Light source laboratory micro-vibration test system and test method thereof

Abstract

The invention relates to the technical field of optical laboratory vibration control and test, in particular to a light source laboratory micro-vibration test system, which comprises a vibration sensor array, which is composed of a plurality of high-performance MEMS sensors distributed in a tested area and is used for capturing vibration from the outside; the data acquisition module is in wireless connection with the vibration sensor array, and the data acquisition module is used for converting an acquired signal into a digital signal; the central processing unit is in wireless connection with the data acquisition module, and the central processing unit is used for analyzing and screening the digital signals transmitted by the data acquisition module; and the visual interface is in wireless connection with the central processing unit, and the visual interface is used for displaying the received digital signals to a user in a graphical mode. The device has a better effect of testing the vibration condition of the low-frequency band of 1-100 Hz.

Description

Technical Field

[0001] The present application relates to the field of optical laboratory vibration control and testing technology, and in particular to a light source laboratory micro-vibration testing system. Background Art

[0002] With the increasing demands of scientific research and technological progress, especially in precision optical laboratories, the requirements for vibration control are getting higher and higher. Currently, a large number of laboratories have adopted active or passive vibration isolation measures to reduce the impact of external factors on experiments, but how to effectively monitor the actual effect of these measures is still a major challenge.

[0003] The existing and commonly used vibration test systems mainly include traditional detection methods based on acceleration sensors and more advanced fiber optic sensing technology. The former is more popular in some primary applications due to its low cost and easy deployment, but this method is limited by measurement sensitivity and it is difficult to obtain the required signal-to-noise ratio in the low frequency band, especially in the 1-100Hz frequency range. Although the latter has higher resolution and stability and can better meet the needs of high-frequency signal acquisition, it is easily affected by electromagnetic interference in complex environments, which reduces the accuracy of the final result.

[0004] The above existing vibration test methods are unable to better test low-frequency vibration conditions and are easily affected by electromagnetic interference in complex environments, so there is room for improvement. Summary of the invention

[0005] In order to solve the problem that traditional vibration test systems cannot obtain the required signal-to-noise ratio in the low-frequency range of 1-100 Hz, the present application provides a light source laboratory micro-vibration test system.

[0006] This application provides a light source laboratory micro-vibration test system, which adopts the following technical solutions: A light source laboratory micro-vibration test system, comprising: A vibration sensor array, wherein the vibration sensor array is composed of a plurality of high-performance MEMS sensors distributed in the measured area, and the vibration sensor array is used to capture vibrations from the outside world; A data acquisition module, the data acquisition module is wirelessly connected to the vibration sensor array, and the data acquisition module converts the acquired signal into a digital signal; A central processing unit, the central processing unit is wirelessly connected to the data acquisition module, and the central processing unit is used to analyze and filter the digital signal transmitted by the data acquisition module; A visualization interface is wirelessly connected to the central processing unit, and the visualization interface displays the received digital signal to the user in a graphical manner.

[0007] By adopting the above technical solution, the vibration sensor array captures subtle vibration changes from all directions and transmits the detected signals to the data acquisition module. The data acquisition module converts the received raw signals into digital form and sends them to the central processing unit through a wireless network. The central processing unit extracts useful characteristic parameters by performing efficient calculations on a large amount of raw data, and determines whether there are abnormal conditions based on the preset threshold. Finally, the processed results are intuitively displayed through a friendly graphical user interface for reference by the staff. The setting of several high-performance MEMS sensors can capture subtle vibrations from all directions in real time, improve the detection accuracy of the test system, and facilitate the detection of vibration conditions in the low frequency band of 1-100Hz.

[0008] Optionally, the vibration sensor is an acceleration sensor or a velocity sensor.

[0009] By adopting the above technical solution, the minimum acquisition division value of the sensor is measured by the acceleration sensor, which makes it convenient for the staff to compare the size between the theoretical value and the measured value during the monitoring process of the target, thereby facilitating the measurement of whether the vibration condition of the corresponding detection point is qualified.

[0010] Optionally, the central processing unit uses Labview real-time spectrum to perform spectrum analysis and conduct on-site field debugging and analysis, or stores it as a data file and performs Matlab in-house data analysis.

[0011] By adopting the above technical solution, relevant data is recorded through real-time testing, and the data is processed through field debugging analysis and internal data analysis. The analysis and recording of data are more accurate, and dual-channel analysis facilitates comparison and reduces the possibility of data errors.

[0012] Optionally, a test method for a light source laboratory micro-vibration test system comprises: Inspection of the base plate, regular vibration attenuation testing during the construction process of the base plate; Measurement point arrangement: several test points are evenly spaced in the direction away from the laboratory, and along the direction of the outer wall of the laboratory, they are B1, B2, B3, B4, B5, B6, B7, etc.; Preliminary test: test the two test points B6 and B7; Test again, checking the two test points B5 and B6; Use Matlab to analyze the data, offset the DC component, retain most of the ring vibration characteristics, calculate RMS, and make judgments; Subsequent test plans will optimize the detection steps and conduct further tests.

[0013] By adopting the above technical solution, the construction qualification rate of the base plate is improved. Test points are set according to the distance from the laboratory, and multiple tests are performed on different test point groups. This improves the accuracy of data collection, offsets the DC component, and filters out data within the required range. The entire detection process is optimized to improve the accuracy of data detection.

[0014] Optionally, excavation is performed at the test point to the original soil, and a concrete cushion layer is poured on the original soil.

[0015] By adopting the above technical solution, a concrete cushion layer is fixed on the original soil, thereby reducing the impact of the looseness of the surface soil and the inconsistency of the original soil on the test results.

[0016] Optionally, a vibration attenuation test of the original soil on the site is conducted before the base plate is constructed, a structural vibration attenuation test is conducted after the preliminary construction of a portion of the base plate, and a structural vibration test is conducted on the base plate after the base plate construction is completed.

[0017] By adopting the above technical solution, the vibration attenuation of the original soil before the base plate construction is tested, and the base plate is tested at various stages during the construction process, thereby improving the pass rate of the base plate.

[0018] Optional, MATLAB data analysis, including, Remove non-data text, the initial sampling rate is set to a, and the non-data text in the original acceleration data is removed; Remove the DC bias and eliminate the trend. Use the detrend function and the constant parameter to remove the constant term bias. Remove short-term large-value interference, remove median filtering, use a window size of 4-6, and use high-pass filtering to remove low frequencies below 0.01Hz; Perform numerical integration on time and obtain velocity time domain through integration; Filter again to eliminate the trend, use the detrend function, use the linear parameter to remove the linear bias, the median filter window size is 4-6, and the high-pass filter is 0.01Hz; The time is integrated again to obtain the displacement time domain.

[0019] By adopting the above technical solution, the initial sampling rate is limited, non-data text is removed, DC bias is removed, short-term large-amplitude interference is removed, median filtering is removed, the window size is limited, and high-pass filtering is used to remove low frequencies below 0.01 Hz to filter out the required data; time is integrated, and the filtering operation is repeatedly removed, so that the data analysis results are more accurate.

[0020] Optionally, remove the bias of the acquired time domain data and eliminate the trend by using the detrend function and the constant parameter to remove the constant term bias; The time domain signal is converted into the frequency domain signal by using the fast Fourier transform, and the initial sampling rate is also set to a; Cut off 1-100Hz, set the bandpass filter to 2nd order, and the FFT sampling rate to a; Calculate the displacement RMS value, calculate RMS, and make a judgment.

[0021] By adopting the above technical solution, the trend is eliminated, the constant term offset is removed, and then the time domain signal is converted into a frequency domain signal, the 1-100 Hz band is intercepted, and the RMS value is calculated, so that the calculation result is more accurate.

[0022] Optional, follow-up test plan, including, Replace the data acquisition module, which is the cRio acquisition box; Multi-channel continuous acquisition, optimizing the stability of the acquisition program through multiple channels; Complete test at night: complete test at night is carried out during the soil stage; The vibration exciter equipment simulation test will be carried out after the local construction of the structural plate is completed.

[0023] By adopting the above technical solution, the accuracy of data measurement is improved.

[0024] In summary, the present application includes at least one of the following beneficial technical effects: 1. The vibration sensor array captures vibration changes from all directions. Due to the selection of high-performance MEMS sensors, the vibration sensor array can capture subtle vibration changes in the outside world and detect vibration conditions in the low-frequency band below 1-100 Hz, thereby facilitating the construction of the laboratory to meet the requirements.

[0025] 2. During the construction of the base plate, vibration attenuation tests are performed on the base plate regularly to ensure that the completed base plate meets the expected standards.

[0026] 3. Before pouring the concrete cushion layer, excavate to the original soil and pour the concrete cushion layer on the original soil to reduce the possibility of the softness of the surface soil affecting the detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a module composition diagram of the light source laboratory micro-vibration test system in Example 1 of the present application.

[0028] Figure 2 It is a flow chart of the testing method of the light source laboratory micro-vibration testing system in the second embodiment of the present application.

[0029] Figure 3 This is a flow chart of using matlab for data analysis in Example 2 of the present application.

[0030] Figure 4 This is a flow chart of using MATLAB to perform data analysis on time domain signals in Example 2 of the present application.

[0031] Figure 5 It is a flowchart of the subsequent test plan in Example 2 of the present application. DETAILED DESCRIPTION

[0032] The following is combined with Figure 1-5 This application is described in further detail.

[0033] The embodiment of the present application discloses a light source laboratory micro-vibration testing system.

[0034] Embodiment 1 Reference Figure 1 A light source laboratory micro-vibration test system includes a vibration sensor array, which includes several high-performance MEMS sensors. The several high-performance MEMS sensors are distributed at different distances from the laboratory and can capture subtle vibration changes from all directions, meeting the vibration conditions in the low-frequency range of 1-100 Hz required by this application.

[0035] Reference Figure 1 The light source laboratory micro-vibration test system also includes a data acquisition module, a central processing unit wirelessly connected to the data acquisition module, and a visual interface wirelessly connected to the central processing unit. The data acquisition module is responsible for converting the raw signals acquired by the sensor array into digital form and sending them to the central processing unit through a wireless network. The central processing unit extracts useful characteristic parameters by performing efficient calculations on a large amount of raw data, and displays the data in a more intuitive way for reference by the staff.

[0036] Reference Figure 1 The central processing unit analyzes the on-site measurement program in two directions: first, it produces a Labview real-time spectrum and then conducts on-site field debugging and analysis; second, it stores the detected data as a data file and then uses Matlab for internal data analysis. The test results are analyzed through two channels, thereby improving the accuracy of the data.

[0037] Reference Figure 1 In this application, the visualization interface uses the labview front panel for user interface development, which can realize the observation of real-time time domain signals and frequency domain signals, and display them to the staff more intuitively, so as to facilitate the staff to accurately analyze the vibration situation.

[0038] In the first embodiment of the present application, the implementation principle of a light source laboratory micro-vibration testing system is as follows: when there is vibration near the laboratory, the vibration sensor array captures subtle vibration changes from all directions and transmits the data to the data acquisition module. The data acquisition module converts the acquired raw signal into digital form and sends it to the central processing unit. The central processing unit performs efficient calculations on a large amount of raw data to extract useful characteristic parameters, and finally displays the acquired data to the staff through a visual interface.

[0039] Embodiment 2: Reference Figure 2 , a test method for a light source laboratory micro-vibration test system, first set up test points, pre-demarcate test points around the laboratory, and the test points are distributed in sequence along the direction from the outer wall of the laboratory, from far to near, they are B1, B2, B3, B4, B5, B6 and B7, first dig to the original soil at the corresponding position, and then pour a 10cm thick 1m*1m plain concrete cushion on the original soil. In this application, two vibration sensors are preferably installed on each concrete cushion. Digging the soil at the test point to the original soil reduces the hardness of the surface soil and the original soil, which is different from the interference of the test results.

[0040] Before the construction of the base plate under the laboratory, a vibration attenuation test of the original soil on site was carried out; the construction of the base plate requires the support of the supporting components. The base plate is constructed in blocks, and after the construction of one of the blocks is completed, the alternate blocks are constructed after the test is qualified, so as to reduce the possibility of affecting the adjacent blocks during the construction process, and finally a complete base plate is assembled. After the preliminary construction of part of the base plate, a structural vibration attenuation test is carried out; after the overall annular base plate is formed, a structural vibration test is carried out, thereby improving the pass rate of the base plate construction.

[0041] In the preliminary test, the two test points B6 and B7 were tested on site first. After completing the test of the two test points close to the laboratory, another test was carried out to detect the two test points B5 and B6. Multiple groups of tests were used to facilitate comparison by staff to improve the accuracy of data measurement.

[0042] Reference Figure 2 and Figure 3, using matlab for data analysis, the first step is to process the raw acceleration data tested, the initial sampling rate is a, a=256Hz, and non-data text is removed; the second step is to remove the DC bias and eliminate the trend, use the detrend function, and use the constant parameter to remove the constant term bias; the third step is to remove short-term large-amplitude interference, use median filtering (this method can effectively remove short-term spike noise while retaining most of the characteristics of environmental vibration), the window size range is 4-6, the window size in this application is 5, and the low-frequency waves below 0.01Hz are removed by high-pass wave; the fourth step is to integrate to obtain the velocity time domain, and perform numerical integration processing on the time; the fifth step is to filter again to eliminate the trend, use the detrend function, use the linear parameter to remove the linear bias, the median filter window size is 5, and the high-pass filter is 0.01Hz; the sixth step is to integrate to obtain the displacement time domain, and perform numerical integration on the time. The reason for removing the DC bias is that after the acceleration is integrated, the velocity is a straight line instead of a vibration state, which offsets the DC component. If there is a DC offset (non-zero mean) in the acceleration signal, then the integration will result in a straight line with a non-zero slope.

[0043] Reference Figure 4 , use matlab to analyze the time domain signal, remove the DC bias, use the detrend function to eliminate the trend, use the constant parameter to remove the constant term bias, convert the time domain signal into a frequency domain signal, use fast Fourier transform, set the FFT sampling rate to a=256Hz, intercept 1-100Hz, set a bandpass filter, 2nd order, select a sampling rate of 256Hz, and finally calculate the RMS value of the displacement for judgment.

[0044] Reference Figure 5 ,Subsequent test plan, replace the data acquisition module with the cRio acquisition chassis, optimize the stability of the multi-channel continuous acquisition program, connect multiple vibration sensors to several acquisition channels, perform synchronous acquisition, measure multiple groups of data, write a filtering program for the Labview real-time spectrum, conduct a complete night test in the soil stage, test the soil at night without the influence of external interference factors, and simulate the test through the vibration exciter equipment after the local construction of the structural plate is completed. Improve the test accuracy of the data by optimizing and improving the subsequent test plan.

[0045] In the embodiments of the present application, the target sensor index is selected as acceleration or velocity. If a velocity sensor is used, calculate the value of [x]*(1 / Fs), where [x] is the RMS displacement integration limit value and Fs is the sampling rate; the highest frequency limit value is [v], design the sampling rate according to [v], and the sampling rate Fs should be greater than 2.56*[v]. If the value of [x]*(1 / Fs) is greater than the minimum acquisition resolution of the sensor, it is theoretically feasible; if an acceleration sensor is used, it is necessary to calculate [x]*(1 / Fs)^2, and if the calculation result is greater than the minimum acquisition resolution of the sensor, it is theoretically feasible.

[0046] After the selection of the sensing device is completed, a collection device is selected. Taking the selection of an acceleration sensor as an example, calculate the minimum drift signal V0 = a0·S according to the minimum resolution a0 and sensitivity S of the sensor; calculate the theoretical minimum acquisition accuracy Vmin of the collection device according to the range Vtotal of the collection device and the number of bits n of the collection device, and select a collection device that can satisfy V0 < Vmin for the background noise test. Short-circuit the positive and negative poles of the collection device channel and ground the negative pole, collect the background noise signal difference δV of the collection device, and calculate the actual acquisition error δa = δV·S. If it is an acceleration sensor, δv = ∫δa·Fs dt and δx = ∫δv·Fs dt can be calculated.

[0047] In the second embodiment of the present application, the implementation principle of a test method for a micro-vibration test system in a light source laboratory is as follows: vibration tests are carried out before, during, and after the construction of the bottom plate. Vibration tests are required for the setting of test points near the laboratory. After the pouring of the test points is completed, sensors are installed on the side walls of the concrete cushion, and vibration tests are carried out according to the distance between the test points and the laboratory. The sensors transmit the data in each direction captured to the acquisition module, and the acquisition module converts the acquired original signal into a digital form and sends it to the central processing unit through a wireless network. The central processing unit extracts useful characteristic parameters by performing high-efficiency operation processing on a large amount of original data, and judges whether there is an abnormal situation according to a preset threshold. After a series of screenings, the final data display chart is intuitively displayed to the staff.

[0048] The above are all the preferred embodiments of the present application. The protection scope of the present application is not limited by this. Therefore, all equivalent changes made according to the structure, shape, and principle of the present application should be covered within the protection scope of the present application.

Claims

1. A light source laboratory micro-vibration test system, characterized in that: include, A vibration sensor array, wherein the vibration sensor array is composed of a plurality of high-performance MEMS sensors distributed in the measured area, and the vibration sensor array is used to capture vibrations from the outside world; A data acquisition module, the data acquisition module is wirelessly connected to the vibration sensor array, and the data acquisition module converts the acquired signal into a digital signal; A central processing unit, the central processing unit is wirelessly connected to the data acquisition module, and the central processing unit is used to analyze and filter the digital signal transmitted by the data acquisition module; A visualization interface is wirelessly connected to the central processing unit, and the visualization interface displays the received digital signal to the user in a graphical manner.

2. A light source laboratory micro-vibration test system according to claim 1, characterized in that: The vibration sensor is an acceleration sensor or a velocity sensor.

3. A light source laboratory micro-vibration test system according to claim 3, characterized in that: The central processing unit uses Labview real-time spectrum to perform spectrum analysis and conduct on-site field debugging and analysis, or stores it as a data file and performs Matlab indoor data analysis.

4. A method for testing a light source laboratory micro-vibration test system, using the light source laboratory micro-vibration test system according to any one of claims 1 to 3, characterized in that: include, Inspection of the base plate under the laboratory, and regular vibration attenuation testing during the construction process of the base plate; Measurement point arrangement: several test points are evenly spaced in the direction away from the laboratory, and along the direction of the outer wall of the laboratory, they are B1, B2, B3, B4, B5, B6, B7, etc.; Preliminary test: test the two test points B6 and B7; Test again, checking the two test points B5 and B6; Use Matlab to analyze the data, offset the DC component, retain most of the ring vibration characteristics, calculate RMS, and make judgments; Subsequent test plans will optimize the detection steps and conduct further tests.

5. A light source laboratory micro-vibration test system according to claim 4, characterized in that: Excavate the test point to the original soil, and pour a concrete cushion layer on the original soil.

6. A light source laboratory micro-vibration test system according to claim 5, characterized in that: Before the construction of the base plate, a vibration attenuation test of the original soil on site is carried out. After the preliminary construction of part of the base plate, a structural vibration attenuation test is carried out. After the construction of the base plate is completed, a structural vibration test is carried out on the base plate.

7. A light source laboratory micro-vibration test system according to claim 4, characterized in that: Matlab data analysis includes: Remove non-data text, the initial sampling rate is set to a, and the non-data text in the original acceleration data is removed; Remove the DC bias and eliminate the trend. Use the detrend function and the constant parameter to remove the constant term bias. Remove short-term large-value interference, remove median filtering, use a window size of 4-6, and use high-pass filtering to remove low frequencies below 0.01Hz; Perform numerical integration on time and obtain velocity time domain through integration; Filter again to eliminate the trend, use the detrend function, use the linear parameter to remove the linear bias, the median filter window size is 4-6, and the high-pass filter is 0.01Hz; The time is integrated again to obtain the displacement time domain.

8. A light source laboratory micro-vibration test system according to claim 7, characterized in that: It also includes removing the bias of the acquired time domain data, eliminating the trend, using the detrend function, and using the constant parameter to remove the constant term bias; The time domain signal is converted into the frequency domain signal by using the fast Fourier transform, and the initial sampling rate is also set to a; Cut off 1-100Hz, set the bandpass filter to 2nd order, and the FFT sampling rate to a; Calculate the displacement RMS value, calculate RMS, and make a judgment.

9. A light source laboratory micro-vibration test system according to claim 4, characterized in that: Subsequent testing plans include: Replace the data acquisition module, which is the cRio acquisition box; Multi-channel continuous acquisition, optimizing the stability of the acquisition program through multiple channels; Complete test at night: complete test at night is carried out in the soil stage; The vibration exciter equipment simulation test will be carried out after the local construction of the structural plate is completed.

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