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SV SLA-PA201 Manual

Smart sound/vibration analyzer
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Smart Sound/Vibration Analyzer
(Real-Time Based Measurement System)
Manual
First Edition(Ver. 1.7)
SV Corp.

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  • Page 1 Smart Sound/Vibration Analyzer (Real-Time Based Measurement System) Manual First Edition(Ver. 1.7) SV Corp.
  • Page 2 This document is on revising. We will upload the revised document to FTP Server(Refer next page) at every revising. Of course, you can download a upgraded program(Smart Sound/Vibration Analyzer.) Copyright © by SV Corporation. http://www.svdigital.com, http://www.svemall.com ftp://realwave:realwave@svdigital.com email : sales@svdigital.com...

  • Page 3: Table Of Contents

    Contents I. Composition of Smart Sound/Vibration Analyzer ................5 II. Installation & Operation Procedure ....................6 1. S/W Installation ..........................6 2. H/W Installation ............ 오류! 책갈피가 정의되어 있지 않습니다. 3. Run and Registration ........................7 4. Firmware Upgrade ........................8 III.
  • Page 4 3. Measuring with RPM Meter ...................... 53 VII. The way to use RealWave Desk for PC ..................55 1. Create a Project / Open ....................55 2. Adding a file / Delete ......................56 3. Control of Graph ........................57 4.

  • Page 5: Composition Of Smart Sound/Vibration Analyzer

    I. Composition of Smart Sound/Vibration Analyzer - AC Adapter: 1set - USB Interface Cable: 1 ea - Smart Sound/Vibration Analyzer: 1 ea - S/W CD(RealWave S/W, Firmware Update S/W, RealWave Desk S/W) : 1ea - Manual: 1 ea - Portable Aluminum Hardcase : 1 ea [Fig.

  • Page 6: Installation & Operation Procedure

    II. Installation & Operation Procedure 1. S/W Installation Before installing of the RealWave program on PDA, you must install ActiveSync on your PC. Please refer to the chapter VIII to install ActiveSync. After installation of ActiveSync, connect PC with PDA via USB cable and Insert the CD. Run the RealWave.exe file from the RealWave folder of the CD-Rom drive.

  • Page 7: Run And Registration

    To run Launch RealWave program, click the tap [Start >> Programs], and then click ‘RealWave” icon on the window of [Fig. II-1-5]. 2. Run and Registration 2. 1 Unregistered PDA If running RealWave program at unregistered PDA, please enter given license number on the register window when appears a window like [Fig.

  • Page 8: Firmware Upgrade

    3. Firmware Upgrade 3. 1 Check firmware version If you select [About RealWave] menu in [File], dialog window appears in [Fig. II-3-2]. You can check the information of hardware including firmware version. [Fig. II-3-1] Select [About RealWave…] [Fig. II-3-2] Check firmware version menu 3.
  • Page 9 When running ‘FirmUp1.0_ENG.exe’ file on PDA, the program runs like [Fig. II-3-5]. Press [Open] button on the window of [Fig. II-3-6]. Select folder and file (*.bin) to update and press [Open] button on the window of [Fig. II-3-7]. [Fig. II-3-5] FirmUp window [Fig.

  • Page 10: Basic Functions Of Program

    III. Basic Functions of Program 1. Icons 1. 1 Vibration Level Meter Icon for vibration level meter mode [Fig. III-1-1]. icons are activated. Icon to set measurement option of vibration level meter mode[Fig. III-1-2] Icon to control the result display[Fig. III-1-3] Icon to hear sounds in real-time Icon to display data only (without saving) in real-time and be called ‘ARM button’...
  • Page 11 [Fig. III-1-4] Setting the Sound [Fig. III-1-5] Sound Level [Fig. III-1-6] Sound Options Level Meter Mode Meter 1. 3 FFT Analyzer Icon for FFT Analyzer. If pressing the icon, graph control icon , option setting icon sound hearing mode icon are activated.

  • Page 12: Control Of Wave File

    [Fig. III-1-10] RPM Meter 1. 7 Entering record information Icon to enter record information. Record information window appears like [Fig. III-1-13]. click [Fig. III-1-11] Record information window 1. 8 Measurement and Playback : ARM mode – Icon to display data only in real-time without data store. : Record mode –...
  • Page 13 [Fig. III-2-1] Open a wave file [Fig. III-2-2] Opening window of wave file 2. 2 Save As… After opening a file, file name can be checked by clicking icon to convert window like [Fig. III-2-3]. Upon clicking [File>>Save As…] tap, one of the window from[Fig. III-2-4] to [Fig. III-2-6] will appear, so you can define a folder and file name at the window.

  • Page 14: Open & Save Configuration

    2. 3 Deleting currently opened file [File>>Delete] is showed [Fig. III-2-8] and you can erase .wav file which are selected currently or erase all files which include export files. It will not be activated if there’s no opened file. (When selecting [File>>Delete] tap, currently opened files are deleted.) [Fig.
  • Page 15 [Fig. III-4-1] Vibration value display [Fig. III-4-2] Vibration value and Trace display To export data, click [File>>Export] tap, and then the window [Fig. III-4-3] is opened. Check the data or image file which wants to export, select file type and click ‘Export’ button. At last, just close window by clicking [Ok] button.

  • Page 16: Transducer Type And Calibration

    [Fig. III-4-5] Exported octave data file (TEXT) [Fig. III-4-6] Automatic Export After measurement 4. 2 Sound Level Meter, FFT, Spectrogram, Octave Mode Sound Level Meter, FFT and Octave analysis mode support both data and graph image export. But spectrogram mode supports graph image export only. In the exported data, the frequency and corresponding values are arranged vertically.
  • Page 17 adjust gain if the signal is low. To use AutoRange function is more desirable than hand-operated adjustment. [AutoRange] calculates input signal and automatically adjusts gain. So it would be better to accomplish AutoRange before calibration. [Fig. III-5-3] shows AutoRange process. HighTech RealWave H/W has an analog gain with 10 times, but digital gain is used at gain adjustment.

  • Page 18: Recording Options

    [Fig. III-5-4] AutoRange [Fig. III-5-5] Calibration [Fig. III-5-6] Completion of window calibration 6. Recording Options When selecting [File>>Recording Options…] tap, a recording option window will appear like [Fig. III-6-1]. [Save Wave File In VLM / SLM] option is for if saving wave file in vibration level meter / sound level meter mode or not.

  • Page 19: Recording Information

    - [File Name] option is to define file name. Once measurement is accomplished, each recording session automatically generates numeric name after the given file name. For example, let us consider a series of measurements with the name “SV”, numeric name automatically generated as “SV001.wav”, “SV002.wav”, etc.
  • Page 20 [Fig. III-7-1] Recording Info. [Fig. III-7-2] Completion to [Fig. III-7-3] Example of pre- enter Rec. Info. defined location Do not use special character \ / : * ? “ < > for [Location]...

  • Page 21: Real Time Measurement In Vibration Level Meter/Sound Level Meter

    IV. Real Time Measurement in Vibration Level Meter/Sound Level Meter 1. Basic Theory of Vibration Level Meter / Sound Level Meter 1. 1 Understanding of Integration Time and Time Constant The RMS(Root-Mean-Square) calculation routine is based on “IEC60804:2000-Integrated Averaging Sound Level Meter” and “ISO8041:1990-Human response to vibration-Measuring instrumentation”.
  • Page 22 Generally, the time constant is set with 0.035sec(Impulse), 0.125sec(Fast), 1sec(Slow). Each term of times writes in the parenthesis. If you want to measure the impulse signal, you have to use 0.035 sec time constant. If you use more time constant (more than 10sec), the RMS has crushed values and the response time is also slow.
  • Page 23 For getting the peak-to-peak(P2P) value, our system also use detector. At first, the positive and negative peak values are calculated, and then we can get P2P from the difference of positive P2P and negative P2P. The positive peak values are calculated from the positive signal and the negative peak values are calculated from the negative signal.
  • Page 24 is Sampling Frequency. RealWave uses the “Forward Euler” method, which is where simplified from Trapezoidal Method. We can write it as below : − <Eq. IV-1-7> − − The frequency response function of integrator is shown in the [Fig. IV-1-6]. [Fig.
  • Page 25 gradually in the high frequency region. But the integrated values(velocity or displacement) have a very small values less than -50dB. Finally, the errors rarely affect the integrated value. The integrated values have linearity in the low frequency which is in range of 23% of sampling frequency.

  • Page 26: Setting Of Measuring Option

    2. Setting of measuring option 2. 1 Selection of Filter 2. 1. 1 Filter selection of vibration level meter A window is opened to press button like [Fig. IV-2-1]. You can see 9 type filters. Here are the list below : - 1Hz Highpass Filter - 5Hz Highpass Filter - 10Hz Highpass Filter...
  • Page 27 If you select WBCombined filter, Quantity value become initialize to RMS value. 2. 1. 2 Filter selection of sound level meter A window is opened to press button like [Fig. IV-2-2]. You can see 2 type filters. - 1Hz Highpass Filter - 20Hz Highpass Filter [Fig.
  • Page 28 [Fig. IV-2-4] SLM Integration Time Setting [Fig. IV-2-6] Measured Results 2. 3 Detector The results of 3 detectors are displayed in vibration level meter and 2 detectors are displayed in sound level meter simultaneously. Only the data of the selected detector are displayed and stored. For example, if you want to measure acceleration in vibration level meter, you can select only a detector like [Fig.
  • Page 29 [Fig. IV-2-9] One Detector Selection in SLM [Fig. IV-2-10] Activated Window for One Detector in SLM You can measure acceleration, velocity, displacement with various physical quantities at the same time in the vibration level meter. The various quantities are RMS(Root-Mean-Square), Peak, Peak To Peak, Max and Min.
  • Page 30 [Fig. IV-2-13] Setting the reference of decibel in VLM <Table IV-2-1> The Reference of Decibel Korea, etc. − − Acceleration − − Velocity − − Displacement 10 m You can measure the Leq, Lp, Lmax, Lmin, Lpk in sound level meter. [Fig.
  • Page 31 [Fig. IV-2-16] Setting the reference of decibel in SLM 2. 4 Display You can choose one detector among 3 detectors in Vibration Level Meter mode and among 2 detectors in Sound Level Meter mode in the [Detector] of [Display] Option. You can see 4 types- [None], [Trace], [Octave], [FFT]-graph as display option from [Fig.

  • Page 32: Display Option

    [Fig. IV-2-21] Display-FFT in VLM [Fig. IV-2-22] Display-Octave in VLM But octave and FFT graph is shown only in the WBCombined Filter. The 1/1, 1/3 and 1/6 Octave analysis which is selected in FFT option window is supported. So after you changed to FFT mode, you have to press the FFT option button to set octave.

  • Page 33: Measurement And Storage

    3. 2 Octave graph Control of octave graph is similar to controlling trace graph. For more detailed information about the control, see the pictures from [Fig. IV-3-4] to [Fig. IV-3-6]. [Fig. IV-3-4] Adjustment of the [Fig. IV-3-5] Entering the range [Fig.

  • Page 34: Playback And Analysis

    [Fig. IV-4-3] File with Vibration Level [Fig. IV-4-4] File with Vibration Level and Octave Results If you want to get results with vibration level and octave data together as [Fig. IV-4-4], you should set the octave graph at [Display] in vibration level meter. 5.

  • Page 35: Input Of Measurement Information

    [Fig. IV-5-1] Playback Button is Activated after Loading Wave File Measured and Analyzed Data File is overwritten at every playback. If you want to analyze with another option and playback, you have to change the results file name absolutely. 6. Input of Measurement Information Press toolbar switch button in red circle of [Fig.

  • Page 36: Setting Options For Human Vibration Measurement

    - Buffer Size : 2048 - Hanning Window - Exponential Averaging : Time constant is same to that of detector. - Frequency Range : 1~100Hz - Nth Octave : 1/1, 1/3, 1/6 Octave is useful. This parameter is changeable in [Nth Octave] of FFT Analysis(or Spectrogram, Octave Analysis) Option.
  • Page 37 [Fig. IV-8-3] Recording Option [Fig. IV-8-4] Entering Recording information 8.3. Entering Recording information 1 Select [File>>Recording Information…] 2 Enter name, object, location and direction of measurement in advance. 8.4. Selecting Vibration Level Meter and Setting the measurement options 1 Change the analysis mode to vibration level meter. 2 Select the vibration options as [Fig.
  • Page 38 8.5. Measurement 1 Confirm the status of measurement to press [ARM] button. 2 Start measurement to press [Record] button. 3 Enter recording information to press [Entering recording information] button. [Fig. IV-8-7] ARM Button [Fig. IV-8-8] Recording Button [Fig. IV-8-9] Entering recording information Button...

  • Page 39: Real Time Fft Spectrum Spectrogram And Octave Analysis

    V. Real Time FFT Spectrum Spectrogram and Octave Analysis 1. Understanding of Frequency Analysis The shape of the time signal is so complex that we can’t see the information of frequency in the measured time signal. Therefore, we have to calculate FFT (Fast Fourier Transform) analysis to get the information of frequency-the periodicity of time signal.
  • Page 40 <Table V-2-1> Defined Parameters for FFT Parameters Definition Equation Sampling Frequency User Definition Useful Frequency Range span span 2.56 Buffer Size User Definition 1 or Display Line 2.56 2.56 f Δ Δ = Frequency Resolution Δ = t Δ Sampling Interval(sec) Recording Time ⋅...
  • Page 41 Freq Freq [Fig. V-2-2] Ideal FFT [Fig. V-2-3] Actual FFT 2. 1 Windowing We must use windowing function to solve leakage error. The procedure shown in [Fig. V-2-4] is the windowed time signal which is original time multiplied by windowing function. The figure (b) is shown the finite periodicity of time signal that is recognized in FFT algorithms, but figure (d) represents the infinite periodicity of time signal by multiplying original time signal and windowing function.
  • Page 42 where is buffer size. There are all kinds of window function, but generally hanning, flat-top and rectangular(no window) window is used. Time domain Frequency domain -100 -120 -0.2 -140 Normalized Frequency ( ×π rad/sample) Samples [Fig. V-2-5] Various Windowing Functions However windowing causes the leakage of time signal’s energy as [Fig.
  • Page 43 2. 3 Averaging of FFT Spectrum The reason of averaging spectrum is to remove noises in the spectrum. There are linear averaging, exponential averaging and peak hold averaging. 2. 3. 1 Linear Averaging Let’s suppose that is FFT spectrum of the first time signal buffer, is FFT spectrum of the second time signal buffer and so on as [Fig.
  • Page 44 … Time1 Time2 Time3 − t τ τ time [Fig. V-2-10] Exponential Averaging 2. 3. 3 Peak Hold Averaging This averaging keeps the biggest peak value of spectrum at the same frequency to repeat with averaging number. This theory is shown in [Fig. V-2-10] and <Eq. V-2-5>. ≤...

  • Page 45: Fft Based Octave Analysis

    Display Line This real peak is not shown in graph This points are displayed in the graph Real Spectrum Freq f Δ [Fig. V-2-11] Picket Fence Error 3. FFT Based Octave Analysis FFT analysis is named narrow band frequency analysis, but octave analysis which is describing in this paragraph is called broad band analysis.

  • Page 46: Weighting

    [Fig. V-3-3] 1/1 and 1/3 Octave Bandpass Filters 1/1 and 1/3 octave bandpass filters are shown in [Fig. V-3-3]. As previously mentioned, we can calculate the octave data from FFT spectrum. The relationship is shown in [Fig. V-3-4]. [Fig. V-3-4] Relationship between FFT Spectrum and Octave Analysis Equation for calculating is <Eq.
  • Page 47 as frequency at specific sound pressure level(SPL). Sometimes, Phon unit is used instead of SPL. Phon is same to the SPL at 1kHz. For example, the curve passing on 80dB at 1kHz is called ‘80phon curve’. The definition of weighting functions is listed in <Table V-4-1>. <Table V-4-1>...

  • Page 48: Integration In Frequency Domain

    [Fig. V-4-2] A, B, C-Weighting Frequency Response [Fig. V-4-3] D, E-Weighting Frequency Response 5. Integration in Frequency Domain Velocity and displacement spectrum can be analyzed in FFT and Octave, Spectrogram analysis when accelerator is used. For this, you select [Integral] option in [Fig. V-5-1]. The detailed theory of integral in frequency domain sees [VI.

  • Page 49: Setting The Options Of Measurement

    [Fig. V-5-1] Integration in Frequency Domain 6. Setting the Options of Measurement Setting the options of measurement of frequency analysis, spectrogram and octave analysis is defined in the same option’s window. If you press ‘FFT & Octave option’ button , the window of [Fig.

  • Page 50: Setting The Option Of Display

    Selecting the exponential averaging have been activated the combo box of time constant. You can choose the proper time constant and this function doesn’t offer the automatic stopping with [ Stop]. Frequency weighting is used to analyze the noise with A, B, C, D, W weighting filter. A-weighting is an ordinary weighting in noise analysis.

  • Page 51: Record And Playback

    [Auto Scale] and [Peak Auto-Detecting] function is not offered and only the adjustment of frequency is available in the spectrogram graph. In octave analysis, [Auto Scale] function is offered but [Peak Auto-Detecting] function is not offered. However, the bandwidth being pressed for 1 second is changed from green to white bar, and then you can read frequency and magnitude in the leftmost top of octave graph.

  • Page 52: Fft Based Rpm Meter

    VI. FFT Based RPM Meter 1. Understanding about the RPM Measurement The RPM is usually measured using a tachometer. Tachometer counts the revolution of a rotator using optical sensor and reflector or using the photo coupler and the hole of rotator or magnetic sensor and the teeth of rotator.

  • Page 53: Measuring With Rpm Meter

    <Table VI-2-1> Relationship of Maximum RPM, Sampling Frequency and Buffer Size Max. RPM Sampling Frequency(Hz) Buffer Size 12000 1024 24000 1024 2048 48000 2048 4096 96000 4096 4096 As mentioned in V-2-4 paragraph, a frequency analysis generates a picket fence error. We can’t get an exact frequency which corresponds to rotational RPM.
  • Page 54 3. 1 Using the Velocity Graph or Displacement Graph to get a fit RPM It is difficult that you find the fundamental frequency in the harmonic frequency of spectrum of acceleration. The spectrum of rotational vibration with the fluctuation from 1610PRM to 1660RPM is shown from [Fig.

  • Page 55: The Way To Use Realwave Desk For Pc

    VII. The way to use RealWave Desk for PC 1. Create a Project / Open When user creates a new project of file menu, project information dialog is opened. Choose the route of the project which has to be installed, enter the project name and just put the OK button [Fig. VII-1-1].

  • Page 56: Adding A File / Delete

    [Fig. VII-1-3] Project loading Adding a file / Delete Click a file additional icon on the toolbar or after choose data folder of the tree control, then click the mouse on the right button when user add a wave file of file menu and choose the wave file which has to be added at the Project, the wave file and the result file of analysis are added like [Fig.

  • Page 57: Control Of Graph

    Control of Graph When double clicking the folder that a data from tree control, a graph is appeared on the right of the window like [Fig. VII-3-1]. [Fig. VII-3-1] VLM / FFT Control of Graph • VLM Trace : The Trace graph will be displayed on the button side in VLM. User can see the cursor value by clicking of mouse left button.

  • Page 58: Control Of Sound

    [Fig. VII-4-1] The control of property list Control of Sound If user roading the data from project tree, sound control menu of toolbar is activated like [Fig. VII- 5-1]. Sound play, stop, play time are displayed. [Fig. VII-5-1] Control of Sound List of Result Report The measuring result data is displayed as a report form of ISO6954 like [Fig.
  • Page 59 • Open : Tap to load a stored result list file. • Save As : Tap to save a current result list file as another name. • Delete : Tap to delete a date of selected list. • Excel : Tap to change details of list as MS Office Excel file like [Fig. VII-6-2]. [Fig.

  • Page 60: Installation Of Activesync And Communication With Pda

    VIII. Installation of ActiveSync and Communication with PDA 1. What is Microsoft ActiveSync? Microsoft ActiveSync is a program which synchronizes with PC and PDA. If PDA is connected with PC, many data is transported each other. If selecting the folder named Mobile Device, user can see the internal data of PDA.
  • Page 61 [Fig. VIII-2-2] Up to here, installation of the program is completed. First, PC and PDA has to be connected each other using USB cable or cradle because connection of PDA will be carried out from now on. [Fig. VIII-2-3] Press the NEXT button after connection as [Fig. VIII-2-3]. In the following, relationship of partner has to be established to use PDA at the office.
  • Page 62 [Fig. VIII-2-4] [Fig. VIII-2-5] [Fig. VIII-2-6] All check boxes should be unchecked like [Fig. VIII-2-6] and push the NEXT button because this step is for what the data of PC and PDA is transferred each other. And then, the connection comes to an end.
  • Page 63 [Fig. VIII-2-7] [Fig. VIII-2-8] The State of Connection If the connection is completed, user can see and copy the entire data of PDA with the folder, [Mobile Device] like [Fig. VIII-2-9] at Window Explorer. [Fig. VIII-2-9] PDA Folders at Window Explorer...

  • Page 64: The Theory For Calculating Rms By Iso2631 And Iso8041

    [Appendix 1] The Theory for calculating RMS by ISO2631 and ISO8041...
  • Page 65 ISO8041:1990 Annex D D. 1 Nomenclature : Instantaneous magnitude of signal μ or 1 : Reference magnitude of signal( ) if power is measured τ : Time constant for running averaging : Time : Time of observation : Start time of integration : Stop time of integration or exp : Exponential Function...
  • Page 66 The equivalent continuous vibration value or level can also be derived from the running level by true integration or by summing over discrete samples, being constant or nearly constant for a time interval as follows: ⎡ ⎤ ∑ ⎢ ⎥ eq T ⎣...

  • Page 67: Frequency Response Of Filter In The Vibration Level Meter

    [Appendix 2] Frequency Response of Filter in the Vibration Level Meter...

  • Page 68: Hz Highpass Filter

    1. 1Hz Highpass Filter A 2-pole Butterworth IIR Filter was used for this filter and integrator has highpass filter with 10Hz Cutoff frequency.

  • Page 69: Hz Highpass Filter

    2. 5Hz Highpass Filter A 2-pole Butterworth IIR Filter was used for this filter and integrator has highpass filter with 10Hz Cutoff frequency.

  • Page 70: Hz Highpass Filter

    3. 10Hz Highpass Filter A 2-pole Butterworth IIR Filter was used for this filter and integrator has highpass filter with 10Hz Cutoff frequency.

  • Page 71: Hz~300Hz Bandpass Filter

    4. 2Hz~300Hz Bandpass Filter A 4-pole Butterworth IIR Filter was used for this filter and integrator has highpass filter with 10Hz Cutoff frequency.

  • Page 72: Hz~1Khz Bandpass Filter

    5. 2Hz~1kHz Bandpass Filter A 4-pole Butterworth IIR Filter was used for this filter and integrator has highpass filter with 10Hz Cutoff frequency.

  • Page 73: Hz~500Hz Bandpass Filter

    6. 10Hz~500Hz Bandpass Filter A 4-pole Butterworth IIR Filter was used for this filter and integrator has highpass filter with 10Hz Cutoff frequency.

  • Page 74: Hz~1Khz Bandpass Filter

    7. 10Hz~1kHz Bandpass Filter A 4-pole Butterworth IIR Filter was used for this filter and integrator has highpass filter with 10Hz Cutoff frequency.

  • Page 75: Theory Of Wbcombined Filter And Frequency Response

    [Appendix 3] Theory of WBCombined Filter and Frequency Response (ISO6954 Filter)

  • Page 76: Theory

    1. Theory <Table 1. Parameters of the transfer functions of frequency weightings > Acceleration-velocity Band-limiting Upward step transition Weighting 12.5 12.5 0.63 2.37 0.91 3.35 0.91 ∞ ∞ 0.63 ∞ 0.08 0.63 0.25 0.86 0.0625 0.80 0.80 ∞ ∞ WBCombined 0.7943 5.684 ∞...
  • Page 77 ω ω ω For W.B.Combined this expression is replaced by ω ω ω c) Upward step(steepness approximately 6dB per octave, proportionality to jerk) ω ω ⎛ ω ⎞ ω ω ⋅ ⎜ ⎟ ω ω ⎝ ⎠ ω ω ω Where ω...
  • Page 78 t Δ leads directly to the differential operator , which may be approximated by in a digital t Δ realization of the weighting if the sampling interval is small enough. NOTE 2. Frequency weighting is considered to be the appropriate weighting curve for direction comfort in rail vehicles.
  • Page 79 <Fig. 2 Lowpass Filter with 100Hz Cutoff> <Fig. 3 a-v transition Frequency Response>...
  • Page 80 <Fig. 4 Frequency Response of Whole-body Combined Filter using s-function> <Fig. 5 Frequency Response of Whole-body Combined Filter using z-function>...
  • Page 81 <Fig. 6 Comparison of Whole-body Combined Filter> <Fig. 7 Impulse Response Function in the Matlab and C-code> A simulated impulse response function is same to a theoretical impulse response function in C- code’s algorithms as shown in [Fig. 7]. Where the sampling frequency for simulation is 2048Sample/sec, a buffer size is 4096.
  • Page 82 <Table 2. Error between Standard and Calculated Filter> Frequency WBCombined(dB) Error(%) Nominal TRUE Calculated Standard 0.100 -36.002 0.005555 0.125 0.12589 -32.004 0.012498 0.160 0.15849 -28.01 -28.01 0.200 0.19953 -24.022 -24.02 0.008326 0.250 0.25119 -20.051 -20.05 0.004987 0.315 0.31623 -16.121 -16.12 0.006203 0.400 0.39811...

  • Page 83: Frequency Response And Weight Factor Of Weighting Filter As Acceleration Input

    2. Frequency Response and weight factor of Weighting Filter as acceleration input <Fig. 8 Comparison of a theoretical acceleration and a measured acceleration (y-axis : Decibel)> <Fig. 9 Comparison of a theoretical acceleration and a measured acceleration (y-axis : Linear)>...
  • Page 84 <Fig. 10 Error Range and Acceleration’s Error > Error curve is in a upper and lower threshold line within band limiting frequencies. <Table 3. Combined frequency weighting, defined from 1Hz to 80Hz, in one-third-octave bands> Frequency WBCombined Weight Tolerance TRUE Nominal Factor W 0.1000...
  • Page 85 7.9430 8.000 0.582000 -4.70 10.0000 10.000 0.494000 -6.13 ± 1 12.5900 12.500 0.411000 -7.72 ± 1 15.8500 16.000 0.337000 -9.45 ± 1 19.9500 20.000 0.274000 -11.24 ± 1 25.1200 25.000 0.220000 -13.15 ± 1 31.6200 31.500 0.176000 -15.09 ± 1 39.8100 40.000 0.140000...

  • Page 86: Frequency Response And Weight Factor Of Weighting Filter As Velocity Input

    3. Frequency Response and weight factor of Weighting Filter as velocity input <Fig. 11> Velocity Weighting Factor <Table 4> Velocity Weight Factor in Human Vibration Velocity Weighting True Referen Calculat Frequency(Hz) Error(%) 0.0022 0.1995 0.00223 -0.679 0.0043 0.2512 0.00438 0.150 0.0087 0.3162 0.00868...
  • Page 87 1.585 0.260 0.261 -0.196 1.995 0.327 0.327 -0.028 2.512 0.402 0.402 -0.055 3.162 0.485 0.485 -0.035 3.981 0.573 0.573 -0.037 5.012 0.661 0.661 -0.024 6.310 0.743 0.743 0.013 7.943 0.813 0.813 -0.021 10.000 0.869 0.869 -0.036 12.590 0.911 0.911 -0.033 15.850 0.941 0.941...
  • Page 88 <Fig. 12> Error between theoretical value and measured value...

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