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vibration integration

I am integrating a vibration signal from acceleration to velocity. Using the integration function integral X(T)vi. I am sampling at 1,000 samples/second (500hz) and collecting 10,000 samples. I would like to know what initial and final boundry conditions I should use. I am placing the integration VI after a high pass filter set at 4 HZ. Should I place the integration function before the high pass filter? Any help will be greatly appreciated. Thanks
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Integration has a low pass frequency response. If you put the high pass filter first it will eliminate any DC component. A DC component will eventually cause the integrator to saturate unless it gets reset. Since you are filtering the DC out, I presume you are not interested in determining position. Thus, I would recommend high pass filtering first, then integrating.

As for initial conditions, it may depend upon what you are doing with the data, how many samples you are integrating at a time, etc. If the samples are taken continuously and integrated in blocks you might want to use shift registers to set the initial condition for block n to the final value from block n-1. Check the Help files for the Integrate VI for suggestions on appropriate use of the boundary conditions.

Lynn
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@johnsold wrote:
Integration has a low pass frequency response. If you put the high pass filter first it will eliminate any DC component. A DC component will eventually cause the integrator to saturate unless it gets reset. Since you are filtering the DC out, I presume you are not interested in determining position. Thus, I would recommend high pass filtering first, then integrating.

As for initial conditions, it may depend upon what you are doing with the data, how many samples you are integrating at a time, etc. If the samples are taken continuously and integrated in blocks you might want to use shift registers to set the initial condition for block n to the final value from block n-1. Check the Help files for the Integrate VI for suggestions on appropriate use of the boundary conditions.

Lynn


Thanks for the info
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