CN114659737A

CN114659737A - Modal measuring method and system and electronic equipment

Info

Publication number: CN114659737A
Application number: CN202011529084.XA
Authority: CN
Inventors: 丁明昊; 陈汝霞; 宋云峰; 刘红魏; 刘爽; 陈雪林; 张萌达; 尤凯; 鲁焕
Original assignee: Yuyao Sunny Optical Intelligence Technology Co Ltd
Current assignee: Zhejiang Shunchuang Intelligent Optical Technology Co ltd
Priority date: 2020-12-22
Filing date: 2020-12-22
Publication date: 2022-06-24
Anticipated expiration: 2040-12-22
Also published as: CN114659737B

Abstract

A mode measurement method, a mode measurement system and an electronic device can realize mode measurement with non-contact, high precision and convenient operation. The modal measurement method comprises the following steps: scanning a plurality of sampling points on the workpiece point by adjusting the relative position between the laser beam and the workpiece to be measured; acquiring vibration information of each sampling point on the workpiece to be measured by using a Doppler laser vibration measurement technology; collecting image information of the workpiece to be detected and position information of each sampling point on the workpiece to be detected; and carrying out data analysis processing on the acquired image information, the position information and the vibration information of each sampling point to output a modal model with a digital image.

Description

Modal measuring method and system and electronic equipment

Technical Field

The present invention relates to the technical field of modal analysis, and in particular, to a modal measurement method, a modal measurement system, and an electronic device.

Background

Modal analysis is an important method for researching the dynamic characteristics of a structure, and the structure can be generally described according to modal parameters such as silicon oil frequency, damping and vibration shape. With the popularization and deepening of modal analysis technology in the engineering fields of fault diagnosis, response prediction, structure optimization design and the like, the demands of industries such as machinery, automobiles, aerospace, precision manufacturing, civil engineering and the like on the modal analysis technology are increasingly urgent. Since the modal parameters required for modal analysis are often determined by data obtained through experimental modal analysis, a simple-to-operate and high-precision experimental modal measurement technique becomes a key for modal analysis.

The traditional test mode measurement system mainly comprises an excitation system, a detection system and a data analysis system. Firstly, generating a formulated excitation signal through an excitation system to enable a workpiece to be detected to generate mechanical vibration; secondly, acquiring vibration signals fed back by a plurality of sampling points uniformly distributed on the workpiece to be detected through a detection system; finally, the excitation signal and the vibration signal are synchronously transmitted to a data analysis system in real time so as to be processed into data such as natural frequency, damping, vibration shape and the like which can be used for modal analysis by engineering technicians through calculation.

However, in the process of acquiring a vibration signal, the conventional test mode measurement system has to stick a sensor (i.e., a detection system) for data acquisition to a detected workpiece, that is, the sensor and the detected workpiece contact each other to complete a corresponding detection task, so that if the detected workpiece is a large cross-space structure, the problem of unchanged installation of the acceleration sensor exists; if the weight of the workpiece to be detected is light, the detected data is easily influenced by the quality of the sensor to generate larger errors; more troublesome is that if the dimension of the measured workpiece is in the micro-nano dimension, the conventional contact sensor cannot be mounted on the measured workpiece at all, and cannot acquire a corresponding vibration signal, which greatly limits the application field and range of the conventional test mode measurement system.

In addition, even if the vibration signal of the workpiece to be measured can be collected, the conventional test mode measurement technology has some inconvenient problems, such as: 1) the data collected by the sensors distributed on the workpiece to be measured need to be imported into a data analysis system one by one, which is time-consuming and labor-consuming; 2) because the position data of the sensors distributed on the measured workpiece cannot be extracted, and the positions of the sensors can only be input into the data analysis system manually and roughly, once the distribution of the sensors is not uniform or the input of the position information is not accurate, the modal model finally output by the data analysis system may generate large deviation; 3) the traditional test mode measurement technology is blank in analysis of the dynamic characteristics of the complex workpiece, namely the traditional test mode measurement technology cannot analyze the dynamic characteristics of the complex workpiece at all.

Disclosure of Invention

An advantage of the present invention is to provide a modal measurement method, a system thereof, and an electronic device, which can implement a non-contact type, high-precision, and convenient modal measurement.

Another advantage of the present invention is to provide a modal measurement method, a system thereof, and an electronic device, wherein in an embodiment of the present invention, the modal measurement method can accurately acquire a vibration signal of a workpiece to be measured, such as a workpiece with a lighter mass or a workpiece with a micro-nano scale, by using a laser doppler vibration measurement technology without using a contact sensor, which is beneficial to improving measurement accuracy and expanding an application range.

Another advantage of the present invention is to provide a modal measurement method, a system and an electronic device thereof, wherein in an embodiment of the present application, the modal measurement method can sequentially distribute laser spots on each sampling point on the workpiece to be measured, so as to implement non-contact modal measurement.

Another advantage of the present invention is to provide a modal measurement method, a system and an electronic device thereof, wherein in an embodiment of the present application, the modal measurement method can collect image information of a workpiece to be measured and position information of sampling points while collecting vibration information of the workpiece to be measured, so as to perform modal analysis on dynamic characteristics of a complex workpiece, which solves a gap in the conventional experimental modal measurement technology.

Another advantage of the present invention is to provide a modal measurement method, a system and an electronic device thereof, wherein in an embodiment of the present application, the modal measurement method can implement the required modal measurement by fusing a laser scanning vibration measurement and a digital image, which is helpful to improve measurement accuracy, simplify operation complexity and expand the application range of modal measurement technology.

Another advantage of the present invention is to provide a modal measurement method, a system and an electronic device thereof, wherein in an embodiment of the present invention, the modal measurement method can integrate the image capturing unit, the vibration measuring unit and the scanning unit into a same device, so as to improve the compactness of the corresponding system, reduce the overall volume of the system, and simplify the measurement operation.

Another advantage of the present invention is to provide a modal measurement method, a system and an electronic device thereof, wherein it is not necessary to use expensive materials or complicated structures in the present invention in order to achieve the above objects. Therefore, the present invention successfully and effectively provides a solution to not only provide a simple modal measurement method and system thereof, but also increase the practicality and reliability of the modal measurement method and system thereof, and electronic device.

To achieve at least one of the above advantages or other advantages or objects, the present invention provides a modal measurement method, including:

scanning a plurality of sampling points on the workpiece point by adjusting the relative position between the laser beam and the workpiece to be measured;

acquiring vibration information of each sampling point on the workpiece to be measured by using a Doppler laser vibration measurement technology;

collecting image information of the workpiece to be detected and position information of each sampling point on the workpiece to be detected; and

and carrying out data analysis processing on the acquired image information, the position information and the vibration information of each sampling point so as to output a modal model with a digital image.

According to an embodiment of the present application, the step of scanning the plurality of sampling points on the measured workpiece point by adjusting the relative position between the laser beam and the measured workpiece includes the steps of:

according to the measurement requirement, a plurality of sampling points are distributed on the measured workpiece; and

the laser beam is deflected in an angle-adjustable manner so as to gradually change the propagation angle of the laser beam, so that the deflected laser beam propagates to a plurality of sampling points on the measured workpiece point by point.

According to an embodiment of the present application, the step of deflecting the laser beam with an adjustable angle to gradually change the propagation angle of the laser beam, so that the deflected laser beam propagates to a plurality of sampling points on the workpiece point by point includes the steps of:

reflecting the laser beam through a reflective vibrating mirror so as to enable the laser beam to be transmitted to a current sampling point on the workpiece to be measured; and

and reflecting the laser beam again by adjusting the reflection angle of the reflective vibrating mirror so as to enable the laser beam to be transmitted to the next sampling point on the workpiece to be measured.

refracting the laser beam through a refraction type prism so as to enable the laser beam to be transmitted to the current sampling point on the measured workpiece; and

the laser beam is refracted again by rotating the refraction type prism so as to be transmitted to the next sampling point of the workpiece to be measured.

According to an embodiment of the present application, the step of acquiring the image information of the measured workpiece and the position information of each sampling point on the measured workpiece includes the steps of:

shooting the picture of the workpiece to be measured to obtain a digital image corresponding to the workpiece to be measured;

calibrating the position of the workpiece to be detected in the digital image; and

and positioning the position of the current sampling point on the measured workpiece in the digital image.

According to an embodiment of the present application, the step of scanning the plurality of sampling points on the workpiece point by adjusting the relative position between the laser beam and the workpiece to be measured includes the steps of:

and gradually moving the position of the workpiece to be measured so that the laser beam propagates to a plurality of sampling points on the workpiece to be measured point by point.

arranging a part of reflection and transmission element in a light path of the laser beam transmitted to the current sampling point on the workpiece to be tested;

shooting pictures of the workpiece to be detected before and after movement through the partial transflective element so as to obtain digital images corresponding to the workpiece to be detected before and after movement; and

and determining the position of the current sampling point on the workpiece to be tested.

According to an embodiment of the present application, the step of acquiring vibration information at each sampling point on the workpiece to be measured by using the doppler laser vibration measurement technology includes the steps of:

emitting the laser beam to be reflected by the current sampling point on the workpiece to be measured to form a laser echo; and

and receiving the laser echo to acquire displacement data at the current sampling point on the workpiece to be detected.

According to an embodiment of the present application, the step of performing data analysis processing on the acquired image information and the position information and the vibration information of each sampling point to output a modal model with a digital image includes the steps of:

fourier transform processing is carried out on the displacement data at each of the collected sampling points to obtain a corresponding response function;

carrying out normalization processing on the response function to obtain a corresponding amplitude-frequency curve;

carrying out three-dimensional visual transformation on the vibration amplitude corresponding to the extreme point on the amplitude-frequency curve to obtain a modal model corresponding to the extreme point; and

and fusing the modal model to the digital image according to the position information of each sampling point to obtain the modal model with the digital image.

According to an embodiment of the present application, the modal measurement method further includes the steps of:

and acquiring an excitation signal of the workpiece to be detected, and carrying out phase synchronization on the excitation signal and the vibration signal of each sampling point on the workpiece to be detected so as to output data for modal analysis.

According to an embodiment of the present application, the step of obtaining the excitation signal of the workpiece to be measured to perform phase synchronization between the excitation signal and the vibration signal of each sampling point on the workpiece to be measured, so as to output the bode plot of each sampling point on the workpiece to be measured includes the steps of:

applying the excitation signal to the workpiece to be measured so as to excite the workpiece to be measured to generate mechanical vibration; and

the excitation signal applied to the workpiece to be measured is collected to be processed with the vibration signal into a bode plot of each sampling point on the workpiece to be measured.

According to another aspect of the present application, the present application further provides a modal measurement system for performing modal measurement on a workpiece to be measured, wherein the modal measurement system comprises:

a measurement system, wherein the measurement system comprises communicatively coupled to each other:

the adjusting unit is used for scanning a plurality of sampling points on the workpiece to be detected point by adjusting the relative position between the laser beam and the workpiece to be detected;

the vibration measuring unit is used for acquiring vibration information of each sampling point on the measured workpiece by using a Doppler laser vibration measuring technology; and

the image acquisition unit is used for acquiring the image information of the workpiece to be detected and the position information of each sampling point on the workpiece to be detected; and

and the data analysis system is used for carrying out data analysis processing on the acquired image information and the position information and the vibration information of each sampling point so as to output a modal model with a digital image.

According to an embodiment of the application, the adjusting unit comprises a layout module and a deflection module, wherein the layout module is used for laying a plurality of sampling points on the measured workpiece according to the measurement requirement; the deflection module is used for deflecting the laser beam in an angle-adjustable manner so as to gradually change the propagation angle of the laser beam, so that the deflected laser beam propagates to a plurality of sampling points on the measured workpiece point by point.

According to an embodiment of the application, the image acquisition unit comprises a camera module, a calibration module and a positioning module, wherein the camera module is used for shooting a picture of the workpiece to be tested so as to obtain a digital image corresponding to the workpiece to be tested; the calibration module is used for calibrating the position of the workpiece to be measured in the digital image; the positioning module is used for positioning the position of the current sampling point on the measured workpiece in the digital image.

According to an embodiment of the application, the adjusting unit comprises a layout module and a moving module, wherein the layout module is used for laying a plurality of sampling points on the measured workpiece according to the measurement requirement; the moving module is used for gradually moving the position of the workpiece to be measured, so that the laser beam is transmitted to a plurality of sampling points on the workpiece to be measured point by point.

According to an embodiment of the present application, the image capturing unit includes a setting module, a camera module and a positioning module, wherein the setting module is configured to set a part of the anti-reflection element in a light path of the laser beam propagating to a current sampling point on the workpiece to be tested; the camera module is used for shooting pictures of the workpiece to be measured before and after movement through the partial transflective element so as to obtain digital images corresponding to the workpiece to be measured before and after movement; the positioning module is used for determining the position of the current sampling point on the workpiece to be tested.

According to an embodiment of the application, the vibration measuring unit comprises a transmitting module and a receiving module, wherein the transmitting module is used for transmitting the laser beam to be reflected by a current sampling point on the measured workpiece to form a laser echo; the receiving module is used for receiving the laser echo to acquire displacement data at the current sampling point on the workpiece to be measured.

According to an embodiment of the application, the data analysis system comprises a fourier transform module, a normalization processing module, a visualization conversion module and a fusion module which are mutually connected in a communication manner, wherein the fourier transform module is used for performing fourier transform processing on the displacement data at each acquired sampling point to obtain a corresponding response function; the normalization processing module is used for performing normalization processing on the response function to obtain a corresponding amplitude-frequency curve; the visual conversion module is used for performing three-dimensional visual conversion on the vibration amplitude corresponding to the extreme point on the amplitude-frequency curve so as to obtain a modal model corresponding to the extreme point; the fusion module is used for fusing the modal model to the digital image according to the position information of each sampling point so as to obtain the modal model with the digital image.

According to an embodiment of the present application, the modal measurement system further includes an excitation system, where the excitation system is configured to obtain an excitation signal of the workpiece to be measured, so as to perform phase synchronization between the excitation signal and a vibration signal of each sampling point on the workpiece to be measured, so as to output data for modal analysis.

According to another aspect of the present application, the present application further provides an electronic device comprising:

at least one processor configured to execute instructions; and

a memory communicatively coupled to the at least one processor, wherein the memory has at least one instruction, wherein the instruction is executable by the at least one processor to cause the at least one processor to perform all or a portion of the steps of a modal measurement method, wherein the modal measurement method comprises the steps of:

According to another aspect of the present application, the present application further provides an electronic device for performing modal measurement on a workpiece under test, wherein the electronic device comprises:

a measurement system, wherein the measurement system comprises:

a camera unit;

a vibration measuring unit;

an adjustment unit; and

the control unit is respectively connected with the camera unit, the vibration measuring unit and the adjusting unit in a communication mode and is used for controlling the camera unit to acquire image information of the workpiece to be measured, controlling the vibration measuring unit to acquire vibration information of the workpiece to be measured by using a Doppler laser vibration measuring technology and controlling the adjusting unit to adjust the relative position between a laser beam emitted by the vibration measuring unit and the workpiece to be measured so that the laser beam emitted by the vibration measuring unit scans a plurality of sampling points on the workpiece point by point; and

a data analysis system, wherein the data analysis system is communicatively connected to the measurement system 71 for performing data analysis processing on the acquired image information and the vibration information to output a modal model with a digital image.

According to an embodiment of the present application, the adjusting unit of the measuring system is a scanning unit, wherein the scanning unit is under the control of the control unit, and is configured to convert a laser beam emitted by an existing vibration measuring unit into scanning laser according to a requirement of calibration scanning by using a reflective galvanometer or a refractive prism, so as to perform calibration scanning on the workpiece to be measured.

According to an embodiment of the application, the scanning unit, the vibration measuring unit and the camera unit in the measuring system are integrated into the same device.

According to an embodiment of the present application, the adjusting unit of the measuring system is a moving unit, wherein the moving unit is configured to move the workpiece to be measured one by one, so that the laser beam emitted by the vibration measuring unit propagates to a plurality of sampling points on the workpiece one by one.

According to an embodiment of the present application, the measuring system further includes a reflection unit, wherein the reflection unit is disposed in a laser optical path between the vibration measuring unit and the workpiece to be measured, and is configured to reflect visible light from the workpiece to be measured to be received by the camera unit to obtain digital images corresponding to the workpiece to be measured before and after being moved.

According to an embodiment of the application, the data analysis system comprises a calibration scanning unit, a data acquisition unit and an analysis modeling unit which are mutually connected in a communication way, wherein the calibration scanning unit is used for calibrating the position relation between the camera unit and the vibration measurement unit according to the test requirement, and enabling the laser beam emitted by the vibration measurement unit to carry out point-by-point scanning on the workpiece to be tested according to the preset sampling point position in the digital image acquired by the camera unit; the data acquisition unit is used for acquiring image information and position information of each sampling point acquired by the camera unit and acquiring vibration information of each sampling point acquired by the vibration measurement unit; the analysis modeling unit is used for carrying out data analysis processing on the acquired image information, the position information of each sampling point and the vibration information so as to output a modal model with a digital image.

According to an embodiment of the present application, the electronic device further includes an excitation system, wherein the excitation system is configured to apply an excitation vibration to the workpiece to be tested, and the excitation system is communicatively connected to the data analysis system, wherein the data analysis system is configured to obtain an excitation signal from the excitation system, so as to synchronize the excitation signal with a phase of the vibration signal at each sampling point on the workpiece to be tested, so as to output data for modal analysis.

Further objects and advantages of the invention will be fully apparent from the ensuing description and drawings.

These and other objects, features and advantages of the present invention will become more fully apparent from the following detailed description, the accompanying drawings and the claims.

Drawings

Fig. 1 is a flow chart of a modal measurement method according to an embodiment of the present application.

Fig. 2 shows a flow chart of the adjustment steps of the modal measurement method according to the above-described embodiment of the present application.

Fig. 3A shows an example of the adjusting step of the modal measurement method according to the above-described embodiment of the present application.

Fig. 3B shows another example of the adjusting step of the modal measurement method according to the above-described embodiment of the present application.

Fig. 4 shows a flow chart of the vibration acquisition step of the mode shape measurement method according to the above-described embodiment of the present application.

Fig. 5 shows a flow chart of the image acquisition steps of the modality measurement method according to the above-described embodiment of the present application.

Fig. 6 shows a flow chart of the data analysis step of the modal measurement method according to the above-described embodiment of the present application.

Fig. 7 shows a flow chart of the excitation step of the modal measurement method according to the above-described embodiment of the present application.

Fig. 8 is a schematic diagram of a workpiece to be measured in the modal measurement method according to the embodiment of the present application.

Fig. 9 shows a schematic diagram of a distribution of sampling points in the modal measurement method according to the above-described embodiment of the present application.

Fig. 10 shows an example of a bode plot in the modal measurement method according to the above-described embodiment of the present application.

Fig. 11A shows a schematic diagram of mode shape contrast at 1823Hz in the modal measurement method according to the above-described embodiment of the present application.

Fig. 11B shows a schematic diagram of mode shape comparison at 2627Hz in the modal measurement method according to the above-described embodiment of the present application.

Fig. 12 shows an example of a modal model with digital images in the modal measurement method according to the above-described embodiment of the present application.

Fig. 13 shows a variant implementation of the adjustment step in the modal measurement method according to the above-described embodiment of the present application.

Fig. 14 shows a variant implementation of the image acquisition step in the modality measurement method according to the above-described embodiment of the present application.

Fig. 15 is a block diagram schematic diagram of a modal measurement system according to an embodiment of the present application.

Fig. 16 is a variant implementation of the modal measurement system according to the above-described embodiment of the present application.

Fig. 17 shows a block diagram schematic of an electronic device according to a first embodiment of the application.

Fig. 18 shows a block diagram schematic of an electronic device according to a second embodiment of the application.

Fig. 19A shows an integrated schematic diagram of a measurement system in the electronic device according to the above-described second embodiment of the present application.

Fig. 19B shows an example of a control unit in the electronic apparatus according to the above-described second embodiment of the present application.

Fig. 20A shows a schematic view of the electronic device according to the above-described second embodiment of the present application.

Fig. 20B shows a schematic view of the electronic device according to the above-described variant embodiment of the present application.

Detailed Description

The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art. The basic principles of the invention, as defined in the following description, may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the invention.

It will be understood by those skilled in the art that in the present disclosure, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for ease of description and simplicity of description, and do not indicate or imply that the referenced devices or components must be constructed and operated in a particular orientation and thus are not to be considered limiting.

In the present invention, the terms "a" and "an" in the claims and the description should be understood as meaning "one or more", that is, one element may be one in number in one embodiment, and the element may be more than one in number in another embodiment. The terms "a" and "an" should not be construed as limiting the number unless the number of such elements is explicitly recited as one in the present disclosure, but rather the terms "a" and "an" should not be construed as being limited to only one of the number.

Modal analysis is an important method for researching the dynamic characteristics of a structure, and the structure can be generally described according to modal parameters such as silicon oil frequency, damping and vibration shape. Because the modal parameters required by modal analysis are often determined through data obtained through the test modal analysis, and a traditional test modal measurement system has to paste a sensor (namely, a detection system) for data acquisition onto a measured workpiece in the process of acquiring a vibration signal, that is, the sensor and the measured workpiece are contacted with each other to finish a corresponding detection task, if the measured workpiece is a large cross-space structure, the problem that the installation of an acceleration sensor is unchanged exists; if the weight of the workpiece to be detected is light, the detected data is easily influenced by the quality of the sensor to generate larger errors; more troublesome is that if the dimension of the measured workpiece is in the micro-nano dimension, the conventional contact sensor cannot be mounted on the measured workpiece at all, and cannot acquire a corresponding vibration signal, which greatly limits the application field and range of the conventional test mode measurement system.

In addition, even if the vibration signal of the workpiece to be measured can be collected, the conventional test mode measurement technology has some inconvenient problems, such as: 1) the data collected by the sensors distributed on the workpiece to be measured need to be imported into a data analysis system one by one, which is time-consuming and labor-consuming; 2) because the position data of the sensors distributed on the measured workpiece cannot be extracted, and the positions of the sensors can only be input into the data analysis system manually and roughly, once the distribution of the sensors is not uniform or the input of the position information is not accurate, the modal model finally output by the data analysis system may generate large deviation; 3) the traditional test mode measurement technology is blank in the analysis of the dynamic characteristics of the complex workpiece, namely the traditional test mode measurement technology cannot analyze the dynamic characteristics of the complex workpiece at all.

Therefore, in order to solve the above problems, the present application provides a modal measurement method, a system thereof, and an electronic device, which can perform non-contact, high-precision, and convenient-to-operate test modal measurement on a workpiece to be measured in a mode of fusing laser scanning vibration measurement and a digital image, and are helpful to expand the application range of the modal measurement method, the system thereof, and the electronic device.

Illustrative method

Referring to fig. 1-7 of the drawings, a modal measurement method for performing modal measurements on a workpiece under test is illustrated according to an embodiment of the present invention. Specifically, as shown in fig. 1, the modal measurement method may include the steps of:

s100: scanning a plurality of sampling points on the workpiece point by adjusting the relative position between the laser beam and the workpiece to be measured;

s200: acquiring vibration information of each sampling point on the workpiece to be measured by using a Doppler laser vibration measurement technology;

s300: collecting image information of the workpiece to be detected and position information of each sampling point on the workpiece to be detected; and

s400: and carrying out data analysis processing on the acquired image information, the position information and the vibration information of each sampling point so as to output a modal model with a digital image.

It is worth noting that, because the mode measurement method of the application utilizes the doppler laser vibration measurement technology to perform non-contact type acquisition on the vibration information of each sampling point on the measured workpiece, and does not need to stick a contact type sensor to the measured workpiece, the mode measurement method of the application can break through the user convenience of the traditional test mode measurement method, and thoroughly solves many defects of the traditional test mode measurement method. Meanwhile, the modal measurement method can also acquire the image information of the measured workpiece and the position information of each sampling point (namely the position information of the laser spot on the measured workpiece during laser vibration measurement every time) so as to avoid the generation of larger deviation of an output modal model due to inaccurate position information. In particular, since the modal measurement method of the present application can synchronize image information of a workpiece to be measured into a modal model to output the modal model with a digital image for performing dynamic characteristic analysis of individual features in the workpiece to be measured, the modal measurement method of the present application can analyze dynamic characteristics of a complex workpiece to be measured to make up for a gap existing in this point of a conventional experimental modal measurement technology.

More specifically, as shown in fig. 2, the step S100 of the modal measurement method according to the above embodiment of the present application may include the steps of:

s110: according to the measurement requirement, a plurality of sampling points are distributed on the measured workpiece; and

s120: the laser beam is deflected in an angle-adjustable manner so as to gradually change the propagation angle of the laser beam, so that the deflected laser beam propagates to a plurality of sampling points on the measured workpiece point by point.

It should be noted that the measurement requirements mentioned in the present application can be determined according to the size of the workpiece to be measured and the mode shape to be measured. In particular, the plurality of sampling points on the workpiece under test may have different distribution forms, such as a rectangular distribution, a concentric circle distribution, a random distribution, and the like. It is understood that, in the above embodiments of the present application, the modal measurement method may deflect the laser beam to form a scanning laser according to the requirement of the calibration scan, thereby implementing the calibration scan on the workpiece to be measured.

Illustratively, in an example of the present application, as shown in fig. 3A, the step S120 of the modal measurement method may include the steps of:

s121: reflecting the laser beam through a reflective vibrating mirror so as to enable the laser beam to be transmitted to a current sampling point on the workpiece to be measured; and

s122: and reflecting the laser beam again by adjusting the reflection angle of the reflective vibrating mirror so as to enable the laser beam to be transmitted to the next sampling point on the workpiece to be measured.

Of course, in another example of the present application, as shown in fig. 3B, the step S120 of the modal measurement method may also include the steps of:

s123: refracting the laser beam through a refraction type prism so as to enable the laser beam to be transmitted to a current sampling point on the workpiece to be tested; and

s124: the laser beam is refracted again by rotating the refraction type prism so as to be transmitted to the next sampling point on the measured workpiece.

According to the above embodiment of the present application, as shown in fig. 4, the step S200 of the modal measurement method may include the steps of:

s210: emitting the laser beam to be reflected by the current sampling point on the workpiece to be measured to form a laser echo; and

s220: and receiving the laser echo to acquire displacement data at the current sampling point on the workpiece to be measured.

It should be noted that, while collecting the vibration information of the current sampling point, as shown in fig. 5, the step S300 of the modal measurement method of the present application may include the steps of:

s310: shooting the picture of the workpiece to be measured to obtain a digital image corresponding to the workpiece to be measured;

s320: calibrating the position of the workpiece to be detected in the digital image; and

s330: and positioning the position of the current sampling point on the measured workpiece in the digital image.

It should be noted that, in the modal measurement method of the present application, the sequence among the step S100, the step S200, and the step S300 may be not sequential, or may be performed alternately, as long as the required image information, and the position information and the vibration information of each sampling point can be acquired.

Further, as shown in fig. 6, the step S400 of the modal measurement method of the present application may include the steps of:

s410: carrying out Fourier transform processing on the collected displacement data at each sampling point to obtain a corresponding response function;

s420: carrying out normalization processing on the response function to obtain a corresponding amplitude-frequency curve;

s430: carrying out three-dimensional visual transformation on the vibration amplitude corresponding to the extreme point on the amplitude-frequency curve to obtain a modal model corresponding to the extreme point; and

s440: and fusing the modal model to the digital image according to the position information of each sampling point to obtain the modal model with the digital image.

It is worth mentioning that the mode measurement method of the present application may directly perform test mode measurement or working mode measurement on the workpiece having self-excited vibration, or may perform working mode measurement on the workpiece not having self-excited vibration, because the workpiece does not need to additionally apply an excitation signal during working or self-excited vibration. Of course, when performing test mode measurement on the workpiece, whether the workpiece has self-excited vibration or not, it is necessary to acquire an excitation signal (self-excited signal or external excited signal) of the workpiece, and therefore, as shown in fig. 1, the mode measurement method of the present application may further include the steps of:

s500: and acquiring an excitation signal of the workpiece to be detected, and carrying out phase synchronization on the excitation signal and the vibration signal of each sampling point on the workpiece to be detected so as to output data for modal analysis.

In particular, when performing a test mode measurement on the workpiece without self-excited vibration, an excitation system is additionally provided to apply an excitation signal to the workpiece, in other words, as shown in fig. 7, the step S500 of the mode measurement method of the present application may include the steps of:

s510: applying the excitation signal to the workpiece to be measured so as to excite the workpiece to be measured to generate mechanical vibration; and

s520: the excitation signal applied to the workpiece to be measured is collected to be processed with the vibration signal into a bode plot of each sampling point on the workpiece to be measured.

It is to be noted that, in the step S510 of the modal measurement method of the present application, the excitation signal may be divided into: a pulsed excitation signal, a step relaxation excitation signal, a random excitation signal, and a forward scan excitation signal, among others.

The pulse excitation signal is realized by mainly utilizing a pulse hammer to switch the pulse frequency spectrum width by replacing the hammer head material, the excitation mode has the characteristics of rapidness and convenience, and has no additional rigidity constraint on the workpiece to be detected, but because the energy is dispersed in a very wide frequency band, the excitation energy is small, and therefore if the workpiece to be detected is larger, a better signal-to-noise ratio cannot be obtained, and the parameter acquisition fails.

The step relaxation excitation mode is to apply a force at an excitation point in advance to deform the workpiece, and then suddenly remove the force to enable the workpiece to be tested to emit excitation, but the excitation mode has a large low-frequency component and is usually used for exciting a structure with a very low natural frequency to acquire a low-order mode.

The random and sinusoidal scanning excitation mode is to use an excitation system composed of a signal source, a power amplifier and a vibration exciter to carry out excitation, that is, the signal source generates a required random or sinusoidal signal, and the random or sinusoidal signal is amplified by the power amplifier to power capable of driving the vibration exciter, so that an electrical signal is converted into mechanical vibration to excite the tested workpiece. The excitation energy of the excitation mode is concentrated, and the method has the characteristics of large signal-to-noise ratio and high test precision.

In summary, the above excitation methods have advantages and disadvantages, and have respective application occasions; and meanwhile, the excitation method can be mutually supplemented so as to excite the workpiece to be tested by using a plurality of excitation modes in the same test.

Illustratively, as shown in fig. 8, an aluminum plate having dimensions of 110mm long, 54mm wide, and 2.4mm thick and being AL6061 in material is used as the workpiece to be measured, and is excited with a sinusoidal scanning excitation signal for obtaining a bode diagram of the aluminum plate and a mode shape of the workpiece in a selected spectral range.

Specifically, first, a signal generator is used to generate the required excitation signal, which has the setting parameters of 10Vpp, sweep frequency mode of 0-20kHz, and sweep time of 1 s. It can be understood that, since the size of the aluminum plate is small in this example, the excited actuator uses the piezoelectric element to perform the conversion of the electrical signal and the mechanical vibration, and the excitation signal output by the signal generator can satisfy the driving condition of the piezoelectric element, the signal generator is not required to perform the electrical signal amplification in this example. Of course, in other examples of the present application, the electrical signal of the excitation source (i.e., the signal generator) may be amplified according to actual conditions to meet the driving requirements of the actuator.

Secondly, the excitation signal generated by the signal generator can be synchronously transmitted to a data analysis system for phase synchronization of the data analysis system, and finally, the frequency response function of the measured workpiece is output to draw a Bode diagram. Of course, in practical applications, if the excitation signal cannot be directly transmitted to the data analysis system, an oscillation measuring unit may be added, and a laser spot of the oscillation measuring unit is located on the driving surface of the actuator, so as to detect the oscillation information of the driving surface of the actuator and acquire the oscillation signal of the driving surface, thereby indirectly acquiring the excitation signal and synchronizing the excitation signal to the data analysis system.

Thereafter, since the workpiece to be measured in this example is a rectangular part, the distribution of the multiple sampling points on the workpiece to be measured takes the form of rectangular distribution, such as a 15 × 10 rectangular array (as shown in fig. 9) distributed on the surface of the workpiece to be measured. Of course, in other examples of the present application, the modal measurement method of the present application may also adopt a distribution form, such as a concentric circle distribution or a random distribution, to perform distribution of sampling points according to measurement requirements, which is not described in detail herein.

It should be noted that if the test range greatly exceeds the scanning range of the device or the outer contour of the workpiece to be tested is a less flat surface such as a cylindrical surface or a spherical surface, scanning can be performed at different positions or directions of the workpiece to be tested, so as to finally splice the modal models together. In addition, since the maximum frequency of the excitation signal frequency sweep is 20kHz in this example, in order to acquire a good waveform, the sampling frequency needs to be 50kHz or more when acquiring the signal, and the number of spectral lines should be 50000 or more when the mode analysis software performs FFT operation. And if the modal shape of the measured workpiece in other frequency bands needs to be analyzed, the sampling frequency and the FFT spectral line number also need to be correspondingly adjusted.

Finally, after calibration and stationing are completed, modal analysis softwareScanning the laser beam of the vibration measuring unit point by point and sampling vibration information according to a 15 multiplied by 10 rectangular array; meanwhile, the excitation signal of the excitation source is synchronously acquired at the moment, and is used for calculating the frequency response curve of each sampling point and synchronizing the phase information of the Bode diagram. For example, displacement data v of each sampling point obtained by sampling by the vibration unit_j,k(t) (wherein j is the row number of the sampling point, k is the column number of the sampling point), the collected excitation signal is the excitation data m (t), and the Fourier transform data is respectively carried out on the excitation data m (t) and the excitation data m (t) to convert the Fourier transform data into V_j，k(ω) and M (ω) having a frequency response function of:

H_j,k(jω)＝V_j，k(ω)/M(t)

thus, after the frequency response function is normalized, the following results can be obtained: h_j,k(jω)＝1/(τjω+1)

Due to H_j,k(j ω) is a complex number that can be divided into amplitude and phase, where the amplitude-frequency curve is: a. the_j,k(ω)＝∣H_j,k(j ω) |; phase frequency curve is phi_j,k(ω) — arctan (ω τ); therefore, if the two curves take the form of logarithmic coordinates, the corresponding output is the Bode diagram (the Bode diagram shown in fig. 10).

It is understood that a common observation of modal analysis is a modal model corresponding to an extremum point on the amplitude-frequency curve. That is, after the data is subjected to fourier transform, the vibration amplitude D corresponding to the extreme point on the amplitude-frequency curve is taken_j,kAnd performing three-dimensional visual conversion on the data by using modal analysis software to obtain a modal model corresponding to the extreme point. For example, in the present example, the amplitude data of the 2 nd (corresponding to a frequency of 1823Hz) and 4 th (corresponding to a frequency of 2627Hz) extreme points may be taken, respectively. Particularly, a modal model is generated in modal analysis software, and mode shape comparison is performed in a finite element simulation mode (as shown in fig. 11A and 11B), so that it can be seen that the modal mode shape obtained by the method is basically consistent with the simulation result, and the method can be used as a modal measurement method with convenient operation and accurate measurement.

In addition, the digital image of the workpiece to be measured can be obtained during scanning calibration, and the positions of the sampling points of the digital image are in one-to-one correspondence with the positions of the nodes of the modal model, so that the modal model fused with the digital image can be observed in the forward view of the modal model (as shown in fig. 12). Meanwhile, even if the tested workpiece has more complex characteristics and needs targeted analysis, the modal model with the digital image can meet the requirements.

It should be noted that, for a workpiece with a micro-nano size, it is difficult to propagate to multiple sampling points on the workpiece point by deflecting the angle of the laser beam, because the dimension of the workpiece is in the micro-nano level, and slightly deflecting the angle of the laser beam will cause the laser beam to deviate from the workpiece, and the multiple sampling points on the workpiece cannot be scanned point by point. Therefore, in order to solve the above problem, in a modified embodiment of the mode shape measurement method of the present application, as shown in fig. 13A, the step S100 of the mode shape measurement method may include the steps of:

s110': according to the measurement requirement, a plurality of sampling points are distributed on the measured workpiece; and

s120': and gradually moving the position of the workpiece to be measured so that the laser beam propagates to a plurality of sampling points on the workpiece to be measured point by point.

Similarly, since the distance between adjacent sampling points in the workpiece to be measured is also in the micro-nano level, it is difficult to accurately determine the position of each sampling point by directly shooting the picture of the workpiece to be measured with a camera, and therefore, in order to solve this problem, as shown in fig. 13B, the step S300 of the modal measurement method in this modified embodiment of the present application may also include the steps of:

s310': arranging a part of reflection and transmission element in a light path of the laser beam transmitted to the current sampling point on the workpiece to be tested;

and S320': shooting pictures of the workpiece to be detected before and after movement through the partial transflective element so as to obtain digital images corresponding to the workpiece to be detected before and after movement; and

s330': and determining the position of the current sampling point on the workpiece to be tested.

It should be noted that the partially reflective and semi-transmissive element may be implemented as a semi-reflective and semi-transmissive mirror, or as an optical element that transmits the laser beam and reflects visible light, which is not described in detail herein.

Illustrative System

According to another aspect of the present invention, in order to better implement the above mode measurement method to accurately perform mode measurement on a workpiece to be measured, the present invention further provides a mode measurement system. According to an embodiment of the present invention, as shown in fig. 14, the modal measurement system 60 includes a measurement system 61 and a data analysis system 62 communicatively connected to each other. The measurement system 61 comprises, communicatively connected to each other: an adjusting unit 611, configured to perform point-by-point scanning on the multiple sampling points on the workpiece to be measured by adjusting a relative position between the laser beam and the workpiece to be measured; a vibration measurement unit 612, configured to collect vibration information at each sampling point on the workpiece to be measured by using a doppler laser vibration measurement technique; and an image collecting unit 613, configured to collect image information of the workpiece to be tested and position information of each sampling point on the workpiece to be tested. The data analysis system 62 is configured to perform data analysis processing on the acquired image information and the position information and the vibration information of each sampling point to output a modal model with a digital image.

It should be noted that, in the above embodiment of the present application, as shown in fig. 14, the adjusting unit 611 may include a layout module 6111 and a deflection module 6112, where the layout module 6111 is configured to lay a plurality of sampling points on the measured workpiece according to the measurement requirement; the deflecting module 6112 is configured to deflect the laser beam with an adjustable angle, so as to gradually change the propagation angle of the laser beam, so that the deflected laser beam propagates to multiple sampling points on the workpiece point by point.

Correspondingly, as shown in fig. 14, the image acquiring unit 613 may include a camera module 6131, a calibration module 6132 and a positioning module 6133, where the camera module 6131 is configured to capture a picture of the workpiece to be tested, so as to obtain a digital image corresponding to the workpiece to be tested; the calibration module 6132 is used to calibrate the position of the workpiece to be measured in the digital image; the positioning module 6133 is used to position the current sampling point on the workpiece under test in the digital image.

However, fig. 15 shows a variant implementation of the electronic device 60 according to the above-described embodiment of the present application, which differs in that: the adjusting unit 611 may also include a layout module 6111 ' and a moving module 6112 ', wherein the layout module 6111 ' is configured to layout a plurality of sampling points on the workpiece to be measured according to the measurement requirement; the moving module 6112' is configured to move the position of the workpiece to be measured one by one, so that the laser beam propagates to the sampling points on the workpiece point by point.

Correspondingly, as shown in fig. 15, the image collecting unit 613 may also include a setting module 6131 ', a camera module 6132', and a positioning module 6133 ', where the setting module 6131' is used to set a part of the reflective element in the light path of the laser beam propagating to the current sampling point on the workpiece to be tested; the camera module 6132' is used for shooting the pictures of the workpiece to be tested before and after moving through the partial transflective element to obtain digital images corresponding to the workpiece to be tested before and after moving; the positioning module 6133' is used to determine the position of the current sampling point on the workpiece to be tested.

According to the above embodiment of the present application, as shown in fig. 14, the vibration measuring unit 612 includes a transmitting module 6121 and a receiving module 6122, where the transmitting module 6121 is configured to transmit the laser beam to be reflected by the current sampling point on the measured workpiece to form a laser echo; the receiving module 6122 is configured to receive the laser echo to acquire displacement data at the current sampling point on the workpiece to be tested.

In addition, as shown in fig. 14, the data analysis system 62 may include a fourier transform module 621, a normalization module 622, a visualization conversion module 623, and a fusion module 624, which are communicatively connected to each other, wherein the fourier transform module 621 performs fourier transform processing on the displacement data at each collected sampling point to obtain corresponding response functions; the normalization processing module 622 is configured to perform normalization processing on the response function to obtain a corresponding amplitude-frequency curve; the visual conversion module 623 is configured to perform three-dimensional visual conversion on the vibration amplitude corresponding to the extreme point on the amplitude-frequency curve to obtain a modal model corresponding to the extreme point; the fusion module 624 is configured to fuse the modal model to the digital image according to the position information of each sampling point to obtain the modal model with the digital image.

It should be noted that, in the above embodiment of the present application, as shown in fig. 14, the modal measurement system 60 may further include an excitation system 63, where the excitation system 63 is configured to obtain an excitation signal of the workpiece to be measured, so as to perform phase synchronization between the excitation signal and the vibration signal of each sampling point on the workpiece to be measured, so as to output data for modal analysis.

Illustrative electronic device

Next, an electronic apparatus according to a first embodiment of the present invention is described with reference to fig. 16. As shown in fig. 16, the electronic device 90 includes one or more processors 91 and a memory 92.

The processor 91 may be a Central Processing Unit (CPU) or other form of processing unit having data processing capabilities and/or instruction execution capabilities, and may control other components in the electronic device 90 to perform desired functions. In other words, the processor 91 comprises one or more physical devices configured to execute instructions. For example, the processor 91 may be configured to execute instructions that are part of: one or more applications, services, programs, routines, libraries, objects, components, data structures, or other logical constructs. Such instructions may be implemented to perform a task, implement a data type, transform the state of one or more components, implement a technical effect, or otherwise arrive at a desired result.

The processor 91 may include one or more processors configured to execute software instructions. Additionally or alternatively, the processor 91 may include one or more hardware or firmware logic machines configured to execute hardware or firmware instructions. The processors of the processor 91 may be single core or multicore, and the instructions executed thereon may be configured for serial, parallel, and/or distributed processing. The various components of the processor 91 may optionally be distributed over two or more separate devices, which may be remotely located and/or configured for coordinated processing. Aspects of the processor 91 may be virtualized and executed by remotely accessible networked computing devices configured in a cloud computing configuration.

The memory 92 may include one or more computer program products that may include various forms of computer-readable storage media, such as volatile memory and/or non-volatile memory. The volatile memory may include, for example, Random Access Memory (RAM), cache memory (cache), and/or the like. The non-volatile memory may include, for example, Read Only Memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer readable storage medium and executed by the processor 91 to implement some or all of the steps of the above-described exemplary methods of the present invention, and/or other desired functions.

In other words, the memory 92 comprises one or more physical devices configured to hold machine-readable instructions executable by the processor 91 to implement the methods and processes described herein. In implementing these methods and processes, the state of the memory 92 may be transformed (e.g., to hold different data). The memory 92 may include removable and/or built-in devices. The memory 92 may include optical memory (e.g., CD, DVD, HD-DVD, blu-ray disc, etc.), semiconductor memory (e.g., RAM, EPROM, EEPROM, etc.), and/or magnetic memory (e.g., hard-disk drive, floppy-disk drive, tape drive, MRAM, etc.), among others. The memory 92 may include volatile, nonvolatile, dynamic, static, read/write, read-only, random-access, sequential-access, location-addressable, file-addressable, and/or content-addressable devices.

It is understood that the memory 92 comprises one or more physical devices. However, aspects of the instructions described herein may alternatively be propagated by a communication medium (e.g., an electromagnetic signal, an optical signal, etc.) that is not held by a physical device for a limited period of time. Aspects of the processor 91 and the memory 92 may be integrated together into one or more hardware logic components. These hardware logic components may include, for example, Field Programmable Gate Arrays (FPGAs), program and application specific integrated circuits (PASIC/ASIC), program and application specific standard products (PSSP/ASSP), system on a chip (SOC), and Complex Programmable Logic Devices (CPLDs).

In one example, as shown in FIG. 16, the electronic device 90 may also include an input device 93 and an output device 94, which are interconnected by a bus system and/or other form of connection mechanism (not shown). For example, the input device 93 may be, for example, a camera module for capturing image data or video data, or the like. As another example, the input device 93 may include or interface with one or more user input devices such as a keyboard, mouse, touch screen, or game controller. In some embodiments, the input device 93 may include or interface with a selected Natural User Input (NUI) component. Such component parts may be integrated or peripheral and the transduction and/or processing of input actions may be processed on-board or off-board. Example NUI components may include a microphone for speech and/or voice recognition; infrared, color, stereo display and/or depth camera for machine vision and/or gesture recognition; a head tracker, eye tracker, accelerometer and/or gyroscope for motion detection and/or intent recognition; and an electric field sensing component for assessing brain activity and/or body movement; and/or any other suitable sensor.

The output device 94 may output various information including the classification result, etc. to the outside. The output devices 94 may include, for example, a display, speakers, a printer, and a communication network and remote output devices connected thereto, among others.

Of course, the electronic device 90 may further comprise the communication means, wherein the communication means may be configured to communicatively couple the electronic device 90 with one or more other computer devices. The communication means may comprise wired and/or wireless communication devices compatible with one or more different communication protocols. As a non-limiting example, the communication subsystem may be configured for communication via a wireless telephone network or a wired or wireless local or wide area network. In some embodiments, the communications device may allow the electronic device 90 to send and/or receive messages to and/or from other devices via a network such as the internet.

It will be appreciated that the configurations and/or approaches described herein are exemplary in nature, and that these specific embodiments or examples are not to be considered in a limiting sense, because numerous variations are possible. The specific routines or methods described herein may represent one or more of any number of processing strategies. As such, various acts illustrated and/or described may be performed in the sequence illustrated and/or described, in other sequences, in parallel, or omitted. Also, the order of the above processes may be changed.

Of course, for the sake of simplicity, only some of the components of the electronic device 90 relevant to the present invention are shown in fig. 16, and components such as buses, input/output interfaces, and the like are omitted. In addition, the electronic device 90 may include any other suitable components depending on the particular application.

According to another aspect of the present application, as shown in fig. 17 to 20B, the second embodiment of the present application further provides an electronic device 70, wherein the electronic device 70 is used for performing modal measurement on the workpiece 80 to be measured, and the electronic device 70 may include a measurement system 71 and a data analysis system 72, wherein the measurement system 71 includes a camera unit 711, an oscillation measurement unit 712, an adjustment unit 713, and a control unit 714, wherein the control unit 714 is respectively connected to the camera unit 711, the oscillation measurement unit 712, and the adjustment unit 713 in a communication manner, and is used for controlling the camera unit 711 to acquire image information of the workpiece 80 to be measured, controlling the oscillation measurement unit 712 to acquire oscillation information of the workpiece 80 to be measured by using a doppler laser oscillation measurement technique, and controlling the adjustment unit 713 to adjust a relative position between a laser beam emitted by the oscillation measurement unit 712 and the workpiece 80 to be measured, so that the laser beam emitted by the vibration measuring unit 712 scans the sampling points on the workpiece 80 point by point. The data analysis system 72 is communicatively connected to the measurement system 71, and is configured to perform data analysis processing on the acquired image information and the vibration information to output a modal model with a digital image.

It is noted that, in an example of the present application, as shown in fig. 17 and fig. 20A, the adjusting unit 713 of the measuring system 71 is implemented as a scanning unit 7131, wherein the scanning unit 7131 is used for converting the laser beam emitted by the vibration measuring unit 712 into scanning laser according to the requirement of calibration scanning by using a reflective galvanometer or a refractive prism under the control of the control unit 714 so as to perform the calibration scanning on the workpiece 80 to be measured.

Preferably, as shown in fig. 17 and 19A, the scanning unit 7131, the vibration measuring unit 712, and the camera unit 711 in the measuring system 71 are integrated into the same device (as shown in fig. 19A), and the functions of image acquisition, scan calibration, vibration measurement, etc. can be performed simultaneously through the control operation of the control unit 714 (as shown in fig. 19B). It can be understood that the measurement system 71 of the present application may take different integrated forms according to different scene requirements when in actual use.

Fig. 18 and 20B show a variant of the electronic device 70 according to the above-described embodiment of the present application, with the following differences: the adjusting unit 713 of the measuring system 71 may also be implemented as a moving unit 7132, wherein the moving unit 7132 is configured to move the workpiece 80 to be measured one by one, so that the laser beam emitted by the vibration measuring unit 712 propagates to a plurality of sampling points on the workpiece 80 one by one.

Preferably, in the above modified embodiment of the present application, as shown in fig. 18 and 20B, the measuring system 71 may further include a reflection unit 715, wherein the reflection unit 715 is disposed in a laser optical path between the vibration measuring unit 712 and the workpiece 80 to be measured, and is configured to reflect visible light from the workpiece 80 to be measured to be received by the camera unit 711 to obtain digital images corresponding to the workpiece 80 before and after being moved, so as to determine position information of each sampling point on the workpiece 80 to be measured.

According to the above-described embodiment of the present application, as shown in fig. 17, the data analysis system 72 may include a calibration scanning unit 721, a data acquisition unit 722, and an analysis modeling unit 723, which are communicably connected to each other. The calibration scanning unit 721 is configured to calibrate a position relationship between the camera unit 711 and the vibration measurement unit 712 according to a test requirement, and enable the laser beam emitted by the vibration measurement unit 712 to scan the workpiece 80 point by point according to a sampling point position preset in the digital image acquired by the camera unit 711. The data acquisition unit 722 is configured to acquire image information and position information of each sampling point acquired by the camera unit 711, and acquire vibration information of each sampling point acquired by the vibration measurement unit 712. The analysis modeling unit 723 is configured to perform data analysis processing on the acquired image information and the position information and the vibration information of each sampling point to output a modal model with a digital image.

It should be noted that the data analysis system 72 in this embodiment may be installed in a testing computer in the form of modal analysis software, wherein the computer is in communication with the control unit 714 and can operate or obtain all information of the control unit 714. It can be understood that, in the actual use process, if a higher integration requirement is required, the data analysis system may also be transplanted to an embedded system, an industrial control system, or other platforms that can implement functions such as FFT operation, modal modeling, and the like, that is, the data analysis system 72 may be integrated with the above units as required, which is not described herein again.

It should be noted that, when the tested workpiece 80 needs to be subjected to the test modal measurement, as shown in fig. 17, the electronic device 70 of the above embodiment of the present application may further include an excitation system 73 for applying the excitation vibration to the tested workpiece 80, wherein the data analysis system 72 is communicatively connected to the excitation system 73, and is configured to acquire the excitation signal from the excitation system 73, so as to synchronize the phase of the excitation signal with the vibration signal of each sampling point on the tested workpiece 80, so as to output data for modal analysis.

For example, as shown in fig. 17, the excitation system 73 may include an excitation source 731 and at least one actuator 732 communicatively connected to each other, wherein the excitation source 731 is configured to generate an excitation signal, and the at least one actuator 732 is configured to convert the excitation signal into an excitation vibration using a piezoelectric element to drive the workpiece 80 to be measured to perform a mechanical vibration.

Preferably, as shown in fig. 17, the excitation system 73 may further include an amplifier 733, wherein the amplifier 733 is communicatively connected to the excitation source 731 and the at least one actuator 732 respectively, and is configured to amplify the excitation signal from the excitation source 731 and transmit the amplified excitation signal to the at least one actuator 732 so as to meet the driving requirement of the at least one actuator 732.

It is noted that when the excitation signal of the excitation system 73 cannot be directly transmitted to the data analysis system 72, the electronic device 70 may further include an oscillation measuring system for measuring the oscillation signal of the driving surface of the at least one actuator 732, so as to indirectly obtain the excitation signal of the excitation source and synchronize the same to the data analysis system 72.

It should also be noted that in the apparatus, devices and methods of the present invention, the components or steps may be broken down and/or re-combined. These decompositions and/or recombinations are to be regarded as equivalents of the present invention.

The previous description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects without departing from the scope of the invention. Thus, the present invention is not intended to be limited to the aspects shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

It will be appreciated by persons skilled in the art that the embodiments of the invention described above and shown in the drawings are given by way of example only and are not limiting of the invention. The objects of the invention have been fully and effectively accomplished. The functional and structural principles of the present invention have been shown and described in the examples, and any variations or modifications of the embodiments of the present invention may be made without departing from the principles.

Claims

1. A modal measurement method, comprising the steps of:

scanning a plurality of sampling points on the workpiece to be detected point by adjusting the relative position between the laser beam and the workpiece to be detected;

2. The modal measurement method of claim 1, wherein the step of scanning the plurality of sampling points on the workpiece to be measured point by adjusting the relative position between the laser beam and the workpiece to be measured comprises the steps of:

3. The modal measurement method of claim 2, wherein the step of angularly adjustably deflecting the laser beam to successively change the propagation angle of the laser beam so that the deflected laser beam propagates to a plurality of sampling points on the workpiece point by point comprises the steps of:

4. The modal measurement method of claim 2, wherein the step of angularly adjustably deflecting the laser beam to successively change the propagation angle of the laser beam so that the deflected laser beam propagates to a plurality of sampling points on the workpiece point by point comprises the steps of:

refracting the laser beam through a refraction type prism so as to enable the laser beam to be transmitted to a current sampling point on the workpiece to be tested; and

5. The modal measurement method of claim 3 or 4, wherein the step of acquiring image information of the workpiece to be measured and position information of each sampling point on the workpiece to be measured comprises the steps of:

6. The modal measurement method of claim 1, wherein the step of scanning the plurality of sampling points on the workpiece point by adjusting the relative position between the laser beam and the workpiece comprises the steps of:

7. The modal measurement method of claim 6, wherein the step of acquiring the image information of the workpiece under test and the position information of each sampling point on the workpiece under test comprises the steps of:

arranging a part of transflective elements in a light path of the laser beam transmitted to the current sampling point on the workpiece to be tested;

8. The modal measurement method of any of claims 1 to 4, 6 and 7, wherein the step of acquiring vibration information at each sampling point on the workpiece under test by using a doppler laser vibration measurement technique comprises the steps of:

emitting the laser beam to be reflected by a current sampling point on the workpiece to be measured to form a laser echo; and

9. The modal measurement method of claim 8, wherein the step of performing data analysis processing on the acquired image information and the position information and the vibration information of each sampling point to output a modal model with a digital image comprises the steps of:

fourier transform processing is carried out on the displacement data at each collected sampling point to obtain a corresponding response function;

normalizing the response function to obtain a corresponding amplitude-frequency curve;

10. The modal measurement method of any of claims 1 to 4, 6, and 7, further comprising the steps of:

11. The modal measurement method of claim 10, wherein the step of acquiring the excitation signal of the workpiece to be measured to synchronize the excitation signal with the vibration signal of each sampling point on the workpiece to be measured in phase to output the bode plot of each sampling point on the workpiece to be measured comprises the steps of:

12. The modal measurement system is used for carrying out modal measurement on a workpiece to be measured, and is characterized by comprising the following components in communication connection with each other:

13. An electronic device, comprising:

at least one processor configured to execute instructions; and

14. Electronic equipment for modal measurement of a workpiece under test, wherein the electronic equipment comprises:

a measurement system, wherein the measurement system comprises:

a camera unit;

a vibration measuring unit;

an adjustment unit; and

15. The electronic device of claim 14, wherein the adjusting unit of the measuring system is a scanning unit, and the scanning unit is under the control of the control unit and is configured to convert the laser beam emitted by the vibration measuring unit into scanning laser according to the requirement of calibration scanning by using a reflective galvanometer or a refractive prism so as to perform calibration scanning on the workpiece.

16. The electronic device of claim 15, wherein the scanning unit, the vibration measurement unit, and the camera unit in the measurement system are integrated into the same device.

17. The electronic device of claim 14, wherein the adjusting unit of the measuring system is a moving unit, and the moving unit is configured to move the workpiece one by one, so that the laser beam emitted by the vibration measuring unit propagates to the sampling points on the workpiece one by one.

18. The electronic device of claim 17, wherein the measuring system further comprises a reflection unit, wherein the reflection unit is disposed in a laser optical path between the vibration measuring unit and the workpiece to be measured, and is used for reflecting visible light from the workpiece to be measured to be received by the camera unit to obtain digital images corresponding to the workpiece before and after being moved.

19. The electronic device of any one of claims 14 to 18, wherein the data analysis system comprises a calibration scanning unit, a data acquisition unit and an analysis modeling unit, which are communicably connected to each other, wherein the calibration scanning unit is configured to calibrate a positional relationship between the camera unit and the vibration measurement unit according to a test requirement, and enable the laser beam emitted by the vibration measurement unit to perform point-by-point scanning on the workpiece according to a sampling point position preset in the digital image acquired by the camera unit; the data acquisition unit is used for acquiring image information and position information of each sampling point acquired by the camera unit and acquiring vibration information of each sampling point acquired by the vibration measurement unit; the analysis modeling unit is used for carrying out data analysis processing on the acquired image information, the position information of each sampling point and the vibration information so as to output a modal model with a digital image.

20. The electronic device of any one of claims 14 to 18, further comprising an excitation system, wherein the excitation system is configured to apply an excitation vibration to the workpiece under test, and the excitation system is communicatively connected to the data analysis system, wherein the data analysis system is configured to obtain an excitation signal from the excitation system, so as to synchronize the excitation signal with the phase of the vibration signal at each sampling point on the workpiece under test, so as to output data for modal analysis.