CN101832813A - Noise and Vibration Measurement System Based on Virtual Instrument Technology - Google Patents

Abstract

The noise and vibration measurement system based on virtual instrument technology has analog signal input and analog signal output. Can output and input at the same time, also can output and input separately. There are two ways of analog signal input: IEPE sensor input and voltage signal input, and the output mode is analog voltage signal output. Both input and output are connected to the data acquisition module through the BNC line, and then the data acquisition module is connected to the computer through the USB line to input the sensor signal into the computer; the computer software processing module integrates the following analysis and measurement modules: spectrum analysis module, octave Analysis module, transfer function measurement module and viewing recorded signal module.

Description

Noise and Vibration Measurement System Based on Virtual Instrument Technology

1. Technical field

The invention relates to a noise and vibration measurement system, in particular to a noise and vibration measurement system based on virtual instrument technology which can be used to generate, measure and analyze noise and vibration signals.

2. Background technology

Noise and vibration measurement is an important basis for scientific research in noise control, evaluation of noise pollution and selection of control measures. Noise and vibration measurement system is an important part of noise and vibration measurement, widely used in noise and vibration experimental research and noise monitoring and other occasions.

Existing test methods generally include time-domain signal observation and frequency-domain analysis. Time-domain signal observation refers to displaying the waveform of the noise and visually observing the change of the signal. Frequency domain analysis generally includes Fourier analysis and octave analysis of the signal. Fourier analysis obtains its spectrum information, that is, the amplitude and phase value of the signal at a certain frequency point. Octave or one-third octave analysis can obtain its amplitude in each frequency range and the total value of the whole frequency band, and weight the signal according to the need to obtain the corresponding weighted value.

Noise and vibration measurement systems currently on the market are expensive, bulky, and inconvenient to carry. The invention provides a realization method of a noise and vibration measurement system based on virtual instrument technology, which uses computer software for data processing, has full functions, low cost, small volume, light weight and good stability. The invention can simultaneously generate excitation signals and real-time monitoring of noise and vibration, and perform time domain analysis, frequency spectrum analysis, octave analysis and transfer function measurement on signals.

3. Contents of the invention

The purpose of the present invention is to provide a new noise and vibration measurement system for the shortcomings of the current acoustic testing system, such as lack of centralized functions, large volume, heavy weight, and high price. While powerful, it has the advantages of small size, light weight, low cost, and good stability.

To achieve the purpose of the invention, the invention provides a noise and vibration measurement system based on virtual instrument technology.

The inventive method is: two kinds of signal input modes are arranged: i.e. IEPE sensor input and electric signal input, respectively corresponding to be used for real-time analysis sound signal and electric signal; When adopting IEPE signal input mode, at first IEPE sensor (microphone or acceleration Meter) and the IEPE sensor input end of the data acquisition module constitute a continuous data acquisition module, the two are connected by a BNC line, and then the continuous data acquisition module is connected to the computer through a USB line to input the sensor signal into the computer; when using electrical signal input, First, the electrical signal terminal and the electrical signal input terminal of the data acquisition module form a continuous data acquisition module, and the two are connected through a BNC line, and then the continuous data acquisition module is connected to a computer through a USB line to input sensor signals into the computer. One output mode: analog voltage signal output, connect the analog voltage output terminal of the data acquisition module to the corresponding output device with a BNC line.

The analysis process is:

Firstly, set the parameters of the system, including input parameter setting, output parameter setting and signal recording setting. The input parameter setting mainly includes the selection of the input signal type. The signal type is selected as "electrical signal input" or "IEPE sensor input". When selecting the IEPE sensor, it is necessary to set the corresponding sensor sensitivity, input range selection, analysis bandwidth and spectrum line number selection; The input parameter setting mainly includes whether to output signal, the selection of output signal type, including the selection of pure tone signal, white noise, pink noise and custom signal, and the setting of corresponding parameters; the signal recording setting whether to perform signal recording, the position and recording time of signal recording . System settings can be exported to a configuration file which can be imported for the next measurement.

After the setting is complete, select whether the sensor needs to be calibrated before measuring. The method of calibrating the sensor is: connect the sensor to the corresponding calibrator, select the sensor calibration module, and click to start the calibration in the pop-up dialog box. The calibrated sensor Sensitivity will be displayed on the interface.

During measurement, you can choose signal generator, spectrum analysis module, octave analysis module, transfer function measurement module and view record signal module. The signal generator module is used to generate various noise signals separately; the spectrum analysis module performs spectrum analysis on the noise to obtain the spectrum information of the signal; the octave analysis module performs octave analysis on the noise; the transfer function measurement module can obtain two input signals The transfer function and impulse response; the view record signal module is used to view the recorded signal during measurement, and can be exported as a wav file.

Noise and vibration measurement system based on virtual instrument technology, including data acquisition module with analog input function and analog output function. Write software to control output signal generation and real-time analysis of input signals. The data acquisition module has four BNC input interfaces, corresponding to two IEPE sensor input interfaces, two electrical signal input interfaces, and one BNC output interface, and is connected to the computer through a USB data line. It has the advantages of fast transmission rate, small interference signal, small size and light weight.

The characteristics of the present invention are: providing a noise and vibration measurement system based on virtual instrument technology, the acquisition system of the present invention has excellent working reliability, integrates many analysis functions, virtualizes the instrument, reduces the cost, and has a large volume Small, light in weight, powerful in function and large in expansion space, good in stability.

4. Description of drawings

Figure 1 The whole test flow chart

Figure 2 Schematic diagram of the hardware panel of the noise and vibration measurement system

Figure 3 The main interface of the noise and vibration measurement system software

Figure 4 Noise and vibration measurement system software system configuration interface

Figure 5 Microphone Calibration Interface of Noise and Vibration Measurement System Software

Figure 6 Noise and vibration measurement system software signal generator interface

Figure 7 Noise and vibration measurement system software Fourier analysis interface

Figure 8 Noise and vibration measurement system software octave analysis interface

Figure 9 Noise and vibration measurement system software transfer function measurement interface

Figure 10 Noise and vibration measurement system software view record signal interface

5. Specific implementation

The hardware part of the present invention also includes a computer connected to the data acquisition module through a USB interface. The data acquisition module does not analyze the signal, and all analysis processes are processed by the software in the computer.

The method comprises the following steps: (1) selecting a suitable input mode, connecting the input signal with the input end of the data acquisition module, connecting the corresponding output device with the output end of the data acquisition module, and then connecting the data acquisition module with the computer , to ensure that the hardware works normally; (2) run the test software, and configure the system parameters before the test, including input settings, output settings, and signal record settings; (3) select the corresponding analysis module to start the test, and at the same time save the analysis results (4) end, exit the program or start a new task.

As shown in Figure 1, the testing process is divided into two parts.

The first part is hardware connection, corresponding to step 10. When using the IEPE sensor input mode, connect the IEPE sensor (microphone or accelerometer) and the data acquisition module through the BNC line, and when using the electrical signal input mode, connect the electrical signal to the electrical signal input terminal of the data acquisition module through the BNC line; Connect the output device with the output terminal of the data acquisition module with a BNC cable, then connect the data acquisition module with the computer through a USB cable, and finally perform a hardware self-test to ensure that the hardware works normally.

The second part is the software processing part. The software processing module of the present invention integrates the following analysis and measurement modules: a spectrum analysis module, an octave frequency analysis module, a transfer function measurement module and a viewing and recording signal module.

Step 11 is the initial action, open the software program, the main interface of the software is shown in Figure 3.

Step 12 starts a new task.

Step 13 sets the system parameters for this task, the configuration interface is shown in Figure 4, including input settings, output settings and signal recording settings. The input parameter setting mainly includes the selection of the input signal type. The signal type is selected as "electrical signal input" or "IEPE sensor input". When selecting the IEPE sensor, it is necessary to set the corresponding sensor sensitivity, input range selection, analysis bandwidth and spectrum line number selection; The input parameter setting mainly includes whether to output signal, the selection of output signal type, including the selection of pure tone signal, white noise, pink noise and custom signal, and the setting of corresponding parameters; the signal recording setting whether to perform signal recording, the position and recording time of signal recording . System settings can be exported to a configuration file which can be imported for the next measurement.

Step 14 is sensor calibration, see Figure 5. After all system parameters are set, choose whether to calibrate the sensor. Normally, the sensor needs to be calibrated before each use of the system.

Step 15 selects the analysis module. The analysis module of this application includes the signal generator in FIG. 6, the Fourier analysis module in FIG. 7, the octave analysis module in FIG. 8, the transfer function measurement module in FIG. 9 and the viewing and recording signal module in FIG. Select the corresponding module and set the analysis parameters.

Step 16 starts to measure a certain analysis module.

Step 17 ends the measurement of an analysis module, and at the same time, the analyzed data and pictures can be saved. During the analysis, the task can also be paused.

After step 18 ends the current measurement task, choose to start a new test task and repeat step 12. Otherwise the program can be ended by step 19. Complete all test tasks.

Claims (9)

1. A noise and vibration measurement system based on virtual instrument technology is characterized in that an analog signal input and an analog signal output are provided. There are two ways of analog signal input: IEPE sensor input and voltage signal input. The output mode is analog voltage signal output. Both input and output are connected to the data acquisition module through the BNC line, and then the data acquisition module is connected to the computer through the USB line. The sensor signal is input into the computer; the computer software processing module integrates the following analysis and measurement modules: time domain analysis module, frequency spectrum analysis module, octave frequency analysis module, transfer function measurement module and viewing record signal module. 2. The noise and vibration measurement system based on virtual instrument technology according to claim 1, wherein the method for calibrating the sensor during analysis is: by standard sensing parameter comparison mode, the calibration method is selected after starting a new task. In the sensor calibration module, select whether to calibrate the sensor in the pop-up dialog box. 3. The noise and vibration measurement system based on virtual instrument technology according to claim 1, characterized in that it can continuously output excitation signals and continuous monitoring and analysis input signals at the same time during analysis, and can also output separately as a signal generator or separately The input measures and analyzes the signal. 4. The noise and vibration measurement system based on virtual instrument technology according to claim 1 is characterized in that the IEPE sensor and data acquisition module comprising microphone or accelerometer constitute a continuous data acquisition module, which is connected by a BNC line, and then Connect the continuous data acquisition module to the computer through the USB cable to input the sensor signal into the computer. 5. The noise and vibration measurement system based on virtual instrument technology according to claim 1, characterized in that it includes an analog signal output, and the output terminal is connected with a corresponding output device for providing a loudspeaker or a vibration exciter motivating signal. 6. The noise and vibration measurement system based on virtual instrument technology according to claim 1, characterized in that the input signal is analyzed by FFT, the windowing type, average mode and average time can be set, and the data and images can be saved after the measurement . 7. The noise and vibration measurement system based on virtual instrument technology according to claim 1 is characterized in that an octave analysis is carried out to the input signal, and octave or 1/3 octave analysis can be set, and the average mode and Average time, data and images can be saved at the end of the measurement. 8. The noise and vibration measurement system based on virtual instrument technology according to claim 1, characterized in that the transfer function between two signals can be measured, and the average mode and average time can be set during analysis. 9. The noise and vibration measurement system based on virtual instrument technology according to claim 1, characterized in that the measurement signal can be recorded simultaneously during the measurement, and the recorded signal can also be checked and exported as wav by checking the recorded signal module after the measurement is over. document.

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