgment matrix to obtain a target judgment matrix corresponding to the maximum eigenvalue of the matrix;

[0076] The weights of the indicators at the same level in the target judgment matrix are calculated based on the square root method.

[0077] In the embodiments of this specification, a 1-9 scale method is used to determine the importance of each indicator at the same level. A scale value of 1 indicates that the two elements are of equal importance. A scale value of 3 indicates that the former is slightly more important than the latter when compared with the two elements. A scale value of 5 indicates that the former is significantly more important than the latter when compared with the two elements. A scale value of 7 indicates that the former is strongly more important than the latter when compared with the two elements. A scale value of 9 indicates that the former is particularly important than the latter when compared with the two elements. Scale values ​​of 2, 4, 6, and 8 represent the intermediate values ​​of the above-mentioned adjacent judgments. The cloud server compares the indicators at the same level pairwise, and then scales each comparison result by comparing the numerical range of the comparison results, or by manually judging the comparison results. Suppose that the evaluation indicator set I of n evaluation indicators is I = {I1, I2, I3, ..., I n}, two factors are compared in pairs, that is After comparing and determining the scale, establish the comparison judgment matrix A according to the matrix scale:

[0078] A=a ij

[0079]

[0080] Depending on the comparison object, the position of the matrix elements can be adjusted, which will cause the matrix eigenvalue to change. The solution with the largest matrix eigenvalue is the optimal solution. Therefore, first calculate the largest eigenvalue of matrix A:

[0081]

[0082] Where λ max Represents the maximum eigenvalue of the comparison judgment matrix, W i represents the i-th eigenvector,

[0083] Next, the square root method is used to calculate the index weight value, that is, to calculate the product M of each row element of the judgment matrix A. i The eigenvector of the nth root value of Where n represents the matrix order, that is, the number of evaluation indicators in the evaluation indicator set.

[0084] Normalize the eigenvectors:

[0085]

[0086] Where, ω i is the weight of the required level indicator.

[0087] S104: Receive a test instruction, select constituent elements from the functional safety test case library to construct a test condition, determine a functional safety evaluation index score of the vehicle under test under the test condition, and weight each functional safety evaluation index score to obtain an evaluation result of the vehicle under test under the test condition.

[0088] In the embodiments of this specification, after receiving a test instruction, the cloud server selects various types of components from the functional safety test case library according to the test instruction, constructs a test condition, performs system control on the vehicle under test according to the test condition, and determines the functional safety evaluation index score of the vehicle under test during the control process. Finally, the functional safety evaluation index scores are weighted according to the weights of the previous steps to obtain the evaluation results of the vehicle under test under the test condition. The functional safety evaluation index scores are divided into subjective evaluation index scores and objective evaluation index scores. The former can be assessed by the test personnel of the vehicle under test, and the latter can be determined based on the vehicle's driving data.

[0089] As an example, the test process of the vehicle under test under the test conditions may be:

[0090] Sub-step 1: Select the longitudinal slope type and slope for this test;

[0091] Sub-step 2: Stop the fully loaded vehicle under test on the corresponding test road surface;

[0092] Sub-step 3: Select the fault type and timing of fault injection for this test;

[0093] Sub-step 4: Based on the selected timing of fault injection, inject the fault into the electronic parking brake system of the vehicle under test before, during, or after the parking brake is applied. The fault injection time is 3000ms.

[0094] Sub-step 5: Based on the performance of the tested vehicle after the fault injection, the tester gives a subjective score;

[0095] Sub-step 6: Use a pedal force meter to measure and record the pedal force value after the fault injection;

[0096] Sub-step 7: Using a high-precision dual-antenna integrated navigation system, measure and record the change in deceleration of the vehicle under test after the fault is injected;

[0097] Sub-step 8: Use the data acquisition system to measure and record the fault takeover time;

[0098] Sub-step 9: Using a high-precision dual-antenna integrated navigation system, measure and record the change in the yaw angle of the vehicle under test after the fault is injected.

[0099] Sub-step 10: After the fault injection disappears, the tester restarts the engine and observes whether the instrument fault light disappears.

[0100] In one embodiment, determining the functional safety evaluation index score of the tested vehicle under the test condition includes:

[0101] Acquiring actual driving data of the tested vehicle under the test conditions, and determining an objective evaluation index score based on the actual driving data;

[0102] Obtain the subjective evaluation index score sent by the test terminal corresponding to the tester of the tested vehicle.

[0103] In the embodiments of this specification, the cloud server will obtain the actual driving data of the tested vehicle under test conditions to calculate the objective evaluation index score. Simultaneously, the tester corresponding to the vehicle will also select a score for each subjective evaluation index using the test terminal used during the test. The cloud server can directly obtain the subjective evaluation index score through the test terminal.

[0104] In one embodiment, the method further comprises:

[0105] Record the evaluation results corresponding to the test conditions.

[0106] In the embodiment of this specification, the cloud server will also automatically record the evaluation results of the test conditions, rather than simply displaying them. In this way, as different test conditions are tested, the evaluation results corresponding to all test conditions can be recorded, which is convenient for staff to compare and analyze.

[0107] The following will be combined with the Figure 2 , the functional safety evaluation device of the electronic parking brake system under the longitudinal slope condition provided by the embodiment of the present application is introduced in detail. Figure 2 The functional safety evaluation device of the electronic parking brake system under the longitudinal slope condition shown is used to perform the application Figure 1 For the convenience of explanation, only the part related to the embodiment of the present application is shown. For the specific technical details not disclosed, please refer to the present application. Figure 1 The embodiment shown.

[0108] See Figure 2 , Figure 2 This is a schematic diagram of the structure of a functional safety evaluation device for an electronic parking brake system under longitudinal slope conditions provided by an embodiment of the present application. Figure 2As shown, the device includes:

[0109] The first building module 201 is used to build a functional safety test case library for the electronic parking brake system on a longitudinal slope road surface, wherein the components of the functional safety test case library include fault type, longitudinal slope type, slope, and fault injection timing;

[0110] A second building module 202 is used to build a functional safety evaluation index of the electronic parking brake system, wherein the functional safety evaluation index includes at least two subjective evaluation indexes and at least two objective evaluation indexes;

[0111] The third construction module 203 is configured to construct a functional safety evaluation model for the electronic parking brake system, and process the functional safety evaluation model based on the analytic hierarchy process to obtain weights of the functional safety evaluation indicators. The functional safety evaluation model includes a target layer, a criterion layer, and a solution layer. The target layer is defined as the top layer of the functional safety evaluation, the criterion layer is defined as the middle layer for subjective and objective evaluations, and the solution layer is the bottom layer including subjective and objective evaluation indicators.

[0112] The evaluation module 204 is used to receive test instructions, select component elements from the functional safety test case library to construct a test condition, determine the functional safety evaluation index score of the vehicle under test under the test condition, and weight each functional safety evaluation index score to obtain an evaluation result of the vehicle under test under the test condition.

[0113] In one embodiment, the fault types include electronic parking brake system short circuit, electronic parking brake system open circuit, electronic parking brake system motor fault and electronic parking brake system communication fault, the longitudinal slope types include uphill and downhill, and the fault injection timing includes before applying the parking brake, during applying the parking brake and after applying the parking brake.

[0114] In one embodiment, the subjective evaluation indicators include the display of the electronic parking brake system function fault light on the instrument panel after fault injection, the display of the electric power steering system fault light on the instrument panel after the engine is restarted after stopping the fault injection, the degree of deviation of the vehicle under test from the center line of the lane, and the controllability of the vehicle under test. The objective evaluation indicators include the fault takeover time, the maximum pedal force meter value of the vehicle under test after fault injection, the maximum deceleration of the vehicle under test after fault injection, and the maximum body yaw angle of the vehicle under test after fault injection.

[0115] In one embodiment, the third building module 203 is specifically configured to:

[0116] Starting from the bottom layer, compare the indicators at the same level in pairs, establish a comparative judgment matrix, and determine the weight of each indicator at the same level based on the comparative judgment matrix;

[0117] According to the definition classification, the weights of the indicators at the same level are integrated layer by layer to obtain the weights of the functional safety evaluation indicators.

[0118] In one embodiment, the third building module 203 is further configured to:

[0119] Compare the indicators at the same level pairwise to obtain the comparison results;

[0120] Establishing a comparison judgment matrix based on each of the comparison results, and adjusting the comparison judgment matrix to obtain a target judgment matrix corresponding to the maximum eigenvalue of the matrix;

[0121] The weights of the indicators at the same level in the target judgment matrix are calculated based on the square root method.

[0122] In one embodiment, the evaluation module 204 is specifically configured to:

[0123] Acquiring actual driving data of the tested vehicle under the test conditions, and determining an objective evaluation index score based on the actual driving data;

[0124] Obtain the subjective evaluation index score sent by the test terminal corresponding to the tester of the tested vehicle.

[0125] In one embodiment, the device further comprises:

[0126] The recording module is used to record the evaluation results corresponding to the test conditions.

[0127] Those skilled in the art will clearly understand that the technical solutions of the embodiments of the present application can be implemented with the help of software and / or hardware. "Unit" and "module" in this specification refer to software and / or hardware that can independently perform or cooperate with other components to perform specific functions, where the hardware can be, for example, a field programmable gate array (FPGA), an integrated circuit (IC), etc.

[0128] Each processing unit and / or module in the embodiments of the present application may be implemented by an analog circuit that implements the functions described in the embodiments of the present application, or may be implemented by software that executes the functions described in the embodiments of the present application.

[0129] See also Figure 3 , which shows a schematic diagram of the structure of an electronic device involved in an embodiment of the present application, the electronic device can be used to implement Figure 1 The method in the embodiment shown. Figure 3 As shown, the electronic device 300 may include: at least one processor 301 , at least one network interface 304 , a user interface 303 , a memory 305 , and at least one communication bus 302 .

[0130] The communication bus 302 is used to implement the connection and communication between these components.

[0131] The user interface 303 may include a display screen (Display) and a camera (Camera). Optionally, the user interface 303 may also include a standard wired interface and a wireless interface.

[0132] The network interface 304 may optionally include a standard wired interface or a wireless interface (such as a WI-FI interface).

[0133] The processor 301 may include one or more processing cores. The processor 301 utilizes various interfaces and circuits to connect the various components within the entire electronic device 300. It executes various functions and processes data for the electronic device 300 by running or executing instructions, programs, code sets, or instruction sets stored in the memory 305, as well as accessing data stored in the memory 305. Optionally, the processor 301 may be implemented using at least one hardware form of a digital signal processing (DSP), a field-programmable gate array (FPGA), or a programmable logic array (PLA). The processor 301 may integrate one or a combination of a central processing unit (CPU), a graphics processing unit (GPU), and a modem. The CPU primarily processes the operating system, user interface, and application programs; the GPU is responsible for rendering and drawing the content to be displayed on the display; and the modem handles wireless communications. It is understood that the modem may not be integrated into the processor 301 and may be implemented separately on a single chip.

[0134] Among them, the memory 305 may include a random access memory (RAM) or a read-only memory (Read-Only Memory). Optionally, the memory 305 includes a non-transitory computer-readable storage medium. The memory 305 can be used to store instructions, programs, codes, code sets or instruction sets. The memory 305 may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for at least one function (such as a touch function, a sound playback function, an image playback function, etc.), instructions for implementing the above-mentioned various method embodiments, etc.; the data storage area may store data involved in the above-mentioned various method embodiments, etc. The memory 305 may also be optionally at least one storage device located away from the aforementioned processor 301. As Figure 3 As shown, the memory 305 as a computer storage medium may include an operating system, a network communication module, a user interface module, and program instructions.

[0135] exist Figure 3 In the electronic device 300 shown, the user interface 303 is primarily used to provide an input interface for the user and obtain user input data; and the processor 301 can be used to call the electronic parking brake system functional safety assessment application under longitudinal slope conditions stored in the memory 305 and specifically perform the following operations:

[0136] Constructing a functional safety test case library for an electronic parking brake system on a longitudinal slope, wherein the components of the functional safety test case library include fault type, longitudinal slope type, slope, and fault injection timing;

[0137] Constructing a functional safety evaluation index for an electronic parking brake system, wherein the functional safety evaluation index includes at least two subjective evaluation indexes and at least two objective evaluation indexes;

[0138] Constructing a functional safety evaluation model for an electronic parking brake system, and processing the functional safety evaluation model based on the analytic hierarchy process to obtain weights of the functional safety evaluation indicators, wherein the functional safety evaluation model includes a target layer, a criterion layer, and a solution layer, wherein the target layer is defined as the top layer of the functional safety evaluation, the criterion layer is defined as the middle layer for subjective and objective evaluations, and the solution layer is the bottom layer including subjective and objective evaluation indicators;

[0139] Receive a test instruction, select constituent elements from the functional safety test case library to construct a test condition, determine a functional safety evaluation index score of the vehicle under test under the test condition, and weight each functional safety evaluation index score to obtain an evaluation result of the vehicle under test under the test condition.

[0140] The present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above method. The computer-readable storage medium may include, but is not limited to, any type of disk, including a floppy disk, an optical disk, a DVD, a CD-ROM, a microdrive, a magneto-optical disk, a ROM, a RAM, an EPROM, an EEPROM, a DRAM, a VRAM, a flash memory device, a magnetic card or an optical card, a nanosystem (including a molecular memory IC), or any type of medium or device suitable for storing instructions and / or data.

[0141] It should be noted that for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that this application is not limited by the order of the actions described, because according to this application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by this application.

[0142] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0143] In the several embodiments provided in this application, it should be understood that the disclosed devices can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some service interface, and the indirect coupling or communication connection of the device or unit can be electrical or other forms.

[0144] The units described as separate components may or may not be physically separate, and 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 these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0145] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0146] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable memory. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a memory, including a number of instructions for enabling a computer device (which can be a personal computer, server or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned memory includes: various media that can store program codes, such as a USB flash drive, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk or an optical disk.

[0147] Those skilled in the art will appreciate that all or part of the steps in the various methods of the above embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable memory, which may include: a flash drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc.

[0148] The above is only an exemplary embodiment of the present disclosure and cannot be used to limit the scope of the present disclosure. That is, any equivalent changes and modifications made according to the teachings of the present disclosure are still within the scope of the present disclosure. After considering the specification and practicing the disclosure herein, those skilled in the art will easily think of the implementation scheme of the present disclosure. This application is intended to cover any variation, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary technical means in the art that are not recorded in the present disclosure. The description and examples are to be regarded as exemplary only, and the scope and spirit of the present disclosure are defined by the claims.

Claims

1. A functional safety evaluation method for an electronic parking brake system under longitudinal slope conditions, characterized in that: The method comprises: Constructing a functional safety test case library of an electronic parking brake system on a longitudinal slope road surface, wherein the components of the functional safety test case library include fault type, longitudinal slope type, slope, and fault injection timing; Constructing a functional safety evaluation index for an electronic parking brake system, wherein the functional safety evaluation index includes at least two subjective evaluation indexes and at least two objective evaluation indexes; Constructing a functional safety evaluation model for an electronic parking brake system, and processing the functional safety evaluation model based on a hierarchical analysis method to obtain weights of each functional safety evaluation index, wherein the functional safety evaluation model includes a target layer, a criterion layer, and a solution layer, wherein the target layer is defined as the top layer of the functional safety evaluation, the criterion layer is defined as the middle layer of subjective evaluation and objective evaluation, and the solution layer is the bottom layer including subjective evaluation indicators and objective evaluation indicators; Receive a test instruction, select constituent elements from the functional safety test case library to construct a test condition, determine a functional safety evaluation index score of the vehicle under test under the test condition, and weight each of the functional safety evaluation index scores to obtain an evaluation result of the vehicle under test under the test condition.

2. The method according to claim 1, characterized in that The fault types include electronic parking brake system short circuit, electronic parking brake system open circuit, electronic parking brake system motor fault and electronic parking brake system communication fault. The longitudinal slope types include uphill and downhill. The fault injection timing includes before applying the parking brake, during applying the parking brake and after applying the parking brake.

3. The method according to claim 1, characterized in that: The subjective evaluation indicators include the display of the electronic parking brake system function fault light on the instrument panel after fault injection, the display of the electric power steering system fault light on the instrument panel after the engine is restarted after stopping the fault injection, the degree of deviation of the vehicle under test from the center line of the lane and the controllability of the vehicle under test. The objective evaluation indicators include the fault takeover time, the maximum pedal force meter value of the vehicle under test after fault injection, the maximum deceleration of the vehicle under test after fault injection and the maximum body yaw angle of the vehicle under test after fault injection.

4. The method according to claim 1, characterized in that: The step of processing the functional safety evaluation model based on the hierarchical analysis method to obtain the weight of each functional safety evaluation index includes: Starting from the bottom layer, compare the indicators at the same level in pairs, establish a comparison judgment matrix, and determine the weight of each indicator at the same level according to the comparison judgment matrix; According to the defined classification, the weights of the indicators at the same level are integrated layer by layer to obtain the weights of the functional safety evaluation indicators.

5. The method according to claim 4, characterized in that The pairwise comparison of the same-level indicators to establish a comparison judgment matrix, and determining the weight of each same-level indicator according to the comparison judgment matrix, includes: Compare the indicators at the same level pairwise to obtain the comparison results; Establishing a comparison judgment matrix based on each of the comparison results, and adjusting the comparison judgment matrix to obtain a target judgment matrix corresponding to the maximum eigenvalue of the matrix; The weights of the indicators at the same level in the target judgment matrix are calculated based on the square root method.

6. The method according to claim 1, characterized in that Determining the functional safety evaluation index score of the tested vehicle under the test condition includes: Acquiring actual driving data of the tested vehicle under the test conditions, and determining an objective evaluation index score based on the actual driving data; Obtain the subjective evaluation index score sent by the test terminal corresponding to the tester of the tested vehicle.

7. The method according to claim 1, characterized in that The method further comprises: Record the evaluation results corresponding to the test conditions.

8. A functional safety evaluation device for an electronic parking brake system under longitudinal slope conditions, characterized in that: The device comprises: The first building module is used to build a functional safety test case library of the electronic parking brake system on a longitudinal slope road surface, wherein the constituent elements of the functional safety test case library include fault type, longitudinal slope type, slope and fault injection timing; A second building module is used to build a functional safety evaluation index of the electronic parking brake system, wherein the functional safety evaluation index includes at least two subjective evaluation indexes and at least two objective evaluation indexes; A third construction module is used to construct a functional safety evaluation model of the electronic parking brake system, and process the functional safety evaluation model based on the hierarchical analysis method to obtain the weight of each functional safety evaluation index, wherein the functional safety evaluation model includes a target layer, a criterion layer and a scheme layer, wherein the target layer is defined as the top layer of the functional safety evaluation, the criterion layer is defined as the middle layer of subjective evaluation and objective evaluation, and the scheme layer is the bottom layer including subjective evaluation indicators and objective evaluation indicators; The evaluation module is used to receive test instructions, select component elements from the functional safety test case library to construct test conditions, determine the functional safety evaluation index score of the tested vehicle under the test conditions, and weight each functional safety evaluation index score to obtain an evaluation result of the tested vehicle under the test conditions.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, wherein the computer-readable storage medium has instructions stored therein, and when the instructions are executed on a computer or a processor, the computer or the processor executes the steps of the method according to any one of claims 1 to 7.

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