3. Description of the macro command and prerequisites

The operator CALC_TRANSFERT makes it possible to calculate the dynamic transfer function matrix between two points of the structure (input => output). It also allows the user to determine the signal at one point of the structure (at the input) knowing the signal at another point in the structure (at the output).

Figure 1 — Schematic representation of how to use the macro command

Prior to using the control, the user must perform several linear dynamic calculations under unidirectional stress. For example, if the study is in 3D (resp. 2D), he must perform 3 calculations (resp. 2 calculations) exciting one of the three (resp. 2) directions. It is preferable to carry out these dynamic calculations using mono-directional white noise.

Dynamic calculations must be performed with the same list of frequencies if the calculation is harmonic and with the same list of times if the calculation is transitory. For a transitory calculation, the user must take care to have a list of times at constant steps. Otherwise an error message will be sent to it because the Fourier transform necessary for the various calculations requires a constant step.

The dynamic calculations must be of the same type, either tran_gene, or harm_gene, or dyna_trans or dyna_harmo.

When the user has to fill in the training functions and/or the measured signals, it is preferable for them to be discretized on the same frequency list (case of a harmonic calculation) or on the same time list (case of a transient calculation).