Can We USE ADXL345 Measuring Vibration Frequency or not?

One Customer use our ADXL345 to test their vibration acceleration and then figure out the displacement. Now they are asking us weather we can use this part(ADXL345) to measure the frequency of vibration or not. As ADXL345 is a triaxial(3X) accelerometer, if triaxial accelerometer cannot measure the vibration frequency, can they use an monaxial(1X) accelerometer to measure the vibration frequency? IF the answer is yes, can ADI provide the arithmetic or solution. Thanks a lot!

Ps: the product is similar with a Feeding controller, when the material was transportingthe controller will vibrate till the end. They use our ADXL345 to measure the accelerated speed.

  • Thank you for your post and for your support! I am out of the office, on vacation, until 1/9/2017, so I won't be able to offer much more support until this.  I have re-listed your questions, as I understand them and have offered preliminary responses. Did I interpret them correctly?  

    Question: Is it possible to measure the frequency of a sampled data signal?

    Answer: Yes, it is possible, to measure the frequency of a sampled signal, as long as you know that the majority of the spectral energy is within one Nyquist band (1/2 of the sample rate).

    Question: Can we offer routines?

    Answer: Maybe, it might be as simple as using a threshold (with hysteresis) to count the peaks, but the complexity of the motion in the application might require some filtering or spectral signal processing techniques, such as a FFT.   

    1. Are they sure that there is one dominant frequency in the vibration?  If so, how did they determine this? Can they share the data and their analysis method?

    2. What frequency range do they anticipate?

    3. What accuracy do they need, in order to be successful in this process? 

    Question: As ADXL345 is a triaxial(3X) accelerometer, if triaxial accelerometer cannot measure the vibration frequency, can they use an monaxial(1X) accelerometer to measure the vibration frequency?

    Answer: I am not sure that I understand this correctly?  What would having three axes be a disadvantage?  If the vibration is observable in one direction, they can ignore the other two axes in the ADXL345, right? .

    The bottom line is that this seems possible, but we to better understand what "success" means in this scenario, before we can understand what we might be able to do, in order to help.

  • Were you able to get any further definition on this?

  • Dear Mark,

    Thanks for your help and you have clarified for me in another e-mail     A Question of ADXL363 on Measuring Vibration Frequency

    This customer will use ADXL363 instead of ADXL345.

     

    Best Regards

     

    Zhenyu Zhao

    Excelpoint International Trading (Shanghai) Co., Ltd - Nanjing Office | Empowering Future Technology

    T +86 25 8689-3130 x 211  • M +86 177 6811 8284

    F +86 25 8689-3129 • QQ 1136 0958 91 •   <http://www.excelpoint.com.cn/> www.excelpoint.com.cn

     

    发件人: NevadaMark 

    发送时间: 2017年1月9日 20:31

    收件人: 振宇 赵 <zhao.zhenyu@excelpoint.com.cn>

    主题: Re:  - Re: Can We USE ADXL345 Measuring Vibration Frequency or not?

     

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    Re: Can We USE ADXL345 Measuring Vibration Frequency or not?

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