Engine fault simulation system and method based on virtual bench

Abstract

The invention relates to the field of engine fault simulation, in particular to an engine fault simulation system and method based on a virtual rack, and the system comprises the VTB virtual rack which is in communication connection with a control upper computer, an ECU and real hardware. The VTB virtual bench comprises a real-time simulation machine used for operating an engine model; the multifunctional digital template card module is used for performing signal conversion between the real-time simulation machine and the ECU; the wire harness connection fault test box is connected between the multifunctional digital template card module and the ECU; the signal generation equipment is connected to the wire harness connection fault test box and is used for injecting a hardware fault signal to the ECU through the wire harness connection fault test box; the user driving data collected by the remote mobile terminal is used for configuring the model initial state of the real-time simulation machine and / or the control upper computer is used for generating a test working condition. And the dependence of a physical rack on an entity prototype and the high cost and the hardware damage risk caused by a destructive test are avoided.

Description

Technical Field

[0001] This application relates to the field of engine fault simulation, specifically to an engine fault simulation system and method based on a virtual test bench. Background Technology

[0002] In recent years, the technological iteration of commercial vehicle engines has accelerated significantly, and vehicle users have raised their requirements for engine lifespan. Logistics fleets generally require engines to achieve a no-overhaul mileage of 1 million kilometers to 2 million kilometers. Ensuring engine lifespan relies heavily on reliability testing of the engine as a whole and its components. Currently, mainstream reliability and lifespan testing is still conducted on traditional physical test benches.

[0003] As the complexity of engine systems continues to increase, traditional physical bench testing has revealed many problems in fault diagnosis and reliability verification: physical benches rely on physical prototypes, sensor deployment and destructive testing, the cost of reproducing a single fault is high, and extreme operating condition testing can easily cause overall hardware damage. Hidden faults such as mechanical wear and circuit interruption are difficult to control precisely when they occur, resulting in a low rate of reproducing occasional faults.

[0004] Therefore, there is an urgent need in this field for a testing solution that can overcome the above-mentioned technical bottlenecks, so as to significantly improve the accuracy, coverage and efficiency of fault testing while reducing costs and risks. Summary of the Invention

[0005] To address the above problems, this invention provides an engine fault simulation system and method based on a virtual test bench.

[0006] In a first aspect, the technical solution of the present invention provides an engine fault simulation system based on a virtual test bench, comprising: a control host computer, an ECU, real hardware, a VTB virtual test bench, a remote mobile terminal, and a signal generating device; The remote mobile terminal communicates with the host computer. The VTB virtual test bench is connected to the host control computer, ECU and real hardware respectively to simulate the behavior of real engine. The VTB virtual rack includes: A real-time simulator is used to run engine models; A multi-functional digital template card module is used for signal conversion between a real-time simulator and an ECU; The wiring harness connection fault test box is connected between the multi-functional digital template card module and the ECU; The signal generating device is connected to the wiring harness connection fault test box and is used to inject a hardware fault signal into the ECU through the wiring harness connection fault test box. The user driving data collected by the remote mobile terminal is used to configure the initial state of the model of the real-time simulator and / or used by the host computer to generate test conditions.

[0007] The signal generating device is used to inject electrical signals from the outside on demand; the host computer is used to configure and execute control strategies for the virtual test bench, issue control commands to the virtual test bench, and inject fault software; the real hardware is used for external human control of the behavior of the virtual test bench and execution of the issued commands; the ECU is used to receive fault information fed back by the virtual test bench and report it to the host computer, issue commands to the virtual test bench, and perform closed-loop control of the virtual test bench; the virtual test bench is used to simulate a real engine and receive, execute, and provide feedback on the commands from the ECU and the host computer.

[0008] As a further limitation of the technical solution of the present invention, the host computer is equipped with control software and configuration software. The configuration software is used to bind the I / O variables of the engine model to the physical channels of the multi-functional digital template card module. The control software is used to create a virtual instrument panel, change the model operating parameters in real time by mapping the variables of the engine model, and drive the multi-functional digital template card module to output signals to realize software injection of faults.

[0009] Through software configuration and variable mapping, engineers can quickly and flexibly configure and execute complex fault injection strategies in a graphical interface without modifying any hardware connections, greatly improving the convenience and efficiency of testing.

[0010] As a further limitation of the technical solution of the present invention, the control software integrates a signal generator module. The signal generator module is used to add preset waveforms or import external data files to generate long-term test conditions, and bind the test conditions to the output channel of the multi-functional digital template card module to inject abnormal signals into the ECU at a specific time point to realize automatic fault injection.

[0011] The signal generator module can generate long-term test conditions containing complex fault sequences, realizing the automation of fault injection and eliminating the dependence on real-time manual operation. It is particularly suitable for durability testing and the reproduction of complex fault scenarios.

[0012] As a further limitation of the technical solution of the present invention, the external data file includes user driving data file, driving test data file or bench test data file collected by the remote mobile terminal.

[0013] By using data from real vehicles, road tests, and bench tests to drive virtual benches, laboratory tests can accurately reproduce faults in various real-world scenarios, enhancing the reliability and persuasiveness of test results.

[0014] As a further limitation of the technical solution of the present invention, the engine model mounted on the real-time simulator is a high-precision model generated based on CRUISE M software according to the engine system structure, combustion formula, thermodynamic and aerodynamic formulas, which can perform real-time calculation and simulation of the in-cylinder combustion process of the engine.

[0015] Real-time models based on physical formulas (combustion, thermodynamics, etc.) can accurately simulate complex processes such as in-cylinder combustion in engines, making the output of the virtual test bench (such as torque and emission data) highly consistent with that of the real engine, thus ensuring the credibility of the test results.

[0016] As a further limitation of the technical solution of the present invention, the multi-functional digital module includes various types of boards, providing input and output capabilities for analog, digital, PWM, SENT, and CAN / LIN signals, and providing a configurable CAN bus system for the ECU.

[0017] Its rich I / O channels and configurable CAN bus enable it to seamlessly interface with various types of ECUs, sensors, and actuators, greatly expanding the system's versatility and applicability.

[0018] As a further limitation of the technical solution of the present invention, the ECU forms a closed-loop interaction with the host computer, the real-time simulator, the multi-functional digital template card and the real hardware; the ECU receives the engine status signal from the multi-functional digital template card module, calculates the actuator command, the real hardware and / or the multi-functional digital template card module respond to the command, and the real-time simulator calculates the new engine status based on the response result.

[0019] A complete control loop is formed between the ECU, the virtual engine (model), and the real hardware, which can realistically test the full performance of the ECU software in terms of dynamic response, fault diagnosis, and fault-tolerant control.

[0020] As a further limitation of the technical solution of the present invention, the actual hardware includes engine control unit hardware and execution unit hardware; the execution unit hardware includes one or more of the following: accelerator pedal, clutch, fuel injector, urea pump, urea nozzle solenoid valve, intake control valve, exhaust brake valve, turbocharger solenoid valve, HCI switch valve, HCI metering valve and fuel control valve.

[0021] Connecting real actuators (such as fuel injectors and various valves) to the system for testing can verify the interaction and fault response between the ECU and the actuator under real mechanical loads and electrical characteristics, resulting in more realistic and reliable test results.

[0022] Secondly, the present invention also provides an engine fault simulation method based on a virtual test bench, applied to the system described in the first aspect, the method comprising: A hardware fault signal is injected into the ECU via a signal generating device and a wiring harness connection fault test box connected between the multifunction digital template card module and the ECU; and / or By controlling the host computer, instructions are sent to the multi-functional digital template card module connected to the real-time simulator to achieve software fault injection.

[0023] By combining high-fidelity electrical simulation injected by hardware with flexible and programmable simulation injected by software, it can cover the full spectrum of fault types, from signal anomalies to controller logic errors, making the testing method comprehensive and efficient.

[0024] As a further limitation of the technical solution of the present invention, the software fault injection includes signal-level software injection and controller / actuator-level software injection; The signal-level software injection includes: modifying sensor signal values ​​inside the engine model, or binding predefined fault waveforms or data files to the output channel of the multi-functional digital template card module through the signal generator module to cover normal signals; The controller / actuator level software injection includes: modifying the state variables of the actuator in the engine model to simulate its failure, or sending erroneous CAN messages to the ECU through the CAN board of the multi-function digital template card module; The hardware fault injection step includes: at the wiring harness connection fault test box, using the signal generating device to hardwire or overwrite a specific electrical signal sent from the multi-function digital template card module to the ECU, in order to simulate a short circuit, open circuit, or signal interference in the circuit.

[0025] The simulation methods and levels (signal level / controller level) for different types of faults were clarified, enabling testers to accurately select the most appropriate injection strategy based on the test objectives, thereby improving the pertinence and scientific nature of the test.

[0026] As can be seen from the above technical solutions, this application has the following advantages: It uses a VTB virtual test bench to replace the physical engine for most tests, avoiding the dependence on physical prototypes and the high costs and hardware damage risks associated with destructive testing. Through the hardware injection path of the signal generation device via the BOB (Break-out Box, wiring harness connection fault test box) and the software injection capability of the control host computer, faults can be triggered at specific moments with millisecond-level precision, completely solving the problem of low reproducibility of latent faults such as mechanical wear and circuit interruptions in traditional methods. Utilizing real driving data collected by a remote mobile terminal to configure the model and generate test conditions allows the tests to truly reflect actual road conditions and reproduce sporadic faults that are difficult to design in a laboratory, greatly improving the coverage and effectiveness of the tests. Attached Figure Description

[0027] To more clearly illustrate the technical solution of this application, the accompanying drawings used in the description will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 A block diagram of a system provided in an embodiment of the present invention.

[0029] Figure 2 This is a schematic block diagram illustrating the functional implementation of the system provided in an embodiment of the present invention.

[0030] Figure 3 A flowchart illustrating a specific operational example of the simulation method provided in this embodiment of the invention. Detailed Implementation

[0031] To make the purpose, features, and advantages of this application more apparent and understandable, specific embodiments and accompanying drawings will be used to clearly and completely describe the technical solution protected by this application. Obviously, the embodiments described below are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0032] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this application and in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0033] like Figure 1As shown, this embodiment of the invention provides an engine fault simulation system based on a virtual test bench, including: a control host computer, an ECU, real hardware, a VTB virtual test bench, a remote mobile terminal, and a signal generating device; The remote mobile terminal communicates with the host computer. The VTB virtual test bench is connected to the host control computer, ECU and real hardware respectively to simulate the behavior of real engine. The VTB virtual rack includes: A real-time simulator is used to run engine models; A multi-functional digital template card module is used for signal conversion between a real-time simulator and an ECU; The wiring harness connection fault test box is connected between the multi-functional digital template card module and the ECU; The signal generating device is connected to the wiring harness connection fault test box and is used to inject a hardware fault signal into the ECU through the wiring harness connection fault test box. The user driving data collected by the remote mobile terminal is used to configure the initial state of the model of the real-time simulator and / or used by the host computer to generate test conditions.

[0034] In this embodiment of the invention, a remote mobile terminal is used to collect user driving data and transmit the data back to the control host computer terminal; a signal generating device is used to inject electrical signals from the outside as needed; the control host computer is used to configure and execute control strategies for the virtual test bench, issue control commands to the virtual test bench, and inject fault software; the real hardware includes an engine control unit and an execution unit, used to perform external human control of the virtual test bench behavior and execute the issued commands; the ECU is used to receive fault information fed back by the virtual test bench and report it to the control host computer, and issue commands to the virtual test bench to perform closed-loop control of the virtual test bench; the virtual test bench is used to simulate a real engine and receive, execute, and provide feedback on the commands from the ECU and the control host computer.

[0035] The VTB virtual test bench includes a real-time simulator, a multi-functional digital module card, and a BOB (Break-out Box) for wiring harness connection fault testing. The real-time simulator is equipped with a high-precision, detailed model of the engine and aftertreatment system. Based on real-world engine test bench data and combustion formulas, the model performs real-time calculations and simulations of the engine's in-cylinder combustion process, deriving engine torque and emission data to simulate real engine behavior. The multi-functional digital module card contains numerous multi-functional, software-configurable I / O channels, providing digital and analog input / output, such as voltage signals, current signals, PWM / PFM waveform signals, and SENT signals. It can output corresponding signals according to commands and directly simulate engine signals such as vehicle speed signals. The BOB provides a connection between the ECU and the board, facilitating independent extraction of each signal and enabling individual, precise fault injection through signal generation devices for hardware fault injection.

[0036] The virtual test bench connects to the host computer, ECU, and physical hardware via external interfaces. These interfaces primarily include I / O interfaces, Ethernet interfaces, and CAN bus interfaces.

[0037] In this embodiment of the invention, the host computer is equipped with control software and configuration software. The configuration software is used to bind the I / O variables of the engine model to the physical channels of the multi-functional digital template card module. The control software is used to create a virtual instrument panel, change the model's operating parameters in real time by mapping the variables of the engine model, and drive the multi-functional digital template card module to output signals to achieve software injection of faults.

[0038] The control software integrates a signal generator module, which is used to add preset waveforms or import external data files to generate long-term test conditions and bind the test conditions to the output channel of the multi-functional digital template card module to inject abnormal signals into the ECU at specific time points to achieve automatic fault injection.

[0039] The external data files include user driving data files, driving test data files, or bench test data files collected by the remote mobile terminal.

[0040] The engine model mounted on the real-time simulator is a high-precision model generated based on CRUISE M software, according to the engine system structure, combustion formula, thermodynamic and aerodynamic formulas, and capable of real-time calculation and simulation of the engine's in-cylinder combustion process.

[0041] The multi-functional digital module includes various types of boards, providing input and output capabilities for analog, digital, PWM, SENT, and CAN / LIN signals, and providing a configurable CAN bus system for the ECU.

[0042] The ECU forms a closed-loop interaction with the host computer, real-time simulator, multi-function digital template card and real hardware; the ECU receives the engine status signal from the multi-function digital template card module, calculates the actuator command, the real hardware and / or the multi-function digital template card module respond to the command, and the real-time simulator calculates the new engine status based on the response result.

[0043] The actual hardware includes engine control unit hardware and execution unit hardware; the execution unit hardware includes one or more of the following: accelerator pedal, clutch, fuel injector, urea pump, urea nozzle solenoid valve, intake control valve, exhaust brake valve, turbocharger solenoid valve, HCI switch valve, HCI metering valve, and fuel control valve.

[0044] like Figure 2 As shown, engine failures mainly originate from damage or untimely response of engine components and onboard sensors. The engine ECU receives and judges the operating status of each part and makes corresponding adjustments by receiving electrical signals. Therefore, a multi-functional digital template card can be used as a medium for transmitting and receiving electrical signals to replace engine components and sensors with equivalents, thereby simulating and injecting all electrical faults.

[0045] The signal generator is a hardware-level signal simulator, which may include programmable resistor / voltage sources, relay switch arrays, signal delayers, etc. It can simulate sensor output drift through voltage drift, simulate execution unit open circuit through signal truncation, simulate sensor open circuit through applying a large resistor, simulate communication grounding disconnection through current discharge and parallel connection of a ground resistor, and simulate communication error frames through pulse interference. The signal generator is connected to the system via a BOB to achieve hardware signal injection. This method can simulate pure, model-independent electrical faults with extremely high fidelity, making it suitable for testing the electrical characteristics of ECU input interfaces and their performance under extreme electrical conditions.

[0046] BOB provides a dense, standardized interface board that physically connects all cables between ECU pins and digital form card channels. Its core value lies in signal accessibility, routing each signal to an easily measurable jack or terminal, allowing engineers to easily monitor any signal using tools such as oscilloscopes and multimeters. BOB provides the physical basis for hardware signal injection. Engineers can connect signal generators to BOB to directly and precisely modify or overwrite specific signals on the physical lines, simulating various line faults (such as short circuits and open circuits) without damaging any wiring harnesses.

[0047] Real hardware devices serve as physical participants in the overall system testing, including the accelerator pedal, clutch, fuel injectors, urea pump, urea heating solenoid valve, urea nozzle solenoid valve, intake control valve, exhaust brake valve, turbocharger solenoid valve, HCI switching valve, HCI metering valve, and fuel control valve. By physically altering the state of these hardware components to simulate functional failure, the interaction between the ECU and the real hardware can be tested, particularly to assess the effectiveness of the ECU's response strategies when real actuators experience mechanical failures.

[0048] The control host computer is a graphical interface through which engineers interact with the entire virtual test bench system. It is responsible for commanding, monitoring, and analyzing data throughout the testing process. It is equipped with the operating software dSpace Control Desk and the configuration software Configuration Desk. The Configuration Desk software can use the dSPACE RTI library to add I / O modules to the model that correspond to the actual physical board channels, bind these I / O modules to the specific channels of the hardware boards, and set parameters such as sampling rate, voltage range, and communication baud rate. In the Control Desk software, virtual instrument panels can be created, and the controls on the panel can be mapped to variables in the real-time model. The model's operating parameters can be changed in real time. Based on the results of logical operations, the model drives the underlying boards through the RTI interface to change their output states. Clutter signals can be input or the voltage / current state of actuators can be changed at specific times. The Control Desk software is integrated with a Signal Generator module, which can add preset operating conditions, such as constants, sine waves, PWM waves, etc. Complex signal sequences can also be imported from external sources (e.g., .xlsx, .mat, or DBC files, such as INCA software experimental records, data transmitted from onboard mobile terminals, etc.) to generate long-term operating conditions that directly replicate fault conditions during the entire driving or testing process. Initial waveforms, amplitudes, frequencies, and other parameters can be set in the operating conditions and defined as adjustable parameters, which can then be invoked using controls in the Control Desk software interface. Compared to inputting fault signals through software at specific times, the Signal Generator module can directly generate long-term operating conditions with fault information and run them directly, allowing you to set the fault information at specific time points.

[0049] The ECU is the test object of the system and also the control center of the system. It receives "sensor" signals from the board, calculates and outputs control commands to the "actuator" based on the internally stored control logic, MAP diagram and algorithm. The output of the ECU drives the virtual engine (model), and the response of the model is fed back to the ECU to form a complete control closed loop, which is used to test the dynamic control quality and stability of the ECU software.

[0050] The multi-functional digital module is a collection of multiple DS2680, DS2601, DS2621, DS2671, and DS2690 boards, providing input / output capabilities for all signal types required by the engine system, including analog, digital, PWM, SENT, and CAN / LIN signals. It provides all I / O channels required for hardware-in-the-loop operation, with most I / O channels having fixed functions—dedicated analog or digital channels—providing digital and analog input / output, such as voltage signals, current signals, PWM / PFM waveform signals, and SENT signals. It can output corresponding signals according to instructions and directly simulate engine signals such as vehicle speed signals, providing a freely configurable CAN bus system for the ECU. Simultaneously, the multi-functional digital module can measure ECU output signals and transmit the measured values ​​to a real-time processor. Signal measurements can be time-triggered or event-triggered, and execution can be triggered by voltage or current. The multi-functional digital template card module can convert the physical quantities calculated by the real-time simulator into electrical signals that the ECU can recognize. At the same time, it can accurately capture the actuator drive signals issued by the ECU and convert them into digital quantities to be transmitted to the real-time simulator. The multi-functional digital template card module is the direct executor of software signal injection. When the host computer issues a fault command, the card will output incorrect voltage, current or waveform signals to the ECU. At the same time, CAN and other bus cards can simulate other controllers in the vehicle network (such as TCU, BCM), send messages to the ECU, and also listen to the bus messages issued by the ECU.

[0051] The real-time simulator serves as the core of the system's dynamics, simulating a real engine. It utilizes model files generated by CRUISE M software based on real engine bench data, engine system structure, combustion formulas, and thermodynamic and aerodynamic equations. Based on initialization and boundary conditions, it performs real-time calculations of the compression and combustion processes, updates the in-cylinder state of each cylinder, and performs data looping and coupling. This allows for real-time calculation and simulation of the engine's in-cylinder combustion process, yielding engine torque and emission data. It receives actuator commands from the ECU, calculates the in-cylinder combustion process in microsecond-level steps, and outputs the engine's instantaneous state. The physical quantities calculated by the model provide a data source for subsequent conversion into electrical signals for the ECU. The engine model's basic state can be configured based on data recorded by the INCA and data from the onboard mobile terminal.

[0052] Meanwhile, this schematic diagram enables an engine fault simulation method based on a virtual test bench. The method includes signal-level fault injection and controller / actuator-level fault injection. Signal-level fault injection includes software signal injection and hardware signal injection, while controller / actuator-level fault injection includes software command injection and physical intervention injection.

[0053] The goal of signal-level fault injection is to simulate abnormal sensor signals or electrical faults in the wiring between the ECU and the actuator / sensor. It occurs at the signal level, without altering the physical behavior of the model or hardware, only changing the transmitted electrical signals. Specifically: Software signal injection modifies the real-time simulation model or control software, directly altering the sensor signal values ​​sent to the ECU within the model. For example, adding a "fault offset" or "fault switch" mapping at the sensor signal output location in the Control Desk control panel changes the process quantity. When a fault is enabled, the signal value calculated by the model is incremented by an offset or assigned an error value and sent to the ECU via the analog output channel of the digital template card to report the fault. Alternatively, predefined fault waveforms (such as sine waves simulating jitter, step signals simulating sudden changes) or fault data files (.xlsx, .mat) collected from real vehicles can be imported into the Control Desk's Signal Generator module. This module is directly bound to the digital template card's output channel, overriding the normal signals emitted by the model at specific points in time and injecting abnormal electrical signals into the ECU. For instance, forcing the engine speed signal to zero within the model and stopping the transmission of crankshaft pulses via the digital output channel of the digital template card simulates complete sensor failure; or generating a continuously low voltage signal through the Signal Generator to replace the normal nitrogen-oxygen sensor signal, deceiving the ECU into believing the air-fuel mixture is too lean.

[0054] Hardware signal injection does not alter the software model; instead, it physically modifies the signals sent from the digital module card to the ECU using an external signal generator at the BOB (Block Layout Board). This can be achieved by: disconnecting the cable between the analog / digital output channel of the digital module card and the ECU pins at the BOB; connecting the output of a signal generator (such as a programmable power supply or waveform generator) to this loop; and having the operator control the signal generator to output abnormal electrical signals (such as 5V high, 0V low, or noisy waveforms) directly to the corresponding pins on the ECU. For example, on the BOB, locating the TPS signal line connected to the ECU and injecting a 12V voltage using an external voltage source simulates a short circuit to the throttle position sensor; on the BOB, connecting the coolant temperature sensor signal line to ground (GND) via a switch, closing the switch, and having the ECU read a 0V signal, simulating a short circuit to ground to the coolant temperature sensor; or using a relay to quickly switch the signal line on the BOB to simulate intermittent open circuits in the wiring harness.

[0055] The goal of controller / actuator-level fault injection is to simulate actuator failure or abnormal behavior of the ECU. Its focus is on functional abnormalities of the motion execution unit or control unit. Specifically: Software instruction injection modifies the actuator state variables in the engine model using Control Desk, directly defining the behavior of virtual actuators. By modifying actuator characteristics within the engine model, the ECU issues normal drive commands, but the model feeds back the engine state to the ECU as the state after actuator failure, thus reporting a fault. Alternatively, it simulates erroneous bus commands from the controller via the CAN board of a multifunction digital module card, directly sending erroneous CAN messages to the ECU controller. For example, triggering a fault in Control Desk causes the fuel injection quantity of a certain cylinder in the model to always be calculated as 0, simulating complete injector blockage in that cylinder. The ECU will detect engine misfire and torque reduction, simulating injector blockage. Online model modification can also cause the exhaust bypass valve opening to no longer respond to the ECU's vacuum control requests, i.e., the valve opening is always set to fully open, resulting in abnormal boost pressure, simulating turbocharger exhaust bypass valve jamming.

[0056] Physical intervention injection involves physically manipulating the real hardware connected to the system to induce abnormal actions or states. This involves connecting a real actuator to the system and then forcibly changing its state through external means. For example, a real urea nozzle can be connected to the system and physically blocked during testing to observe how the ECU responds to injection failures; a real clutch pedal switch can be connected and its internal mechanism manually damaged so that it cannot be engaged even when the pedal is depressed, simulating mechanical switch failure, etc.

[0057] The various fault injection methods can be performed simultaneously, complementing each other without conflict.

[0058] Taking EGR system fault injection and fatigue testing as an example, Figure 3 This is a flowchart for a specific operational example.

[0059] S100: Acquire engine operating data from real vehicles, road tests, and bench tests; wherein the data includes engine operating parameters, sensor signals, and actuator status information; process the data and convert it into a standardized data format that can be recognized by the system's simulation model and test conditions.

[0060] In the specific implementation process, data on the user's driving conditions is acquired. Based on the data collected and transmitted from the remote mobile terminal, vehicle condition, load, gradient, air pressure, temperature, etc., are configured as basic parameters and imported into the real-time simulator. The time axis and fault data are exported as .xlsx files based on the recorded operation of each sensor and actuator. Data on driving test conditions is acquired, and the sensor .dat data recorded during the driving test is exported as .xlsx or .mat files. Data on bench test conditions is acquired, and similar to the driving test, fault data and sensor overcurrent or voltage changes over time are recorded using INCA and exported as .xlsx or .mat files.

[0061] S200. Based on the standardized data, construct one or more test conditions in the host computer; wherein, the methods for constructing test conditions include: Generate signal sequences based on preset waveform templates; and / or directly import the processed standardized data to reproduce real operation and fault sequences; The constructed test conditions are bound to the corresponding virtual sensor variables or virtual actuator variables in the VTB virtual test bench.

[0062] The specific process includes: creating several Signal Generators on the Control Desk platform; binding and matching the sensor variables in the model that have been paired with the board channels with the signal generators; adding operating conditions to the signal generators, which can be preset conditions such as constants, sine waves, and PWM waves, and inserting fault noise at the required time points; also importing .xlsx or .mat files externally to directly reproduce the fault conditions included in the entire driving or test process; selecting different Signal Generators to send preset or built-in waveforms of operating conditions to the sensors or actuators simulated by different board channels, so that the sensor or actuator operates in the working state required by the test; regardless of the waveform, its related parameters can be set in the properties, with a very high degree of freedom.

[0063] S300: Download the bound test conditions and engine model to the real-time simulator and start automated testing; during test execution, inject faults through one or more of the following methods: According to the preset fault sequence in the test conditions, the control host computer automatically triggers software fault injection; The host computer receives real-time input from the user, triggering a temporary software fault injection. Hardware fault injection is triggered by operating the signal generating device and connecting the fault test box via the BOB harness.

[0064] The signal generator, along with the engine and after-processing model, is downloaded to the real-time simulator. Depending on the specific requirements, it can simulate user driving conditions, driving test conditions, and bench test conditions, and automatically inject faults. During operation, faults can also be injected in real time through the Control Desk platform, or hardware-based fault injection can be performed through controllers, actuators, and BOBs to meet temporary testing needs. It can perform response tests of various actuators under different requirements and fault effects. At the same time, it can perform fatigue tests of specific sensors or actuators under long-term operation conditions under specific faults.

[0065] According to S100, data preparation and initial engine model setup were performed by downloading actual driving data of a heavy-duty truck from the cloud platform of the onboard mobile terminal. This data includes long-term driving information such as vehicle speed, engine load, ambient temperature, and altitude, reflecting real road loads and driving habits. During engine bench testing, INCA software was used to record complete engine data under standard cycles (e.g., WHTC). This includes high-precision time-series data such as engine speed, torque, intake air flow, EGR valve opening command and actual opening, EGR gas temperature, and nitrogen oxide sensor readings. The data was exported as .mat or .xlsx format files, containing data snippets of normal operating conditions and EGR faults encountered during experiments. Typical operating points from the remote mobile terminal data (such as engine speed and load during long-term cruising) were used as the model's initialization and boundary conditions, and downloaded and configured to the real-time simulator.

[0066] According to S200, several Signal Generators are created in the Control Desk platform. Sensor variables already paired with the board channels in the model are bound and matched with the signal generators. Operating conditions can be added to the signal generators; these can be preset conditions such as constants, sine waves, and PWM waves. Fault noise can be inserted at the required time points. .xlsx or .mat files can also be imported externally to directly reproduce fault conditions included in the entire driving or testing process. In Control Desk, a Signal Generator is created and bound to the EGR valve behavior command signal in the model. The data file containing the EGR valve's brief jamming fault recorded in INCA is imported into this signal generator, thus creating a driving condition that triggers EGR valve jamming at a specific time. Simultaneously, another Signal Generator is created and mapped to the EGR cooler efficiency model parameters. Processed remote driving data is imported to generate a long-term operating condition with a slow decline in EGR cooling efficiency, simulating the progressive failure of cooler fouling.

[0067] According to S300, the configured engine model and the operating conditions of the two signal generators were compiled and downloaded to the real-time simulator. The test was initiated, and the real-time simulator began running a high-fidelity model driven by INCA data. When the model reached a preset fault point, the Signal Generator injected a signal indicating that the EGR valve's actual opening was stuck at 30%. Simultaneously, the model received a software instruction to modify the EGR valve actuator's response model to "no response," meaning that regardless of the ECU's command, the actual opening of the virtual EGR valve would no longer change. ECU response: The ECU detected a significant deviation between the EGR valve command and the actual opening, and its internal diagnostic program should quickly detect the fault. Observe whether the ECU reports a diagnostic fault code (DTC) within seconds, illuminates the engine malfunction indicator lamp (MIL), and takes measures such as limiting engine torque and adjusting the fuel injection strategy. After execution, a real urea nozzle was connected as the actuator under test in the virtual test bench. A long-term endurance test lasting hundreds of hours was then initiated. During this period, the Signal Generator, bound to "EGR cooler efficiency," continuously and slowly reduces its efficiency value (e.g., linearly decreasing from 95% to 70%) to simulate the fouling process. The model responds to the decrease in EGR cooling efficiency leading to increased intake air temperature, calculating higher NOx emissions accordingly. Simultaneously, the ECU adopts more aggressive aftertreatment strategies, such as increasing urea injection frequency and volume. This instruction, via the drive channel of the multifunction digital template card, acts on the actual urea nozzle, ensuring that the nozzle operates at a load higher than normal for hundreds of hours. Regularly checking the electrical and mechanical properties of the urea nozzle and comparing its lifespan under fault conditions with that under normal conditions allows for the assessment of its fatigue durability under system failure cascading effects.

[0068] This invention also provides an engine fault simulation method based on a virtual test bench, applied to the system described in the above embodiments, the method comprising: A hardware fault signal is injected into the ECU via a signal generating device and a wiring harness connection fault test box connected between the multifunction digital template card module and the ECU; and / or By controlling the host computer, instructions are sent to the multi-functional digital template card module connected to the real-time simulator to achieve software fault injection.

[0069] The software fault injection includes signal-level software injection and controller / actuator-level software injection; The signal-level software injection includes: modifying sensor signal values ​​inside the engine model, or binding predefined fault waveforms or data files to the output channel of the multi-functional digital template card module through the signal generator module to cover normal signals; The controller / actuator level software injection includes: modifying the state variables of the actuator in the engine model to simulate its failure, or sending erroneous CAN messages to the ECU through the CAN board of the multi-function digital template card module; The hardware fault injection step includes: at the wiring harness connection fault test box, using the signal generating device to hardwire or overwrite a specific electrical signal sent from the multi-function digital template card module to the ECU, in order to simulate a short circuit, open circuit, or signal interference in the circuit.

[0070] The specific implementation process is as follows: Step 1: Hardware Fault Injection Implementation Process The purpose of this process is to simulate electrical faults in the wiring between the sensor and the ECU at a physical level with extremely high fidelity.

[0071] The operator first determines the sensor signals that need to be simulated based on the test requirements.

[0072] Subsequently, on the BOB wiring harness connection fault test box, the specific physical channel or terminal connecting the sensor signal (simulated output by the multi-function digital template card module) to the corresponding pin of the ECU was found.

[0073] The signal lines located above are physically disconnected on the BOB using jumpers or switches.

[0074] Connect the output of the signal generating device (e.g., programmable power supply, waveform generator, resistor box) to this broken loop via a wire. Connect the common terminal of the signal generating device to the system ground.

[0075] The operator controls the signal generating device to output a preset abnormal electrical signal, which is then directly applied to the corresponding pin of the ECU. Specific implementation methods include: Use a programmable power supply to inject a high voltage (such as 12V) to simulate a short circuit to the power supply, or set its output to 0V to simulate a short circuit to ground.

[0076] Keep the circuit open, or use a relay to switch on and off at high speed to simulate intermittent circuit breaks.

[0077] Use a waveform generator to inject a waveform with specific noise, glitches, or frequency anomalies, such as a sine wave, to cover the original normal signal.

[0078] When the ECU receives a tampered abnormal electrical signal, its internal circuitry and control logic will respond accordingly. Testers monitor whether the ECU reports the expected diagnostic fault codes and whether the virtual engine model exhibits the corresponding abnormal state by controlling a host computer.

[0079] Step 2: Software Fault Injection Implementation Process This process simulates faults by modifying models or control instructions at the software level, offering high flexibility and automation potential. It comprises two levels: A. Signal-level software injection The goal of this level is to simulate signal anomalies or drift in the sensor itself.

[0080] In the engine model running on a real-time simulator, the output values ​​of specific sensor signals can be directly modified. For example, in the Control Desk software, the engine speed signal variable can be located, and a "fault offset" mapping control can be added to it.

[0081] When the fault is enabled via the control, the normal speed value calculated by the model is added with a negative offset and then sent to the ECU through the analog output channel of the multi-function digital template card module, simulating the speed sensor misalignment.

[0082] The Signal Generator module of the Control Desk software in the host computer is used.

[0083] Bind the output of the Signal Generator module to a specific output channel of the multi-function digital template card module.

[0084] In Signal Generator, you can either select a preset waveform or directly import a .xlsx or .mat data file containing fault segments collected from a real vehicle.

[0085] When the test is running, the Signal Generator will overwrite the normal sensor signals emitted by the engine model with its configured fault signals at a set time point, thereby injecting an incorrect physical quantity information into the ECU.

[0086] B. Controller / Actuator Level Software Injection The goal of this level is to simulate actuator failure or internal logic errors within the ECU.

[0087] The Control Desk software allows modification of the characteristic parameters or state variables of virtual actuators in the engine model. For example, it allows online modification of the injector model for a specific cylinder to ensure that its injection quantity is always zero.

[0088] At this point, the normal fuel injection command issued by the ECU is still valid, but the engine status fed back to the ECU by the model is the state when that cylinder is not working, thus simulating the mechanical failure of the fuel injector blockage.

[0089] Commands can be sent to the CAN board of the multi-functional digital template card module via software scripts or Control Desk controls.

[0090] The CAN board will, according to instructions, simulate other nodes in the vehicle network (such as the transmission control unit TCU) and continuously or intermittently send erroneous CAN messages to the ECU.

[0091] After receiving these erroneous network messages, the ECU will make incorrect judgments and controls based on its internal logic, thereby testing the robustness of its network communication and its logical fault tolerance.

[0092] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An engine fault simulation system based on a virtual test bench, characterized in that, include: Control host computer, ECU, real hardware, VTB virtual test bench, remote mobile terminal and signal generation equipment; The remote mobile terminal communicates with the host computer. The VTB virtual test bench is connected to the host control computer, ECU and real hardware respectively to simulate the behavior of real engine. The VTB virtual rack includes: A real-time simulator is used to run engine models; A multi-functional digital template card module is used for signal conversion between a real-time simulator and an ECU; The wiring harness connection fault test box is connected between the multi-functional digital template card module and the ECU; The signal generating device is connected to the wiring harness connection fault test box and is used to inject a hardware fault signal into the ECU through the wiring harness connection fault test box. The user driving data collected by the remote mobile terminal is used to configure the initial state of the model of the real-time simulator and / or used by the host computer to generate test conditions.

2. The engine fault simulation system based on a virtual test bench according to claim 1, characterized in that, The host computer is equipped with control software and configuration software. The configuration software is used to bind the I / O variables of the engine model to the physical channels of the multi-functional digital template card module. The control software is used to create a virtual instrument panel, map the variables of the engine model to change the model's operating parameters in real time, and drive the multi-functional digital template card module to output signals to achieve software injection of faults.

3. The engine fault simulation system based on a virtual test bench according to claim 2, characterized in that, The control software integrates a signal generator module, which is used to add preset waveforms or import external data files to generate long-term test conditions and bind the test conditions to the output channel of the multi-functional digital template card module to inject abnormal signals into the ECU at specific time points to achieve automatic fault injection.

4. The engine fault simulation system based on a virtual test bench according to claim 3, characterized in that, The external data files include user driving data files, driving test data files, or bench test data files collected by the remote mobile terminal.

5. The engine fault simulation system based on a virtual test bench according to claim 4, characterized in that, The engine model mounted on the real-time simulator is a high-precision model generated based on CRUISE M software, according to the engine system structure, combustion formula, thermodynamic and aerodynamic formulas, and capable of real-time calculation and simulation of the engine's in-cylinder combustion process.

6. The engine fault simulation system based on a virtual test bench according to claim 5, characterized in that, The multi-functional digital module includes various types of boards, providing input and output capabilities for analog, digital, PWM, SENT, and CAN / LIN signals, and providing a configurable CAN bus system for the ECU.

7. The engine fault simulation system based on a virtual test bench according to claim 6, characterized in that, The ECU forms a closed-loop interaction with the host computer, real-time simulator, multi-function digital template card and real hardware; the ECU receives engine status signals from the multi-function digital template card module, calculates actuator commands, the real hardware and / or the multi-function digital template card module respond to the commands, and the real-time simulator calculates the new engine status based on the response results.

8. The engine fault simulation system based on a virtual test bench according to claim 7, characterized in that, The actual hardware includes engine control unit hardware and actuator hardware; the actuator hardware includes one or more of the following: accelerator pedal, clutch, fuel injector, urea pump, urea nozzle solenoid valve, intake control valve, exhaust brake valve, turbocharger solenoid valve, HCI switch valve, HCI metering valve, and fuel control valve.

9. A method for simulating engine faults based on a virtual test bench, applied to the system as described in any one of claims 1-8, characterized in that, The method includes: A hardware fault signal is injected into the ECU via a signal generating device and a wiring harness connection fault test box connected between the multifunction digital template card module and the ECU; and / or By controlling the host computer, instructions are sent to the multi-functional digital template card module connected to the real-time simulator to achieve software fault injection.

10. The engine fault simulation method based on a virtual test bench according to claim 9, characterized in that, The software fault injection includes signal-level software injection and controller / actuator-level software injection; The signal-level software injection includes: modifying sensor signal values ​​inside the engine model, or binding predefined fault waveforms or data files to the output channel of the multi-functional digital template card module through the signal generator module to cover normal signals; The controller / actuator level software injection includes: modifying the state variables of the actuator in the engine model to simulate its failure, or sending erroneous CAN messages to the ECU through the CAN board of the multi-function digital template card module; The hardware fault injection step includes: at the wiring harness connection fault test box, using the signal generating device to hardwire or overwrite a specific electrical signal sent from the multi-function digital template card module to the ECU, in order to simulate a short circuit, open circuit, or signal interference in the circuit.

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