A method and system for testing a differential lock controller function

Abstract

The application discloses a kind of differential lock controller function test method and system, method includes according to test working condition input condition, obtains differential lock switch signal, differential lock switch signal is input differential lock controller, differential lock controller runs, obtains response signal, response signal is input simulation model by simulation device, according to test working condition input condition and response signal, drive simulation model work, obtain differential lock feedback switch simulation state;Differential lock feedback switch simulation state is input differential lock controller by simulation device, differential lock controller runs, obtains actual result;Actual result and expected result are compared, and the function of differential lock controller is tested;Expected result is according to test working condition input condition, and expected differential lock controller runs output result.This embodiment realizes the physical software function test of differential lock controller under multiple working conditions before loading, reduces real vehicle debugging rectification period.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of vehicle testing, in particular to a method and system for testing the function of a differential lock controller. BACKGROUND

[0002] At present, most trucks are equipped with rear axle differential lock and rear axle differential lock, and in the development process of the differential lock system, the software function logic of the differential lock controller can only be tested at the software level during development, and the physical function test can only rely on the real vehicle. At the same time, the differential lock function is closely related to the power chassis of the real vehicle, and can only be carried out after being installed and running normally, involving the development and installation of various systems related to vehicle operation.

[0003] However, the physical function test of the differential lock controller cannot be safely and conveniently carried out in the real vehicle environment under various working conditions, such as opening the differential lock at high speed, opening the differential lock when turning, and other dangerous working condition tests, as well as differential lock switch short circuit, electromagnetic valve short circuit and other fault tests. In addition, during the development process of a new vehicle model, the development and installation progress of multiple systems of the whole vehicle has a great influence on the progress of the differential lock controller function test. SUMMARY

[0004] The present application provides a method and system for testing the function of a differential lock controller, which can test the physical software function of the differential lock controller under various working conditions before installation, and is not affected by the development and installation progress of the whole vehicle, reducing the debugging and modification period of the real vehicle.

[0005] In order to solve the above technical problems, the present application provides a method for testing the function of a differential lock controller, comprising:

[0006] According to the test condition input condition, the differential lock switch signal is obtained, the differential lock switch signal is input into the differential lock controller, so that the differential lock controller runs, and the response signal is obtained; wherein the test condition input condition includes opening the differential lock at high speed, opening the differential lock when turning, differential lock switch short circuit and electromagnetic valve short circuit;

[0007] The response signal is input into the simulation model through the simulation device, the simulation model is driven to work according to the test condition input condition and the response signal, and the differential lock feedback switch simulation state is obtained;

[0008] The differential lock feedback switch simulation state is input into the differential lock controller through the simulation device, so that the differential lock controller runs, and the actual result is obtained; wherein the actual result includes differential lock control output voltage and fault prompt;

[0009] The actual result and the expected result are compared, and the function of the differential lock controller is tested; wherein the expected result is the expected output result of the differential lock controller according to the test condition input condition.

[0010] According to the differential lock switch signal of the test working condition or use case input condition, the differential lock switch signal is input as an input signal of the differential lock controller to be tested, the differential lock controller outputs a response signal after running according to its own function logic, the response signal is input into the simulation model through the simulation device according to the test working condition input condition and the response signal, the simulation model is driven to work according to the test working condition input condition and the response signal, the differential lock feedback switch simulation state of the simulation model running is output, the differential lock feedback switch simulation state is input into the differential lock controller through the simulation device, the differential lock controller runs according to its own function logic, and the differential lock control output voltage and fault prompt are fed back and output. The actual result is compared with the expected result of the test working condition input condition, the function of the differential lock controller is tested, whether the differential lock controller is normal is judged, the real vehicle environment is simulated by the simulation device and the simulation model, the software function of the differential lock controller can be tested before being installed on the vehicle, the whole vehicle development and installation progress are not affected, the real vehicle debugging and rectification period is reduced. According to different test working conditions or use cases, different test working condition input conditions are provided, the simulation model can simulate multiple running conditions to provide the required input signals of the differential lock controller, the differential lock controller runs according to the input signals according to its own function logic, and the actual running result is output. The software function of the differential lock controller in different working conditions is tested, and the safety of the test process and the coverage of the function test are improved.

[0011] As a preferred solution, according to the test working condition input condition, the differential lock switch signal is obtained, and the differential lock switch signal is input into the differential lock controller, so that the differential lock controller runs and obtains a response signal. Specifically,

[0012] According to the test working condition input condition, a start test operation is performed in the upper device;

[0013] According to the variable association relationship and the start test operation of the upper device and the simulation model, the model variable parameters of the simulation model are controlled, and a differential lock switch variable is obtained.

[0014] The differential lock switch variable is input into the simulation device, the simulation device performs numerical voltage conversion, and outputs and obtains a differential lock switch signal;

[0015] The differential lock switch signal is input into the differential lock controller, so that the differential lock controller runs and outputs and obtains a response signal.

[0016] The embodiment of the present application is implemented, according to the test working condition input condition, to perform a test operation in the upper device, according to the variable association relationship between the upper device and the simulation model and the test operation, to perform parameter control of the simulation model, to perform the test of the differential lock controller without relying on the real vehicle by using the simulation model and the upper device, to ensure the safety of the test process, and to facilitate the fault test under various working conditions.

[0017] As a preferred solution, the response signal is input into the simulation model through the simulation device, the simulation model is driven to work according to the test working condition input condition and the response signal, and the differential lock feedback switch simulation state is obtained, specifically as follows:

[0018] The response signal is input into the simulation model through the simulation device, the response signal is input into the simulation device, the simulation device performs numerical voltage conversion, and the response variable is output and obtained;

[0019] According to the test working condition input condition, the numerical state of the simulation model is set;

[0020] The response variable is input into the simulation model, and the simulation model is driven to work, and the differential lock feedback switch simulation state is obtained; wherein the differential lock feedback switch simulation state includes the inter-axle differential lock feedback switch simulation state and the inter-wheel differential lock feedback switch simulation state.

[0021] The embodiment of the present application is implemented, according to different test working condition input conditions, to change the simulation model state and drive the simulation model to work, and to obtain the simulation result corresponding to the working condition, so as to facilitate the differential lock controller driven by the simulation working condition result as input, and to test the software function of the differential lock controller under various working conditions.

[0022] As a preferred solution, according to the test working condition input condition, the numerical state of the simulation model is set, specifically as follows:

[0023] When the test working condition input condition is the high-speed differential lock working condition, the turning differential lock working condition, the differential lock switch short circuit, or the electromagnetic valve short circuit;

[0024] The speed message of the virtual engine controller model is set to a preset first numerical value;

[0025] The speed message of the virtual instrument controller model sent to the differential lock controller is set to a preset second numerical value;

[0026] The differential lock switch of the differential lock switch model is set to be closed, wherein the differential lock switch includes the inter-axle differential lock switch and the inter-wheel differential lock switch.

[0027] The embodiment of the present application is implemented to detect that the differential lock controller controls the differential lock only when the engine starts, i.e., the speed is greater than a certain value, the virtual engine controller model provides the speed meeting the condition, the necessary condition for detecting the differential lock controller lock is provided, and the turning state can be judged through the speed difference between the left and right wheels to meet the test requirement of the working condition when the differential lock needs to be exited. The virtual instrument controller model provides the speed value, the necessary vehicle speed for providing the differential lock controller lock is provided, and the differential lock working condition at high speed can be detected.

[0028] As a preferred solution, the numerical state of the simulation model is set according to the test working condition input condition, specifically:

[0029] When the test working condition input condition is that the differential lock switch is short-circuited, a short circuit is formed between the input pin of the differential lock switch model and the input power supply;

[0030] When the test working condition input condition is that the electromagnetic valve is short-circuited, a short circuit is formed between the pin of the differential lock controller and the input power supply.

[0031] The embodiment of the present application is implemented to simulate the short-circuit state effectively and truly, which is a fault test that cannot be carried out in real vehicle testing, and improves the coverage of the test working condition.

[0032] As a preferred solution, the response variable is input into the simulation model and drives the simulation model to work to obtain the differential lock feedback switch simulation state, wherein the simulation model includes a virtual controller model, a differential lock switch model and a differential lock load model;

[0033] The virtual controller model includes a virtual engine controller model, a virtual instrument controller model and a virtual brake controller model;

[0034] The virtual engine controller model is used to simulate the engine controller sending the engine speed message to the differential lock controller;

[0035] The virtual instrument controller model is used to simulate the instrument system sending the vehicle speed message to the differential lock controller;

[0036] The virtual brake controller model is used to simulate the brake controller sending the steering axle wheel speed to the differential lock controller;

[0037] The differential lock switch model is used to simulate the inter-wheel differential lock switch and the inter-axle differential lock switch, and outputs the inter-axle differential lock feedback switch simulation state and the inter-wheel differential lock feedback switch simulation state;

[0038] The differential lock load model includes an inter-wheel differential lock working model and an inter-axle differential lock working model;

[0039] The inter-wheel differential lock working model is used for corresponding relationship between output voltage of the inter-wheel differential lock controlled by the differential lock controller and working state, and is associated with the inter-wheel differential lock feedback switch state;

[0040] The inter-axle differential lock working model is used for corresponding relationship between output voltage of the inter-axle differential lock controlled by the differential lock controller and working state, and is associated with the inter-axle differential lock feedback switch state.

[0041] The embodiment of the present application builds the inter-wheel and inter-axle differential lock working models, which are respectively associated with the inter-wheel and inter-axle differential lock feedback switch states, ensures that the electrical appliance logic is consistent with the actual vehicle state, and improves the accuracy of the test.

[0042] As a preferred scheme, the actual result and the expected result are compared, and the function of the differential lock controller is tested, specifically:

[0043] In the upper device, whether the differential lock controller controls the inter-wheel differential lock working model and the inter-axle differential lock working model to work according to the test working condition input condition is observed, and whether the actual result of the differential lock controller running is the same as the expected result is viewed, so as to test whether the software function of the differential lock controller is normal;

[0044] The expected result is the expected differential lock controller running output result according to the test working condition input condition.

[0045] In the embodiment of the present application, the differential lock controller software is designed according to the function specification (controller software function logic description file), and the consistency of the actual result and the expected result is compared, so as to accurately judge whether the software function of the differential lock controller is normal and whether it is designed according to the function specification.

[0046] As a preferred scheme, the response signal is input into the simulation model through the simulation device, the simulation model is driven to work according to the test working condition input condition and the response signal, and the differential lock feedback switch simulation state is obtained, wherein the simulation device includes an I / O board card module, a bus simulation board card module, a program-controlled power supply module and a real-time processor module;

[0047] The I / O board card module is used for simulating output of the electrical signal required by the differential lock controller, receiving the output electrical signal of the differential lock controller, and converting the output electrical signal into variable data for identification of the simulation model;

[0048] The bus simulation board module is used for providing a physical interface between the communication bus of the differential lock controller and the simulation model, converting the variable of the simulation model into a differential pressure signal for identification of the differential lock controller, and converting the differential pressure signal sent by the differential lock controller into variable data for identification of the simulation model;

[0049] The program-controlled power supply module is used for providing power supply for conversion of the output electrical signal of the I / O board card module.

[0050] The real-time processor module is used for core control of the simulation device, and coordinates and controls the modules.

[0051] The simulation device is used as a bridge between the simulation model and the differential lock controller, and converts the electrical signals required by the differential lock controller and the variables required by the simulation model, so that the simulation model and the differential lock controller can effectively identify corresponding data and perform responsive control actions.

[0052] To solve the same technical problem, the embodiment of the application also provides a test system for differential lock controller functions, which comprises a hardware-in-the-loop simulation device and a differential lock controller, and the hardware-in-the-loop simulation device performs a test method for differential lock controller functions.

[0053] The hardware-in-the-loop simulation device comprises a simulation model, a simulation device and an upper device.

[0054] The differential lock controller is connected to one end of the simulation device, the other end of the simulation device is connected to one end of the simulation model, and the other end of the simulation model is connected to the upper device. DETAILED DESCRIPTION

[0055] Figure 1 Fig. 1 is a flowchart of an embodiment of the test method for differential lock controller functions provided by the application;

[0056] Figure 2 Fig. 2 is a simulation model diagram of an embodiment of the test method for differential lock controller functions provided by the application;

[0057] Figure 3 Fig. 3 is a differential lock controller load peripheral wiring schematic diagram of an embodiment of the test method for differential lock controller functions provided by the application;

[0058] Figure 4 Fig. 4 is a structural schematic diagram of an embodiment of the test system for differential lock controller functions provided by the application;

[0059] Figure 5 Fig. 5 is a connection schematic diagram of an embodiment of the test system for differential lock controller functions provided by the application. DETAILED DESCRIPTION

[0060] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to 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 of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the application.

[0061] Embodiment one

[0062] Please refer to Figure 1 , a flowchart of a test method for differential lock controller function is provided in the embodiment of the application. The test method of the embodiment can be applied to the physical software function test of the differential lock controller under various working conditions before loading. The embodiment simulates the real vehicle environment by providing different test working condition input conditions, is not affected by the development of the whole vehicle and the loading progress, and improves the safety of the test process. The test method comprises steps 101 to 104, and each step is specifically as follows:

[0063] Step 101: According to the test working condition input condition, the differential lock switch signal is obtained, the differential lock switch signal is input into the differential lock controller, so that the differential lock controller runs, and a response signal is obtained; wherein the test working condition input condition comprises a high-speed differential lock opening working condition, a turning differential lock opening working condition, a differential lock switch short circuit and an electromagnetic valve short circuit.

[0064] Optionally, step 101 is specifically: according to the test working condition input condition, a start test operation is performed in the upper device; according to the variable association relationship between the upper device and the simulation model and the start test operation, the model variable parameter control of the simulation model is performed, the differential lock switch variable is obtained; the differential lock switch variable is input into the simulation device, the simulation device performs numerical voltage conversion, outputs and obtains the differential lock switch signal; the differential lock switch signal is input into the differential lock controller, so that the differential lock controller runs, and a response signal is obtained.

[0065] In the embodiment, after the HIL test engineering is developed and debugged, a format that can be recognized by the upper device software is compiled and generated, the hardware-in-the-loop device includes but is not limited to the HIL cabinet and the upper device, the upper device includes but is not limited to the host computer, and the HIL cabinet includes but is not limited to the simulation model and the simulation device. In the embodiment, the host computer and the HIL cabinet are taken as examples for corresponding description, and the host computer software will also develop corresponding controls associated with the model variables for model parameter control. The wheel differential lock switch model inputs the “wheel differential lock switch” signal to the differential lock controller to be tested, the differential lock controller will work according to the software design, the host computer wheel differential lock switch mathematical value change (such as from 0 to 1), the control associated model variable (i.e. the wheel differential lock switch in the simulation model) will also change from 0 to 1, and is given to the I / O board card through the interface module of the simulation model and the simulation device; then the I / O board card converts the given wheel differential lock switch value (mathematical value) into a voltage signal (electrical physical value) and inputs it to the differential lock controller, the differential lock controller runs according to its own logic, and the differential lock controller can calculate the wheel differential lock switch state after receiving the wheel differential lock switch voltage signal (electrical physical value), and outputs the response signal of the wheel differential lock switch state.

[0066] Step 102: input the response signal into the simulation model through the simulation device, drive the simulation model to work according to the test working condition input condition and the response signal, and obtain the simulation state of the differential lock feedback switch.

[0067] Optionally, step 102 specifically includes steps 1021 to 1024, and each step is specifically as follows:

[0068] Step 1021: input the response signal into the simulation model through the simulation device, input the response signal into the simulation device, and the simulation device performs numerical voltage conversion to output and obtain the response variable.

[0069] Optionally, the simulation device includes an I / O board card module, a bus simulation board card module, a program-controlled power supply module, and a real-time processor module.

[0070] The I / O board card module is used for simulating output of an electrical signal required by the differential lock controller, receiving an output electrical signal of the differential lock controller, and converting the output electrical signal into variable data for identification of the simulation model; the bus simulation board module is used for providing a physical interface between a communication bus of the differential lock controller and the simulation model, converting the variable of the simulation model into a differential pressure signal for identification of the differential lock controller, and converting the differential pressure signal sent by the differential lock controller into variable data for identification of the simulation model.

[0071] The program-controlled power supply module is used for providing power supply for conversion of the output electrical signal of the I / O board card module.

[0072] The real-time processor module is used for core control of the simulation device and coordinated control of the modules.

[0073] In this embodiment, the simulation device converts the variable data identified by the simulation model and the electrical signal required by the differential lock controller to be measured into each other, so that the simulation model and the differential lock controller can effectively identify corresponding data and perform a response control action. The simulation device mainly includes an I / O board card, a bus simulation board card, a program-controlled power supply, a real-time processor, and the like. The main function of the I / O board card module is to simulate output of an electrical signal required by the differential lock controller to be measured, such as a high / low level signal and a resistance variable signal, and simultaneously receive an output electrical signal of the measured controller and convert the output electrical signal into a variable or data for identification of the model. The bus simulation board card module mainly provides a physical interface between a communication bus (such as a CAN) of the measured controller and the simulation model, converts the variable or data of the simulation model into a differential pressure signal (a CAN differential voltage signal) for identification of the measured controller, and converts the CAN differential pressure signal sent by the measured controller into a variable or data for identification of the model. The program-controlled power supply mainly provides a power supply source for conversion of the electrical signal of the I / O board card. The real-time processor is a core control unit of the simulation device and performs coordinated control between the board cards or modules.

[0074] Step 1022: according to the test working condition input condition, set the numerical state of the simulation model.

[0075] Optionally, step 1022 is specifically:

[0076] When the test working condition input condition is high-speed opening of the differential lock, turning opening of the differential lock, short circuit of the differential lock switch or short circuit of the electromagnetic valve; set the speed message of the virtual engine controller model to a preset first value; set the speed message of the virtual instrument controller model sent to the differential lock controller to a preset second value; and set the differential lock switch of the differential lock switch model to be closed, wherein the differential lock switch includes an inter-axle differential lock switch and an inter-wheel differential lock switch.

[0077] In this embodiment, the CAN speed message of the virtual engine controller model is set to be greater than the preset first value (for example, 550 rpm), so as to meet the precondition of the differential lock controller controlling the differential lock (after detecting that the engine is started, that is, the speed is greater than the preset second value (for example, 400 rpm), the differential lock controller will control the differential lock, and the inter-axle differential lock switch or the inter-wheel differential lock switch in the switch model is set to be closed. When the test working condition input condition is high-speed opening of the differential lock, the speed signal of the differential lock controller is derived from the instrument speed message, in this condition, the CAN message of the speed of the front axle sent by the virtual instrument controller model to the differential lock controller is changed (the speed is set to be high, for example, 60 km / h), then the inter-wheel or inter-axle differential lock switch signal of the differential lock switch model is operated, so that the differential lock controller receives the inter-wheel or inter-axle differential lock opening signal, and then the output result of the differential lock controller is observed, so as to judge whether the software function of the differential lock controller is designed as expected.

[0078] When the test working condition input condition is turning opening of the differential lock, the differential lock controller monitors whether the vehicle turns, which is derived from judging the speed difference of the left and right wheels of the steering axle sent by the virtual brake controller (if the speed of the left wheel is greater than the speed of the right wheel and lasts for a period of time, it is judged as left turning; if the speed of the right wheel is greater than the speed of the left wheel and lasts for a period of time, it is judged as right turning), in this condition, the CAN message of the speed of the left and right wheels of the front axle sent by the virtual brake controller to the differential lock controller is changed (the speed difference is set to exist), then the inter-wheel or inter-axle differential lock switch signal of the differential lock switch model is operated, so that the differential lock controller receives the inter-wheel or inter-axle differential lock opening signal, and then the output result of the differential lock controller is observed, so as to judge whether the software function of the differential lock controller is designed as expected.

[0079] When the test working condition input condition is short circuit of the differential lock switch, a short circuit is formed between the input pin of the differential lock switch model and the input power supply.

[0080] In the embodiment, when the test working condition input condition is the short circuit of the differential lock switch, the differential lock switch input pin is short-circuited with the HIL cabinet power supply, so as to form the state of the short circuit of the differential lock switch, and then the output result and fault alarm of the differential lock controller are observed, so as to judge whether the software function of the differential lock controller is designed as expected.

[0081] When the test working condition input condition is the short circuit of the electromagnetic valve, the pin of the differential lock controller is short-circuited with the input power supply.

[0082] In the embodiment, when the test working condition input condition is the short circuit of the electromagnetic valve, the differential lock controller electromagnetic valve output pin is short-circuited with the HIL cabinet power supply, so as to form the state of the short circuit of the electromagnetic valve, and then the output result and fault alarm of the differential lock controller are observed, so as to judge whether the software function of the differential lock controller is designed as expected.

[0083] Step 1023: input the response variable into the simulation model, and drive the simulation model to work, to obtain a differential lock feedback switch simulation state; wherein the differential lock feedback switch simulation state includes an inter-axle differential lock feedback switch simulation state and an inter-wheel differential lock feedback switch simulation state.

[0084] In the embodiment, after the response of the differential lock controller is converted into variable data, the simulation model is driven to work, to obtain the differential lock feedback switch simulation state, that is, the running result after the simulation model works, and the running result includes the inter-axle differential lock feedback switch simulation state and the inter-wheel differential lock feedback switch simulation state. The inter-axle differential lock feedback switch simulation state (inter-axle differential lock feedback switch) and the inter-wheel differential lock feedback switch simulation state (inter-wheel differential lock feedback switch state) are returned to the differential lock control.

[0085] Optionally, the simulation model includes a virtual controller model, a differential lock switch model and a differential lock load model;

[0086] The virtual controller model includes a virtual engine controller model, a virtual instrument controller model and a virtual brake controller model;

[0087] The virtual engine controller model is used for simulating the engine controller to send an engine speed message to the differential lock controller;

[0088] The virtual instrument controller model is used for simulating the instrument system to send a vehicle speed message to the differential lock controller;

[0089] The virtual brake controller model is used for simulating the brake controller to send a steering axle wheel speed to the differential lock controller;

[0090] The differential lock switch model is used for simulating the inter-wheel differential lock switch and the inter-axle differential lock switch, to output the inter-axle differential lock feedback switch simulation state and the inter-wheel differential lock feedback switch simulation state.

[0091] The differential lock load model comprises an inter-wheel differential lock working model and an inter-axle differential lock working model.

[0092] The inter-wheel differential lock working model is used for corresponding relationship between an output voltage of an inter-wheel differential lock control of a differential lock controller and a working state, and is associated with an inter-wheel differential lock feedback switch state.

[0093] The inter-axle differential lock working model is used for corresponding relationship between an output voltage of an inter-axle differential lock control of a differential lock controller and a working state, and is associated with an inter-axle differential lock feedback switch state.

[0094] In the embodiment, as shown in a simulation model diagram, Figure 2 the simulation model mainly comprises a differential lock switch model, a virtual controller model and a differential lock load model, the differential lock switch model, three virtual controller models (a virtual engine controller model, a virtual instrument controller and a virtual brake controller) are inputs of the differential lock controller, and the load model is an output of the differential lock controller. The virtual controller model comprises the virtual engine controller model, the virtual instrument controller model and the virtual brake controller model, and the three virtual controller models are in communication with the differential lock controller through CAN. The virtual engine controller model is mainly used for simulating the engine controller to send an engine speed message to the differential lock controller, the virtual instrument controller model is mainly used for simulating the instrument system to send a vehicle speed message to the differential lock controller, so as to meet the test requirements of different test conditions and limit start; and the virtual brake controller model is mainly used for simulating the brake controller to send a steering axle wheel speed to the differential lock controller to judge the turning state through the difference between left and right wheel speeds, so as to meet the test requirements of differential lock exiting during turning.

[0095] The differential lock gear switch model comprises simulation outputs of four gears, i.e., an inter-wheel differential lock switch, an inter-axle differential lock switch, an inter-wheel differential lock feedback switch and an inter-axle differential lock feedback switch, and each switch collection is low effective (0V).

[0096] The differential lock controller load model comprises the inter-wheel differential lock working model and the inter-axle differential lock working model. As shown in a differential lock controller load peripheral wiring principle, Figure 3 the simulation model is built according to the differential lock controller peripheral principle.

[0097] The inter-wheel differential lock working model is built through corresponding relationship between an output voltage of an inter-wheel differential lock control of a differential lock controller and a working state, the inter-wheel differential lock working state is shown in Table 1, and is associated with a feedback switch output state, so as to ensure that the electrical logic is consistent with the actual vehicle state. During the test, whether the differential lock controller controls the inter-wheel differential lock working according to the input condition is checked, so as to determine whether the software function of the differential lock controller is normal.

[0098] Table 1: Wheel differential lock working state

[0099]

[0100] The working model of the inter-axle differential lock is built by the corresponding relationship between the inter-axle differential lock control output voltage and the working state of the differential lock controller. The working state of the inter-axle differential lock is shown in Table 2, and is associated with the output state of the feedback switch to ensure that the electrical logic is consistent with the actual vehicle state. During testing, whether the differential lock controller controls the inter-axle differential lock to work according to the input conditions is checked to determine whether the software function of the differential lock controller is normal.

[0101] Table 2: Inter-axle differential lock working state

[0102]

[0103] Step 103: input the differential lock feedback switch simulation state into the differential lock controller through the simulation device to make the differential lock controller run and obtain the actual result; wherein the actual result includes the differential lock control output voltage and the fault prompt.

[0104] Optionally, step 103 is specifically:

[0105] In the upper device, whether the differential lock controller controls the wheel differential lock working model and the inter-axle differential lock working model to work according to the test working condition input condition is observed, and whether the actual result of the differential lock controller running is the same as the expected result is checked to test whether the software function of the differential lock controller is normal;

[0106] The expected result is the expected output result of the differential lock controller according to the test working condition input condition.

[0107] In this embodiment, the differential lock feedback switch simulation state is input into the differential lock controller, the differential lock feedback switch simulation state is returned to the differential lock controller, the differential lock controller performs subsequent closed-loop servo control, and the actual result is obtained. The actual result of the differential lock controller under normal test working condition is the differential lock control output voltage, including the inter-axle differential lock control output voltage and the wheel differential lock control output voltage. Under the fault abnormal test working condition, after the differential lock controller outputs the inter-axle differential lock working, the inter-axle differential lock feedback switch needs to be closed at this time on the actual vehicle. Then the differential lock controller will collect the state of the feedback switch. If the differential lock controller has output the differential lock working but has not received the feedback switch closing, the differential lock controller will give a fault prompt and report the fault "differential lock fault".

[0108] Step 104: comparing the actual result with the expected result, testing the function of the differential lock controller; wherein the expected result is the expected output result of the differential lock controller according to the test case input condition.

[0109] In the embodiment, the actual result of the differential lock controller to be tested is compared with the expected result of the test case condition, the differential lock controller software is designed according to the function specification (controller software function logic description file), and the function specification is the necessary input condition for the differential lock controller software design. The input condition, output expected result and the like of each test case or test case are designed in the test case according to the function specification. The test is set according to the test condition input condition, the required input signal is given to the differential lock controller, and then the output expected result is compared with the actual output result of the controller. If they are consistent, it is judged that the controller software function is normal, otherwise it is not normal. Through the host computer test interface, whether the "inter-axle differential lock control output" or "inter-wheel differential lock control output" of the differential lock controller is 24V (i.e. representing the working state) is checked. Taking the high-speed differential lock opening condition as an example, the differential lock is not allowed to be opened in the actual high-speed condition. If the observed result during the test is 24V, the condition does not pass, and if the observed result during the test is 0V, the condition test passes.

[0110] According to the differential lock switch signal of the test condition or the input condition of the case, the differential lock switch signal is input as the input signal of the differential lock controller to be tested. The differential lock controller outputs a response signal after running according to its own function logic. The response signal is input into the simulation model through the simulation device according to the test condition input condition and the response signal. The differential lock feedback switch simulation state of the simulation model is output. The differential lock feedback switch simulation state is input into the differential lock controller through the simulation device. The differential lock controller runs according to its own function logic. The differential lock control output voltage and fault alarm are fed back and output. The actual result is compared with the expected result of the test condition input condition. The function of the differential lock controller is tested. Whether the differential lock controller is normal is judged. The simulation device and the simulation model simulate the real vehicle environment. The software function of the differential lock controller can be tested before the vehicle is installed. The development and installation progress of the whole vehicle are not affected. The real vehicle debugging and rectification period is reduced. Different test condition input conditions are provided according to different test conditions or cases. The simulation model can simulate multiple running conditions to provide the required input signal for the differential lock controller. The differential lock controller runs according to the input signal and its own function logic. The actual running result is output. The software function of the differential lock controller is tested under different conditions. The safety of the test process and the coverage of the function test are improved.

[0111] Embodiment two

[0112] Accordingly, referring to Figure 4 , Figure 4 is the structure diagram of the second embodiment of the test system of the differential lock controller function provided by the present application. As Figure 4 shown, the hardware-in-the-loop simulation device 401 and the differential lock controller 402; wherein the hardware-in-the-loop simulation device 401 executes the test method of the differential lock controller function.

[0113] The hardware-in-the-loop simulation device 401 includes a simulation model, a simulation device and an upper device.

[0114] The connection diagram is shown in Figure 5 , the differential lock controller is connected with one end of the simulation device, the other end of the simulation device is connected with one end of the simulation model, and the other end of the simulation model is connected with the upper device.

[0115] By implementing the embodiments of the present application, the test system of the differential lock controller function can realize the software function test of the differential lock controller, and is not affected by the whole vehicle development and the vehicle installation progress; the test system can realize the physical test of the software function of the differential lock controller before the vehicle installation, find out the problem points in advance, reduce the subsequent real vehicle debugging and rectification period, shorten the vehicle development period; can simulate the test of various working conditions that cannot be safely and conveniently carried out in the real vehicle test environment, such as the dangerous working condition test of opening the differential lock at high speed and turning, and the fault test of the differential lock switch short circuit and the electromagnetic valve short circuit, and can improve the test coverage.

[0116] The above specific embodiments further illustrate the purpose, technical solutions and beneficial effects of the present application. It should be understood that the above description is only for specific embodiments of the present application and is not used to limit the protection scope of the present application. It is particularly pointed out that for those skilled in the art, any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method of testing a differential lock controller function, characterized by, The method comprises the following steps: According to the test condition input condition, the differential lock switch signal is obtained, the differential lock switch signal is input into the differential lock controller, the differential lock controller is operated, and a response signal is obtained; wherein the test condition input condition includes high-speed differential lock opening condition, turning differential lock opening condition, differential lock switch short circuit and electromagnetic valve short circuit; The response signal is input into the simulation model through the simulation device, the simulation model is driven to work according to the test condition input condition and the response signal, and a differential lock feedback switch simulation state is obtained; The differential lock feedback switch simulation state is input into the differential lock controller through the simulation device, so that the differential lock controller is operated, and an actual result is obtained; wherein the actual result includes differential lock control output voltage and fault prompt; The actual result and the expected result are compared, and the function of the differential lock controller is tested; wherein the expected result is the expected output result of the differential lock controller according to the test condition input condition; Wherein, the simulation device is used to input the response signal into the simulation model, the response signal is input into the simulation device, the simulation device is used for numerical voltage conversion, and a response variable is output and obtained; According to the test condition input condition, the numerical state of the simulation model is set, specifically: when the test condition input condition is any one of the high-speed differential lock opening condition, the turning differential lock opening condition, the differential lock switch short circuit and the electromagnetic valve short circuit; the speed message of the virtual engine controller model is set to a preset first value; the speed message of the virtual instrument controller model sent to the differential lock controller is set to a preset second value; the differential lock switch of the differential lock switch model is closed, and the differential lock switch includes an inter-axle differential lock switch and an inter-wheel differential lock switch; The response variable is input into the simulation model, and the simulation model is driven to work, and the differential lock feedback switch simulation state is obtained; wherein the differential lock feedback switch simulation state includes an inter-axle differential lock feedback switch simulation state and an inter-wheel differential lock feedback switch simulation state. According to the test condition input condition, the differential lock switch signal is obtained, the differential lock switch signal is input into the differential lock controller, the differential lock controller is operated, and a response signal is obtained; wherein the test condition input condition includes high-speed differential lock opening condition, turning differential lock opening condition, differential lock switch short circuit and electromagnetic valve short circuit; 2. The method of claim 1, wherein the test of the differential lock controller function is performed by a controller of the vehicle. According to the test condition input condition, the simulation model is started in the upper device; According to the variable association relationship between the upper device and the simulation model and the start test operation, the model variable parameter control of the simulation model is performed, and a differential lock switch variable is obtained; The differential lock switch variable is input into the simulation device, the simulation device is used for numerical voltage conversion, and the differential lock switch signal is output and obtained; ​ The differential lock switch signal is input into the differential lock controller to make the differential lock controller operate, output and obtain the response signal.

3. The method of claim 1, wherein the test of the differential lock controller function is performed by a controller of the vehicle. The numerical state of the simulation model is set according to the test working condition input condition, and specifically: When the test working condition input condition is that the differential lock switch is short-circuited, a short circuit is formed between the input pin of the differential lock switch model and the input power supply; When the test working condition input condition is that the electromagnetic valve is short-circuited, a short circuit is formed between the pin of the differential lock controller and the input power supply.

4. The method of claim 3, wherein the test of the differential lock controller function is performed by: The response variable is input into the simulation model to drive the simulation model to work, and the differential lock feedback switch simulation state is obtained, wherein the simulation model comprises a virtual controller model, the differential lock switch model and a differential lock load model; The virtual controller model comprises the virtual engine controller model, the virtual instrument controller model and a virtual brake controller model; The virtual engine controller model is used for simulating the engine controller to send an engine speed message to the differential lock controller; The virtual instrument controller model is used for simulating the instrument system to send a vehicle speed message to the differential lock controller; The virtual brake controller model is used for simulating the brake controller to send a steering axle wheel speed to the differential lock controller; The differential lock switch model is used for simulating the inter-wheel differential lock switch and the inter-axle differential lock switch, and outputs the inter-axle differential lock feedback switch simulation state and the inter-wheel differential lock feedback switch simulation state; The differential lock load model comprises an inter-wheel differential lock working model and an inter-axle differential lock working model; The inter-wheel differential lock working model is used for associating with the inter-wheel differential lock feedback switch state according to the output voltage and working state correspondence relationship of the inter-wheel differential lock control of the differential lock controller; The inter-axle differential lock working model is used for associating with the inter-axle differential lock feedback switch state according to the output voltage and working state correspondence relationship of the inter-axle differential lock control of the differential lock controller.

5. The method of testing the differential lock controller function of claim 4, wherein, The actual result and the expected result are compared to test the function of the differential lock controller, and specifically: In the upper device, whether the differential lock controller controls the inter-wheel differential lock working model and the inter-axle differential lock working model to work according to the test working condition input condition is observed, and whether the actual result of the differential lock controller running is the same as the expected result is checked to test whether the software function of the differential lock controller is normal; The expected result is an expected output result of the differential lock controller according to the test working condition input condition.

6. The method of testing the differential lock controller function of claim 1, wherein, The response signal is input into the simulation model through the simulation device, the simulation model is driven to work according to the test working condition input condition and the response signal, and the differential lock feedback switch simulation state is obtained, wherein the simulation device comprises an I / O board card module, a bus simulation board card module, a program-controlled power supply module and a real-time processor module; The I / O card module is configured to simulate output of electrical signals required by the differential lock controller, receive output electrical signals of the differential lock controller, and convert the output electrical signals into variable data for identification by the simulation model. The bus simulation module is configured to provide a physical interface between a communication bus of the differential lock controller and the simulation model, convert variable data of the simulation model into a differential pressure signal for identification by the differential lock controller, and convert the differential pressure signal from the differential lock controller into the variable data for identification by the simulation model. The programmable power supply module is configured to provide power for conversion of the output electrical signals of the I / O card module. The real-time processor module is configured to perform core control of the simulation device and coordinate control of the modules.

7. A system for testing differential lock controller functionality, comprising: The hardware-in-the-loop simulation device and the differential lock controller, wherein the hardware-in-the-loop simulation device performs a test method of the differential lock controller function as claimed in any one of claims 1 to 6. The hardware-in-the-loop simulation device includes a simulation model, a simulation device, and an upper device. One end of the differential lock controller is connected to the simulation device, another end of the simulation device is connected to one end of the simulation model, and another end of the simulation model is connected to the upper device. ​

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