CN114547887A

CN114547887A - Method for compiling multichannel load spectrum

Info

Publication number: CN114547887A
Application number: CN202210160540.0A
Authority: CN
Inventors: 于佳伟; 马健君; 任俊学; 刘子豪; 苏泊权
Original assignee: Shanghai Motor Vehicle Inspection Certification and Tech Innovation Center Co Ltd
Current assignee: Shanghai Motor Vehicle Inspection Certification and Tech Innovation Center Co Ltd
Priority date: 2022-02-22
Filing date: 2022-02-22
Publication date: 2022-05-27

Abstract

The invention relates to a compiling method and a compiling device for a multichannel load spectrum and a computer readable storage medium. The multichannel load spectrum compiling method comprises the steps of S1, inputting multichannel load spectrums, setting a pseudo-damage retention proportion target and a duration screening threshold Tt, and setting a small load threshold Ta of the load spectrums of each channel; s2, traversing the load spectrum, finding all load time periods according to the duration screening threshold Tt and the small load threshold Ta, and calculating the intersection of the load time periods of multiple channels; s3, judging whether the pseudo-damage retention ratio target is met, if one channel is met, turning to the step S4; if all the channels do not meet the preset standard, modifying the small load threshold Ta, and turning to the step S2; and S4, outputting the multichannel acceleration spectrum. The invention provides a compilation method, compilation equipment and a computer readable storage medium of a multi-channel load spectrum, which can realize high-efficiency compilation of the load spectrum, have small analysis difficulty and are convenient for engineering application.

Description

Method for compiling multichannel load spectrum

Technical Field

The invention relates to the technical field of vehicle road simulation tests, in particular to a method for compiling a multichannel load spectrum.

Background

At present, two mainstream technologies exist in the technical field of vehicle road simulation tests, including a mature time domain damage editing method and a novel road simulation test random load spectrum editing method based on short-time Fourier transform and wavelet transform.

One, time domain damage editing method

The damage-time distribution characteristics of the local detail strain/force load spectrum of the structural part are calculated, load spectrum time-domain history information with small damage is identified and acquired, and load spectrum duration is shortened by deleting the load spectrum time-domain history with small damage, so that test load spectrum compiling is realized.

When a time domain damage editing method is used for compiling a test load spectrum, researchers must have a strain/force load spectrum of local details of a tested structural part. In more practical engineering applications, a tester only has an external excitation load spectrum (such as force, displacement, acceleration and the like) of a tested structural member, so that the engineering applicability of the method is insufficient. In addition, the strain/force load spectrum of the local details of the structural member can be obtained through virtual simulation by establishing a finite element model, but the method is limited by the accuracy of the finite element model. Or the strain gauge is attached to the fatigue dangerous part of the tested structural member and the measurement is carried out on the actual road, the method is restricted by data acquisition resources, manpower and material resources, and the difficulty in measuring the strain/force spectrum of the most dangerous part of the structural member is higher.

Random load spectrum editing method

(1) The short-time Fourier transform analysis method is characterized in that the time-energy (accumulated power spectral density) distribution characteristics of the load spectrum are analyzed, and the time segment of the load spectrum with energy lower than a set threshold value is positioned and deleted, so that the reduction of the load spectrum time length is realized.

The short-time Fourier transform analysis method is used for analyzing the time-frequency characteristics of the load spectrum, and relates to more parameters, such as the number of discrete Fourier transform points, the overlapping proportion between time windows, the type of a window function and the like, wherein the parameters have certain influence on the analysis and calculation result of the load spectrum, and the analysis difficulty is higher.

(2) The wavelet transform analysis method decomposes a load spectrum into multiple wavelet coefficients, and identifies and deletes a time history corresponding to a low-amplitude load by researching the characteristics (such as accumulated power spectral density, amplitude variation trend and the like) of the wavelet coefficients under multi-resolution, thereby realizing the reduction of the time duration of the load spectrum.

The algorithm for compiling the test load spectrum based on the wavelet transform analysis method is complex, the wavelet function type, the wavelet decomposition layer number and the definition of the small load characteristics all have certain influence on the load spectrum compiling result, and the analysis difficulty is high.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a method for compiling a multi-channel load spectrum, which realizes the efficient compilation of the load spectrum, has small analysis difficulty and is convenient for engineering application.

Specifically, the invention provides a method for compiling a multichannel load spectrum, which comprises the following steps:

s1, inputting the load spectrums of multiple channels, setting a pseudo-damage retention ratio target and a duration screening threshold Tt, and setting a small load threshold Ta of the load spectrums of each channel;

s2, traversing the load spectrum, finding all load time periods according to the duration screening threshold Tt and the small load threshold Ta, calculating the intersection of the load time periods of multiple channels, deleting the time periods corresponding to the intersection on the load spectrum, and connecting and reconstructing the time periods of the remaining load spectrum to generate an acceleration spectrum of multiple channels;

s3, calculating and comparing the rain flow circulation of the load spectrum and the acceleration spectrum of each channel, judging whether the pseudo-damage retention proportion target is met, and if one channel is met, turning to the step S4; if all the channels do not accord with the preset threshold value Ta, modifying the small load threshold value Ta and switching to a step S2;

and S4, outputting the acceleration spectrum of multiple channels.

According to one embodiment of the present invention, finding all load time periods in step S2 includes:

s21, searching load time periods which accord with the small load threshold Ta on the load spectrum, and calculating the time length delta t of each load time period;

and S22, if the time length delta t of the load time period is greater than the duration screening threshold Tt, the load time period is a target to be searched.

According to an embodiment of the present invention, in step S1, an upper threshold limit T of the small load threshold Ta for each channel is set_a,up＝M+(A_max-M)·na_thSetting a lower threshold T of the small load threshold Ta_a,down＝M-(M-A_min)·na_th；

Wherein M is the mean value of the load channels of the load spectrum, A_maxIs the maximum of the load path of the load spectrum, A_minIs the minimum value of the load channel of the load spectrum, parameter alpha_thThe threshold value increasing coefficient is set to be a constant, and the parameter n is a natural number.

According to an embodiment of the present invention, in step S1, a parameter α is set_thThe initial value of parameter n is 0.01, 1.

According to an embodiment of the present invention, in step S3, modifying the small loading threshold Ta refers to modifying the parameter α_thAnd/or a parameter n to recalculate the small load threshold Ta.

According to one embodiment of the present invention, the operation of concatenating and reconstructing the time segments of the load spectrum of the remaining multiple channels to generate an acceleration spectrum of the multiple channels in step S2 includes concatenating the time segments of the load spectrum of the remaining multiple channels using a signal smoothing technique.

According to an embodiment of the invention, in step S2, transition signals of suitable length are added at both ends of the reconstructed signal of the load spectrum.

The invention also provides a multichannel load spectrum compiling device which comprises a memory, a processor and a computer program which is stored on the memory and can run on the processor, wherein the processor realizes the steps of any one of the compiling methods when executing the computer program.

The invention also provides a computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the steps of the programming method of any one of the preceding claims.

The method for compiling the multi-channel load spectrum provided by the invention is combined with the pseudo-damage retention criterion, can realize high-efficiency compilation of the load spectrum, is low in analysis difficulty and is convenient for engineering application.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

Drawings

The accompanying drawings, which are included to provide a further explanation of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. In the drawings:

fig. 1 shows a flow chart of a compilation method of a multichannel load spectrum according to an embodiment of the invention.

Fig. 2 shows a load spectrum which has not been processed by the programming method of the invention.

FIG. 3 is an acceleration spectrum of FIG. 2 processed by the programming method of the present invention.

FIG. 4A shows a load spectrum of vertical displacement of the left front wheel of the entire vehicle.

FIG. 4B shows a load spectrum of vertical displacement of the right front wheel of the entire vehicle.

FIG. 5 shows the parameter α of the pseudo-damage retention ratio of each channel with respect to the small loading threshold Ta_thA trend graph of growth.

Fig. 6A is an identification diagram of the small loading threshold Ta of fig. 4A under the condition that the pseudo damage retention ratio target is 90%.

Fig. 6B is an identification diagram of the small loading threshold Ta of fig. 4B under the condition that the pseudo damage retention ratio target is 90%.

Fig. 7A is a load spectrum for fig. 4A labeled load time period intersection for small loads.

Fig. 7B is a load spectrum for fig. 4B labeled load time period intersections for small loads.

Fig. 8 is the acceleration spectrum of fig. 4B with a pseudo lesion retention ratio target of 90%.

FIG. 9A shows a cumulative cycle count comparison plot of the acceleration and load spectra of the left front wheel of the entire vehicle.

FIG. 9B shows a cumulative cycle count comparison of the acceleration and load spectra of the right front wheel of the entire vehicle.

FIG. 10A shows a PSD analysis comparison graph of acceleration and load spectra of a left front wheel of a full vehicle.

FIG. 10B shows a PSD analysis comparison graph of the acceleration spectrum and the load spectrum of the right front wheel of the entire vehicle.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the application, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

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 application. 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.

The relative arrangement of the components and steps, the numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present application unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

In the description of the present application, it is to be understood that the orientation or positional relationship indicated by the directional terms such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc., are generally based on the orientation or positional relationship shown in the drawings, and are used for convenience of description and simplicity of description only, and in the case of not making a reverse description, these directional terms do not indicate and imply that the device or element being referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore, should not be considered as limiting the scope of the present application; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of protection of the present application is not to be construed as being limited. Further, although the terms used in the present application are selected from publicly known and used terms, some of the terms mentioned in the specification of the present application may be selected by the applicant at his or her discretion, the detailed meanings of which are described in relevant parts of the description herein. Further, it is required that the present application is understood not only by the actual terms used but also by the meaning of each term lying within.

Fig. 1 shows a flow chart of a compilation method of a multichannel load spectrum according to an embodiment of the invention. As shown in the figure, the compilation method of the multichannel load spectrum provided by the invention comprises the following steps:

and S1, inputting the load spectrum of each channel in the multiple channels, and setting a pseudo damage retention ratio target and a duration screening threshold Tt. A small loading threshold Ta of the loading spectrum of each channel is set.

And S2, traversing the load spectrum, and searching all load time periods meeting the conditions according to the time length screening threshold Tt and the small load threshold Ta. And calculating the intersection of the load time periods of the multiple channels, and deleting the time period corresponding to the intersection on the load spectrum of each channel. The time segments of the remaining load spectrum are concatenated and reconstructed to generate the acceleration spectrum on each channel.

And S3, calculating and comparing the rain flow circulation of the load spectrum and the acceleration spectrum of each channel, and judging whether the rain flow circulation meets the pseudo-damage retention ratio target. If any channel meets the pseudo-damage retention ratio target, the step S4 is executed; if all the channels do not meet the preset standard, modifying the small load threshold Ta, and turning to the step S2;

and S4, outputting a multichannel acceleration spectrum, wherein the acceleration spectrum is the result obtained by the programming method.

Preferably, in step S2, finding all load time periods includes:

s21, searching load time periods which accord with a small load threshold Ta on the load spectrum, and calculating the time length delta t of each load time period;

Preferably, in step S1, an upper threshold limit T of the small load threshold Ta for each lane is set_a,up＝M+(A_max-M)·na_thSetting a lower threshold T of the small load threshold Ta_a,down＝M-(M-A_min)·na_th. Because the small load identification threshold Ta relates to the definition of invalid loads, a unified criterion is not formed in the aspect of deleting the small loads in a load spectrum at present, and the small load identification threshold Ta is difficult to accurately obtain. Therefore, the small load recognition threshold Ta is determined using the pseudo damage retention ratio target in the present invention. In other words, if the pseudo damage retention ratio target is not reached, the value of the small load recognition threshold Ta needs to be adjusted repeatedly.

Above-mentioned thresholdIn the value expression, M is the mean value of the load channel of the load spectrum, A_maxIs the maximum value of the load path of the load spectrum, A_minIs the minimum value of the load path of the load spectrum, parameter alpha_thThe threshold value increasing coefficient is set to be a constant, and the parameter n is a natural number. More preferably, a parameter α is set_thThe initial value of the parameter n is 1, and n is n +1, n α in the threshold setting of the small load threshold Ta in the iterative process_thEach increment was 0.01. By way of example, and not limitation, the parameter α_thCan also be set to 0.001, 0.1 or other values meeting the set requirements; the initial value of the parameter n may be other natural numbers.

Preferably, in step S3, modifying the small load threshold Ta refers to modifying the parameter α_thAnd/or the parameter n to recalculate the threshold range of the small load threshold Ta. Conventionally, only the parameter n is adjusted, the value of the parameter n is updated by setting the step size to 1 through a plurality of iterations, the load time period is calculated in step S2, and in step S3 until either channel meets the pseudo-damage retention ratio target.

Preferably, the operation of concatenating and reconstructing the time segments of the remaining multi-channel load spectrum to generate the multi-channel acceleration spectrum in step S2 includes concatenating the time segments of the remaining load spectrum using a signal smoothing technique.

Preferably, in step S2, transition signals of appropriate length are added at both ends of the signal of the reconstructed load spectrum. In order to avoid the impact of the acceleration spectrum obtained by the compiling method of the invention on the equipment actuating cylinder in the subsequent bench test, transition signals with proper lengths are added at two ends of the reconstructed load spectrum signal to form the acceleration spectrum.

Fig. 2 shows a load spectrum which has not been processed by the programming method of the invention. FIG. 3 is an acceleration spectrum of FIG. 2 processed by the programming method of the present invention. Referring to fig. 2, a single channel load spectrum is shown with time on the horizontal axis and load on the vertical axis. A jagged line 201 represents a random load course varying with time, and upper and lower parallel dashed

lines

202 and 203 represent an upper threshold limit of the small load recognition threshold Ta and a lower threshold limit of the small load recognition threshold Ta, respectively. Capital letters A and N represent head and tail data (time) points of the load spectrum, and capital letters B, C, D, E, F, G, H, I, J, K, L and M represent time points corresponding to the intersection of the sawtooth line and the two threshold dotted lines in the load spectrum respectively. It is easily understood that, for example, from the time points a to B and the time points C to D, the loading time periods AB, CD conforming to the small load recognition threshold Ta are formed, i.e., the loading time periods AB, CD fall between the upper threshold limit and the lower threshold limit of the small load recognition threshold Ta. Similarly, the load time periods EF, GH, IJ, KL, and MN are all load time periods that meet the small load identification threshold Ta. Based on the time length screening threshold Tt set in step S1, the time lengths Δ t of the respective loading periods AB, CD, EF, GH, IJ, KL, and MN (the time lengths from the start point to the end point of the respective loading periods) are calculated, respectively, and it is determined whether or not the time length Δ t of the small load segment is greater than the time length screening threshold Tt. If the time length delta t of the found load time period is greater than the duration screening threshold Tt, the load time period is a searched target and is marked as O; if the time length Δ t of the found load time period is not greater than the duration screening threshold Tt, the load time period is a non-target to be found, i.e., it is determined that the payload segment should be reserved, and the segment is marked as R. And setting the time lengths delta t of the load time periods AB, CD, IJ and MN to be larger than the duration screening threshold Tt, and judging the load time periods to be in accordance with the target searching. The time lengths of the load time periods EF, GH and KL are not greater than the duration screening threshold Tt and are reserved.

Next, the intersection of the load periods of the multiple passes is calculated. For example, if there is another channel of load spectrum processed by the above steps, and the time length Δ t of the load time periods C 'D' and I 'J' is greater than the duration screening threshold Tt, the two load time periods are the target of searching. The time span of the load time period CD is assumed to be 15-18 s, the time span of the load time period IJ is assumed to be 24-26 s, the time span of the load time period C 'D' is assumed to be 16-19 s, and the time span of the load time period I 'J' is assumed to be 25-27 s. The intersection of the load time periods of the two channels is a load time period C 'D and a load time period I' J, the time span of the load time period C 'D is 16-18 s, and the time span of the load time period I' J is 25-26 s. In the subsequent step, the time segments of the intersection, namely the corresponding deleted load time segments C 'D and I' J, need to be deleted on the load spectra of the two channels.

For ease of understanding, still using the loading spectrum example of a single channel in fig. 2, assume that the loading periods AB, CD, IJ and MN are all intersections. As shown in fig. 3, after the useless load time periods AB, CD, IJ and MN in fig. 2 are deleted, the remaining load signals are connected and reconstructed by using a signal smoothing connection technique, and transition signals 301 with appropriate lengths are added at both ends of the reconstructed signals, so as to finally obtain the acceleration spectrum shown in fig. 3. The acceleration spectrum retains the amplitude and sequence of the large-amplitude payload signal 302, eliminates the payload time periods of some small payloads, and retains the time periods of small payloads at high mean.

The following specifically describes a compilation method of a multichannel load spectrum provided by the invention with reference to the accompanying drawings by taking a pull rod displacement spectrum of a front wheel and a rear wheel which are collected by a certain automobile test field and represent vertical wheel runout as an example.

FIG. 4A shows a load spectrum of vertical displacement of the left front wheel of the entire vehicle. FIG. 4B shows a load spectrum of vertical displacement of the right front wheel of the entire vehicle. Fig. 4A is a load spectrum of vertical displacement of the left front wheel acquired by a displacement sensor disposed on the front wheel tie rod. Fig. 4B is a load spectrum of vertical displacement of the right front wheel acquired by a displacement sensor disposed on the front wheel tie rod. Wherein the horizontal axis is time and the vertical axis is displacement.

FIG. 5 shows the parameter α of the pseudo-damage retention ratio of each channel as a function of the small loading threshold Ta_thA trend graph of growth. Setting parameter alpha of small load threshold Ta_thThe initial value of parameter n is 1, 0.01. As shown in the figure, the horizontal axis represents the parameter α_thThe vertical axis represents the pseudo lesion retention ratio. As the threshold range of the small load threshold Ta is expanded, each load channel includes a left front wheel load spectrum 501 and a right front wheel load spectrum 502, and the pseudo-damage retention ratio of both of them is gradually reduced. The front right wheel load spectrum 502 has a faster rate of decrease in the false damage retention ratio than the front left wheel load spectrum 501. Therefore, the pseudo-damage retention ratio of the right front wheel load spectrum 502 will first meet the preset pseudo-damage retention ratio target.

Fig. 6A is an identification diagram of the small load threshold Ta of fig. 4A under the condition that the pseudo damage retention ratio is 90%. Fig. 6B is an identification diagram of the small loading threshold Ta of fig. 4B under the condition that the pseudo damage retention ratio target is 90%. In fig. 6A and 6B, threshold ranges of the small load threshold Ta are identified.

Fig. 7A is a load spectrum for fig. 4A labeled load time period intersection for small loads. Fig. 7B is a load spectrum for fig. 4B labeled load time period intersections for small loads. In fig. 7A and 7B, the intersection of all loading periods within the threshold range of the small loading threshold Ta is marked.

Fig. 8 is an acceleration spectrum of fig. 4B under the condition that the pseudo lesion retention ratio is 90%. On the basis of fig. 7B, all load time period intersections are deleted, the time periods of the remaining load spectra after deletion are connected by using a signal smoothing technique, and transition signals with appropriate lengths are added to both ends of the signal of the reconnected load spectrum.

In summary, the multi-channel load spectrum compilation method of the present invention is used to process the load spectrum of FIG. 4B until the acceleration spectrum of FIG. 8 is obtained. The accelerometer duration is shortened to 26s, which is 45% of the corresponding load spectrum duration, and the time fluctuation history of the damage-dominated load is well preserved for the accelerometer.

FIG. 9A shows a cumulative cycle count comparison plot of the acceleration and load spectra of the left front wheel of the entire vehicle. FIG. 9B shows a cumulative cycle count comparison of the acceleration and load spectra of the right front wheel of the entire vehicle. As shown in fig. 9A and 9B, the horizontal axis represents the cumulative cycle count, the vertical axis represents the load variation, and the graphs include

dot line graphs

901 and 902 representing the original load spectrum and the acceleration spectrum, respectively. And calculating and comparing the load spectrums of the two channels of the left front wheel and the right front wheel and the rain flow cycles of the acceleration spectrums, so that for the loads with large variable ranges and medium variable ranges, the cumulative cycle count distribution of the acceleration spectrums is basically consistent with the cumulative cycle count of the original load spectrums, and the loads with large variable ranges and medium variable ranges which play a leading role in damage are completely reserved.

FIG. 10A shows a PSD analysis comparison graph of acceleration and load spectra of a left front wheel of a full vehicle. FIG. 10B shows a PSD analysis comparison graph of the acceleration spectrum and the load spectrum of the right front wheel of the entire vehicle. In both figures, the horizontal axis represents frequency and the vertical axis represents power spectral density, each figure comprising a plot of

dots

1001, 1002 representing the original load spectrum and the acceleration spectrum, respectively. It is easy to understand that from the PSD analysis of the acceleration spectrum and the original load spectrum, the load frequency range is concentrated within 30 Hz. The PSD distribution trend of the acceleration spectrum is very consistent with that of the original load spectrum, and the acceleration spectrum and the original load spectrum have PSD distribution curves with the same shape. In a partial frequency range, the energy of the acceleration spectrum is slightly higher than that of the original load spectrum, which is caused by the increase of the average vibration energy of the load spectrum due to the deletion of a large number of small load time-courses, and the frequency domain characteristics of the original load spectrum are better retained by the acceleration spectrum as a whole.

The invention also provides a computer-readable storage medium, on which a computer program is stored, which computer program, when being executed by a processor, carries out the steps of any of the programming methods described above.

Specific implementation manners and technical effects of the programming device based on the multi-channel load spectrum and the computer-readable storage medium can be found in the above embodiment of the programming method provided by the present invention, and are not described herein again.

The invention also provides a compiling method, a compiling device and a computer readable storage medium of the multichannel load spectrum, which adopt a compiling method combining a pseudo-damage retention principle and the multichannel load spectrum to compare and analyze the original load spectrum and the acceleration spectrum obtained by the compiling method from the angles of an amplitude domain and a frequency domain. The comparison result shows that the load distribution characteristics of the acceleration spectrum and the original load spectrum have consistency, and large variation range and medium variation range loads which play a leading role in damage are well reserved. The obtained acceleration spectrum well retains the frequency domain characteristics of the original load spectrum, and can replace the original load spectrum to carry out a road simulation test. From the angle of a whole vehicle four-upright-post road simulation test, the acceleration spectrum well reproduces the time domain waveform and the frequency vibration characteristic of the original load spectrum, and a good multichannel load spectrum simulation effect is achieved. From the perspective of the durability test of the whole vehicle rack, the fatigue failure position exposed on the rack is consistent with the whole vehicle durability test of a test field, and the effectiveness and the feasibility of the multi-channel load spectrum compiling method provided by the invention are verified again.

Those of skill would further appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

The various illustrative logical modules, and circuits described in connection with the embodiments disclosed herein may be implemented or performed with 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 device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In the alternative, the processor and the storage medium may reside as discrete components in a user terminal.

In one or more exemplary embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software as a computer program product, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a web site, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk (disk) and disc (disc), as used herein, includes Compact Disc (CD), laser disc, optical disc, Digital Versatile Disc (DVD), floppy disk and blu-ray disc where disks (disks) usually reproduce data magnetically, while discs (discs) reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

It will be apparent to those skilled in the art that various modifications and variations can be made to the above-described exemplary embodiments of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Claims

1. A multichannel load spectrum compiling method comprises the following steps:

s2, traversing the load spectrum, finding all load time periods according to the duration screening threshold Tt and the small load threshold Ta, calculating the intersection of the load time periods of multiple channels, deleting the time period corresponding to the intersection on the load spectrum, and connecting and reconstructing the time periods of the residual load spectrum to generate an acceleration spectrum of multiple channels;

s3, calculating and comparing the rain flow circulation of the load spectrum and the acceleration spectrum of each channel, judging whether the pseudo-damage retention proportion target is met, and if one channel is met, turning to the step S4; if all the channels do not meet the preset condition, modifying the small load threshold Ta, and turning to the step S2;

and S4, outputting the acceleration spectrum of multiple channels.

2. The programming method of claim 1, wherein finding all load time segments in step S2 comprises:

3. The programming method according to claim 1, wherein in step S1, the station of each channel is setUpper threshold value T of the small load threshold value Ta_a,up＝M+(A_max-M)·na_thSetting a lower threshold T of the small load threshold Ta_a,down＝M-(M-A_min)·na_th；

Wherein M is the mean of the load channels of the load spectrum, A_maxIs the maximum of the load path of the load spectrum, A_minIs the minimum value of the load channel of the load spectrum, parameter alpha_thThe threshold value increasing coefficient is set to be a constant, and the parameter n is a natural number.

4. The programming method according to claim 3, wherein in step S1, the parameter α is set_thThe initial value of parameter n is 1, 0.01.

5. The programming method according to claim 3, wherein in step S3, modifying the light load threshold Ta refers to modifying the parameter α_thAnd/or a parameter n to recalculate the small load threshold Ta.

6. The programming method of claim 1, wherein the operation of concatenating and reconstructing the time segments of the load spectrum of the remaining multiple passes to generate an acceleration spectrum of the multiple passes in step S2 includes concatenating the time segments of the load spectrum of the remaining multiple passes using a signal smoothing technique.

7. The programming method according to claim 6, wherein in step S2, transition signals of appropriate length are added at both ends of the reconstructed signals of the load spectrum.

8. An apparatus for multichannel load spectrum generation, comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the generation method according to any one of claims 1 to 7.

9. A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out the steps of the programming method according to any one of claims 1 to 7.