1. A rail vehicle key component state testing method is characterized by comprising the following steps: the method comprises the following steps:

determining a rail vehicle structure, analyzing service conditions of all parts of the vehicle structure, and determining a measured point and corresponding measured parameters;

determining the type, the number and the layout position of the acquisition modules according to the measured points and the measured parameters to form a layout scheme;

acquiring the acquired data of each acquisition module in the layout scheme, and classifying the acquired data to obtain a test result;

and analyzing the test result, removing the acquisition modules which do not meet the requirements in the test result, optimizing the layout scheme, and performing state test on the rail vehicle key components by using the optimized layout scheme.

2. The method for testing the condition of the critical component of the railway vehicle as claimed in claim 1, wherein: determining a rail vehicle structure, analyzing service conditions of all parts of the vehicle structure, and selecting at least one of the following modes for determining a measured point:

(1) the method comprises the following steps of (1) taking a part of a railway vehicle bearing part with static stress exceeding a set threshold as a volatile part as a measured point through simulation calculation analysis;

(2) by analyzing the local structure of the connecting part, considering the part with stress concentration exceeding a preset threshold value as a volatile part as a measured point;

(3) determining a part with concentrated dynamic deformation on the structure according to the vibration characteristic of the bearing structure and the line disturbance condition, and considering a part which is possibly subjected to dynamic load exceeding a threshold value in the running process of a vehicle as a volatile part to serve as a measured point;

(4) a part of the same type of railway vehicle, which has fatigue cracks in the past fatigue test and operation, is obtained and considered as a volatile part to be used as a measured point.

3. The method for testing the condition of the critical component of the railway vehicle as claimed in claim 2, wherein: the specific process for determining the measured point and the corresponding measured parameter comprises the following steps: and determining the measured parameters of the measured point as load or/and dynamic stress related parameters according to the selected path of the measured point.

4. The method for testing the condition of the critical component of the railway vehicle as claimed in claim 1, wherein: determining the type, the number and the layout position of the acquisition modules according to the measured points and the measured parameters comprises the following requirements:

(1) arranging optical fiber strain sensors for parts with static stress exceeding a set threshold and parts with stress concentration exceeding a preset threshold;

(2) aiming at the dynamic deformation concentration part, the part exceeding the set threshold value dynamic load and the part with fatigue cracks, arranging an optical fiber strain sensor and an optical fiber acceleration sensor;

(3) each testing part is provided with an optical fiber temperature sensor;

(4) the sensors with the distance less than the set value are arranged in series.

5. The method for testing the condition of the critical component of the railway vehicle as claimed in claim 1, wherein: when a layout scheme is formed, a serial multi-parameter fiber grating sensor array is used for testing according to the requirements of temperature and strain measurement ranges, wherein the array comprises temperature sensors, strain sensors and acceleration sensors which are arranged at various tested points.

6. The method for testing the condition of the critical component of the railway vehicle as claimed in claim 1, wherein: when the layout scheme is formed, each sensor and each connecting optical cable are packaged and protected according to the requirements of the detection environment of the rail vehicle.

7. The method for testing the condition of the critical component of the railway vehicle as claimed in claim 6, wherein: the protective measures comprise: the optical cable is preliminarily fixed by a fixing piece, and the optical cable and the sensor are coated and protected for multiple times by protective coating;

and a protective sleeve is arranged outside the sensor.

8. The method for testing the condition of the critical component of the railway vehicle as claimed in claim 1, wherein: the process of classifying the collected data comprises the step of respectively processing a plurality of kinds of collected data of the temperature sensor, the strain sensor and the acceleration sensor.

9. The method for testing the condition of the critical component of the railway vehicle as claimed in claim 8, wherein: for the collected data of the temperature sensor, low-pass filtering is carried out by using a moving average filter, and a wavelength value is converted into a temperature value;

for the collected data of the strain sensor, converting the wavelength value into a strain value, calculating a main strain value of a tested part, converting the strain value into a stress value by combining the elastic modulus of the material, comparing thresholds and judging the load state of the current structure;

and for the acquired data of the acceleration sensor, converting the wavelength value into acceleration, performing high-pass filtering by using a Butterworth high-pass filter, comparing thresholds, judging whether the rail vehicle generates overload vibration during running, performing frequency spectrum analysis, and obtaining a vibration frequency distribution curve.

10. The method for testing the condition of the critical component of the railway vehicle as claimed in claim 1, wherein: analyzing the test result, wherein the specific measures for optimizing the layout scheme comprise at least one of the following measures:

analyzing the failure reason of the failure acquisition module, and removing the failure acquisition module or selecting the acquisition module with the matched type and protection mode to perform replacement installation at the corresponding position;

the acquisition module is used for removing the part where the strain or vibration signal is smaller than the set threshold value;

adding an acquisition module at an undetected part with structural damage or stress concentration;

and (3) replacing an acquisition module with matched acquisition range, accuracy or/and sensitivity to acquire the signal numerical range of the detected position.

11. A rail vehicle key component state testing device is characterized in that: the method comprises the following steps:

the measured point determining module is configured to determine a rail vehicle structure, analyze service conditions of all parts of the vehicle structure and determine a measured point and corresponding measured parameters;

the preliminary layout module is configured to determine the types, the number and the layout positions of the acquisition modules according to the measured points and the measured parameters to form a layout scheme;

the test result acquisition module is configured to acquire the acquired data of each acquisition module in the layout scheme and classify the acquired data to obtain a test result;

and the analysis optimization module is configured to analyze the test result, remove the acquisition module which does not meet the requirement in the test result and optimize the layout scheme.

12. A rail vehicle key component state test system is characterized in that: the device comprises an acquisition system and a testing device as claimed in claim 11, wherein the acquisition system comprises a plurality of acquisition modules, and the acquisition modules are arranged according to the optimized arrangement scheme determined by the testing device and are used for carrying out state testing on key components of the rail vehicle.

13. A rail vehicle key component state test system is characterized in that: the system comprises an acquisition system and an industrial personal computer, wherein the acquisition system comprises a plurality of acquisition modules, the acquisition modules are connected with the industrial personal computer, and the industrial personal computer is configured to execute the method of any one of claims 1-10 and acquire parameters of the acquisition modules at the relevant positions according to the optimized layout scheme.

14. The rail vehicle critical component condition testing system of claim 13, wherein: the system further comprises a positioning module for acquiring the running position information and/or the speed information of the rail vehicle.

15. The rail vehicle critical component condition testing system of claim 13, wherein: the acquisition module is at least one of a temperature sensor, a strain sensor and an acceleration sensor, and is connected with a multi-channel demodulator, and the multi-channel demodulator is connected with an industrial personal computer.

16. The rail vehicle critical component condition testing system of claim 13, wherein: the temperature sensor, the strain sensor and the acceleration sensor are fiber grating sensors and respectively comprise a fiber grating and a flexible protective shell, the flexible protective shell is used for protecting the fiber grating positioned on the inner side of the flexible protective shell, and the flexible protective shell is provided with a coating.

Background

The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.

In recent years, fiber grating sensing has rapidly developed as a new technology. The fiber grating sensor has the characteristics of wide dynamic monitoring range, high sensitivity and the like due to the photosensitivity, and in addition, the fiber grating sensor has long optical signal transmission distance and strong electromagnetic interference resistance, thereby overcoming the defects of the traditional sensor. With the continuous improvement of the manufacturing process of the fiber bragg grating, the fiber bragg grating has the characteristics of small volume, light weight, flexible structural design, easy operation of the packaging process, realization of detection of multiple parameters such as temperature, strain, displacement and the like, and realization of distributed measurement, so that the fiber bragg grating sensing technology becomes an ideal means for monitoring the key structural state of equipment in real time.

However, as the inventor knows, the conventional fiber grating detection system cannot be applied to the complex situation due to the complex structure and the various types of key components of the rail vehicle, and cannot meet the load dynamic stress strain detection requirement of the rail vehicle.

Disclosure of Invention

The state testing system is constructed aiming at the state monitoring requirement of the rail vehicle key structural component, the information such as real-time dynamic stress, temperature, load and the like of the rail vehicle key bearing structural component in the rail vehicle running state is monitored, the running state of the key structure can be monitored, abnormal information can be found in time, and the safe running of the rail vehicle is guaranteed.

According to some embodiments, the following technical scheme is adopted in the disclosure:

the first purpose of the present disclosure is to provide a rail vehicle key component state testing method, which includes the following steps:

determining a rail vehicle structure, analyzing service conditions of all parts of the vehicle structure, and determining a measured point and corresponding measured parameters;

determining the type, the number and the layout position of the acquisition modules according to the measured points and the measured parameters to form a layout scheme;

acquiring the acquired data of each acquisition module in the layout scheme, and classifying the acquired data to obtain a test result;

and analyzing the test result, removing the acquisition modules which do not meet the requirements in the test result, optimizing the layout scheme, and performing state test on the rail vehicle key components by using the optimized layout scheme.

As an alternative embodiment, the rail vehicle structure is determined, the service conditions of all parts of the vehicle structure are analyzed, and the measured point is determined in at least one of the following modes:

(1) the method comprises the following steps of (1) taking a part of a railway vehicle bearing part with static stress exceeding a set threshold as a volatile part as a measured point through simulation calculation analysis;

(2) by analyzing the local structure of the connecting part, considering the part with stress concentration exceeding a preset threshold value as a volatile part as a measured point;

(3) determining a part with concentrated dynamic deformation on the structure according to the vibration characteristic of the bearing structure and the line disturbance condition, and considering a part which is possibly subjected to dynamic load exceeding a threshold value in the running process of a vehicle as a volatile part to serve as a measured point;

(4) a part of the same type of railway vehicle, which has fatigue cracks in the past fatigue test and operation, is obtained and considered as a volatile part to be used as a measured point.

As a further limitation, the specific process of determining the measured point and the corresponding measured parameter comprises the following steps: and determining the measured parameters of the measured point as load or/and dynamic stress related parameters according to the selected path of the measured point.

As an alternative implementation mode, according to the measured points and the measured parameters, the determination of the type, the number and the layout position of the acquisition modules comprises the following requirements:

(1) arranging optical fiber strain sensors for parts with static stress exceeding a set threshold and parts with stress concentration exceeding a preset threshold;

(2) aiming at the dynamic deformation concentration part, the part exceeding the set threshold value dynamic load and the part with fatigue cracks, arranging an optical fiber strain sensor and an optical fiber acceleration sensor;

(3) each testing part is provided with an optical fiber temperature sensor;

(4) the sensors with the distance less than the set value are arranged in series.

As an alternative embodiment, when the layout scheme is formed, the test is carried out by utilizing a series-type multi-parameter fiber bragg grating sensor array aiming at the temperature and strain measurement range requirement, and the array comprises a temperature sensor, a strain sensor and an acceleration sensor which are arranged at each tested point.

As an alternative embodiment, when the layout scheme is formed, the sensors and the connecting optical cables are packaged and protected according to the detection environment requirements of the rail vehicle.

By way of further limitation, the protective measures include: the optical cable is preliminarily fixed by a fixing piece, and the optical cable and the sensor are coated and protected for multiple times by protective coating;

and a protective sleeve is arranged outside the sensor.

As an alternative embodiment, the process of classifying the collected data includes processing several kinds of collected data of the temperature sensor, the strain sensor and the acceleration sensor separately.

As a further limitation, for the collected data of the temperature sensor, low-pass filtering is carried out by using a moving average filter, and the wavelength value is converted into a temperature value;

for the collected data of the strain sensor, converting the wavelength value into a strain value, calculating a main strain value of a tested part, converting the strain value into a stress value by combining the elastic modulus of the material, comparing thresholds and judging the load state of the current structure;

and for the acquired data of the acceleration sensor, converting the wavelength value into acceleration, performing high-pass filtering by using a Butterworth high-pass filter, comparing thresholds, judging whether the rail vehicle generates overload vibration during running, performing frequency spectrum analysis, and obtaining a vibration frequency distribution curve.

As an alternative embodiment, the test result is analyzed, and the specific measure for optimizing the layout scheme includes at least one of the following measures:

analyzing the failure reason of the failure acquisition module, and removing the failure acquisition module or selecting the acquisition module with the matched type and protection mode to perform replacement installation at the corresponding position;

the acquisition module is used for removing the part where the strain or vibration signal is smaller than the set threshold value;

adding an acquisition module at an undetected part with structural damage or stress concentration;

and (3) replacing an acquisition module with matched acquisition range, accuracy or/and sensitivity to acquire the signal numerical range of the detected position.

A second object of the present disclosure is to provide a rail vehicle key component status testing device, including:

the measured point determining module is configured to determine a rail vehicle structure, analyze service conditions of all parts of the vehicle structure and determine a measured point and corresponding measured parameters;

the preliminary layout module is configured to determine the types, the number and the layout positions of the acquisition modules according to the measured points and the measured parameters to form a layout scheme;

the test result acquisition module is configured to acquire the acquired data of each acquisition module in the layout scheme and classify the acquired data to obtain a test result;

and the analysis optimization module is configured to analyze the test result, remove the acquisition module which does not meet the requirement in the test result and optimize the layout scheme.

The third purpose of the present disclosure is to provide a rail vehicle key component state testing system, which includes an acquisition system and the above-mentioned testing device, where the acquisition system includes a plurality of acquisition modules, and the acquisition modules are arranged according to the optimized arrangement scheme determined by the testing device, and perform rail vehicle key component state testing.

The fourth purpose of the present disclosure is to provide a rail vehicle key component state testing system, which includes an acquisition system and an industrial personal computer, wherein the acquisition system includes a plurality of acquisition modules, the acquisition modules are connected with the industrial personal computer, and the industrial personal computer is configured to execute the above method, and acquires parameters of the acquisition modules at relevant positions according to an optimized layout scheme.

The system further comprises a positioning module for acquiring the running position information and/or the speed information of the rail vehicle.

The acquisition module is at least one of a temperature sensor, a strain sensor and an acceleration sensor, and is connected with a multi-channel demodulator, and the multi-channel demodulator is connected with an industrial personal computer.

The temperature sensor, the strain sensor and the acceleration sensor are fiber grating sensors.

The collection module comprises a fiber grating and a flexible protective shell, the flexible protective shell is used for protecting the fiber grating located on the inner side of the flexible protective shell, and the flexible protective shell is provided with a coating.

Compared with the prior art, the beneficial effect of this disclosure is:

the method is based on the research on the real-time online detection technology of the structural state of the fiber bragg grating sensing technology, and can realize the detection of service load and dynamic stress of key components of rail transit equipment.

According to the method, the real-time online monitoring system for the key structural state of the rail vehicle, which is suitable for engineering application, can be constructed by utilizing an optimization method, key tests can be performed on necessary test areas in a targeted manner, an optimal layout scheme is obtained, and the problems that the key parts of the high-speed rail vehicle are complex in structure and difficult to deploy, and the adverse environmental influences such as electromagnetic interference are caused are solved.

According to the method, the parts with large static stress are considered as volatile effective parts through simulation calculation and analysis of the bearing parts of the rail vehicle, the parts with large static stress can become weak parts for resisting fatigue damage, an optical fiber strain sensor and an optical fiber acceleration sensor are arranged aiming at dynamic deformation concentrated parts, large dynamic load parts and parts with fatigue cracks, an optical fiber temperature sensor is arranged at each testing part, corresponding information of the bearing parts of the rail vehicle can be effectively acquired, and the accuracy of state analysis is guaranteed.

In order to make the aforementioned objects, features and advantages of the present disclosure more comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure and are not to limit the disclosure.

FIG. 1 is an architecture of an online monitoring system for dynamic stress of a critical component load of a rail vehicle according to the embodiment;

fig. 2 is a schematic view of a process of testing the load and dynamic stress of the key components of the rail vehicle according to the embodiment.

The specific implementation mode is as follows:

the present disclosure is further described with reference to the following drawings and examples.

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

In the present disclosure, terms such as "upper", "lower", "left", "right", "front", "rear", "vertical", "horizontal", "side", "bottom", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only relational terms determined for convenience in describing structural relationships of the parts or elements of the present disclosure, and do not refer to any parts or elements of the present disclosure, and are not to be construed as limiting the present disclosure.

In the present disclosure, terms such as "fixedly connected", "connected", and the like are to be understood in a broad sense, and mean either a fixed connection or an integrally connected or detachable connection; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present disclosure can be determined on a case-by-case basis by persons skilled in the relevant art or technicians, and are not to be construed as limitations of the present disclosure.

As shown in fig. 1, the embodiment provides a load and dynamic stress test system suitable for rail vehicles, around the load dynamic stress strain detection demand of high-speed rail vehicles, based on fiber grating sensor network technology, build a high-speed rail vehicle key component load and dynamic stress on-line monitoring system, the monitoring system comprises a demodulator, a multi-channel fiber sensor, a control computer and a positioning module, wherein the multi-channel fiber sensor is installed on the surface of a measured object, the demodulator, the computer and the positioning module are located inside a carriage, and the sensor and the demodulator are connected by an armored optical cable.

Certainly, aiming at the detection environment of the rail vehicle, the packaging and optical cable arrangement mode of the sensor has the functions of vibration prevention, dust prevention and water prevention.

In this embodiment, a dedicated fiber grating sensor and an integrated network are designed around the requirement of the detection index of the key component and the arrangement scheme of the sensor.

Researching a cross sensitivity mechanism of fiber bragg grating measurement, and designing a fiber bragg grating dynamic strain sensor, wherein the sensor consists of a fiber bragg grating and a rubber protective shell, the fiber bragg grating is a sensitive element, and the rubber protective shell plays a role in protection;

aiming at the requirements of measurement ranges such as temperature, strain and the like, a series multi-parameter fiber grating sensor array meeting the requirements of high and low temperature and large strain ranges is adopted, and the array comprises a temperature sensor, a strain sensor and an acceleration sensor which are respectively used for detecting temperature, strain and acceleration information;

aiming at the detection environment of the rail vehicle, the sensor packaging and optical cable laying mode with vibration-proof, dustproof and waterproof functions is designed, and the protection mode is as follows: firstly, preliminarily fixing the optical cable by using a wire bundling plate and a bundling belt; and then, coating and protecting the optical cable and the sensor by using the RTV single-component room temperature vulcanized silicone rubber, wherein three times of coating is needed, and the thickness of the coating is 1-3 mm each time.

The characteristics of strong vibration, large temperature change and the like of the running environment of the railway vehicle are considered, and the fiber grating demodulator is in a fully static state, high-speed, multi-channel and high-precision state, so that the strain and load information can be acquired at high speed and high precision.

Meanwhile, in some embodiments, the railway vehicle monitoring system further comprises a positioning module, and the GPS/Beidou/GLONASS positioning technology is utilized to realize real-time acquisition of the running position information and the speed information of the railway vehicle, so that multidimensional data support is provided for analysis of structural stress and load state of the railway vehicle.

Of course, in other embodiments, the positioning module may adopt corresponding modules of other positioning technologies as long as the operation position information and the speed information of the rail vehicle can be obtained.

The software system collects multi-parameter information such as strain, temperature, load, positioning and speed at a high speed, preprocesses and displays visual curves on the data, and simultaneously stores the current multi-parameter data in real time, thereby providing a data base for subsequent database construction and data off-line processing.

According to the requirements of a monitoring system, the control computer is provided with a visual human-computer interaction platform, so that real-time reading, processing, displaying and storing of data can be realized, the parameters of the demodulator are controlled in real time by utilizing the communication between the control computer and the demodulator, and the central wavelength data of the sensor is obtained; the control computer is communicated with the GPS/Beidou positioning module to acquire the position and running speed information of the rail vehicle in real time; displaying dynamic stress data of key components of the rail vehicle, position and speed information of the rail vehicle on a display of a human-computer interaction platform in real time, and performing curve display; the control computer has a real-time data storage function, and the data is stored in a txt or x l s format.

In some embodiments, the sensor may also be another type of sensor, and in this embodiment, the advantage of the fiber grating sensor is that the fiber grating sensor has the characteristics of wide dynamic monitoring range, high sensitivity, and the like due to its photosensitivity, and in addition, the optical signal transmission distance is long, and the anti-electromagnetic interference is strong, thereby overcoming the defects of the conventional sensor. With the continuous improvement of the manufacturing process of the fiber bragg grating, the fiber bragg grating has the characteristics of small volume, light weight, flexible structural design, easy operation of the packaging process, realization of detection of multiple parameters such as temperature, strain and displacement and realization of distributed measurement.

In the embodiment, the test system is utilized to monitor the information of the key bearing structure part of the rail vehicle such as real-time dynamic stress, temperature, load and the like in the running state of the rail vehicle, monitor the running state of the key structure, discover abnormal information in time and ensure the safe running of the rail vehicle.

As shown in fig. 2, the setting of the specific sensor positions, and the testing process, includes the following steps:

(1) judging the easy failure parts of the railway vehicle:

determining failed parts through simulation and actual railway vehicle operation experience, wherein the failed parts comprise the following 4 types of volatile parts:

firstly, through simulation calculation and analysis of a bearing part of the railway vehicle, parts with large static stress are considered as volatile effective parts, and the parts with large static stress can become weak parts for resisting fatigue failure;

secondly, by analyzing the local structure of the connecting part, the part with larger stress concentration is considered as a volatile part;

determining a part with concentrated dynamic deformation on the structure according to the vibration characteristic of the bearing structure and the line disturbance condition, and considering the part which can bear larger dynamic load in the running of the vehicle as a volatile effect part;

and fourthly, investigating and analyzing the parts of the structure, which have fatigue cracks in fatigue tests and actual operation, and considering the parts as volatile parts.

(2) Sensor arrangement:

based on the structural characteristics and structural importance degree of the easily-damaged part, the sensor arrangement mode is reasonably designed by combining the technical characteristics of fiber bragg grating sensing.

Arranging optical fiber strain sensors for parts with larger static stress and parts with larger stress concentration;

secondly, arranging an optical fiber strain sensor and an optical fiber acceleration sensor aiming at the dynamic deformation concentrated part, the part with larger dynamic load and the part with fatigue crack;

and thirdly, arranging optical fiber temperature sensors at each testing part.

And fourthly, the sensors arranged in the similar positions can be arranged in a series connection mode, so that the optical cable routing is reduced.

(3) Signal analysis:

according to the structure detection index requirement, the sensor arrangement mode and the characteristics of the sensors, the detection signal is preprocessed and analyzed, and the method comprises the following steps:

firstly, processing a temperature sensor signal, wherein the processing method comprises the following steps: firstly, low-pass filtering is carried out by using a moving average filter, and the data length can be set to be 1 s; then, converting the wavelength value into a temperature value according to a sensor calculation formula;

processing the signal of the strain sensor, wherein the processing method comprises the following steps: firstly, converting a wavelength value into a strain value according to a strain sensor calculation formula; then, calculating a main strain value of the test part; thirdly, converting the strain value into a stress value by combining the elastic modulus of the material; and finally, comparing the threshold values and judging the load state of the current structure.

Processing signals of the acceleration sensor, wherein the processing method comprises the following steps: firstly, converting a wavelength value into acceleration according to an acceleration sensor calculation formula; secondly, performing high-pass filtering by using a Butterworth high-pass filter, wherein the setting range of cut-off frequency is 1-100 Hz; thirdly, comparing threshold values, and judging whether the rail vehicle generates overload vibration during running; and finally, carrying out frequency spectrum analysis to obtain a vibration frequency distribution curve.

(4) Correcting or adjusting the sensor system according to the result of the analysis of the measured data

The developed load dynamic stress strain detection system is utilized to carry out a line running test aiming at the online operation high-speed rail vehicle, test and analyze the load and dynamic stress data of the key bearing part of the vehicle, and correct or adjust the system according to the analysis result, and the method comprises the following steps:

sensor failure: and analyzing the failure reasons of the sensors, and selecting proper sensor types and protection modes for replacement and installation according to the failure reasons.

Secondly, optimizing the sensor arrangement: for the part with smaller strain and vibration signal in the long-term test, the test part can be removed in the subsequent system design; in the long-term test, if structural damage or stress concentration occurs at an undetected site, the site should be increased as a detected site.

And thirdly, optimizing the sensor indexes. According to the numerical range of the sensor to be detected, the sensor index is further optimized, and a sensor with proper measurement range, accuracy and sensitivity is selected in subsequent system design aiming at a specific detection part.

And fourthly, optimizing system indexes. And optimizing the data acquisition opportunity and the acquisition frequency according to the frequency range and the numerical range of the detected information.

In summary, in the embodiment, with the goal of research on load and dynamic stress response of key bearing parts of the rail vehicle, the advanced structural health monitoring and safety assessment concepts and technologies are introduced into the field of high-speed rail transit equipment, a fiber bragg grating sensing technology is adopted to research and develop vehicle-mounted sensors, demodulation equipment, data processing and communication software and the like, the problems that the key parts of the high-speed rail vehicle are complex in structure and difficult to deploy, and the adverse environmental influences such as electromagnetic interference are caused are solved, and a method, a system and a technical system which are suitable for online monitoring of the key structural state of the high-speed rail vehicle are constructed.

The above description is only a preferred embodiment of the present disclosure and is not intended to limit the present disclosure, and various modifications and changes may be made to the present disclosure by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present disclosure should be included in the protection scope of the present disclosure.

Although the present disclosure has been described with reference to specific embodiments, it should be understood that the scope of the present disclosure is not limited thereto, and those skilled in the art will appreciate that various modifications and changes can be made without departing from the spirit and scope of the present disclosure.