This command will import analog signals in from an ASCII file written out by AMTI force plates, acting on all of the ACTIVE_FILES in the Visual3D Workspace.

Import_Analog_Signals_From_Amti_Ascii_File
! /REPLACE_EXISTING_SIGNALS=TRUE
/FREQUENCY= the analog frequency
! /FOLDER=
;

AMTI's ASCII file format contains 6 signals which, for example, would appear as:

-0.7106 , 0.0000 , 0.0000 , 0.0000 ,-22.4939 , 11.1253

-0.7106 , 0.0000 , 0.0000 , 0.0000 , 0.0000 , 11.1253

-0.7106 , 0.0000 , 0.0000 , 0.0000 , 0.0000 , 11.1253

-0.7106 , 0.0000 , 0.0000 , 0.0000 , 0.0000 , 11.1253

……

Visual3D assigns default signal names to these 6 signals:

A001 , A002 , A003 , A004 , A005 , A006

If these names exist in the C3D file already, then Visual3D checks the command's parameter /Replace_Existing_Signals to see if the signal should be replaced. If the signal should not be replaced, the name is incremented again.

In order to automate the processing of many files, Visual3D assumes that the ascii file as the same name as the c3d file, but .c3d is replaced with _a.txt

For example:

c3d file = c:/test.c3d
ascii file = c:/test_a.txt

The command assumes that the user is specifying the analog (sampling) frequency because this information is not contained in the data file. The analog frequency must be an integer multiple of the Motion Capture sampling rate. This command does not resample the data.

If there are more samples of ANALOG data than would fill corresponding frames of motion capture data, then Visual3D will just add the additional frames.

If there are two few frames, the signal is buffered with zeros at the end.

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