CN110597225A - CAN bus-based vehicle body controller product offline detection equipment and test method - Google Patents

Abstract

The invention provides a CAN bus-based vehicle body controller product offline detection device and a CAN bus-based vehicle body controller product offline detection method. The invention has strong universality, the design of the PCB test board is adopted, a commercial test board card is not adopted, the equipment construction cost can be greatly reduced, the off-line detection equipment can be repeatedly utilized, testers do not need to participate in the operation in the test process, the upper computer test software programs and modifies the test sequence according to the product difference, the test time is reduced, the input and output signals of the tested BCM are automatically tested and judged by the test equipment, the human errors are reduced, and the test accuracy is improved.

Description

CAN bus-based vehicle body controller product offline detection equipment and test method

Technical Field

The invention belongs to the technical field of automobile electronic part and automobile body controllers, and particularly relates to an offline detection device and a test method for an automobile body controller product based on a CAN bus

Background

The automobile Body Controller (BCM) becomes an indispensable part of an automobile, the use of a vehicle-mounted relay CAN be reduced, the automobile electric appliances of the automobile CAN be effectively controlled, a driver controls an internal and external lighting system, a central control lock system, a front and rear wiper system, a glass skylight system, a rearview mirror system and the like of the automobile according to an external environment, and the BCM integrates CAN/LIN bus network control. Off-line detection is an important link for ensuring the quality of a vehicle body controller before loading, the testing of the vehicle body controller by utilizing CAN data communication becomes a main trend in the market at present, the Control of input and output of the vehicle body controller through IO Control is the most common testing method based on the diagnosis service of BCM products, the efficiency of off-line detection is improved by combining a computer for automatic testing, and the manufacturing cost of off-line detection equipment is high due to a series of digital and communication board cards for automatic testing such as an Agilent test board card, an NI board card and a VT test board card for auxiliary testing at present.

Disclosure of Invention

In view of the above, the present invention is directed to provide an offline inspection apparatus for a vehicle body controller product based on a CAN bus, so as to reduce the manufacturing cost of the offline inspection apparatus for the vehicle body controller, improve the inspection efficiency, and simplify the testing process.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

a CAN bus-based vehicle body controller product offline detection device comprises a programmable power supply, a PCB test board, a test fixture, a load box, a CAN communication tool, an upper computer and a load module;

the program control power supply is used for supplying power to the PCB test board, the test fixture and the load box and controlling the power supply of the tested BCM;

the PCB test board is used for carrying out validation of corresponding digital input signals, collection of BCM output signals, validation of analog signal input, CAN bus communication, validation of PWM input signals and power supply input on a tested BCM;

the test fixture and the load box are used for simulating the state of the electric appliance of the whole vehicle and realizing the power consumption of the tested BCM after the output of the tested BCM is effective by connecting power resistors in series;

the CAN communication tool is used for transmitting CAN bus signals and sending and receiving signal commands;

and the upper computer sends a test command through the CAN bus control and waits for test feedback to judge a test result.

Furthermore, the output signal of the PCB test board adopts a universal four-channel independently selected switch driving chip for realizing digital high-low effective output and providing the high-effective input signal and the low-effective input signal of the tested BCM, meanwhile, a plurality of resistor circuits are designed at the switch end of the driving chip, the serial connection of different resistance values to the ground is realized, the output of different AD signals is realized, the test of different AD inputs of the tested BCM is realized, the tested BCM judges whether the input channel is normal by reading different AD values, the input signal adopts an extended input acquisition 151 chip, a plurality of input acquisitions can be realized, the high-low effective acquisition is carried out on the output of the tested BCM, and the extended input channel meets the universality test of the tested BCM.

Further, the PCB circuit comprises a switch circuit, a low effective switching value acquisition circuit and a high effective switching value acquisition circuit.

Further, the switch circuit comprises a channel multifunctional switch chip U1, an IN1 pin of the U1 is grounded through a pull-down resistor R1 and is connected to a control output pin CRT1 of the MCU, the CRT1 can pull the IN1 to a high level, an S1A pin of the U1 is connected with a VSS power supply, a D1 pin is connected with a board card output pin OUT1, and a S1B pin is grounded; a VSS pin of the U1 is connected with a system power supply VSS, and a GND pin is connected with a system ground GND; the S2B pin of U1 is connected with system power VSS, the D2 pin is connected with a board card output OUT2, the IN2 pin is connected to the ground through a pull-down resistor R2 and is connected to a control output pin CRT2 of the MCU, and the CRT2 can pull the IN1 to a high level; an IN3 pin of U1 is grounded through a pull-down resistor R3 and is connected to a control output pin CRT3 of the MCU, and the CRT3 can pull IN1 to be high level; the pin S3A of the U1 is grounded through a variable resistor R5, the pin D3 is connected with a card output pin OUT3, and the pin S3B is suspended; the VDD pin of the U1 is connected with the MCU power supply VDD; pin IN4 of U1 is connected to ground through pull-down resistor R4 and to the MCU's control output pin CRT4, and CRT4 pulls IN1 high. The pin S4A of U1 is grounded through a variable resistor R6, the pin D4 is connected with the output pin OUT4 of the card, and the pin S4B is suspended.

Furthermore, the low effective switching value acquisition circuit is used for testing a low effective output circuit of the tested BCM, L-IN is a low effective input signal and corresponds to a low effective output signal of the tested BCM, the L-IN signal is connected to a system power supply VSS through a pull-up resistor R10 and is connected to the ground through a capacitor C1, and C1 is used for signal filtering and anti-static; is connected to the input pins HC151-DX of the expansion chip HC151 through the series resistor R11 and the ground parallel capacitor C2.

Further, the high-effective switching value acquisition is used for testing a high-effective output circuit of the tested BCM, H-IN is a high-effective input signal and corresponds to the high-effective output signal of the tested BCM, the H-IN signal is grounded through a filter capacitor C3 and a pull-down resistor R12, C3 is used for signal filtering and static electricity prevention, and R12 is used for pulling down the H-IN signal to a low level when the BCM is not output; is connected to the input pins HC151-DX of the expansion chip HC151 through the series resistor R13 and the ground parallel capacitor C2.

Furthermore, the test fixture adopts a mechanical structure of a relay control electromagnetic valve, and the automatic connection test of the tested BCM comprises an external relay, an electromagnetic valve, an indicator light, a metal contact switch and a photoelectric sensor.

Furthermore, the interface of the upper computer adopts a visual window design, manual debugging and automatic testing are realized, manual testing is divided into digital input, analog input and digital output testing, a CAN sending function is called through a switch button to carry out a testing command of the BCM to be tested, and the BCM to be tested and the PCB board card to be tested are controlled.

The invention also aims to provide a test method of the offline detection equipment of the vehicle body controller product based on the CAN bus, which comprises the following specific implementation processes:

inputting and testing: a PCB test board gives a corresponding effective mode to the input end of the BCM to be tested, then the upper computer sends and reads a corresponding input state to the BCM to be tested through a CAN bus, and the corresponding ineffective mode also needs to be tested;

and (3) output test: the upper computer sends a corresponding message instruction through the CAN bus to control the effective output of the tested BCM, and then the tested BCM output voltage is tested through the PCB test board;

power supply: the power supply input of the BCM to be tested is provided by a program control power supply for indirect testing;

ground: the test is performed indirectly through the program control power supply;

CAN communication: indirect testing;

LIN communication: based on fault code testing, the board card simulates an LIN slave node, an upper computer enables an LIN signal of a BCM, whether the LIN slave node is lost or not is detected through a message, and the loss sends an error message to the upper computer.

Compared with the prior art, the offline detection equipment and the offline detection method based on the CAN bus automobile body controller product have the following advantages that:

the invention has strong universality, the design of the PCB test board is adopted, a commercial test board card is not adopted, the equipment construction cost can be greatly reduced, the off-line detection equipment can be repeatedly utilized, testers do not need to participate in the operation in the test process, the upper computer test software programs and modifies the test sequence according to the product difference, the test time is reduced, the input and output signals of the tested BCM are automatically tested and judged by the test equipment, the human errors are reduced, and the test accuracy is improved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of a switching circuit according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a low effective switching value acquisition circuit according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a high effective switching value acquisition circuit according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a test fixture according to an embodiment of the present invention;

fig. 5 is a schematic diagram of a visualization interface of the upper computer software according to the embodiment of the present invention;

FIG. 6 is a schematic diagram illustrating a fixture testing process according to an embodiment of the present invention;

fig. 7 is a schematic diagram of an offline detection device and a testing method for a vehicle body controller product based on a CAN bus according to an embodiment of the present invention.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention. Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.

The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

The invention provides a product offline detection device based on a CAN bus automobile body controller, which comprises the following components:

the test device comprises a program control power supply, a PCB test board, a test fixture load box, a CAN communication hardware tool, an upper computer and a load module.

The program control power supply mainly supplies power to the PCB test board, the test fixture and the load, and simultaneously needs to control the power supply of the BCM to be tested.

The PCB test board is designed by adopting a product similar to BCM, and is divided into a digital input signal, a digital output signal, a CAN bus, a LIN bus, a PWM signal output signal and the like based on the function of a single chip microcomputer, and the PCB test board is mainly used for carrying out validity of the corresponding digital input signal, collection of the BCM output signal, validity of analog signal input, CAN bus communication, validity of the PWM input signal, power input and the like on the tested BCM.

The PCB test board circuit design, the output signal adopts a universal four-channel independently selected switch driving chip, the digital high-low effective output can be realized, the digital high-low effective output is provided for the high-effective input signal and the low-effective input signal of the tested BCM, meanwhile, the design of the peripheral circuit is carried out at the switch end of the driving chip, the design of various resistor circuits is adopted, the series connection of different resistance values to the ground can be realized, the output of different AD signals can be realized, the test on different AD inputs of the tested BCM can be realized, and the tested BCM judges whether the input channel is normal or not by reading different AD values. The input signal adopts the extension input acquisition 151 chip, can realize many input acquisitions, carries out the effectual collection of height to the output of the BCM that is tested, and extension input channel can satisfy the commonality test of the BCM that is tested.

As shown in fig. 1, the circuit is a U1, which is a four-channel multifunctional switch chip, and the type is ADG1334, and the operating principle is that when the level of the input INX of a certain channel is high, the corresponding output channel DX and SXA are connected; DX is connected to SXB when INX is low.

The connection relationship of the circuit is as follows: pin IN1 of U1 is connected to ground through pull-down resistor R1 and to the MCU's control output pin CRT1, and CRT1 pulls IN1 high. The pin S1A of U1 is connected with VSS power supply, the pin D1 is connected with the output pin OUT1 of the board card, and the pin S1B is grounded; a VSS pin of the U1 is connected with a system power supply VSS, and a GND pin is connected with a system ground GND; the S2B pin of U1 is connected with system power VSS, the D2 pin is connected with a board card output OUT2, the IN2 pin is connected to the ground through a pull-down resistor R2 and is connected to a control output pin CRT2 of the MCU, and the CRT2 can pull the IN1 to a high level; an IN3 pin of U1 is grounded through a pull-down resistor R3 and is connected to a control output pin CRT3 of the MCU, and the CRT3 can pull IN1 to be high level; the pin S3A of the U1 is grounded through a variable resistor R5, the pin D3 is connected with a card output pin OUT3, and the pin S3B is suspended; the VDD pin of the U1 is connected with the MCU power supply VDD; pin IN4 of U1 is connected to ground through pull-down resistor R4 and to the MCU's control output pin CRT4, and CRT4 pulls IN1 high. The pin S4A of U1 is grounded through a variable resistor R6, the pin D4 is connected with the output pin OUT4 of the card, and the pin S4B is suspended.

The working process is as follows: OUT1 and OUT2 are used for a high/low effective switching value acquisition channel of a tested BCM; when the CRT1 (or CRT2) outputs a high level, OUT1 (or OUT2) is turned on with S1A (or S2A), outputting a high level. When the CRT1 (or CRT2) outputs low level, or no output, the IN1 (or IN2) pin is pulled down to low level by the pull-down resistor R1 (or R2); OUT1 (or OUT2) is turned on with S1B (or S2B), outputting a low level. OUT3 and OUT4 are used to test the analog acquisition channels of the BCM under test. When a CRT3 (or a CRT4) outputs a high level, OUT3 (or OUT4) is connected with S3A (or S4A), the ground is connected through a variable resistor R5 (or R6), and tests on different analog quantity acquisition channels of the tested BCM can be realized by adjusting the resistance value of R5 (or R6); when the CRT3 (or CRT4) outputs low level, or no output, the IN3 (or IN4) pin is pulled down to low level by the pull-down resistor R3 (or R4); OUT3 (or OUT4) and S3B (or S4B) are conductive, and at this time OUT3 (or OUT4) has no output, which is equivalent to being grounded through an infinite resistor. The tested BCM judges whether the AD values are normal or not by reading different AD values.

The low effective switching value acquisition circuit is shown in fig. 2 and can be used for testing a tested BCM low effective output circuit.

The connection relationship is as follows: L-IN is an active low input signal corresponding to the active low output signal of the BCM under test. The L-IN signal is connected to a system power supply VSS through a pull-up resistor R10, is connected to the ground through a capacitor C1, and is used for signal filtering and anti-static through C1; is connected to the input pins HC151-DX of the expansion chip HC151 through the series resistor R11 and the ground parallel capacitor C2.

The working process is as follows: when the low active output signal of the tested BCM is not output, the L-IN signal is pulled up to the power supply level VSS by the pull-up resistor R10; when the low effective output signal of the tested BCM is output, the L-IN signal is pulled down to a low level; the MCU reads the level state of the input signal through the expansion chip HC151 and compares the level state with the output state of the BCM to judge whether the BCM works normally or not.

The high effective switching value acquisition circuit is shown in fig. 3, and can be used for testing a tested BCM high effective output circuit.

The connection relationship is as follows: H-IN is an active high input signal corresponding to the active high output signal of the BCM under test. The H-IN signal is grounded through a filter capacitor C3 and a pull-down resistor R12, C3 is used for signal filtering and static electricity prevention, and R12 is used for pulling the H-IN signal down to a low level when the BCM does not output; is connected to the input pins HC151-DX of the expansion chip HC151 through the series resistor R13 and the ground parallel capacitor C2.

The working process is as follows: when the high effective output signal of the tested BCM is not output, the H-IN signal is pulled down to a low level by the pull-down resistor R12; when the high effective output signal of the tested BCM is output, the H-IN signal is pulled up to high level; the MCU reads the level state of the input signal through the expansion chip HC151 and compares the level state with the output state of the BCM to judge whether the BCM works normally or not.

The test fixture and the load box are mainly used for simulating the state of an electric appliance of the whole vehicle, the power consumption of the tested BCM after the output is effective is realized by connecting power resistors in series, the fixture adopts a mechanical structure controlled by an electromagnetic valve and is used for fixing the tested BCM and placing a product for testing, and the part can be additionally designed automatically and is designed through an air cylinder electromagnetic valve.

The testing fixture and the load box are designed in a universal way, the load box is used for displaying that the output of the BCM to be tested is replaced by power resistors with the same parameters, the load box is designed into a detachable plug shell in the design process, all the output is led out by rubber plugs, and thus the BCM can be externally connected with an actual load to be driven for verification; the test fixture is controlled by an electromagnetic valve and pneumatically connected, and the automatic connection test of the tested BCM is realized by combining the structures of the photoelectric sensor and the metal contact switch, and the specific test process is shown in figure 6.

The circuit of the test fixture adopts the working principle of a digital input and output control electromagnetic valve to realize the loading test of the BCM to be tested, and the test fixture comprises components such as an external relay, an electromagnetic valve, an indicator light, a metal contact switch, a photoelectric sensor and the like. The metal contact switch and the photoelectric sensor detect that the BCM to be tested is put into the test fixture, the upper cover of the fixture is closed, the result is fed back to the PCB test board, the PCB test board outputs a signal, the external relay 1 is closed, the cylinder is pushed upwards to be locked, and the test is started. After the test is successful, the electric appliance 2 is closed, the air cylinder is pushed down to be unlocked, and after the relay 4 is closed and the green light flickers, the test is successful. If the test fails in the test process, the relay 3 is turned on to flash the red light, the electric appliance 4 can be turned on only by pressing the red button, and the cylinder is pushed down to be unlocked. The schematic diagram is shown in fig. 4.

The design of the test fixture adopts a simple mechanical mechanism of a relay control electromagnetic valve to realize the processes of loading, testing and unloading of the BCM to be tested, input signal acquisition and output control signals can be provided by a test PCB, the test process is simple, the control method is reliable, and the cost is low.

The CAN communication tool is mainly used for transmitting CAN bus signals and sending and receiving signal commands.

The upper computer software is developed based on NET Freenetwork, a test case of a BCM to be tested is compiled by using a C code, the upper computer sends a test command through CAN bus control and waits for test feedback to judge a test result, USB-CAN equipment is adopted for interaction between the upper computer software and the outside, and specific hardware CAN be a Zhou Li Gong or a kvaser series CAN card.

The upper computer interface adopts a visual window design, manual debugging and automatic testing CAN be realized, manual testing is divided into digital input, analog input and digital output testing, a CAN sending function is called through a switch button to carry out a testing command of a BCM to be tested, and the BCM to be tested and a PCB board card are controlled. The automatic test mainly calls an automatic test script written by a lower computer code, automatically runs a test program, displays a test result in an automatic test message window, and automatically generates a test report in a TXT format after the test is finished.

The upper computer software has a visual interface, can be classified according to the test type of the BCM to be tested, and provides interfaces with the following functions for users: 1. initializing CAN communication equipment and carrying out transparent transmission test; 2. BCM low-significance and high-significance digital input tests; 3. BCM simulation input test; 4. BCM digital output test.

The main functions of the upper computer in the test system are as follows: 1. the CAN bus is connected with the PCB test board, and the PCB test board and the tested BCM are controlled through CAN information, so that the whole test process is controlled; 2. the CAN message and the test details on the bus CAN be displayed in real time, each test operation and result performed by a user are recorded, and the results are stored into a test log file in a TXT format for reference.

The tested BCM needs to be filled with product test codes, and mainly relates to bus signal transmission after input signals are effective, effective output after receiving effective bus command output, CAN receiving and transmitting signal processing and the like. The part of processing is subsequently integrated into product codes, so that information interaction test with upper computer software and a test board card is realized, and the aim of testing the BCM is fulfilled.

The test process of the invention is as follows:

the digital signal input test is divided into a tested BCM input valid process and a tested BCM input valid command reading process, as shown in FIG. 7, the flow of the tested BCM digital input valid process is 1-3-5, and the flow of the tested BCM digital input valid command reading process is 1-7-6-2. In the testing process, the testing command is transmitted and judged through the CAN bus all the time, the digital effective command of the tested BCM is executed through the testing board card, the digital input effective state of the tested BCM is sent by the tested BCM, and the final testing result is judged by the upper computer, so that the complete testing process is realized.

Firstly, an upper computer sends a BCM input test command to a PCB test board through a CAN bus, after the PCB test board receives the test BCM input command, a corresponding channel outputs a high-low effective signal to a tested BCM, and at the moment, the digital input of the tested BCM is effective; then delaying for 200ms, sending a corresponding hardware channel digital input test command to the tested BCM by the upper computer through the CAN bus, and sending the input state of the corresponding channel of the BCM to the upper computer by the tested BCM through the CAN bus according to the added code; and finally, the upper computer receives the tested BCM input state signal and then judges, if the command is a valid command, the test is successful, and if the command is an invalid command, the test is failed.

Analog input signal test is similar to digital input signal test, except that hardware change is carried out on a test board card, compared with 12V high-effective of digital input signals and low-effective of grounding wires, analog input signals are subjected to voltage division through resistors externally connected with different resistance values and resistance values of a tested BCM analog input circuit, analog input of a tested BCM single chip microcomputer acquires different AD values, analog input effectiveness is achieved, the test flow is 1-3-5, and command reading flow after the tested BCM acquires corresponding analog input is 1-7-6-2.

Firstly, an upper computer sends BCM analog input to a PCB test board through a CAN bus, and the PCB test board is connected with a tested BCM through a chip to control resistors with different resistance values and then is connected to a ground wire, so that different AD analog signals are effective; then delaying for 200ms, sending a simulation input test command with a corresponding channel number to the tested BCM by the upper computer through the CAN bus, and sending an analog signal AD value acquired by the test to the upper computer by the tested BCM through the bus; and finally, the upper computer judges according to the AD value sent by the BCM to be tested, the AD value is in the range conforming to the effective command, the test is successful, and if the fed back AD value is not in the range, the test fails.

The digital output signal test comprises two parts, namely a tested BCM output effective part and an output effective command interpretation part, as shown in a schematic diagram 1, the tested BCM output effective process is 1-7-8-9, the tested BCM outputs a detection command process 1-3-4-2, an upper computer firstly sends a test command to enable the output of the tested BCM to be effective in the test process, then sends the test command to a PCB test board through a bus to carry out BCM output signal acquisition of a corresponding channel, and finally judges a test result according to a CAN signal sent by the PCB test board to finish the output test process of the BCM.

Firstly, an upper computer sends a test digital output signal command to a tested BCM through a CAN bus, after the tested BCM receives a bus signal, a corresponding output channel is effective, high-effective output is 12V, low-effective output is grounded, an external clamp is required to perform matching test for testing the digital output signal, and a power resistor is required to be connected in series with the output end of the tested BCM; then delaying for 200ms, sending a corresponding channel output test command to the PCB test board by the upper computer, and sending a tested BCM output signal to the upper computer through a CAN bus signal after an input acquisition circuit in the PCB test board acquires the tested BCM output signal; and finally, the upper computer judges according to the CAN signal sent by the test board card, the tested BCM outputs an effective test, and the test fails if the BCM outputs an effective command.

The method comprises the following steps that (1) PWM signal input test is carried out, the PWM signal input test is similar to digital input, a specific pin of a singlechip in a test board card is used as a PWM output port, a software clock comparator is arranged, a PWM waveform with a certain frequency is output, and the effective mode of the PWM signal of a tested BCM is met; the testing process is still initiated by the upper computer, firstly, a PWM input signal testing command is sent to the testing board card, after the testing board card receives a CAN bus command, a corresponding singlechip pin outputs a PWM waveform to the tested BCM, then, after the tested BCM receives the PWN waveform, the PWM waveform is sent to the upper computer in an effective mode through a CAN bus, and the upper computer judges whether the testing is successful or not according to a bus signal sent by the tested BCM.

And the LIN bus signal test is to integrate an LIN module in the test board card as a slave node of the BCM to be tested for testing the LIN signal. Firstly, an upper computer sends a test LIN signal command to a test board card through a CAN bus, and the test board card receives the command and then enables a corresponding LIN sending signal; then after 200ms of delay, the upper computer sends a LIN communication command to be tested for BCM test, the BCM master node carries out LIN signal request and sends the LIN signal request to the test board card, and the BCM sends the upper computer with CAN bus message whether the LIN slave node is lost or not; and finally, the upper computer judges according to the CAN bus signal sent by the BCM, and if the slave node is judged not to be lost, the test is successful.

In the whole BCM offline detection equipment test process, an automatic test sequence is compiled according to a hardware schematic diagram and PIN definition of the BCM, an upper computer test interface CAN be programmed by using CAPL in the test process to send CAN signal instructions, sending rules CAN be carried out according to own rules of component manufacturers, CAN signal receiving instructions are judged, the test result of a certain test sequence CAN be recorded in the test process, and finally the test result CAN be stored in a TXT format after the test is finished to generate a test report. The test result can be fed back through the PCB test board, the test success control clamp automatically pops open the tested BCM and prompts the test success, the test failure needs to manually open the test clamp, and the BCM is replaced for the following test.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims (9)

1. The utility model provides a based on CAN bus automobile body controller product check out test set that rolls off production line which characterized in that: the test device comprises a program control power supply, a PCB test board, a test fixture, a load box, a CAN communication tool, an upper computer and a load module;

the program control power supply is used for supplying power to the PCB test board, the test fixture and the load box and controlling the power supply of the tested BCM;

the PCB test board is used for carrying out validation of corresponding digital input signals, collection of BCM output signals, validation of analog signal input, CAN bus communication, validation of PWM input signals and power supply input on a tested BCM;

the test fixture and the load box are used for simulating the state of the electric appliance of the whole vehicle and realizing the power consumption of the tested BCM after the output of the tested BCM is effective by connecting power resistors in series;

the CAN communication tool is used for transmitting CAN bus signals and sending and receiving signal commands;

and the upper computer sends a test command through the CAN bus control and waits for test feedback to judge a test result.

2. The CAN bus-based vehicle body controller product offline detection device of claim 1, wherein: the PCB test board output signal adopts a universal four-channel independently selected switch driving chip for realizing digital high-low effective output, and provides high-effective input signals and low-effective input signals for a tested BCM, meanwhile, a plurality of resistor circuits are designed at the switch end of the driving chip, so that different resistor values are connected to the ground in series, the output of different AD signals is realized, the test of different AD inputs of the tested BCM is realized, the tested BCM judges whether the input channel is normal by reading different AD values, the input signal adopts an extended input acquisition 151 chip, a plurality of input acquisitions can be realized, the high-low effective acquisition is carried out on the output of the tested BCM, and the extended input channel meets the universality test of the tested BCM.

3. The CAN bus-based vehicle body controller product offline detection device of claim 2, wherein: the PCB circuit comprises a switch circuit, a low effective switching value acquisition circuit and a high effective switching value acquisition circuit.

4. The CAN bus based vehicle body controller product offline detection device of claim 3, wherein: the switch circuit comprises a channel multifunctional switch chip U1, wherein an IN1 pin of U1 is grounded through a pull-down resistor R1 and is connected to a control output pin CRT1 of the MCU, the IN1 can be pulled to be at a high level by the CRT1, an S1A pin of U1 is connected with a VSS power supply, a D1 pin is connected with a card output pin OUT1, and an S1B pin is grounded; a VSS pin of the U1 is connected with a system power supply VSS, and a GND pin is connected with a system ground GND; the S2B pin of U1 is connected with system power VSS, the D2 pin is connected with a board card output OUT2, the IN2 pin is connected to the ground through a pull-down resistor R2 and is connected to a control output pin CRT2 of the MCU, and the CRT2 can pull the IN1 to a high level; an IN3 pin of U1 is grounded through a pull-down resistor R3 and is connected to a control output pin CRT3 of the MCU, and the CRT3 can pull IN1 to be high level; the pin S3A of the U1 is grounded through a variable resistor R5, the pin D3 is connected with a card output pin OUT3, and the pin S3B is suspended; the VDD pin of the U1 is connected with the MCU power supply VDD; an IN4 pin of the U1 is grounded through a pull-down resistor R4 and is connected to a control output pin CRT4 of the MCU, the CRT4 can pull an IN1 to be high level, an S4A pin of the U1 is grounded through a variable resistor R6, a D4 pin is connected with a card output pin OUT4, and an S4B pin is suspended.

5. The CAN bus based vehicle body controller product offline detection device of claim 3, wherein: the low effective switching value acquisition circuit is used for testing a low effective output circuit of the tested BCM, L-IN is a low effective input signal and corresponds to a low effective output signal of the tested BCM, the L-IN signal is connected to a system power supply VSS through a pull-up resistor R10 and is connected to the ground through a capacitor C1, and C1 is used for signal filtering and anti-static; is connected to the input pins HC151-DX of the expansion chip HC151 through the series resistor R11 and the ground parallel capacitor C2.

6. The CAN bus based vehicle body controller product offline detection device of claim 3, wherein: the high-effective switching value acquisition is used for testing a high-effective output circuit of a tested BCM, H-IN is a high-effective input signal and corresponds to the high-effective output signal of the tested BCM, the H-IN signal is grounded through a filter capacitor C3 and a pull-down resistor R12, C3 is used for signal filtering and static electricity prevention, and R12 is used for pulling down the H-IN signal to a low level when the BCM is not output; is connected to the input pins HC151-DX of the expansion chip HC151 through the series resistor R13 and the ground parallel capacitor C2.

7. The CAN bus-based vehicle body controller product offline detection device of claim 1, wherein: the test fixture adopts a mechanical structure of a relay control electromagnetic valve, and is used for automatically connecting and testing the tested BCM, and comprises an external relay, an electromagnetic valve, an indicator lamp, a metal contact switch and a photoelectric sensor.

8. The CAN bus-based vehicle body controller product offline detection device of claim 1, wherein: the interface of the upper computer adopts a visual window design, manual debugging and automatic testing are realized, manual testing is divided into digital input, analog input and digital output testing, a CAN sending function is called through a switch button to carry out a testing command of a BCM to be tested, and the BCM to be tested and a PCB board card to be tested are controlled.

9. The test method for the offline detection equipment based on the CAN bus automobile body controller product is characterized by comprising the following steps: the method comprises the following detection processes:

inputting and testing: a PCB test board gives a corresponding effective mode to the input end of the BCM to be tested, then the upper computer sends and reads a corresponding input state to the BCM to be tested through a CAN bus, and the corresponding ineffective mode also needs to be tested;

and (3) output test: the upper computer sends a corresponding message instruction through the CAN bus to control the effective output of the tested BCM, and then the tested BCM output voltage is tested through the PCB test board;

power supply: the power supply input of the BCM to be tested is provided by a program control power supply for indirect testing;

ground: the test is performed indirectly through the program control power supply;

CAN communication: indirect testing;

LIN communication: based on fault code testing, the board card simulates an LIN slave node, an upper computer enables an LIN signal of a BCM, whether the LIN slave node is lost or not is detected through a message, and the loss sends an error message to the upper computer.