FCT automatic detection system of production line ECU and detection method thereof

Abstract

The invention discloses an FCT automatic detection system of a production line ECU and a detection method thereof, and belongs to the field of vehicle brake control and automatic detection. The FCT automatic detection system comprises an industrial personal computer, a test unit, an execution unit, a programmable power supply and an FCT detection device; the FCT detection equipment comprises a translation test bench, a to-be-detected ECU positioned and connected to the translation test bench, and a lifting test mechanism arranged right above the to-be-detected ECU, the lifting test mechanism comprises a pressing unit and a test needle bed arranged at the output end of the bottom of the pressing unit, and the industrial personal computer is connected with a PCBA board of the to-be-detected ECU through the test unit, an execution unit and the test needle bed in sequence. The ECU to be tested is also connected with the industrial personal computer through a CAN bus and a programmable power supply. By adopting the FCT automatic detection system for the ECU of the production line and the detection method thereof, full-automatic testing of the ECU can be realized, excessive human intervention is not needed, the automation degree is high, and the FCT automatic detection system has the advantages of high accuracy of test data, high efficiency and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle brake control and automatic detection, and in particular to an FCT automatic detection system and a detection method of a production line ECU. Background Art

[0002] With the rapid development of the automotive industry and the advent of the era of intelligent driving, consumers' demand for automobiles is not limited to the growth in quantity, but is also reflected in the strong demand for intelligent cars. As the core component of the vehicle, the importance of the automotive chassis system is self-evident. Especially in the field of intelligent driving, the wire control brake system has become the main solution for modern automobile chassis braking control due to its significant advantages in performance, cost, volume and weight. It is also one of the foundations for realizing advanced intelligent driving. Therefore, how to ensure that the automated FCT test of the wire control brake system ECU has efficient, accurate and stable performance has become a major challenge currently faced.

[0003] For mass-produced ECUs (Electronic Control Units), FCT testing (Functional Circuit Test) is a key quality assurance method. FCT testing provides a simulated operating environment for the test object PCBA board (printed circuit board) so that it can run in various design states, thereby collecting parameters in each state to verify whether the functions of the PCBA board meet the design requirements.

[0004] However, the existing FCT test still has the following shortcomings: 1. Incomplete test coverage: Traditional testing methods often fail to cover all possible design states, resulting in some potential problems not being discovered in time. 2. Long testing time: As the testing process is complex and time-consuming, traditional methods are difficult to meet the needs of rapid production and efficient testing; 3. Inefficient testing: Inefficient testing processes not only increase production costs, but may also affect product quality; 4. Low test accuracy: The accuracy of traditional test methods is limited and cannot accurately reflect the performance of PCBA boards in actual working environments; 5. Low degree of automation: There are many manual operations, which can easily introduce human errors and also limit the speed and consistency of testing. Summary of the invention

[0005] The purpose of the present invention is to provide an FCT automatic detection system and detection method for a production line ECU to solve the above technical problems.

[0006] To achieve the above-mentioned purpose, the present invention provides an FCT automatic detection system for a production line ECU, comprising an industrial computer, a test unit, an execution unit, a programmable power supply and an FCT detection device, the FCT detection device comprising a translation test bench, an ECU to be tested positioned and connected to the translation test bench, and a lifting test mechanism arranged directly above the ECU to be tested, the lifting test mechanism comprising a pressing unit and a test needle bed arranged at the bottom output end of the pressing unit, the industrial computer is connected to the PCBA board of the ECU to be tested via the test unit, the execution unit and the test needle bed in sequence, and the ECU to be tested is also connected to the industrial computer via a CAN bus and a programmable power supply, respectively.

[0007] Preferably, the execution unit includes an EPB motor, a solenoid valve coil, a switch test assembly, a wheel speed sensor, a pressure sensor, a displacement sensor and an indicator light assembly; The test unit includes a data acquisition card, an electronic load and a wheel speed simulation card; The data acquisition card is respectively connected to the solenoid valve coil, the switch test assembly, the indicator light assembly, the pressure sensor, and the displacement sensor, and is used to collect output signals of the solenoid valve coil, the switch test assembly, the indicator light assembly, the pressure sensor, and the displacement sensor; The electronic load is connected to the EPB motor to drive the EPB motor to simulate operation according to the set mode; The wheel speed simulation card is connected to the wheel speed sensor and is used to drive the wheel speed sensor to simulate the wheel speed.

[0008] Preferably, the switch test assembly includes an AVH switch, an ESC switch, a HID switch, a BLS switch and an FLS switch; The indicator light assembly includes an EPB indicator light, an AVH indicator light and a HID indicator light.

[0009] Preferably, the translation test bench comprises a linear slide fixed on the workbench, a positioning fixture slidably arranged on the linear slide, the ECU to be tested is installed on the positioning fixture via a positioning column, and the positioning fixture is also connected to a translation cylinder installed on the workbench; An infrared sensor is arranged on the linear slide rail and facing the positioning fixture. The infrared sensor is connected to the PLC, and the PLC is connected to the downward pressure cylinder to detect whether there is an ECU to be tested on the positioning fixture. A proximity sensor is arranged on the linear slide rail and facing the positioning tooling. The proximity sensor is connected to the PLC, and the PLC is connected to the translation cylinder to detect whether the positioning tooling is in place.

[0010] Preferably, the pressing unit comprises a pressing cylinder fixed on the workbench via a support frame and a test needle bed arranged at the output end of the bottom of the pressing cylinder via a limit assembly; The limiting assembly includes a riveted top plate at the bottom end of the pressing cylinder, a mold changing pad arranged below the riveted top plate, and a riveted bottom plate fixed to the bottom end of the mold changing pad. The top end of the mold changing pad is fixedly connected to the bottom end of the joint bumping block, and the top end of the joint bumping block is vertically slidably connected to the riveted top plate. A limiting block is arranged on the riveted top plate and aligned with the top end of the joint bumping block, and a vertical limiting margin is left between the limiting block and the joint bumping block. The mold-changing pad is fixedly connected to the top of the test needle bed through the mold-changing fixed plate and the mold-changing sliding block in sequence, and the bottom of the test needle bed passes through the riveting bottom plate; The top of the test needle bed is also assembled and connected with a latch, a latch fixing block and a change-type cushion block in sequence.

[0011] Preferably, a buffer elastic pad is also provided between the bottom output end of the downward pressure cylinder and the riveting top plate.

[0012] Preferably, an infrared two-dimensional code scanner is provided at the input end of the infrared linear slide rail, a two-dimensional code is provided on the side of the ECU to be tested facing the infrared two-dimensional code scanner, and the infrared two-dimensional code scanner is connected to the PLC and is used to scan the two-dimensional code on the ECU to be tested through the infrared two-dimensional code scanner to form traceability information.

[0013] The detection method of the FCT automatic detection system of the production line ECU comprises the following steps: S1. At the input end of the linear slide rail, use the positioning column to install the ECU to be tested on the positioning fixture; S2. Start the translation cylinder, which drives the ECU to be tested to move along the linear slide rail until the infrared sensor detects that the ECU to be tested exists on the positioning fixture and the proximity sensor detects an in-position signal. The translation cylinder stops moving and starts the pressing cylinder. S3, the downward pressure cylinder drives the test needle bed downward until the joint collision block hits the limit block to prevent the downward pressure cylinder from moving downward. At this time, the probe on the test needle bed is inserted into the PCBA board of the ECU to be tested; S4, start the industrial computer to simulate multiple working conditions, collect the feedback signals of the ECU under test under each working condition, and detect the performance of the ECU under test according to the feedback signals; S5. After the test is finished, the PLC controls the downward pressure cylinder and the translation cylinder to reset in sequence, and removes the ECU to be tested.

[0014] Preferably, in step S2, while the positioning tool is moving along the linear slide rail, the two-dimensional code on the ECU to be tested is scanned by an infrared two-dimensional code scanner to obtain traceability information, and the traceability information is uploaded to the PLC.

[0015] Preferably, the simulating multiple working conditions described in step S4 includes: Normal voltage test: Use the probe on the test needle bed and the CAN message to detect whether the normal voltage of the test target point is 5V and the switch status of the indicator light component; Wheel speed test: read the frequency and period sent by the wheel speed simulation card. If the frequency is 800Hz, it is judged as normal; if the frequency is 1200Hz, it is judged as dynamic; Test of the solenoid valve coil: open the solenoid valve coil with a 50% PWM duty cycle, and read the current value on the programmable power supply. At the same time, read the CAN message flag to determine whether the solenoid valve coil is open. After the test, close the solenoid valve coil and restore the flag. Pressure sensor test: Send a 70% PWM duty cycle test signal to the pressure sensor, and read the flag bit through the CAN message to determine the working status of the pressure sensor; Displacement sensor test: Determine the working status of the displacement sensor by reading the voltage value of the programmable power supply corresponding to the displacement sensor point; EPB motor forward and reverse rotation test: Use the electronic load to simulate a constant resistance of 1R, read the electronic load current and CAN message flag, test the forward and reverse rotation of the EPB motor, and set the CAN message flag to 0 after the test; Power off the test, stop sending messages, and read the voltage of the test target point of the test bed of nails; EPB wake-up test: After the power-off test, use the relay to switch the switch state, release it after 50ms, and read the CAN message after waiting for 100ms to determine whether the EPB wake-up function is abnormal.

[0016] Therefore, the present invention adopts the above-mentioned FCT automatic detection system and detection method of the production line ECU, which has the following beneficial effects: 1. Optimize the test process: Use automated FCT testing equipment, and use the test process pre-compiled by the software to perform large-scale testing with high precision and low time; 2. High maintainability: The hardware system and software system of the automated FCT testing equipment are independently developed based on the modular test framework, which is convenient for later maintenance of the equipment or addition and deletion of test items. Especially for mass production, if a problem occurs in one of the items, the problem point can be accurately located and maintenance can be carried out quickly; 3. Save labor costs: After the automated FCT testing equipment is tested, no human intervention is required during operation, the test results can be fed back in real time, and the product test information can be traced; 4. Wide test coverage: The professional testing equipment and test needle bed used by the automated FCT testing equipment can reach an accuracy of 0.5 mm, maximizing the detection of points that need to be tested; 5. Forming scale effect: Automated FCT testing equipment can be used to test large-scale mass-produced ECUs, forming a closed loop for the entire production.

[0017] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 An exploded diagram of an FCT automated detection system for a production line ECU according to the present invention; Figure 2 This is a functional block diagram of an FCT automated detection system for a production line ECU of the present invention; Figure 3 The present invention is a flow chart of a detection method of an FCT automatic detection system for a production line ECU.

[0019] Reference numerals 1. Press down cylinder; 2. Buffer elastic pad; 3. Rivet top plate; 4. Change pad; 5. Rivet bottom plate; 6. Test needle bed; 7. Infrared sensor; 8. Linear slide; 9. Translation cylinder; 10. Positioning tooling; 11. Positioning column; 12. Support frame; 13. Joint bumper; 14. Limit block; 15. Proximity sensor. DETAILED DESCRIPTION

[0020] In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the invented product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of the present invention, it should also be noted that, unless otherwise clearly specified and limited, the terms "setting", "installation", and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] The embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0022] like Figure 1 and Figure 2As shown, an FCT automatic detection system for a production line ECU includes an industrial computer, a test unit, an execution unit, a programmable power supply and an FCT detection device. The FCT detection device includes a translation test bench, an ECU to be tested positioned and connected to the translation test bench, and a lifting test mechanism arranged directly above the ECU to be tested. The lifting test mechanism includes a pressing unit and a test needle bed 6 arranged at the bottom output end of the pressing unit. The industrial computer is connected to the PCBA board of the ECU to be tested via the test unit, the execution unit and the test needle bed 6 in sequence. The ECU to be tested is also connected to the industrial computer via a CAN bus and a programmable power supply, respectively.

[0023] The execution unit includes an EPB motor, a solenoid valve coil, a switch test assembly, a wheel speed sensor, a pressure sensor, a displacement sensor, and an indicator light assembly; the test unit includes a data acquisition card, an electronic load, and a wheel speed simulation card; the data acquisition card is connected to the solenoid valve coil, the switch test assembly, the indicator light assembly, the pressure sensor, and the displacement sensor, respectively, and is used to collect the output signals of the solenoid valve coil, the switch test assembly, the indicator light assembly, the pressure sensor, and the displacement sensor; the electronic load is connected to the EPB motor, and is used to drive the EPB motor to simulate operation according to the set mode; the wheel speed simulation card is connected to the wheel speed sensor, and is used to drive the wheel speed sensor to simulate the wheel speed. The wheel speed simulation card sends a simulated wheel speed signal through a fixed frequency (fixed frequency 800Hz) and a period (0.5ms), and the signal is received by the ECU to be tested. The industrial computer reads the wheel speed signal flag and the simulated wheel speed value transmitted to the CAN bus by the ECU to be tested, and the wheel speed test result can be judged by combining the sent signal, that is, if the CAN bus feedback signal and the frequency sent by the wheel speed board simulation card are the same and the CAN flag is 1, the result is normal, otherwise the result is abnormal.

[0024] In this embodiment, the wheel speed simulation board is fixed in the industrial control chassis through the PCIE interface.

[0025] The switch test component includes an AVH switch, an ESC switch, a HID switch, a BLS switch and an FLS switch; the indicator light component includes an EPB indicator light, an AVH indicator light and a HID indicator light.

[0026] The translation test bench includes a linear slide rail 8 fixed on the workbench, a positioning fixture 10 slidably set on the linear slide rail 8, the ECU to be tested is installed on the positioning fixture 10 via a positioning column 11, and the positioning fixture 10 is also connected to a translation cylinder 9 installed on the workbench; an infrared sensor 7 is arranged on the linear slide rail 8 and facing the positioning fixture 10, the infrared sensor 7 is connected to the PLC, the PLC is connected to the downward pressure cylinder 1, and is used to detect whether there is an ECU to be tested on the positioning fixture 10; a proximity sensor 15 is arranged on the linear slide rail 8 and facing the positioning fixture 10, the proximity sensor 15 is connected to the PLC, and the PLC is connected to the translation cylinder 9, and is used to detect whether the positioning fixture 10 is in place.

[0027] The pressing unit includes a pressing cylinder 1 fixed on the workbench via a support frame 12 and a test needle bed 6 arranged at the bottom output end of the pressing cylinder 1 via a limiting assembly; the limiting assembly includes a riveting top plate 3 at the bottom end of the pressing cylinder 1, a mold changing pad 4 arranged below the riveting top plate 3, and a riveting bottom plate 5 fixed to the bottom end of the mold changing pad 4, the top end of the mold changing pad 4 is fixedly connected to the bottom end of the joint collision block 13, the top end of the joint collision block 13 is vertically slidably connected to the riveting top plate 3, a limiting block 14 is arranged on the riveting top plate 3 and aligned with the top end of the joint collision block 13, and a vertical limiting margin is left between the limiting block 14 and the joint collision block 13; the mold changing pad 4 is fixedly connected to the top end of the test needle bed 6 via a mold changing fixed plate and a mold changing sliding block in turn, and the bottom end of the test needle bed 6 passes through the riveting bottom plate 5; the top end of the test needle bed 6 is also assembled with a pin and a pin fixing block and a mold changing pad 4 in turn.

[0028] A buffer elastic pad 2 is also arranged between the bottom output end of the downward pressure cylinder 1 and the riveting top plate 3 .

[0029] An infrared two-dimensional code scanner is provided at the input end of the infrared linear slide rail 8, and a two-dimensional code is provided on the side of the ECU to be tested facing the infrared two-dimensional code scanner. The infrared two-dimensional code scanner is connected to the PLC and is used to scan the two-dimensional code on the ECU to be tested through the infrared two-dimensional code scanner to form traceability information.

[0030] like Figure 3 As shown, the detection method of the FCT automatic detection system of the production line ECU includes the following steps: S1. At the input end of the linear guide rail 8, the ECU to be tested is mounted on the positioning fixture 10 using the positioning column 11; S2, start the translation cylinder 9, which drives the ECU to be tested to move along the linear slide rail 8 until the infrared sensor 7 detects that the ECU to be tested exists on the positioning fixture 10, and the proximity sensor 15 detects a signal of being in place, then the translation cylinder 9 stops moving and starts the pressing cylinder 1; In step S2, during the movement of the positioning fixture 10 along the linear slide rail 8, the infrared QR code scanner is used to scan the QR code on the ECU to be tested, obtain the traceability information, and upload the traceability information to the PLC. In this embodiment, the content scanned by the PLC is the product serial number, and then the PLC returns the scanned product serial number to the test software of the industrial computer. The test software receives this serial number, records it, and displays it on the test interface; and uploads it to the MES through this serial number to form a traceability code.

[0031] S3, the downward pressure cylinder 1 drives the test needle bed 6 downward until the joint collision block 13 presses against the limit block 14 to prevent the downward pressure cylinder 1 from moving downward. At this time, the probe on the test needle bed 6 is inserted into the PCBA board of the ECU to be tested; S4, start the industrial computer to simulate multiple working conditions, collect the feedback signals of the ECU under test under each working condition, and detect the performance of the ECU under test according to the feedback signals; The simulation of multiple working conditions in step S4 includes: Normal voltage test: detect whether the normal voltage of the test target point is 5V and the switch state of the indicator light component through the probe on the test needle bed 6 and the CAN message respectively; Wheel speed test: read the frequency and period sent by the wheel speed simulation card. If the frequency is 800Hz, it is judged as normal; if the frequency is 1200Hz, it is judged as dynamic; Test of the solenoid valve coil: open the solenoid valve coil with a 50% PWM duty cycle, and read the current value on the programmable power supply. At the same time, read the CAN message flag to determine whether the solenoid valve coil is open. After the test, close the solenoid valve coil and restore the flag. Pressure sensor test: Send a 70% PWM duty cycle test signal to the pressure sensor, and read the flag bit through the CAN message to determine the working status of the pressure sensor; Displacement sensor test: Determine the working status of the displacement sensor by reading the voltage value of the programmable power supply corresponding to the displacement sensor point; EPB motor forward and reverse rotation test: Use the electronic load to simulate a constant resistance of 1R, read the electronic load current and CAN message flag, test the forward and reverse rotation of the EPB motor, and set the CAN message flag to 0 after the test; Power off the test, stop sending messages, and read the voltage of the test target point of the test needle bed 6; EPB wake-up test: After the power-off test, use the relay to switch the switch state, release it after 50ms, and read the CAN message after waiting for 100ms to determine whether the EPB wake-up function is abnormal.

[0032] S5. After the test is finished, the PLC controls the pressure cylinder 1 and the translation cylinder 9 to reset in sequence, and removes the ECU to be tested.

[0033] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. An FCT automated detection system for production line ECU, characterized by: It includes an industrial computer, a test unit, an execution unit, a programmable power supply and FCT detection equipment. The FCT detection equipment includes a translation test bench, an ECU to be tested positioned and connected to the translation test bench, and a lifting test mechanism arranged directly above the ECU to be tested. The lifting test mechanism includes a pressing unit and a test needle bed arranged at the bottom output end of the pressing unit. The industrial computer is connected to the PCBA board of the ECU to be tested via the test unit, the execution unit and the test needle bed in sequence. The ECU to be tested is also connected to the industrial computer via the CAN bus and the programmable power supply respectively.

2. The FCT automatic detection system for production line ECU according to claim 1 is characterized by: The execution unit includes an EPB motor, a solenoid valve coil, a switch test assembly, a wheel speed sensor, a pressure sensor, a displacement sensor, and an indicator light assembly; The test unit includes a data acquisition card, an electronic load and a wheel speed simulation card; The data acquisition card is respectively connected to the solenoid valve coil, the switch test assembly, the indicator light assembly, the pressure sensor, and the displacement sensor, and is used to collect output signals of the solenoid valve coil, the switch test assembly, the indicator light assembly, the pressure sensor, and the displacement sensor; The electronic load is connected to the EPB motor to drive the EPB motor to simulate operation according to the set mode; The wheel speed simulation card is connected to the wheel speed sensor and is used to drive the wheel speed sensor to simulate the wheel speed.

3. The FCT automatic detection system for production line ECU according to claim 2 is characterized by: The switch test components include AVH switch, ESC switch, HID switch, BLS switch and FLS switch; The indicator light assembly includes an EPB indicator light, an AVH indicator light and a HID indicator light.

4. The FCT automatic detection system for production line ECU according to claim 3 is characterized by: The translation test bench includes a linear slide fixed on the workbench and a positioning fixture slidably arranged on the linear slide. The ECU to be tested is installed on the positioning fixture via a positioning column. The positioning fixture is also connected to a translation cylinder installed on the workbench. An infrared sensor is arranged on the linear slide rail and facing the positioning fixture. The infrared sensor is connected to the PLC, and the PLC is connected to the downward pressure cylinder to detect whether there is an ECU to be tested on the positioning fixture. A proximity sensor is arranged on the linear slide rail and facing the positioning tooling. The proximity sensor is connected to the PLC, and the PLC is connected to the translation cylinder to detect whether the positioning tooling is in place.

5. The FCT automatic detection system for production line ECU according to claim 4 is characterized by: The pressing unit comprises a pressing cylinder fixed on the workbench via a support frame and a test needle bed arranged at the output end of the bottom of the pressing cylinder via a limit assembly; The limiting assembly includes a riveted top plate at the bottom end of the pressing cylinder, a mold changing pad arranged below the riveted top plate, and a riveted bottom plate fixed to the bottom end of the mold changing pad. The top end of the mold changing pad is fixedly connected to the bottom end of the joint bumping block, and the top end of the joint bumping block is vertically slidably connected to the riveted top plate. A limiting block is arranged on the riveted top plate and aligned with the top end of the joint bumping block, and a vertical limiting margin is left between the limiting block and the joint bumping block. The mold-changing pad is fixedly connected to the top of the test needle bed through the mold-changing fixed plate and the mold-changing sliding block in sequence, and the bottom of the test needle bed passes through the riveting bottom plate; The top of the test needle bed is also assembled and connected with a latch, a latch fixing block and a change-type cushion block in sequence.

6. The FCT automatic detection system for production line ECU according to claim 5 is characterized by: A buffer elastic pad is also arranged between the bottom output end of the downward pressure cylinder and the riveting top plate.

7. The FCT automatic detection system for production line ECU according to claim 6 is characterized by: An infrared two-dimensional code scanner is provided at the input end of the infrared linear slide rail, a two-dimensional code is provided on the side of the ECU to be tested facing the infrared two-dimensional code scanner, and the infrared two-dimensional code scanner is connected to the PLC to scan the two-dimensional code on the ECU to be tested through the infrared two-dimensional code scanner to form traceability information.

8. The detection method of the FCT automatic detection system of the production line ECU as described in claim 7, characterized in that: The following steps are involved: S1. At the input end of the linear slide rail, use the positioning column to install the ECU to be tested on the positioning fixture; S2. Start the translation cylinder, which drives the ECU to be tested to move along the linear slide rail until the infrared sensor detects that the ECU to be tested exists on the positioning fixture and the proximity sensor detects an in-position signal. The translation cylinder stops moving and starts the pressing cylinder. S3, the downward pressure cylinder drives the test needle bed downward until the joint collision block hits the limit block to prevent the downward pressure cylinder from moving downward. At this time, the probe on the test needle bed is inserted into the PCBA board of the ECU to be tested; S4, start the industrial computer to simulate multiple working conditions, collect the feedback signal of the ECU under test under each working condition, and detect the performance of the ECU under test according to the feedback signal; S5. After the test is finished, the PLC controls the downward pressure cylinder and the translation cylinder to reset in sequence, and removes the ECU to be tested.

9. The detection method of the FCT automatic detection system of the production line ECU according to claim 8 is characterized by: In step S2, while the positioning tool moves along the linear slide rail, the two-dimensional code on the ECU to be tested is scanned by an infrared two-dimensional code scanner to obtain traceability information, and the traceability information is uploaded to the PLC.

10. The detection method of the FCT automatic detection system of the production line ECU according to claim 8, characterized in that: The simulation of multiple working conditions in step S4 includes: Normal voltage test: Use the probe on the test needle bed and the CAN message to detect whether the normal voltage of the test target point is 5V and the switch status of the indicator light component; Wheel speed test: read the frequency and period sent by the wheel speed simulation card. If the frequency is 800Hz, it is judged as normal; if the frequency is 1200Hz, it is judged as dynamic; Test of the solenoid valve coil: open the solenoid valve coil with a 50% PWM duty cycle, and read the current value on the programmable power supply. At the same time, read the CAN message flag to determine whether the solenoid valve coil is open. After the test, close the solenoid valve coil and restore the flag. Pressure sensor test: Send a 70% PWM duty cycle test signal to the pressure sensor, and read the flag bit through the CAN message to determine the working status of the pressure sensor; Displacement sensor test: Determine the working status of the displacement sensor by reading the voltage value of the programmable power supply corresponding to the displacement sensor point; EPB motor forward and reverse rotation test: Use the electronic load to simulate a constant resistance of 1R, read the electronic load current and CAN message flag, test the forward and reverse rotation of the EPB motor, and set the CAN message flag to 0 after the test; Power off the test, stop sending messages, and read the voltage of the test target point of the test bed of nails; EPB wake-up test: After the power-off test, use the relay to switch the switch state, release it after 50ms, and read the CAN message after waiting for 100ms to determine whether the EPB wake-up function is abnormal.

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