WO2023065620A1

WO2023065620A1 - Ethercat bus-based wiring harness test method and apparatus

Info

Publication number: WO2023065620A1
Application number: PCT/CN2022/087300
Authority: WO
Inventors: 王家斌
Original assignee: 上海赞太科技有限公司
Priority date: 2021-10-20
Filing date: 2022-04-18
Publication date: 2023-04-27
Also published as: CN113933754A

Abstract

An EtherCAT bus-based wiring harness test method and apparatus. The apparatus comprises a bench, and further comprises: M wiring harness adapters all installed on the bench, the M wiring harness adapters being configured to be connected to a wiring harness to be tested; N test nodes all installed under the bench, the N test nodes being sequentially connected and configured to be connected to the M wiring harness adapters; a direct-current power supply installed on the bench, the direct-current power supply being configured to provide an adjustable direct-current power supply voltage for the N test nodes; and an industrial personal computer installed on the bench, the industrial personal computer being connected to the N test nodes by means of EtherCAT buses, wherein the industrial personal computer sends a wiring harness test instruction by means the EtherCAT buses, tests, by means of the N tests nodes, the wiring harness to be tested connected to the M wiring harness adapters, and generates a test report after the test is completed.

Description

Wire harness testing method and device based on EtherCAT bus

technical field

The present application relates to the technical field of electronic detection, and in particular to a wire harness testing method and device based on an EtherCAT bus.

Background technique

In the fields of automobile, aviation, industrial control, etc., a large number of wiring harnesses of various types are used. The correctness of the connection of the wiring harness and the correctness of the parameters of the functional components in the wiring harness are related to whether a device can work reliably. The wiring harness test is to test the wiring components connected to various electrical components in the device and the functional components such as resistors and diodes contained in the wiring harness. Generally, it is necessary to measure the conduction of the wiring harness and the parameters of functional components.

The existing wiring harness testing device adopts the method of cascading multiple wiring motherboards, and the wiring harness adapters to be tested are sequentially connected to the test terminal arrays of the wiring motherboards. The lumped installation and deployment of test devices is complicated and error-prone. In actual production, when the wiring harness under test needs to adjust the connection relationship between the wiring harness adapter and the wiring board in a local area due to design changes, the entire test device needs to be re-deployed, which has poor flexibility. In addition, the existing wire harness testing devices generally use bus technologies such as RS485 (maximum 10 Mbps), CAN (maximum 1 Mbps) and other bus technologies to transmit test data. As the complexity of the wiring harness to be tested increases, the test data and the total transmission distance also increase accordingly. The communication rate of this type of bus can no longer meet the needs of efficient production. Limited by the communication speed, the existing wire harness testing device can only test one connection of the wire harness to be tested at a time, and the production efficiency is low.

Moreover, bus technologies such as RS485 and CAN used by current test devices cannot accurately locate the specific position where each test node is connected in the bus. The first test node starts to check each test node connected to the bus one by one, and the fault repair takes a lot of time.

Obviously, the current wiring harness testing method has the problems of poor flexibility, slow communication speed, low production efficiency, and time-consuming fault repair.

Contents of the invention

Based on this, it is necessary to address the above technical problems and provide a wire harness testing method and device based on the EtherCAT bus that can achieve high flexibility, fast communication speed, high production efficiency, and short maintenance time.

Technical scheme of the present invention is as follows:

A wire harness testing device based on the EtherCAT bus, including a machine table, also includes:

M wire harness adapters are installed on the machine platform, and the M wire harness adapters are used to connect with the wire harness to be tested;

N test nodes are all installed under the machine platform, and the N test nodes are connected in turn and are used to connect with the M described harness adapters;

A DC power supply is installed on the machine platform, and the DC power supply is used to provide an adjustable DC power supply voltage for the N test nodes; an industrial computer is installed on the machine platform, and the industrial computer is connected to the N said test nodes. The test node is connected through the EtherCAT bus, and the industrial computer sends a harness test command through the EtherCAT bus, and tests the harnesses to be tested connected to the M harness adapters through the N test nodes, and generates a test report after the test is completed.

Specifically, each of the N test nodes includes a test terminal array, an excitation measurement module, a microprocessor, and an EtherCAT controller, and the number of the test terminal arrays is multiple, and each of the test terminal arrays is used to communicate with M The connecting terminals of the wire harness adapter are connected, the excitation measurement module is connected with the test terminal array and the DC power supply, the microprocessor is connected with the test terminal array through an SPI data interface or an I2C data interface, and the The microprocessor is also connected with the excitation measurement module, the EtherCAT controller is connected with the microprocessor through the SPI data interface or the I2C data interface, one end of the EtherCAT controller is connected with an RJ45_1 interface, and the EtherCAT controller The other end is connected to an RJ45_2 interface, the RJ45_1 interface is connected to the RJ45_2 interface of the test node on the left side of the test node where it is currently located, and the RJ45_2 interface is connected to the RJ45_1 interface of the test node on the right side of the test node where it is currently located connect.

Specifically, the test terminal array is an ordered collection of a group of test terminals, and there are multiple test terminals in one test terminal array.

Specifically, the excitation measurement module includes a plurality of sampling devices and a plurality of sampling switches, both ends of each of the sampling devices are connected to the microprocessor, and the sampling switches are arranged on the sampling devices, the signal ground , Between the excitation output terminal VS of the DC power supply and the common line.

Specifically, the wire harness testing device based on the EtherCAT bus also includes a scanning gun and a label printer, both of which are connected to the industrial computer and are used to input or output label information and test results of the wire harness to be tested .

Specifically, a kind of wire harness test method based on EtherCAT bus, described wire harness test method is based on described wire harness test device, and described method comprises the following steps:

Step 1: the industrial computer obtains the topology description of the wiring harness to be tested, the configuration data on the machine platform, and the node basic information of each test node of N;

Step 2: The industrial computer sends a wiring harness test instruction through the EtherCAT bus, controls each test node to start an internal self-test according to the wiring harness test instruction, and obtains the connection status on the test terminal of each test node, and maps it to the wiring harness to be tested. topologically;

Step 3: After the internal self-test is successful, generate the group data of the test terminal;

Step 4: Execute the harness test in a single test node, and judge whether the harness test in a single test node is successful;

Step 5: If the harness test in a single test node is successful, execute the harness test between multiple test nodes, and judge whether the harness test between multiple test nodes is successful;

Step 6: If the harness test between multiple test nodes is successful, perform a short circuit test;

Step 7: Generate a test report according to the short-circuit test results.

Specifically, in step two: control each test node to start internal self-test according to the wiring harness test instruction, and the specific steps include:

Step 2-1: Construct a self-test loop based on the test terminals of the test node for internal self-test;

Step 2-2: Calculate the current internal resistance of the test terminal based on the self-test loop;

Step 2-3: Judging whether the internal resistance is less than the preset correction threshold, if it is judged that the internal resistance is less than the preset correction threshold, the connection function of the test terminal is normal, if it is judged that the internal resistance is greater than the preset The corrected threshold value of the test terminal connection is not functioning properly.

Specifically, Step 4: Execute the harness test within a single test node, and the specific steps include:

Step 4-1: Obtain a test node for conducting a harness test within a single test node, and construct a measurement loop based on the test terminals of the test node;

Step 4-2: Calculate the resistance value of the line L to be tested based on the measurement circuit;

Step 4-3: If the resistance value of the line L to be tested is less than the preset conduction threshold, the test result is conduction; if the resistance value of the line L to be tested is greater than the preset open circuit threshold, the test result is open circuit, Otherwise, the test result is high resistance.

Specifically, Step 3: When the internal self-test is successful, generate the grouped data of the test terminals, and then include the following steps:

When the internal self-test fails, the fault diagnosis and repair of the test node are carried out.

Specifically, in step 4: judging whether the wire harness test in a single test node is successful, and in step 5: judging whether the wire harness test among multiple test nodes is successful, and then including:

If it is judged that the wire harness test within a single test node is unsuccessful or the wire harness test between multiple test nodes is judged to be unsuccessful, all errors of the test terminals are checked and repaired.

The present invention realizes technical effect as follows:

The above-mentioned wire harness testing method and device based on the EtherCAT bus are successively provided with a machine platform, and M wire harness adapters, N test nodes, a DC power supply and an industrial computer, and the industrial computer is connected to the N test nodes through the EtherCAT bus, The industrial computer sends a wire harness test command through the EtherCAT bus, and tests the wire harnesses to be tested connected to the M wire harness adapters through the N test nodes, and generates a test report after the test is completed, and can be connected through only one EtherCAT bus All test nodes of the wiring harness to be tested use the 100Mbps EtherCAT bus to transmit test data. The communication speed is fast, which simplifies the installation and deployment work and process of the system. It has high flexibility, fast communication speed, high production efficiency, and realizes time-consuming fault repair short effect;

The installation and deployment of the test node only needs to plug and unplug two RJ45 terminals, and the installation and deployment method is simple; when the wiring harness to be tested needs to be adjusted in the topology of a local area, it has good flexibility;

The wiring harness to be tested is divided into several connection sets, and the test method in a single test node, the test method between multiple test nodes and the short-circuit test method of the harness terminal can be executed in parallel on multiple connection sets in the connection set at the same time, and the production efficiency is high. ;

Through the wire harness test device based on the EtherCAT bus, the self-test method, grouping method, test method within a single test node, test method between multiple test nodes, wire harness terminal short circuit test method and test node fault diagnosis can be expanded. method to improve production efficiency;

Each test node (slave station) has unique position information in the EtherCAT bus, and the position information increases sequentially from the first test node. When a fault occurs at a test node, the fault diagnosis method proposed by the invention can quickly find the faulty test node, reducing the time for fault maintenance.

Description of drawings

The accompanying drawings constituting a part of this application are used to provide further understanding of the present invention, and the schematic embodiments and descriptions of the present invention are used to explain the present invention, and do not constitute an improper limitation of the present invention. In the attached picture:

Fig. 1 is the structural block diagram of the wire harness testing device based on EtherCAT bus in an embodiment;

Fig. 2 is the structural block diagram of test node in the wiring harness testing device based on EtherCAT bus line in an embodiment;

Fig. 3 is the structural block diagram of test terminal array in the wiring harness testing device based on EtherCAT bus line in an embodiment;

Fig. 4 is the structural block diagram of excitation measurement module in the wiring harness testing device based on EtherCAT bus line in an embodiment;

Fig. 5 is a block diagram of the connection state between the test nodes performing the test terminal grouping process in one embodiment;

Fig. 6 is the structural diagram when carrying out the self-test of test node in an embodiment;

Fig. 7 is a structural block diagram of an example when performing fault diagnosis of a test node in an embodiment;

Fig. 8 is an example structural block diagram of testing in a single test node in one embodiment;

Fig. 9 is an example structural block diagram of testing between multiple test nodes in one embodiment;

Fig. 10 is a structural block diagram of an example of performing a short circuit test on a wire harness terminal in an embodiment.

Detailed ways

Specific embodiments of the present invention will be described in detail below. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention. These all belong to protection domain of the present invention.

It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and examples.

In order for those skilled in the art to better understand the solution of the present invention, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the present invention. Obviously, the described embodiment is only It is an embodiment of a part of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall belong to the protection scope of the present invention.

It should be noted that the terms "first", "second", "step 1", "step 2" and the like in the description and claims of the present invention and the above drawings are used to distinguish similar objects and do not necessarily Used to describe a specific sequence or sequence. It is to be understood that the data so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein can be practiced in sequences other than those illustrated or described herein. Furthermore, the terms "comprising" and "having", as well as any variations thereof, are intended to cover a non-exclusive inclusion.

In one embodiment, as shown in Figure 1, a kind of wire harness testing device based on EtherCAT bus is provided, including machine platform, described wire harness testing device based on EtherCAT bus also includes:

M wire harness adapters are all installed on the machine platform, and the M wire harness adapters are used to connect with the wire harness to be tested; wherein, the wire harness to be tested is composed of several wires and connectors. The connectivity of the wires and the parameters of the components are tested. The wire harness adapter is a connecting device that connects the wiring terminals of the wire harness to be tested with the test terminals of the test node.

N test nodes are all installed under the machine platform, and the N test nodes are connected in sequence and used to connect with the M harness adapters; wherein, the test nodes are designed based on the EtherCAT controller. The test node is connected to the EtherCAT bus through two RJ45 interfaces, which is easy to install and deploy, and has good flexibility. The test terminals in the test node are connected to the wiring terminals of the wire harness to be tested through the wire harness adapter, and multiple wire harness adapters can be connected to each test node, and multiple test nodes can also be connected to a single wire harness adapter.

A DC power supply is installed on the machine, and the DC power supply is used to provide adjustable DC power supply voltages for the N test nodes; wherein, the DC power supply voltage and current amplitude of the adjustable DC power supply voltage can be adjusted according to the wiring harness to be tested needs to be set.

The industrial computer is installed on the machine platform, the industrial computer is connected to the N test nodes through the EtherCAT bus, the industrial computer sends the wiring harness test command through the EtherCAT bus, and the M wiring harnesses are passed through the N test nodes. Test the wiring harness to be tested connected by the adapter, and generate a test report after the test is completed. Among them, all test nodes are connected to the industrial computer through the EtherCAT bus. Each test node receives test instructions from the test program through the EtherCAT bus, builds a test loop between a single test node or multiple test nodes through the switch in the test node, sets the measurement stimulus, collects the test response signal in the test loop and returns to the test program.

Specifically, the industrial computer has a data memory and two Ethernet interfaces. One of the Ethernet interfaces connects N test nodes through the EtherCAT bus, and the other Ethernet interface is used to connect to external networks such as MES systems.

EtherCAT is an industrial Ethernet field bus proposed by German BECKHOFF company, which has the characteristics of synchronous data transmission, high real-time performance, flexible system structure topology, and data bandwidth up to 100Mbps.

The EtherCAT data frame is developed based on the standard 100M Ethernet data frame, and uses a dedicated real-time protocol to achieve high-speed, high-synchronization, and high-real-time characteristics. EtherCAT encodes the communication data of all slave stations in EtherCAT data frames. Each slave station reads the corresponding output data of the master station when the EtherCAT data frame passes through its node, and at the same time inserts the input data of the master station into the corresponding position of the EtherCAT data frame, thereby realizing parallel data transmission between the master station and all slave stations .

In this embodiment, an ordinary industrial computer is used as the master station, and a specially designed test node is used as the slave station. The EtherCAT bus has a flexible topology, and the connection between the master station and the slave station is simple.

In one embodiment, as shown in Figure 2, the N test nodes all include a test terminal array, an excitation measurement module, a microprocessor and an EtherCAT controller, and the number of the test terminal arrays is multiple, each of the The test terminal array is used to be connected to the wiring terminals of the M wire harness adapters, the excitation measurement module is connected to the test terminal array and the DC power supply, and the microprocessor is connected to the The test terminal array is connected, the microprocessor is also connected with the excitation measurement module, the EtherCAT controller is connected with the microprocessor through the SPI data interface or the I2C data interface, and one end of the EtherCAT controller is connected to a RJ45_1 interface, the other end of the EtherCAT controller is connected to an RJ45_2 interface, the RJ45_1 interface is connected to the RJ45_2 interface of the test node on the left side of the currently located test node, and the RJ45_2 interface is connected to the currently located test node Connect the RJ45_1 interface of the test node on the right. Specifically, all test nodes are connected to a common ground wire, ensuring that the internal circuits of each test node use the same reference ground. And all test nodes share a common line, which is used to assist the harness test method and build a test loop. The test node is connected to a DC power supply through a 2-core power cable, and the internal power supply module converts it into a power supply of various voltages required.

Wherein, the microprocessor (MCU) is used as the main control unit, and the digital-to-analog converter (DAC) integrated in the MCU is used to provide a programmable voltage to the excitation measurement module, and the programmable voltage is isolated and amplified as a voltage in the measurement circuit. excitation. The multi-channel analog-to-digital converter (ADC) integrated in the MCU is used to collect parameters such as voltage and current in the measurement loop, and obtain the resistance value of the measured object in the measurement loop after calculation. The test node supports the measurement of parameters of wire harnesses or functional components such as resistors and diodes.

In addition, the test node can expand the test terminal array, increase the number of test terminals of a single test node, and support the testing of complex wire harness connectors. The test node can also control color sensors, airtight sensors and other sensors to perform special function tests through data interfaces (such as SPI, I2C, etc.).

Further, the EtherCAT controller is used to realize the communication function of the EtherCAT bus. The EtherCAT controller can be an independent chip such as AX58100, ET1100, LAN9252, or an EtherCAT controller integrated in an MCU chip such as AX58200.

Furthermore, the transmission process of the test data is as follows: first, the EtherCAT controller receives the EtherCAT data frame from the previous test node through the RJ45_1 interface, obtains the test instruction from it, and transmits it to the MCU through the data transmission interface SPI for processing after parsing. The test result data transmitted by the MCU to the EtherCAT controller through the data transmission interface SPI is written into the EtherCAT data frame, and then transmitted to the next test node through the RJ45_2 interface. The EtherCAT data frames are transmitted sequentially between the test nodes according to the topology until the last test node.

After the last test node detects that there is no next test node, the EtherCAT data frame is transmitted to the RJ45_2 interface of the last test node through its RJ45_1 interface. According to the topological structure, the test nodes are input from their RJ45_1 interface in turn, and the EtherCAT data frame is output from its RJ45_2 interface until it finally reaches the test software of the master station industrial computer for processing.

In one embodiment, as shown in FIG. 3 , the test terminal array is an ordered collection of a group of test terminals, and there are multiple test terminals in one test terminal array. The number of test terminals in an array can be flexibly configured as required. A test terminal array supporting 32 test terminals is shown in this embodiment, as shown in Figure 3, the MCU writes the switch control data of the test terminals into the corresponding When the output enable is valid, the switch control data Sx of the test terminal controls the switches SHx and SLx of each test terminal to perform actions.

The combination of switches SHx and SLx of a test terminal has 4 states, which are "disconnected", "connected to high-end", "connected to low-end", and "connected to high-end and low-end at the same time".

Specifically, "open" means that the test terminal is not connected to the measurement circuit. "Connected to the high end" means that the test terminal is connected to the excitation of the test node, which is the terminal with the high potential in the measurement circuit. "Connected to the low end" means that the test terminal is connected to the signal return terminal of the test node, which is the terminal with the low potential in the measurement circuit. "Simultaneously connected to high-end and low-end" means that the test terminal is connected to the internal test circuit of the test node, which is used to self-test the test terminal, calculate the internal resistance of the test terminal, and judge the correctness of the function of the test terminal.

Further, the switch of the test terminal can be implemented by using MOS transistors, MOS relays, and mechanical relays.

In one embodiment, as shown in Figure 4, the excitation measurement module includes a plurality of sampling devices and a plurality of sampling switches, both ends of each of the sampling devices are connected to the microprocessor, and the sampling switches are set to Between the sampling device, the excitation output terminal VS of the DC power supply and the common line. In this embodiment, the sampling device is a resistor. Taking the number of sampling devices as 2 as an example, the number of sampling switches is 2 as an example. As shown in Figure 4, the excitation measurement module includes 4 ADC voltage sampling channel, which can simultaneously collect 4 voltage values across two current-limiting resistors R1 and R2, namely voltage VH2, voltage VH1, voltage VL2 and voltage VL1. Among them, the excitation VS is a programmable DC power output, and the MCU can program the excitation voltage in the measurement circuit by setting the output value of the DAC. Switch S1 is used to switch the internal excitation or common line. The switch S2 is used to switch the signal ground or the common line. The common line is used for cascading test nodes, and a measurement loop can be constructed between two or more test nodes.

In one embodiment, the wire harness testing device based on the EtherCAT bus also includes a scanning gun and a label printer, both of which are connected to the industrial computer and are used to input or output the label information and label information of the wire harness to be tested. Test Results.

In one embodiment, a kind of wire harness test method based on EtherCAT bus, described wire harness test method is based on described wire harness test device, and described method comprises the following steps:

Specifically, the wire harness to be tested is connected to multiple test nodes through a plurality of wire harness connectors, and the present invention groups the wire harness terminals according to the topological structure of the wire harness to be tested before performing the wire harness test.

As shown in Figure 5, the test terminal grouping method is explained:

Wherein, the wiring harness to be tested is composed of connections L1, L2, L3, L4, L5, L6, and L7, which can be recorded as H={L1, L2, L3, L4, L5, L6, L7}. Further, each connection is composed of two test terminals, such as L2=(IOA1,IOB1). First, initialize two empty connection sets H1 and H2, where H1 stores connections within a single node, and H2 stores connections between nodes. Then, for each connection L(IOx, IOy) in H, if IOx and IOy are in a single test node, store L(IOx, IOy) in the connection set H1; if T1 and T2 belong to different test nodes, Store L(IOx,IOy) into H2. Furthermore, the grouping results in FIG. 5 are H1={L1, L4, L5, L8, L11}, and H2={L2, L3, L6, L7, L9, L10}.

Since the test nodes work in parallel, this grouping method can improve the test speed.

Step 7: Generate a test report according to the short-circuit test results.

In one embodiment, as shown in Figure 6, in step 2: control each test node to start the internal self-test according to the wiring harness test instruction, and the specific steps include:

Specifically, in this step, as shown in Figure 6, before performing the wiring harness test, it is necessary to perform a diagnostic test on all test terminals of the test node to determine whether the function of the test terminals is normal. To stimulate VS, and connect to signal ground through switches SL and S2 at the same time, a self-test loop is constructed, which is described in step 2-1.

Then, collect four voltages VH1, VH2, VL2, VL1 at both ends of the two current-limiting resistors of the test loop, and calculate the internal resistance of the test terminal IOx: RL=(VH2-VL2)/((VH1-VH2)/ R1), if RL is less than the set correction threshold, it means that the connection function of the test terminal is normal, and RL/2 is stored in the test software as the internal correction value of the test terminal. If RL is greater than the set correction threshold, it means that the connection function of the test terminal is not normal, the self-test fails, and the hardware circuit of the test terminal needs to be further repaired and diagnosed. The self-test method of the test node is to execute the above-mentioned test process for each test terminal. Only after the self-test of all test terminals in the test node passes, the test terminal can be used to test the wire harness to be tested.

In one embodiment, as shown in Figure 7, step 3: after the internal self-test is successful, generate the packet data of the test terminal, and then include the following steps:

Further, as shown in Figure 7, the steps for performing fault diagnosis and repair of the test node are as follows:

First, in this embodiment, there are N test nodes. In the industrial computer, the test program is sent based on the EtherCAT data frame to scan the slave station on the EtherCAT bus, that is, the test node. Since the test node x+1 fails, the EtherCAT data frame loops back after being transmitted to the test node x, and returns to the master station of the test device, that is, the industrial computer.

Further, the industrial computer judges the number of test nodes passed by the EtherCAT data frame. If only x test nodes are scanned, and x<n, it means that the x+1th test node has failed. Then, the industrial computer sets the LED of the xth test node to "ON" state, indicating the faulty previous test node. Maintenance personnel use the "slave connection" cable of the xth test node to find the x+1th node for troubleshooting.

In one embodiment, as shown in FIG. 8, step 4: execute the wire harness test in a single test node, and the specific steps include:

Specifically, as shown in FIG. 8 , the test terminal IOx is connected to the excitation VS through the switches SHx and S1, and the test terminal IOy is connected to the signal ground through the switches SLy and S2, thereby constructing a measurement loop. This measurement loop is the measurement loop in step 4-1. Next, collect four voltages at both ends of the two current-limiting resistors of the measurement circuit, namely VH1, VH1, VL1 and VL2, and calculate the resistance value of the line L to be tested according to the following formula:

RL=(VH2-VL2)/((VH1-VH2)/R1);

Wherein, if RL is smaller than the set conduction threshold, the test result is conduction; if RL is greater than the set open circuit threshold, the test result is open circuit; otherwise, the test result is high resistance.

Further, if the measured object is a resistance, RL is the resistance value. If the object under test is a diode, perform the second test in reverse, judge the direction of the diode according to the resistance values of the two tests, and judge the threshold voltage of the diode according to the voltage difference VH2-VL2 of the two tests.

In one embodiment, as shown in Figure 3, after the tested wiring harness is grouped by test terminals, if H1 is not an empty set, the test program executes the test in a single node, and the test method is as follows:

(1) Initialize an empty command set REQ;

(2) For each connection L(IO1,IO2) in H1, if the test node where IO1 and IO2 are located is not in the test node to which the existing connection of REQ belongs, move L(IO1,IO2) from H1 to REQ , where IO1 is connected to the high-end potential, and IO2 is connected to the low-end potential;

(3) Generate a test command according to REQ and send it to the EtherCAT bus;

(4) The test nodes where all the test terminals stored in the REQ are located perform tests according to the REQ test instructions, and return the test results;

(5) The test program calculates and stores the test results of all connections stored in the REQ. If H1 is an empty set, it means that the connections in all nodes have been tested. If H1 is a non-empty set, continue to Step1 until H1 is an empty set.

According to the test terminal grouping in Figure 5, H1={L1, L4, L5, L8, L11}, the test in a single node needs to execute two instructions, REQ1={L1, L4, L8, L11}, REQ2={L5}. It can be seen that the present invention can execute tests in multiple test nodes in parallel to improve production efficiency.

In one embodiment, as shown in FIG. 9, in step five: if the harness test in a single test node is successful, then perform the harness test between multiple test nodes, the specific process is as follows:

As shown in FIG. 9, IOx of test node A is connected to excitation VS of node A through switches SHx, S1. The IOy of the test node B is connected to the signal ground through the switches SLy and S2, and a measurement loop is constructed.

Two voltages VH1 and VH2 are collected at both ends of the current limiting resistor R1 at node A. Two voltages VL2 and VL1 are collected at both ends of the current limiting resistor R2 of node B.

Calculate the resistance value of the line L to be tested according to the following formula:

RL=(VH2-VL2)/((VH1-VH2)/R1);

If RL is less than the set conduction threshold, the test result is conduction; if RL is greater than the set cut-off threshold, the test result is open circuit; otherwise, the test result is high resistance. If the measured object is a resistor, RL is the resistance value.

Further, similarly, if the measured object is a diode, the second test is performed in the reverse direction, the direction of the diode is judged according to the resistance values of the two tests, and the threshold voltage of the diode is judged according to the voltage difference VH2-VL2 of the two tests.

After the tested wire harness is grouped by the test terminals, if H2 is not an empty set, the test program executes the test between multiple nodes. The test method is as follows:

Step 1: Initialize an empty command set REQ;

Steps: For each connection L(IO1,IO2) in H2, if the test nodes where IO1 and IO2 are located are not in the test nodes where the existing connections of REQ belong, move L(IO1,IO2) from H2 to REQ, Among them, IO1 is connected to the high-end potential, and IO2 is connected to the low-end potential;

Step 3: Generate a test command according to REQ and send it to the EtherCAT bus;

Step 4: The test nodes where all the test terminals stored in the REQ are located execute the test according to the REQ test command and return the test result;

Step 5: The test program in the industrial computer calculates and stores the test results of all connections stored in the REQ. If H2 is an empty set, it means that the connection tests in all nodes are completed. If H2 is a non-empty set, continue to Step1 until H2 is an empty set.

According to the test terminal grouping in Figure 5, H2={L2, L3, L6, L7, L9, L10}, the test between multiple test nodes needs to execute three instructions, REQ1={L2, L10}, REQ2={L3, L9} , REQ2={L7}. It can be seen that the present invention can execute tests in multiple test nodes in parallel to improve production efficiency.

In one embodiment, as shown in Figure 10, in step 6, carry out short-circuit test and be used for ensuring that there is no electrical connection between each connection, connection and idle test terminal, specific steps are as follows: first connect all wiring harnesses to be tested Connections are grouped into networks.

Next, initialize an empty network set N, and each element net in N represents a set of test terminals.

Next, for each connection, it is judged whether the two test terminals of the connection are already in the N set. If the two test terminals do not exist in the existing N collection, create a new net and store the two test terminals in the net collection.

Wherein, if one of the test terminals is in the net of the existing N set, store the other test terminal in the net set. If two test terminals belong to two different net1 and net2 respectively, merge net1 and net1 into one net.

Further, a test terminal is taken from each net element of N to form a mutually exclusive test terminal set Prim.

Furthermore, initialize an empty instruction set REQ; initialize an empty test terminal set BAD, which is used to record short-circuited test terminals; select a test terminal from Prim to set it as a high-end potential, and set the remaining test terminals as a low-end potential, and Generate a test instruction REQ and send it to the EtherCAT bus; the test node where all the test terminals stored in the REQ are located executes the test according to the REQ test instruction and returns the test result; the test program calculates and stores the test results of all the test terminals of the REQ. If the resistance value between the test terminal for setting the high-end potential and the test terminal for setting the low-end potential is less than the set threshold, it means that there is a short circuit between the nets where these test terminals are located, and the net where these test terminals are located is used as a cluster storage into the BAD collection.

Finally, if the BAD set is not empty, each cluster in BAD indicates a short-circuit error, and this information is used for error diagnosis and troubleshooting.

Further, the following examples illustrate, as shown in FIG. 10, there are three connections L1, L2, L3 in the wire harness, and one free test terminal IOA3. Since L1 and L2 share the test terminal IOA2, three nets are calculated, namely net1 (IOA1, IOA2, IOB1), net2 (IOB2, IOB3), and net3 (IOA3). Take a test terminal from net1, net2, and net3 to form Prim (IOA1, IOB2, IOA3). Then set a high potential on the test terminal IOA1, and set a low potential on the test terminals IOB2 and IOA3 for testing. Because there is a short circuit between the test terminals IOB1 and IOB2, the test results on the three test terminals of the Prim are: IOA1 is high potential, IOB2 is high potential, and IOA3 is low potential. The test results show that IOA1 and IOB2 are short-circuited. All test terminals of net1 and net2 where the test terminals are located form an error cluster (IOA1, IOA2, IOB1, IOB2, IOB3).

In one embodiment, in step 4: judging whether the wire harness test in a single test node is successful, and in step 5: judging whether the wire harness test among multiple test nodes is successful, and then also including:

If it is judged that the wire harness test within a single test node is unsuccessful or the wire harness test between multiple test nodes is judged to be unsuccessful, the error checking and repair of the test terminals will be carried out.

The preferred embodiments of the invention disclosed above are only to help illustrate the invention. The preferred embodiments are not exhaustive in all detail, nor are the inventions limited to specific embodiments described. Obviously, many modifications and variations can be made based on the contents of this specification. This description selects and specifically describes these embodiments in order to better explain the principle and practical application of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is only limited by the claims and their full scope and equivalents. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention. Inside.

Those skilled in the art can understand that, in addition to realizing the system, device and each module provided by the present invention in a purely computer-readable program code mode, the system, device and each module provided by the present invention can be completely implemented by logically programming the method steps. Modules implement the same program in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers, and embedded microcontrollers, among others. Therefore, the system, device and each module provided by the present invention can be regarded as a hardware component, and the modules included in it for realizing various programs can also be regarded as the structure in the hardware component; A module for realizing various functions can be regarded as either a software program realizing a method or a structure within a hardware component.

Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be implemented through computer programs to instruct related hardware, and the computer programs can be stored in a non-volatile computer-readable memory In the medium, when the computer program is executed, it may include several instructions for enabling a single-chip microcomputer, a chip or a processor (processor) to execute all or part of the steps of the method described in the various embodiments of the present application. Wherein, any references to memory, storage, database or other media used in the various embodiments provided in the present application may include non-volatile and/or volatile memory. Non-volatile memory can include: U disk, mobile hard disk, read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), flash memory, magnetic disc, or disc, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDRSDRAM), Enhanced SDRAM (ESDRAM), Synchronous Chain Synchlink DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

In addition, various implementations of the embodiments of the present invention can also be combined arbitrarily, as long as they do not violate the idea of the embodiments of the present invention, they should also be regarded as the content disclosed in the embodiments of the present invention.

Claims

A wire harness testing device based on EtherCAT bus, comprising a machine, is characterized in that, also includes:

M wire harness adapters are installed on the machine platform, and the M wire harness adapters are used to connect with the wire harness to be tested;

N test nodes are all installed under the machine platform, and the N test nodes are connected in sequence and used to connect with the M wiring harness adapters; a DC power supply is installed on the machine platform, and the DC power supply is used for The N test nodes provide adjustable DC power supply voltage; the industrial computer is installed on the machine platform, and the industrial computer is connected to the N test nodes through the EtherCAT bus, and the industrial computer sends the wiring harness test through the EtherCAT bus An instruction to test the wire harnesses to be tested connected to the M wire harness adapters through the N test nodes, and generate a test report after the test is completed.
The wire harness testing device based on EtherCAT bus according to claim 1, wherein, N said test nodes all comprise test terminal arrays, excitation measurement modules, microprocessors and EtherCAT controllers, the number of said test terminal arrays There are multiple, each of the test terminal arrays is used to connect with the wiring terminals of the M wire harness adapters, the excitation measurement module is connected to the test terminal array and the DC power supply, and the microprocessor passes the SPI data Interface or one of the I 2 C data interface is connected with the test terminal array, the microprocessor is also connected with the excitation measurement module, and the EtherCAT controller is connected with the test terminal array through one of the SPI data interface or the I 2 C data interface. The microprocessor is connected, one end of the EtherCAT controller is connected to an RJ45_1 interface, and the other end of the EtherCAT controller is connected to an RJ45_2 interface, and the RJ45_1 interface is connected to the RJ45_2 of the test node on the left side of the test node where it is currently located. Interface connection, the RJ45_2 interface is connected to the RJ45_1 interface of the test node on the right side of the current test node.
The wire harness testing device based on the EtherCAT bus according to claim 2, wherein the test terminal array is an ordered collection of a group of test terminals, and there are multiple test terminals in one test terminal array.
The wire harness testing device based on EtherCAT bus according to claim 2, wherein the excitation measurement module includes a plurality of sampling devices and a plurality of sampling switches, and the two ends of each sampling device are connected to the microprocessor The sampling switch is arranged between the sampling device, the signal ground, the excitation output terminal VS of the DC power supply and the common line.
The wire harness testing device based on the EtherCAT bus according to any one of claims 1-4, wherein the wire harness testing device based on the EtherCAT bus also includes a scanning gun and a label printer, and the scanning gun and the label printer are all compatible with The industrial computer is connected.
A wire harness testing method based on EtherCAT bus, characterized in that, said wire harness testing method is based on the wire harness testing device according to any one of claims 1-5, said method comprising the following steps:

Step 1: the industrial computer obtains the topology description of the wiring harness to be tested, the configuration data on the machine platform, and the node basic information of each test node of N;

Step 2: The industrial computer sends a wiring harness test instruction through the EtherCAT bus, controls each test node to start an internal self-test according to the wiring harness test instruction, and obtains the connection status on the test terminal of each test node, and maps it to the wiring harness to be tested. topologically;

Step 3: After the internal self-test is successful, generate the group data of the test terminal;

Step 4: Execute the harness test in a single test node, and judge whether the harness test in a single test node is successful;

Step 5: If the harness test in a single test node is successful, execute the harness test between multiple test nodes, and judge whether the harness test between multiple test nodes is successful;

Step 6: If the harness test between multiple test nodes is successful, perform a short circuit test;

Step 7: Generate a test report according to the short-circuit test results.
The wire harness testing method based on the EtherCAT bus according to claim 6, wherein in step 2: control each test node to start internal self-test according to the wire harness test instruction, and the specific steps include:

Step 2-1: Construct a self-test loop based on the test terminals of the test node for internal self-test;

Step 2-2: Calculate the current internal resistance of the test terminal based on the self-test loop;

Step 2-3: Judging whether the internal resistance is less than the preset correction threshold, if it is judged that the internal resistance is less than the preset correction threshold, the connection function of the test terminal is normal, if it is judged that the internal resistance is greater than the preset The corrected threshold value of the test terminal connection is not functioning properly.
The wire harness testing method based on EtherCAT bus according to claim 6, wherein, step 4: execute the wire harness test in a single test node, and the specific steps include:

Step 4-1: Obtain a test node for conducting a harness test within a single test node, and construct a measurement loop based on the test terminals of the test node;

Step 4-2: Calculate the resistance value of the line L to be tested based on the measurement circuit;

Step 4-3: If the resistance value of the line L to be tested is less than the preset conduction threshold, the test result is conduction; if the resistance value of the line L to be tested is greater than the preset open circuit threshold, the test result is open circuit, Otherwise, the test result is high resistance.
The wiring harness testing method based on EtherCAT bus according to claim 6, it is characterized in that, step 3: after internal self-test success, generate the grouping data of test terminal, also comprise the following steps afterwards: when internal self-test failure, then carry out Test node troubleshooting fixes.
The wire harness testing method based on EtherCAT bus according to claim 6, wherein, in step 4: judge whether the wire harness test in a single test node is successful, and, in step 5: judge whether the wire harness test between a plurality of test nodes After success, it also includes: if it is judged that the harness test in a single test node is unsuccessful or the harness test between multiple test nodes is unsuccessful, then troubleshooting and repairing the test terminal errors are all performed.