Steering gear damage monitoring method and system of rear-wheel steering vehicle, vehicle and medium

Abstract

The invention discloses a steering gear damage monitoring method and system of a rear-wheel steering vehicle, the vehicle and a medium. The method comprises the following steps: acquiring vehicle motion data of a target vehicle; inputting the vehicle motion data into a vehicle dynamics model, and calculating to obtain a rear wheel steering parameter of the target vehicle in the vehicle dynamics model; and calculating a damage value of a rear wheel steering gear of the target vehicle according to the rear wheel steering parameters. According to the method, related motion state signals of the vehicle are collected, the size of the rear wheel turning angle, the rear wheel turning angle speed, the vehicle speed, the steering wheel turning angle, the lateral acceleration, the yaw velocity, the rear turning working state and the like of the user vehicle in the whole life cycle are monitored, and lateral force borne by rear wheels is calculated through a digital twinborn model of the vehicle; and meanwhile, according to the rear wheel rotation angle and the rear wheel rotation angle speed, the current rear-rotation actuator durability damage can be synchronously calculated. And when the damage risk is judged to exist after a certain damage threshold value is accumulated, the vehicle is controlled to give an alarm, and a driver is reminded to maintain and repair in time.

Description

Technical Field

[0001] The invention relates to the technical field of rear wheel steering gear damage monitoring, and in particular to a steering gear damage monitoring method, system, vehicle and medium for a rear wheel steering vehicle. Background Art

[0002] Rear-wheel steering is a vehicle steering control system, also known as four-wheel steering or all-wheel steering; currently, traditional cars in the domestic automobile market only have the front wheels for steering, while the rear wheels remain fixed. For vehicles equipped with a rear-wheel steering system, when the vehicle is turning, in addition to the front wheels providing steering force and steering direction for the vehicle, the rear-wheel steering device can also control the rear wheels to rotate to a certain steering angle, so that the rear wheels can also participate in steering, thereby providing better control performance and stability.

[0003] During the continuous operation of the rear wheel steering gear at the user end, the real-time change of external load may cause internal damage to the rear wheel steering gear, which will seriously affect driving safety. Therefore, it is very important to ensure the safety and reliability of the rear wheel steering gear during use.

[0004] However, the safety and reliability of the rear-wheel steering gear is currently guaranteed entirely through early design verification, and there is a lack of damage monitoring function for the rear-wheel steering gear during use. During the design verification phase of the vehicle, engineers usually design and verify the vehicle according to standard road spectra and standard working conditions; however, different users have different driving habits, and different vehicles have different daily driving conditions, which may lead to redundant or insufficient life design for the rear-wheel steering gear. On the one hand, redundant design life may lead to increased product costs, and on the other hand, insufficient design life may affect user driving safety. Summary of the invention

[0005] In view of this, an embodiment of the present invention provides a steering gear damage monitoring method, system, vehicle and medium for a rear-wheel steering vehicle.

[0006] A first aspect of the present invention discloses a method for monitoring damage of a steering gear of a rear-wheel steering vehicle, comprising the following steps: Obtaining vehicle motion data of a target vehicle; Inputting the vehicle motion data into a vehicle dynamics model, and calculating rear wheel steering parameters of the target vehicle in the vehicle dynamics model; The damage value of the rear wheel steering gear of the target vehicle is calculated according to the rear wheel steering parameters.

[0007] Furthermore, the vehicle motion data of the target vehicle includes at least rear wheel turning angle, rear wheel turning angle velocity, lateral acceleration, yaw angular velocity, steering wheel angle and vehicle speed; Wherein, the rear wheel steering angle and rear wheel steering speed are obtained through the rear wheel steering device of the target vehicle; The lateral acceleration and yaw angular velocity are obtained by an inertial measurement unit of the target vehicle; The steering wheel angle is obtained through a steering system of the target vehicle; The vehicle speed is obtained through an anti-lock braking system of the target vehicle.

[0008] Furthermore, the vehicle dynamics model is a digital twin model of the target vehicle; the vehicle dynamics model can receive vehicle motion data of the target vehicle in real time through a vehicle data interface, and update the vehicle dynamics model in real time according to the received vehicle motion data.

[0009] Furthermore, the step of inputting the vehicle motion data into a vehicle dynamics model and calculating the rear wheel steering parameters of the target vehicle in the vehicle dynamics model specifically includes the following steps: Establishing a data transmission relationship between the target vehicle and the vehicle dynamics model through the vehicle data interface; When the target vehicle generates vehicle motion data, the vehicle motion data is transmitted to the vehicle dynamics model in real time through the vehicle data interface; The vehicle motion data is applied to a vehicle dynamics model to perform rear wheel steering calculation to obtain rear wheel steering parameters of the target vehicle.

[0010] Furthermore, the rear wheel steering parameters include rear wheel slip angle and rear wheel lateral force; Wherein, the rear wheel slip angle is calculated by the rear wheel speed angle output by the vehicle dynamics model; The rear wheel lateral force is calculated by combining the rear wheel speed angle output by the vehicle dynamics model with the cornering stiffness of the rear wheel.

[0011] Further, the calculation of the damage value of the rear-rotating screw transmission mechanism model includes the following steps: Calculate the external load, active force and displacement of the rear wheel steering screw; According to the calculated external load size, main force size and displacement of the rear wheel steering screw, the damage value of the rear wheel steering screw transmission mechanism model is calculated.

[0012] Furthermore, the external load size of the rear wheel steering screw is calculated based on the hard point position, wheel center position, ground contact point position, steering rod offset distance of the target vehicle's rear wheel steering gear assembly and the rear wheel lateral force.

[0013] Furthermore, the magnitude of the active force of the rear wheel steering screw is calculated by the following formula: The active force on the lead screw applied by the motor is calculated based on the motor assist torque of the rear wheel steering and the transmission ratio at this time.

[0014] Furthermore, the displacement of the rear wheel steering screw is calculated based on the motor assist torque of the rear wheel steering gear assembly in the vehicle dynamics model and the transmission ratio of the target vehicle.

[0015] Further, the damage value of the rear wheel steering screw transmission mechanism model is calculated based on the calculated external load size, main force size and displacement of the rear wheel steering screw, which specifically includes the following steps: Inputting the external load magnitude, active force magnitude and displacement of the rear wheel steering screw into the rear wheel steering screw transmission mechanism model of the target vehicle to obtain the stress distribution of the rear wheel steering gear of the target vehicle; The life curve of the rear wheel steering gear of the target vehicle is obtained, and the accumulated damage of the rear wheel steering gear is calculated according to the stress distribution as the damage value of the rear wheel steering gear of the target vehicle.

[0016] Furthermore, the method further comprises the following steps: Setting damage thresholds; When the damage value of the rear wheel steering gear of the vehicle exceeds the set damage critical value, the rear wheel steering gear of the vehicle is controlled to stop working, and the vehicle is controlled to perform an alarm operation.

[0017] Furthermore, the alarm operation specifically includes the following steps: After the rear wheel steering operation is completed, stopping the movement of the rear wheel steering gear of the target vehicle; Sends rear-wheel steering warning information to the driver.

[0018] A second aspect of the present invention discloses a steering gear damage monitoring system for a rear-wheel steering vehicle, comprising a data acquisition module, a vehicle digital twin module, and a damage calculation module; The data acquisition module is used to obtain vehicle motion data of the target vehicle; The vehicle digital twin module is used to input the vehicle motion data into a vehicle dynamics model, and calculate the rear wheel steering parameters of the target vehicle in the vehicle dynamics model; The damage calculation module is used to calculate the damage value of the rear wheel steering gear of the target vehicle according to the rear wheel steering parameters.

[0019] The third aspect of the present invention discloses a vehicle, which is equipped with an on-board computer, which includes a processor, a memory, and computer program instructions stored in the memory and executable on the processor, and the processor implements the steering gear damage monitoring method for a rear-wheel steering vehicle when executing the computer program instructions.

[0020] A fourth aspect of the present invention discloses a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the steering gear damage monitoring method for a rear-wheel steering vehicle.

[0021] The present invention has the following beneficial effects: The present invention provides a steering gear damage monitoring method, system, vehicle and medium for a rear-wheel steering vehicle, which collects vehicle-related motion state signals, monitors the rear wheel steering angle, rear wheel steering angular velocity, vehicle speed, steering wheel angle, lateral acceleration, yaw angular velocity, rear steering working status, etc. of the user's vehicle throughout its life cycle, and calculates the lateral force on the rear wheel through the vehicle's digital twin model. At the same time, according to the rear wheel steering angle and rear wheel steering angular velocity, the current rear steering actuator durable damage can be calculated synchronously. The present invention can perform real-time damage prediction through big data monitoring and damage calculation strategies. When a certain damage threshold is accumulated and it is judged that there is a risk of damage, the vehicle is controlled to alarm and remind the driver to perform timely maintenance and repairs.

[0022] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The present invention is a flowchart of the basic steps of a method for monitoring damage of a steering gear of a rear-wheel steering vehicle according to an embodiment of the present invention.

[0024] Figure 2 It is a schematic diagram of vehicle motion data obtained according to an embodiment of the present invention.

[0025] Figure 3 It is a schematic diagram of the vehicle dynamics model used in the embodiment of the present invention.

[0026] Figure 4 It is a schematic diagram of a flow chart of obtaining rear wheel steering parameters of a target vehicle through a vehicle dynamics model in an embodiment of the present invention.

[0027] Figure 5 It is a schematic diagram of a flow chart of calculating the damage value of a rear wheel steering gear of a target vehicle according to an embodiment of the present invention.

[0028] Figure 6 It is a schematic diagram of the life curve of the rear wheel steering gear according to an embodiment of the present invention.

[0029] Figure 7 It is a schematic diagram of a damage criticality judgment process in a steering gear damage monitoring method for a rear-wheel steering vehicle according to an embodiment of the present invention.

[0030] Figure 8 The present invention is a schematic structural diagram of a steering gear damage monitoring system for a rear-wheel steering vehicle according to an embodiment of the present invention.

[0031] Fig. 9 The present invention is a schematic diagram of a vehicle structure.

[0032] Fig.10 It is a schematic diagram of the structure of a computer-readable storage medium of the present invention. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. At the same time, it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0034] Existing rear-wheel steering vehicles usually design and develop rear-wheel steering gears based on standard road spectra and standard road conditions, which can ensure that the vehicle can perform rear-wheel steering normally under common working conditions. However, when the vehicle is driven for a long time on extreme road conditions such as muddy, dusty or antifreeze, the rear-wheel steering gear may quickly accumulate damage; at the same time, different users have different driving habits and daily driving conditions, so the service life of the rear-wheel steering gear is difficult to effectively estimate during the design and development stage.

[0035] In order to overcome the above problems, a first embodiment of the present invention provides a steering gear damage monitoring method for a rear-wheel steering vehicle.

[0036] like Figure 1 As shown, the steering gear damage monitoring method for a rear-wheel steering vehicle provided in the first embodiment of the present invention comprises the following steps: S1. Obtain vehicle motion data of the target vehicle; S2. Inputting the vehicle motion data into the vehicle dynamics model, and calculating the rear wheel steering parameters of the target vehicle in the vehicle dynamics model; S3. Calculate the damage value of the rear wheel steering gear of the target vehicle according to the rear wheel steering parameters.

[0037] In the embodiment of the present invention, by collecting the vehicle motion data of the target vehicle and inputting the vehicle motion data into the vehicle dynamics model for simulation calculation, the rear wheel steering parameters generated by the rear wheel steering gear of the target vehicle when outputting these vehicle motion data can be obtained, and the damage value of the rear wheel steering gear of the target vehicle can be further calculated by the rear wheel steering parameters. The method of the embodiment of the present invention can effectively make up for the shortcomings of the life estimation of the rear wheel steering gear in the early design stage of the target vehicle, and synchronously and quantitatively calculate the current damage value when the rear wheel steering gear of the target vehicle is damaged, which plays an immediate prompt role in the durability estimation of the rear wheel steering gear.

[0038] Specifically, in step S1 of the embodiment of the present invention, by arranging multiple sensors on the target vehicle and collecting motion data of multiple modules of the target vehicle, vehicle driving data including rear wheel steering angle, rear wheel steering angular velocity, lateral acceleration, yaw angular velocity, steering wheel angle and vehicle driving speed can be obtained. For example, Figure 2 As shown in the figure, the rear wheel steering angle and rear wheel angular velocity can be obtained through the rear wheel steering gear of the target vehicle; the lateral acceleration and yaw angular velocity can be obtained through the inertial measurement unit of the target vehicle; the steering wheel angle is obtained through the steering system of the target vehicle; and the vehicle speed is obtained through the anti-lock braking system of the target vehicle. In some vehicles with a high degree of digitization, various vehicle motion data will be collected in the vehicle's controller area network (CAN), so the vehicle motion data of the target vehicle can also be directly connected to the vehicle's controller area network. After obtaining the vehicle motion data, the vehicle driving data is input into the vehicle dynamics model to simulate the motion of the target vehicle.

[0039] In some embodiments, in order to achieve better calculation results of the vehicle dynamics model, parameters such as road adhesion conditions and tire conditions may be obtained as vehicle motion data, and the corresponding road model and tire model may be calculated in the vehicle dynamics model.

[0040] like Figure 3 As shown, the vehicle dynamics model of the present invention is a digital twin model of the target vehicle. A digital twin model refers to a model that is obtained by digital twinning the design parameters of the target vehicle in a virtual space and can reflect the state and dynamic behavior of the target vehicle. When the digital twin model receives the vehicle motion data, it can twin the physical dynamic behavior of the target vehicle in the virtual space, thereby realizing real-time perception of the actual state and behavior of the target vehicle.

[0041] The digital twin model in the embodiment of the present invention has a unified vehicle data interface, which receives the vehicle motion data of the target vehicle in real time through the vehicle data interface and normalizes the data so that the vehicle motion data can be recognized by the vehicle dynamics model. Specifically, Figure 4 As shown, in step S2 of the embodiment of the present invention, the vehicle motion data is input into the vehicle dynamics model, and the rear wheel steering parameters of the target vehicle are calculated in the vehicle dynamics model, including the following steps: S2-1. Establish data transmission relationship between the target vehicle and the vehicle dynamics model through the vehicle data interface; S2-2. When the target vehicle generates vehicle motion data, the vehicle motion data is transmitted to the vehicle dynamics model in real time through the vehicle data interface; S2-3. Apply the vehicle motion data to the vehicle dynamics model to perform rear-wheel steering calculations to obtain rear-wheel steering parameters of the target vehicle.

[0042] In the embodiment of the present invention, the vehicle dynamics model is deployed in the cloud. After the target vehicle collects the vehicle motion data, the vehicle motion data is uploaded to the vehicle dynamics model through the vehicle data interface in the cloud. After the rear wheel steering calculation of the vehicle is completed in the cloud and the rear wheel steering parameters of the target vehicle are obtained, the rear wheel steering parameters are returned to the target vehicle for damage value calculation. The vehicle dynamics model deployed in the cloud can obtain timely technical maintenance from vehicle operation and maintenance personnel, and can also reduce the operating burden of the vehicle system and reduce the risk of downtime of the vehicle system. For some target vehicles with higher configurations, a mirror image of the vehicle dynamics model can also be deployed locally. When the Internet of Vehicles communication is abnormal or stuck, the rear wheel steering of the vehicle is calculated through the local mirror model to obtain the rear wheel steering parameters.

[0043] The rear wheel steering parameters output by the vehicle dynamics model in the embodiment of the present invention at least include the rear wheel sideslip angle and the rear wheel lateral force.

[0044] Specifically, the rear wheel slip angle is calculated by the rear wheel speed angle output by the vehicle dynamics model: ; in, is the rear wheel speed angle.

[0045] In the vehicle dynamics model, the rear wheel speed angle Calculated by the following formula: ; in is the longitudinal velocity calculated by the vehicle dynamics model, is the lateral velocity calculated by the vehicle dynamics model, is the distance from the rear wheel to the center of mass of the vehicle, is the yaw rate of the vehicle; and Design parameters for the vehicle.

[0046] The rear wheel lateral force is calculated by combining the rear wheel velocity angle output by the vehicle dynamics model with the cornering stiffness of the rear wheel of the vehicle: ; in, is the cornering stiffness of the rear wheel and is the design parameter of the vehicle.

[0047] After obtaining the rear wheel steering parameters, the embodiment of the present invention further calculates the damage value of the rear wheel steering gear of the target vehicle through the rear screw transmission mechanism model.

[0048] The damage calculation process of step S3 is as follows: Figure 5 As shown, the specific steps include: S3-1. Calculate the external load, active force and displacement of the rear wheel steering screw; S3-2. According to the calculated external load size, main force size and displacement of the rear wheel steering screw, the damage value of the rear wheel steering screw transmission mechanism model is calculated.

[0049] Among them, the external load of the rear-wheel steering screw refers to the load generated by external forces such as vehicle weight and road friction acting on the rear-wheel steering screw of the vehicle. According to the hard point position, wheel center position, ground contact point position, steering rod offset distance of the rear-wheel steering gear assembly in the target vehicle design parameters combined with the rear wheel lateral force output by the vehicle dynamics model, the external load of the rear-wheel steering screw can be calculated. The active force of the rear-wheel steering screw refers to the steering force applied by the target vehicle to the rear-wheel steering screw. The active force applied by the motor on the screw can be calculated through the motor assist torque and transmission ratio of the rear-wheel steering. The displacement of the rear-wheel steering screw refers to the displacement of the steering screw controlled by the target vehicle for rear-wheel steering, which is calculated by the number of revolutions of the rear-wheel steering gear motor combined with the transmission ratio.

[0050] In step S3-2, the embodiment of the present invention uses the rear screw transmission mechanism model to calculate the damage of the rear wheel steering gear of the target vehicle. The rear screw transmission mechanism model is a model that simulates the rear wheel steering gear of the target vehicle, including the rear wheel of the vehicle, the rear screw, the motor and various connecting parts. When the vehicle performs rear wheel steering, the main force and external force of the rear wheel steering will be applied to the rear screw, thereby causing stress deformation of the rear screw. When the deformation reaches a certain degree, the rear screw may bend or break, causing damage to the rear wheel steering gear.

[0051] Specifically, Figure 6 As shown, step S3-2 calculates the damage value of the rear wheel steering screw transmission mechanism model according to the calculated external load size, main force size and displacement of the rear wheel steering screw, and specifically includes the following steps: S3-2-1. The external load size, main force size and displacement of the rear wheel steering screw are input into the rear turn screw transmission mechanism model of the target vehicle to obtain the stress distribution of the rear wheel steering gear of the target vehicle; S3-2-2. Obtain the life curve of the rear wheel steering gear of the target vehicle, calculate the cumulative damage of the rear wheel steering gear based on the stress distribution, and use it as the damage value of the rear wheel steering gear of the target vehicle.

[0052] In the embodiment of the present invention, the life curve of the rear wheel steering gear of the target vehicle is the design parameter of the target vehicle, such as Figure 7The life curve is used to describe the service life of the target vehicle's rear wheel steering gear under different stress levels, which is related to factors such as the material and volume of the vehicle's rear screw. The inflection point of the life curve represents the breaking point or bending point of the target vehicle's rear screw. When the stress on the rear wheel steering gear reaches the stress level represented by the inflection point, the target vehicle's rear screw may bend or break.

[0053] After calculating the stress distribution of the rear wheel steering gear of the target vehicle through the rear screw model, the embodiment of the present invention obtains the life curve of the rear wheel steering gear, substitutes the stress output by the model into the life curve, and obtains the accumulated stress damage of the rear wheel steering gear during the steering operation.

[0054] Since the inflection point represented in the life curve is the damage point of the rear wheel steering gear of the target vehicle, when the rear wheel steering gear of the target vehicle reaches this inflection point, the rear wheel steering of the vehicle will fail and bring safety risks to the driver. Therefore, as a preferred embodiment, Figure 7 As shown, the damage monitoring method further includes the following steps: S4. Setting the damage threshold; S5. When the damage value of the vehicle's rear wheel steering gear exceeds the set damage critical value, the vehicle's rear wheel steering gear is controlled to stop working, and the vehicle is controlled to perform an alarm operation.

[0055] In a preferred embodiment, a damage critical value lower than the inflection point of the life curve is designed for the target vehicle, and this damage critical value is used as the durability threshold of the rear-wheel steering gear. When the rear-wheel steering gear of the target vehicle reaches the damage critical value, an alarm operation is initiated to avoid damage to the rear-wheel steering gear due to stress damage, which would affect the driver's safe driving.

[0056] Specifically, the alarm operation includes the following steps: S5-1. After the rear-wheel steering operation is completed, stop the target vehicle rear-wheel steering gear movement; S5-2. Send a rear wheel steering warning message to the driver.

[0057] As a preferred embodiment, when the rear-wheel steering gear of the target vehicle reaches the damage critical value, the rear-wheel steering system will stop moving after the driver completes the rear-wheel steering operation. At this time, the driver can no longer control the rear-wheel steering gear to perform rear-wheel steering operations. At the same time, the driver is prompted with warning information related to the service life of the rear-wheel steering gear, reminding the driver that the rear-wheel steering gear of the driver's vehicle has reached its service life and that it is necessary to contact the maintenance personnel of the target vehicle in time to maintain and repair the rear-wheel steering gear.

[0058] The embodiment of the present invention collects vehicle-related motion state signals to monitor the rear wheel angle, rear wheel angular velocity, vehicle speed, steering wheel angle, lateral acceleration, yaw angular velocity, rear wheel working state, etc. of the user's vehicle throughout its life cycle, and calculates the lateral force on the rear wheel through the vehicle's digital twin model. At the same time, based on the rear wheel angle and rear wheel angular velocity, the current rear wheel actuator durability damage can be calculated synchronously. The present invention can perform real-time damage prediction through big data monitoring and damage calculation strategies. When a certain damage threshold is accumulated and it is judged that there is a risk of damage, the vehicle is controlled to alarm and remind the driver to perform timely maintenance and repairs.

[0059] The second embodiment of the present invention provides a steering gear damage monitoring system for a rear-wheel steering vehicle. Figure 8 As shown, the steering gear damage monitoring system for a rear-wheel steering vehicle proposed in an embodiment of the present invention includes a data acquisition module, a vehicle digital twin module, and a damage calculation module. The data acquisition module is used to obtain the vehicle motion data of the target vehicle; the vehicle digital twin module is used to input the vehicle motion data into the vehicle dynamics model, and calculate the rear wheel steering parameters of the target vehicle in the vehicle dynamics model; the damage calculation module is used to calculate the damage value of the rear wheel steering gear of the target vehicle according to the rear wheel steering parameters.

[0060] The contents of the method in the first embodiment of the present invention are all applicable to this system embodiment. The functions specifically implemented by this system embodiment are the same as those of the above method embodiment, and the beneficial effects achieved are also the same as those achieved by the above method.

[0061] Fig. 9 : is a schematic diagram of the structure of the vehicle proposed in the third embodiment of the present invention. Exemplarily, the vehicle includes a processor and a memory coupled to the processor. Specifically, the vehicle can be a private car, such as a sedan, SUV, MPV or pickup truck. The vehicle can also be an operating vehicle, such as a van, a bus, a small truck or a large trailer. The vehicle can be a fuel vehicle or a new energy vehicle. When the vehicle is a new energy vehicle, it can be a hybrid vehicle or a pure electric vehicle. In this embodiment, the memory stores program instructions for implementing the steering gear damage monitoring method for a rear-wheel steering vehicle of any of the above embodiments. The processor is used to execute the program instructions stored in the memory to perform steering gear damage monitoring for a rear-wheel steering vehicle. Among them, the processor can also be called a CPU (Central Processing Unit). The processor may be an integrated circuit chip with signal processing capabilities. The processor can also be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0062] Fig.10 This is a schematic diagram of the structure of the storage medium of the fourth embodiment of the present invention. The storage medium of the fourth embodiment of the present invention stores program instructions that can implement the steering gear damage monitoring method of the above-mentioned rear-wheel steering vehicle, wherein the program instructions can be stored in the above-mentioned storage medium in the form of a software product, including a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) or a processor (processor) to execute all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, or terminal devices such as a computer, a server, a mobile phone, and a tablet.

[0063] This embodiment also provides a computer program product. When the computer program product is run on a computer, the computer is caused to execute the above-mentioned related steps to implement the steering gear damage monitoring method for a rear-wheel steering vehicle provided in the above-mentioned embodiment.

[0064] Those skilled in the art will appreciate that the modules in the devices in the embodiments of the present invention may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments of the present invention may be combined into one module or unit or component, and in addition they may be divided into a plurality of submodules or subunits or subcomponents. Except that at least some of such features and / or processes or units are mutually exclusive, all features disclosed in this specification (including the corresponding claims, abstracts and drawings) and all processes or units of any method or device disclosed in this manner may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the corresponding claims, abstracts and drawings) may be replaced by an alternative feature providing the same, equivalent or similar purpose.

[0065] Through the description of the above implementation methods, technical personnel in the relevant field can understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0066] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0067] In addition, each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other. In particular, for embodiments such as devices and equipment, since they are basically similar to method embodiments, the relevant parts can refer to the partial description of the method embodiments. The embodiments of the devices and equipment described above are merely schematic, wherein the modules, units, etc. described as separate components may or may not be physically separated, that is, they may be located in one place, or they may be distributed in multiple places, such as nodes of a system network. Specifically, some or all of the modules and units may be selected according to actual needs to achieve the purpose of the above-mentioned embodiment scheme. Those skilled in the art can understand and implement it without paying creative labor.

[0068] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0069] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0070] In addition, the terms "first", "second", etc. used in the embodiments of the present invention are only used for descriptive purposes and should not be understood as indicating or implying relative importance, or implicitly indicating the number of technical features indicated in the present embodiment. Therefore, the features defined by the terms "first", "second", etc. in the embodiments of the present invention can explicitly or implicitly indicate that the embodiment includes at least one of the features. In the description of the present invention, the word "multiple" means at least two or two or more, such as two, three, four, etc., unless otherwise clearly and specifically defined in the embodiments.

[0071] In the embodiments of the present invention, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "includes a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element. In addition, components, features, and elements with the same name in different embodiments of the present invention may have the same meaning or different meanings, and their specific meanings need to be determined by their explanation in the specific embodiment or further combined with the context in the specific embodiment.

[0072] Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and cannot be construed as limitations of the present invention, and those of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present invention. Those skilled in the art will readily come to think of other embodiments of the present invention after considering the specification and practicing the present invention. This application is intended to cover any variations, uses or adaptations of the present invention, which follow the general principles of the present invention and include common knowledge or customary technical means in the art that are not disclosed in the present invention. The specification and embodiments are intended to be exemplary only, and the true scope and spirit of the present invention are indicated by the following claims.

Claims

1. A method for monitoring steering gear damage of a rear-wheel steering vehicle, characterized in that: The following steps are involved: Obtaining vehicle motion data of a target vehicle; Inputting the vehicle motion data into a vehicle dynamics model, and calculating rear wheel steering parameters of the target vehicle in the vehicle dynamics model; The damage value of the rear wheel steering gear of the target vehicle is calculated according to the rear wheel steering parameters.

2. The method for monitoring steering gear damage of a rear-wheel steering vehicle according to claim 1, characterized in that: The vehicle motion data of the target vehicle includes at least the rear wheel steering angle, rear wheel steering angular velocity, lateral acceleration, yaw angular velocity, steering wheel angle and vehicle speed; Wherein, the rear wheel steering angle and rear wheel steering speed are obtained through the rear wheel steering device of the target vehicle; The lateral acceleration and yaw angular velocity are obtained by an inertial measurement unit of the target vehicle; The steering wheel angle is obtained through a steering system of the target vehicle; The vehicle speed is obtained through an anti-lock braking system of the target vehicle.

3. The method for monitoring steering gear damage of a rear-wheel steering vehicle according to claim 1, characterized in that: The vehicle dynamics model is a digital twin model of the target vehicle; the vehicle dynamics model can receive the vehicle motion data of the target vehicle in real time through the vehicle data interface, and update the vehicle dynamics model in real time according to the received vehicle motion data.

4. The method for monitoring steering gear damage of a rear-wheel steering vehicle according to claim 3, characterized in that: The step of inputting the vehicle motion data into a vehicle dynamics model and calculating the rear wheel steering parameters of the target vehicle in the vehicle dynamics model specifically comprises the following steps: Establishing a data transmission relationship between the target vehicle and the vehicle dynamics model through the vehicle data interface; When the target vehicle generates vehicle motion data, the vehicle motion data is transmitted to the vehicle dynamics model in real time through the vehicle data interface; The vehicle motion data is applied to a vehicle dynamics model to perform rear wheel steering calculation to obtain rear wheel steering parameters of the target vehicle.

5. The method for monitoring steering gear damage of a rear-wheel steering vehicle according to claim 1, characterized in that: The rear wheel steering parameters include rear wheel sideslip angle and rear wheel lateral force; Wherein, the rear wheel slip angle is calculated by the rear wheel speed angle output by the vehicle dynamics model; The rear wheel lateral force is calculated by combining the rear wheel speed angle output by the vehicle dynamics model with the cornering stiffness of the rear wheel.

6. The method for monitoring steering gear damage of a rear-wheel steering vehicle according to claim 1, characterized in that: The calculation of the damage value of the rear-rotating screw transmission mechanism model comprises the following steps: Calculate the external load, active force and displacement of the rear wheel steering screw; According to the calculated external load size, main force size and displacement of the rear wheel steering screw, the damage value of the rear wheel steering screw transmission mechanism model is calculated.

7. The method for monitoring steering gear damage of a rear-wheel steering vehicle according to claim 6, characterized in that: The external load size of the rear wheel steering screw is calculated based on the hard point position, wheel center position, ground contact point position, steering rod offset distance of the target vehicle's rear wheel steering gear assembly and the rear wheel lateral force.

8. The method for monitoring steering gear damage of a rear-wheel steering vehicle according to claim 6, characterized in that: The active force of the rear wheel steering screw is calculated by the following formula: The active force on the lead screw applied by the motor is calculated based on the motor assist torque of the rear wheel steering and the transmission ratio at this time.

9. The method for monitoring steering gear damage of a rear-wheel steering vehicle according to claim 6, characterized in that: The displacement of the rear wheel steering screw is calculated based on the motor assist torque of the rear wheel steering gear assembly in the vehicle dynamics model and the transmission ratio of the target vehicle.

10. The method for monitoring steering gear damage of a rear-wheel steering vehicle according to claim 6, characterized in that: The damage value of the rear wheel steering screw transmission mechanism model is calculated based on the calculated external load size, main force size and displacement of the rear wheel steering screw, and specifically includes the following steps: Inputting the external load magnitude, active force magnitude and displacement of the rear wheel steering screw into the rear wheel steering screw transmission mechanism model of the target vehicle to obtain the stress distribution of the rear wheel steering gear of the target vehicle; The life curve of the rear wheel steering gear of the target vehicle is obtained, and the accumulated damage of the rear wheel steering gear is calculated according to the stress distribution as the damage value of the rear wheel steering gear of the target vehicle.

11. The method for monitoring steering gear damage of a rear-wheel steering vehicle according to claim 1, characterized in that: The following steps are also included: Setting damage thresholds; When the damage value of the rear wheel steering gear of the vehicle exceeds the set damage critical value, the rear wheel steering gear of the vehicle is controlled to stop working, and the vehicle is controlled to perform an alarm operation.

12. The method for monitoring steering gear damage of a rear-wheel steering vehicle according to claim 11, characterized in that: The alarm operation specifically includes the following steps: After the rear wheel steering operation is completed, stopping the movement of the rear wheel steering gear of the target vehicle; Sends rear-wheel steering warning information to the driver.

13. A steering gear damage monitoring system for a rear-wheel steering vehicle, characterized in that: Includes data acquisition module, vehicle digital twin module and damage calculation module; The data acquisition module is used to obtain vehicle motion data of the target vehicle; The vehicle digital twin module is used to input the vehicle motion data into a vehicle dynamics model, and calculate the rear wheel steering parameters of the target vehicle in the vehicle dynamics model; The damage calculation module is used to calculate the damage value of the rear wheel steering gear of the target vehicle according to the rear wheel steering parameters.

14. A vehicle, characterized in that: The vehicle is equipped with an on-board computer, which includes a processor, a memory, and computer program instructions stored in the memory and executable on the processor. When the processor executes the computer program instructions, a steering gear damage monitoring method for a rear-wheel steering vehicle as described in any one of claims 1 to 12 is implemented.

15. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement a steering gear damage monitoring method for a rear-wheel steering vehicle as described in any one of claims 1 to 12 above.

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