I have measured the vibration frequency response function a structure (blue curves in the following diagrams).
By using command
SYSD=tfest(SYSFR,5);
% SYSFR is the measured result (imported beginning from 25 Hz, as the
% low-frequency area is not accurate). SYSD is the approximated FRF.
I can approximate the measured FRF to a transfer function with 5 poles (the least amount of poles needed for the approximation to be accurate enough).

Since the measured FRF curves clearly have the shape of 2DOF vibration system, I want to further approximate the transfer function as the sum of two 1DOF vibration transfer functions, and draw both 1DOF vibration FRF curves in diagram (like in the following diagram). How to achieve this? The approximation can either be done based on measured FRF or approximated 5-pole FRF.I have measured the vibration frequency response function a structure (blue curves in the following diagrams).
By using command
SYSD=tfest(SYSFR,5);
% SYSFR is the measured result (imported beginning from 25 Hz, as the
% low-frequency area is not accurate). SYSD is the approximated FRF.
I can approximate the measured FRF to a transfer function with 5 poles (the least amount of poles needed for the approximation to be accurate enough).

Since the measured FRF curves clearly have the shape of 2DOF vibration system, I want to further approximate the transfer function as the sum of two 1DOF vibration transfer functions, and draw both 1DOF vibration FRF curves in diagram (like in the following diagram). How to achieve this? The approximation can either be done based on measured FRF or approximated 5-pole FRF. I have measured the vibration frequency response function a structure (blue curves in the following diagrams).
By using command
SYSD=tfest(SYSFR,5);
% SYSFR is the measured result (imported beginning from 25 Hz, as the
% low-frequency area is not accurate). SYSD is the approximated FRF.
I can approximate the measured FRF to a transfer function with 5 poles (the least amount of poles needed for the approximation to be accurate enough).

Since the measured FRF curves clearly have the shape of 2DOF vibration system, I want to further approximate the transfer function as the sum of two 1DOF vibration transfer functions, and draw both 1DOF vibration FRF curves in diagram (like in the following diagram). How to achieve this? The approximation can either be done based on measured FRF or approximated 5-pole FRF. frequency, transfer function MATLAB Answers — New Questions

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