Whole vehicle sensor electrical fault simulation device and method

Abstract

The invention discloses a whole vehicle sensor electrical fault simulation device and method, and relates to the field of whole vehicle sensor testing. A signal acquisition device is used for acquiring a signal output by a sensor during normal work; the computer is used for acquiring a signal waveform, determining a signal type and a working range, modifying the signal waveform according to the signal type and the working range, and controlling the signal generator to simulate a sensor fault signal by using the modified signal waveform; a sensor fault signal generated by the signal generator is sent to the trip computer by connecting the wire harness with the fault test box; the vehicle-mounted diagnosis system obtains a sensor fault signal through the trip computer, judges the working state of the sensor and determines a fault code; and the on-board diagnostic system diagnostic instrument verifies whether the monitoring function of the on-board diagnostic system on the sensor is normal or not according to the fault code determined by the on-board diagnostic system. According to the invention, the electrical fault of the sensor of the whole vehicle can be simulated without dismounting the sensor, and the function verification of the OBD system on the sensor is realized.

Description

Technical Field

[0001] The present application relates to the technical field of vehicle sensor testing, and in particular to a device and method for simulating electrical faults of vehicle sensors. Background Art

[0002] With the full implementation of the China VI emission standards for heavy-duty vehicles, on-board diagnostics (OBD) systems are playing a crucial role in vehicle emissions monitoring. Functional verification of the OBD system typically requires fault simulation to verify its proper functioning. Sensor signals are crucial parameters for engine operation; their normality and signal reliability directly determine engine performance. Therefore, sensor monitoring is a crucial component of OBD system functional verification.

[0003] In the existing test scheme, the OBD system functional verification of the sensor function can only test the open circuit and short circuit fault simulation. During the fault simulation test, the sensor line to be verified on the entire vehicle is disconnected or short-circuited from the connector to simulate the open circuit or short circuit of the sensor. When the fault is recovered, the sensor is restored to complete the OBD system's functional verification of the sensor monitoring. This method has the following disadvantages: 1. The sensor is installed compactly, and disassembly and assembly is time-consuming and laborious, and the sensor and circuit are easily damaged. 2. Due to the structure of the sensor, the functional verification of some sensors cannot be achieved. 3. There are many types of sensors, and disassembly and assembly requires extremely high engine expertise. 4. It can only simulate open circuit and short circuit faults, and it is difficult to simulate reasonable sensor faults.

[0004] In summary, how to simulate the electrical fault of the vehicle sensor without disassembling the sensor and realize the functional verification of the sensor by the OBD system has become an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this application is to provide a whole vehicle sensor electrical fault simulation device and method, which can simulate the whole vehicle sensor electrical fault without disassembling the sensor, and realize the OBD system to verify the function of the sensor.

[0006] To achieve the above objectives, this application provides the following solutions:

[0007] In a first aspect, the present application provides a vehicle sensor electrical fault simulation device, the vehicle sensor electrical fault simulation device comprising a wiring harness connection fault test box, a signal acquisition device, a computer, a signal generator, and an on-board diagnostic system diagnostic instrument;

[0008] The wiring harness connection fault test box is connected to the vehicle computer and the sensor in the original vehicle components respectively; the signal acquisition device is connected to the sensor and the computer respectively; the signal generator is connected to the wiring harness connection fault test box and the computer respectively; the on-board diagnostic system diagnostic instrument is connected to the on-board diagnostic system in the original vehicle components; the on-board diagnostic system is connected to the vehicle computer;

[0009] The signal acquisition device is used to collect normal signals and send the normal signals to the computer; the normal signal is the signal output by the sensor during normal operation; the computer is used to obtain the signal waveform of the normal signal, determine the signal type and working range of the normal signal, modify the signal waveform according to the signal type and the working range, and use the modified signal waveform to control the signal generator to simulate the sensor fault signal; the signal generator is used to generate a sensor fault signal under the control of the computer; the sensor fault signal generated by the signal generator is sent to the on-board computer through the wiring harness connection fault test box; the on-board diagnostic system judges the working status of the sensor through the sensor fault signal obtained by the on-board computer, and determines the fault code according to the working status of the sensor; the on-board diagnostic system diagnostic instrument verifies whether the on-board diagnostic system's monitoring function for the sensor is operating normally through the fault code determined by the on-board diagnostic system.

[0010] Optionally, the signal acquisition device has the functions of setting the sampling rate, displaying the signal waveform and storing the sampled data.

[0011] Optionally, the wiring harness connection fault test box separates the power line and signal line of the on-board computer from the sensor, wherein the power line is connected to the sensor, and the signal line is sequentially connected to the signal acquisition device, the computer and the signal generator.

[0012] Optionally, the signal type includes analog signals and digital signals.

[0013] Optionally, when the signal type is an analog signal, the operating range is a voltage or current operating interval; when the signal type is a digital signal, the operating range is a frequency range or a bandwidth.

[0014] Optionally, when the signal type is an analog signal, the computer modifies the signal waveform by adjusting the output voltage or current;

[0015] When the signal type is a digital signal, the computer modifies the signal waveform by adjusting the frequency or bandwidth of the digital signal.

[0016] Optionally, the signal output by the sensor during normal operation is acquired by the signal acquisition device after the engine is started and operates under specific operating conditions.

[0017] Optionally, the specific operating conditions include key power on and off, vehicle start idling, engine onboard diagnostic system cycle, and vehicle portable emission test system cycle.

[0018] Optionally, the signal generator is a SENT signal simulator or a sensor fault simulator.

[0019] In a second aspect, the present application provides a vehicle sensor electrical fault simulation method based on the vehicle sensor electrical fault simulation device; the vehicle sensor electrical fault simulation method includes:

[0020] Acquire a normal signal collected by a signal acquisition device; the normal signal is a signal output by a sensor in an original component of the vehicle when the sensor is working normally;

[0021] Acquire a signal waveform of the normal signal, and determine a signal type and an operating range of the normal signal;

[0022] modifying the signal waveform according to the signal type and the operating range;

[0023] The modified signal waveform is used to control the signal generator to simulate the sensor fault signal.

[0024] According to the specific embodiments provided in this application, this application has the following technical effects:

[0025] The present application provides a device and method for simulating electrical faults of whole-vehicle sensors, which collects signals output by sensors in original parts of the whole vehicle during normal operation through a signal acquisition device, obtains signal waveforms through a computer, determines signal type and working range, modifies signal waveforms according to signal type and working range, and uses the modified signal waveforms to control a signal generator to simulate sensor fault signals. The sensor fault signals generated by the signal generator are sent to a driving computer in original parts of the whole vehicle through a wiring harness connected to a fault test box. The on-board diagnostic system in original parts of the whole vehicle judges the working status of the sensor through the sensor fault signals obtained by the driving computer, and determines a fault code according to the working status of the sensor. The on-board diagnostic system diagnostic instrument verifies whether the on-board diagnostic system's monitoring function for the sensor is operating normally through the fault code determined by the on-board diagnostic system, thereby achieving the effect of simulating the electrical faults of whole-vehicle sensors by connecting the fault test box, signal acquisition device, computer, signal generator and on-board diagnostic system diagnostic instrument through a wiring harness without disassembling the sensor, thereby achieving the effect of functional verification of the sensor by the OBD system. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 A schematic diagram of the structure of a vehicle sensor electrical fault simulation device provided in one embodiment of the present application;

[0028] Figure 2 A flowchart of a method for simulating electrical faults in a vehicle sensor provided in one embodiment of the present application is provided. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0030] The purpose of this application is to provide a whole vehicle sensor electrical fault simulation device and method, which can simulate the whole vehicle sensor electrical fault without disassembling the sensor, and realize the OBD system to verify the function of the sensor.

[0031] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0032] like Figure 1 As shown, the present application provides a whole vehicle sensor electrical fault simulation device, which includes a wiring harness connection fault test box, a signal acquisition device, a computer, a signal generator and an on-board diagnostic system diagnostic instrument.

[0033] The wiring harness connection fault test box is connected to the on-board computer and the sensors in the original components of the vehicle respectively; the signal acquisition device is connected to the sensor and the computer respectively; the signal generator is connected to the wiring harness connection fault test box and the computer respectively; the on-board diagnostic system diagnostic instrument is connected to the on-board diagnostic system in the original components of the vehicle; and the on-board diagnostic system is connected to the on-board computer. Figure 1 The dotted box represents the original parts of the vehicle. Figure 1 The Electronic Control Unit (ECU) is the driving computer in the original parts of the vehicle. Figure 1The on-board diagnostic system (OBD system) is an on-board diagnostic system in the original components of the vehicle. Figure 1 A mid-range sensor (a general term for various types of sensors on a vehicle) is one of the vehicle's original components. The wiring harness fault test box separates the power and signal cables from the onboard computer and the sensors. The power cables connect to the sensors, while the signal cables are sequentially routed to the signal acquisition device, computer, and signal generator.

[0034] The signal acquisition device is used to collect normal signals and send them to the computer; the normal signal is the signal output by the sensor when it is working normally. Among them, the signal output by the sensor when it is working normally is collected by the signal acquisition device after starting the engine and running specific working conditions. Specific working conditions include key power on and off, vehicle start idling, engine on-board diagnostic system cycle, and vehicle portable emission measurement system (PEMS) cycle. The signal acquisition device has the functions of setting the sampling rate, displaying the signal waveform, and storing the sampled data. The signal generator is a SENT signal simulator or a sensor fault simulator.

[0035] The computer is used to obtain the waveform of a normal signal, determine the signal type and operating range of the normal signal, modify the signal waveform based on the signal type and operating range, and use the modified signal waveform to control a signal generator to simulate a sensor fault signal. Signal types include analog and digital signals. When the signal type is analog, the operating range is the voltage or current operating range; when the signal type is digital, the operating range is the frequency range or bandwidth. When the signal type is analog, the computer modifies the signal waveform by adjusting the output voltage or current; when the signal type is digital, the computer modifies the signal waveform by adjusting the frequency or bandwidth of the digital signal.

[0036] The signal generator is used to generate a sensor fault signal under the control of a computer; the sensor fault signal generated by the signal generator is sent to the on-board computer via a wiring harness connected to a fault test box.

[0037] The on-board diagnostic system obtains the sensor fault signal through the on-board computer, determines the sensor working status, and determines the fault code based on the sensor working status.

[0038] The on-board diagnostic system diagnostic instrument verifies whether the on-board diagnostic system's monitoring function for the sensor is operating normally through the fault code determined by the on-board diagnostic system.

[0039] The technical solution of this application is described below with a specific embodiment:

[0040] The device for simulating electrical faults in vehicle sensors provided in this application utilizes a signal generator to simulate sensor fault signals and feed them back to the vehicle's ECU, verifying the vehicle's OBD system monitoring function. The device for simulating electrical faults in vehicle sensors provided in this application includes a wiring harness connection fault test box (i.e., a BOB breakout box), a signal acquisition device, a computer, a signal generator, and an OBD diagnostic instrument.

[0041] Among them, the junction box (i.e., BOB junction box) is directly connected in series to the ECU circuit and can distribute all circuit signals in the ECU circuit.

[0042] The signal acquisition device can collect signals from sensors and has functions such as setting sampling rate, displaying signal waveform and storing sampling data.

[0043] The computer has the ability to select and read the signal waveform files collected by the signal acquisition device, identify the signal type (i.e., signal type) and operating range, modify the collected signal waveform, and control the signal generator to produce the target signal (the computer sends the modified signal waveform to the signal generator, which then generates the target signal based on the modified signal waveform). The computer modifies the collected signal waveform by adjusting the output voltage or current, or the frequency or bandwidth of the digital signal. The target signal is the sensor fault signal.

[0044] The signal generator can generate analog signals and digital signals (the signal generator can simulate both analog signals and digital signals). According to the computer settings, it generates the required target signal and outputs it to the BOB junction box.

[0045] The OBD diagnostic instrument can read the vehicle's OBD system information and monitor vehicle fault reporting.

[0046] The process of simulating the electrical fault of the vehicle sensor provided by this application and implementing the functional verification of the sensor by the OBD system is as follows:

[0047] 1. Connect the BOB junction box in series to the ECU circuit, find the signal channel of the corresponding sensor according to the circuit diagram, and connect it to the signal simulator (i.e. signal generator) through the BOB junction box.

[0048] 2. Start the engine and run it under specific operating conditions (different sensor fault monitoring conditions are different and are related to the company's definition. Common monitoring conditions include: key power on and off, vehicle start idling, engine OBD cycle, vehicle PEMS cycle, etc.). The sensor output signal is collected through the signal acquisition device and fed back to the computer.

[0049] The signal acquisition device may be an oscilloscope, such as PicoScope series products.

[0050] 3. The computer receives feedback from the signal acquisition device, determines the signal type and operating range, and controls the signal generator to simulate the target sensor signal as required.

[0051] Signal types include analog and digital signals. For analog signals, the operating range refers to the operating range of physical quantities such as voltage and current. This prevents the voltage and current of the signal generator's output signal from exceeding the normal operating range and causing damage to the vehicle's ECU. For digital signals, the operating range refers to parameters such as frequency range and bandwidth.

[0052] The signal generator is controlled to simulate the target sensor signal according to the requirements, that is, the sensor fault signal is simulated according to the requirements. The requirements include: (1) the normal analog signal is a continuously fluctuating voltage or current signal. The fault simulation can output a fixed voltage or current signal to simulate an unreasonable sensor signal fault, or it can output high or low voltage or current to simulate an open or short circuit fault of the sensor. (2) The digital signal can adjust the frequency or bandwidth to simulate an unreasonable sensor signal fault.

[0053] 4. The signal generator simulates the target signal (i.e., simulates the sensor fault signal) and sends it to the ECU according to the computer instructions.

[0054] The signal generator may be an existing instrument such as a SENT signal simulator, a sensor fault simulator, etc. Both the SENT signal simulator and the sensor fault simulator are signal generator devices.

[0055] 5. Read the vehicle's OBD information through the OBD diagnostic instrument to verify whether the vehicle's OBD system can identify the sensor fault information.

[0056] The system operating logic of the vehicle sensor electrical fault simulation device provided in this application is as follows:

[0057] When performing OBD (on-board blinded device) function verification on various sensors, the power and signal cables between the ECU and the corresponding sensor are separated using a BOB junction box. The power cables are connected to the corresponding sensors, while the signal cables are sequentially connected to a signal acquisition device, a computer, and a signal generator. When the vehicle is powered on or started, the sensors operate normally and output normal signals to the signal acquisition device. The computer analyzes the collected sensor signals (collected sensor signals are also known as normal signals) to determine the signal type and operating range. At the same time, the target signal is set according to the requirements. The signal generator works and outputs according to the target signal set by the computer, and sends the output target signal to the ECU through the BOB junction box. The OBD system judges the working status of the sensor through the sensor signal obtained by the ECU (the sensor signal obtained by the ECU is the target signal). When the identified sensor signal (the identified sensor signal is the target signal) is abnormal, the OBD system will report the corresponding fault code. The fault code can be read by the OBD diagnostic instrument to verify the OBD system's functional monitoring of the sensor. The purpose of the test is to verify whether the fault code is consistent with the fault of the target signal set according to the requirements. What needs to be verified is: (1) whether there is a fault report after the sensor fails; (2) after the fault is reported, whether the fault information is consistent with the report.

[0058] The ECU processes sensor input data and adjusts engine operating parameters accordingly. The OBD system is a vehicle monitoring system that uses ECU data to monitor vehicle component data in real time to detect faults. The OBD system uses sensor signals received by the ECU to determine the sensor's operating status. Specifically, the OBD system uses these signals to determine sensor states such as open circuit, short circuit, or irrational signal. The OBD system determines the fault code based on the sensor's operating status. The OBD diagnostic instrument verifies the proper functioning of the OBD system's sensor monitoring function through fault code reading and data analysis.

[0059] Compared with the prior art, the advantages of this application are:

[0060] 1. Non-destructive, circuit faults can be simulated without plugging or unplugging sensors, avoiding damage to sensors and circuits.

[0061] 2. It has strong applicability and can be applied to the functional verification of most sensors.

[0062] 3. Simple and easy to install and operate, it can verify sensors in batches, saving time and resources.

[0063] 4. The simulation range is wide and the controllability is strong. The traditional method can only perform open circuit and short circuit verification. This application can generate any target signal as needed and is adjustable and controllable.

[0064] Based on the vehicle sensor electrical fault simulation device, the present application also provides a vehicle sensor electrical fault simulation method, such as Figure 2 As shown, the present application provides a vehicle sensor electrical fault simulation method, including:

[0065] Step S1: Acquire a normal signal collected by a signal acquisition device; the normal signal is a signal output by a sensor in an original component of the vehicle when it is working normally.

[0066] Step S2: Acquire the signal waveform of the normal signal and determine the signal type and operating range of the normal signal.

[0067] Step S3: Modify the signal waveform according to the signal type and working range.

[0068] Step S4: Using the modified signal waveform to control the signal generator to simulate the sensor fault signal.

[0069] This document uses specific examples to illustrate the principles and implementation methods of this application. The description of the above examples is only intended to help understand the method and core concept of this application. At the same time, for those skilled in the art, based on the concept of this application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A vehicle sensor electrical fault simulation device, characterized in that: The vehicle sensor electrical fault simulation device includes a wiring harness connection fault test box, a signal acquisition device, a computer, a signal generator and an on-board diagnostic system diagnostic instrument; The wiring harness connection fault test box is connected to the vehicle computer and the sensor in the original vehicle components respectively; the signal acquisition device is connected to the sensor and the computer respectively; the signal generator is connected to the wiring harness connection fault test box and the computer respectively; the on-board diagnostic system diagnostic instrument is connected to the on-board diagnostic system in the original vehicle components; the on-board diagnostic system is connected to the vehicle computer; The signal acquisition device is used to collect normal signals and send the normal signals to the computer; the normal signals are signals output by the sensor when it is working normally; The computer is used to obtain the signal waveform of the normal signal, determine the signal type and working range of the normal signal, modify the signal waveform according to the signal type and the working range, and use the modified signal waveform to control the signal generator to simulate the sensor fault signal; the signal generator is used to generate a sensor fault signal under the control of the computer; the sensor fault signal generated by the signal generator is sent to the on-board computer through the wiring harness connection fault test box; the on-board diagnostic system judges the sensor working status through the sensor fault signal obtained by the on-board computer, and determines the fault code according to the sensor working status; the on-board diagnostic system diagnostic instrument verifies whether the on-board diagnostic system's monitoring function for the sensor is operating normally through the fault code determined by the on-board diagnostic system.

2. The vehicle sensor electrical fault simulation device according to claim 1, characterized in that: The signal acquisition device has the functions of setting the sampling rate, displaying the signal waveform and storing the sampling data.

3. The vehicle sensor electrical fault simulation device according to claim 1, characterized in that: The wiring harness connection fault test box separates the power line and signal line of the on-board computer from the sensor, wherein the power line is connected to the sensor, and the signal line is sequentially connected to the signal acquisition device, the computer and the signal generator.

4. The vehicle sensor electrical fault simulation device according to claim 1, characterized in that: The signal types include analog signals and digital signals.

5. The vehicle sensor electrical fault simulation device according to claim 4, characterized in that: When the signal type is an analog signal, the operating range is a voltage or current operating range; when the signal type is a digital signal, the operating range is a frequency range or a bandwidth.

6. The vehicle sensor electrical fault simulation device according to claim 5, characterized in that: When the signal type is an analog signal, the computer modifies the signal waveform by adjusting the output voltage or current; When the signal type is a digital signal, the computer modifies the signal waveform by adjusting the frequency or bandwidth of the digital signal.

7. The vehicle sensor electrical fault simulation device according to claim 1, characterized in that: The signal output by the sensor during normal operation is acquired by the signal acquisition device after the engine is started and runs under specific operating conditions.

8. The vehicle sensor electrical fault simulation device according to claim 7, characterized in that: The specific operating conditions include key power on and off, vehicle start and idling, engine on-board diagnostic system cycle, and vehicle portable emission test system cycle.

9. The vehicle sensor electrical fault simulation device according to claim 1, characterized in that: The signal generator is a SENT signal simulator or a sensor fault simulator.

10. A method for simulating electrical faults of vehicle sensors, characterized in that: A vehicle sensor electrical fault simulation device according to any one of claims 1 to 9; The vehicle sensor electrical fault simulation method includes: Acquire a normal signal collected by a signal acquisition device; the normal signal is a signal output by a sensor in an original component of the vehicle when the sensor is working normally; Acquire a signal waveform of the normal signal, and determine a signal type and an operating range of the normal signal; modifying the signal waveform according to the signal type and the operating range; The modified signal waveform is used to control the signal generator to simulate the sensor fault signal.

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